diff options
Diffstat (limited to 'kernel')
61 files changed, 1991 insertions, 1281 deletions
diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c index 5bb5e49ef4c3..81e2f6995adb 100644 --- a/kernel/bpf/inode.c +++ b/kernel/bpf/inode.c @@ -150,39 +150,29 @@ static int bpf_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) return 0; } -static int bpf_mkobj_ops(struct inode *dir, struct dentry *dentry, - umode_t mode, const struct inode_operations *iops) +static int bpf_mkobj_ops(struct dentry *dentry, umode_t mode, void *raw, + const struct inode_operations *iops) { - struct inode *inode; - - inode = bpf_get_inode(dir->i_sb, dir, mode | S_IFREG); + struct inode *dir = dentry->d_parent->d_inode; + struct inode *inode = bpf_get_inode(dir->i_sb, dir, mode); if (IS_ERR(inode)) return PTR_ERR(inode); inode->i_op = iops; - inode->i_private = dentry->d_fsdata; + inode->i_private = raw; bpf_dentry_finalize(dentry, inode, dir); return 0; } -static int bpf_mkobj(struct inode *dir, struct dentry *dentry, umode_t mode, - dev_t devt) +static int bpf_mkprog(struct dentry *dentry, umode_t mode, void *arg) { - enum bpf_type type = MINOR(devt); - - if (MAJOR(devt) != UNNAMED_MAJOR || !S_ISREG(mode) || - dentry->d_fsdata == NULL) - return -EPERM; + return bpf_mkobj_ops(dentry, mode, arg, &bpf_prog_iops); +} - switch (type) { - case BPF_TYPE_PROG: - return bpf_mkobj_ops(dir, dentry, mode, &bpf_prog_iops); - case BPF_TYPE_MAP: - return bpf_mkobj_ops(dir, dentry, mode, &bpf_map_iops); - default: - return -EPERM; - } +static int bpf_mkmap(struct dentry *dentry, umode_t mode, void *arg) +{ + return bpf_mkobj_ops(dentry, mode, arg, &bpf_map_iops); } static struct dentry * @@ -218,7 +208,6 @@ static int bpf_symlink(struct inode *dir, struct dentry *dentry, static const struct inode_operations bpf_dir_iops = { .lookup = bpf_lookup, - .mknod = bpf_mkobj, .mkdir = bpf_mkdir, .symlink = bpf_symlink, .rmdir = simple_rmdir, @@ -234,7 +223,6 @@ static int bpf_obj_do_pin(const struct filename *pathname, void *raw, struct inode *dir; struct path path; umode_t mode; - dev_t devt; int ret; dentry = kern_path_create(AT_FDCWD, pathname->name, &path, 0); @@ -242,9 +230,8 @@ static int bpf_obj_do_pin(const struct filename *pathname, void *raw, return PTR_ERR(dentry); mode = S_IFREG | ((S_IRUSR | S_IWUSR) & ~current_umask()); - devt = MKDEV(UNNAMED_MAJOR, type); - ret = security_path_mknod(&path, dentry, mode, devt); + ret = security_path_mknod(&path, dentry, mode, 0); if (ret) goto out; @@ -254,9 +241,16 @@ static int bpf_obj_do_pin(const struct filename *pathname, void *raw, goto out; } - dentry->d_fsdata = raw; - ret = vfs_mknod(dir, dentry, mode, devt); - dentry->d_fsdata = NULL; + switch (type) { + case BPF_TYPE_PROG: + ret = vfs_mkobj(dentry, mode, bpf_mkprog, raw); + break; + case BPF_TYPE_MAP: + ret = vfs_mkobj(dentry, mode, bpf_mkmap, raw); + break; + default: + ret = -EPERM; + } out: done_path_create(&path, dentry); return ret; diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 7e4c44538119..8cda3bc3ae22 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -1397,7 +1397,7 @@ static char *cgroup_file_name(struct cgroup *cgrp, const struct cftype *cft, cgroup_on_dfl(cgrp) ? ss->name : ss->legacy_name, cft->name); else - strlcpy(buf, cft->name, CGROUP_FILE_NAME_MAX); + strscpy(buf, cft->name, CGROUP_FILE_NAME_MAX); return buf; } @@ -1864,9 +1864,9 @@ void init_cgroup_root(struct cgroup_root *root, struct cgroup_sb_opts *opts) root->flags = opts->flags; if (opts->release_agent) - strlcpy(root->release_agent_path, opts->release_agent, PATH_MAX); + strscpy(root->release_agent_path, opts->release_agent, PATH_MAX); if (opts->name) - strlcpy(root->name, opts->name, MAX_CGROUP_ROOT_NAMELEN); + strscpy(root->name, opts->name, MAX_CGROUP_ROOT_NAMELEN); if (opts->cpuset_clone_children) set_bit(CGRP_CPUSET_CLONE_CHILDREN, &root->cgrp.flags); } diff --git a/kernel/configs/nopm.config b/kernel/configs/nopm.config new file mode 100644 index 000000000000..81ff07863576 --- /dev/null +++ b/kernel/configs/nopm.config @@ -0,0 +1,15 @@ +CONFIG_PM=n +CONFIG_SUSPEND=n +CONFIG_HIBERNATION=n + +# Triggers PM on OMAP +CONFIG_CPU_IDLE=n + +# Triggers enablement via hibernate callbacks +CONFIG_XEN=n + +# ARM/ARM64 architectures that select PM unconditionally +CONFIG_ARCH_OMAP2PLUS_TYPICAL=n +CONFIG_ARCH_RENESAS=n +CONFIG_ARCH_TEGRA=n +CONFIG_ARCH_VEXPRESS=n diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index c8146d53ca67..dbb0781a0533 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -2441,7 +2441,6 @@ static int kdb_kill(int argc, const char **argv) long sig, pid; char *endp; struct task_struct *p; - struct siginfo info; if (argc != 2) return KDB_ARGCOUNT; @@ -2449,7 +2448,7 @@ static int kdb_kill(int argc, const char **argv) sig = simple_strtol(argv[1], &endp, 0); if (*endp) return KDB_BADINT; - if (sig >= 0) { + if ((sig >= 0) || !valid_signal(-sig)) { kdb_printf("Invalid signal parameter.<-signal>\n"); return 0; } @@ -2470,12 +2469,7 @@ static int kdb_kill(int argc, const char **argv) return 0; } p = p->group_leader; - info.si_signo = sig; - info.si_errno = 0; - info.si_code = SI_USER; - info.si_pid = pid; /* same capabilities as process being signalled */ - info.si_uid = 0; /* kdb has root authority */ - kdb_send_sig_info(p, &info); + kdb_send_sig(p, sig); return 0; } diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h index fc224fbcf954..1e5a502ba4a7 100644 --- a/kernel/debug/kdb/kdb_private.h +++ b/kernel/debug/kdb/kdb_private.h @@ -208,7 +208,7 @@ extern unsigned long kdb_task_state(const struct task_struct *p, extern void kdb_ps_suppressed(void); extern void kdb_ps1(const struct task_struct *p); extern void kdb_print_nameval(const char *name, unsigned long val); -extern void kdb_send_sig_info(struct task_struct *p, struct siginfo *info); +extern void kdb_send_sig(struct task_struct *p, int sig); extern void kdb_meminfo_proc_show(void); extern char *kdb_getstr(char *, size_t, const char *); extern void kdb_gdb_state_pass(char *buf); diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index 1b2be63c8528..772a43fea825 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -179,21 +179,6 @@ put_callchain_entry(int rctx) } struct perf_callchain_entry * -perf_callchain(struct perf_event *event, struct pt_regs *regs) -{ - bool kernel = !event->attr.exclude_callchain_kernel; - bool user = !event->attr.exclude_callchain_user; - /* Disallow cross-task user callchains. */ - bool crosstask = event->ctx->task && event->ctx->task != current; - const u32 max_stack = event->attr.sample_max_stack; - - if (!kernel && !user) - return NULL; - - return get_perf_callchain(regs, 0, kernel, user, max_stack, crosstask, true); -} - -struct perf_callchain_entry * get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user, u32 max_stack, bool crosstask, bool add_mark) { diff --git a/kernel/events/core.c b/kernel/events/core.c index 878d86c513d6..f0549e79978b 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -1231,6 +1231,10 @@ static void put_ctx(struct perf_event_context *ctx) * perf_event_context::lock * perf_event::mmap_mutex * mmap_sem + * + * cpu_hotplug_lock + * pmus_lock + * cpuctx->mutex / perf_event_context::mutex */ static struct perf_event_context * perf_event_ctx_lock_nested(struct perf_event *event, int nesting) @@ -4196,6 +4200,7 @@ int perf_event_release_kernel(struct perf_event *event) { struct perf_event_context *ctx = event->ctx; struct perf_event *child, *tmp; + LIST_HEAD(free_list); /* * If we got here through err_file: fput(event_file); we will not have @@ -4268,8 +4273,7 @@ again: struct perf_event, child_list); if (tmp == child) { perf_remove_from_context(child, DETACH_GROUP); - list_del(&child->child_list); - free_event(child); + list_move(&child->child_list, &free_list); /* * This matches the refcount bump in inherit_event(); * this can't be the last reference. @@ -4284,6 +4288,11 @@ again: } mutex_unlock(&event->child_mutex); + list_for_each_entry_safe(child, tmp, &free_list, child_list) { + list_del(&child->child_list); + free_event(child); + } + no_ctx: put_event(event); /* Must be the 'last' reference */ return 0; @@ -4511,11 +4520,11 @@ perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) return ret; } -static unsigned int perf_poll(struct file *file, poll_table *wait) +static __poll_t perf_poll(struct file *file, poll_table *wait) { struct perf_event *event = file->private_data; struct ring_buffer *rb; - unsigned int events = POLLHUP; + __poll_t events = POLLHUP; poll_wait(file, &event->waitq, wait); @@ -4907,6 +4916,7 @@ void perf_event_update_userpage(struct perf_event *event) unlock: rcu_read_unlock(); } +EXPORT_SYMBOL_GPL(perf_event_update_userpage); static int perf_mmap_fault(struct vm_fault *vmf) { @@ -5818,19 +5828,11 @@ void perf_output_sample(struct perf_output_handle *handle, perf_output_read(handle, event); if (sample_type & PERF_SAMPLE_CALLCHAIN) { - if (data->callchain) { - int size = 1; - - if (data->callchain) - size += data->callchain->nr; - - size *= sizeof(u64); + int size = 1; - __output_copy(handle, data->callchain, size); - } else { - u64 nr = 0; - perf_output_put(handle, nr); - } + size += data->callchain->nr; + size *= sizeof(u64); + __output_copy(handle, data->callchain, size); } if (sample_type & PERF_SAMPLE_RAW) { @@ -5983,6 +5985,26 @@ static u64 perf_virt_to_phys(u64 virt) return phys_addr; } +static struct perf_callchain_entry __empty_callchain = { .nr = 0, }; + +static struct perf_callchain_entry * +perf_callchain(struct perf_event *event, struct pt_regs *regs) +{ + bool kernel = !event->attr.exclude_callchain_kernel; + bool user = !event->attr.exclude_callchain_user; + /* Disallow cross-task user callchains. */ + bool crosstask = event->ctx->task && event->ctx->task != current; + const u32 max_stack = event->attr.sample_max_stack; + struct perf_callchain_entry *callchain; + + if (!kernel && !user) + return &__empty_callchain; + + callchain = get_perf_callchain(regs, 0, kernel, user, + max_stack, crosstask, true); + return callchain ?: &__empty_callchain; +} + void perf_prepare_sample(struct perf_event_header *header, struct perf_sample_data *data, struct perf_event *event, @@ -6005,9 +6027,7 @@ void perf_prepare_sample(struct perf_event_header *header, int size = 1; data->callchain = perf_callchain(event, regs); - - if (data->callchain) - size += data->callchain->nr; + size += data->callchain->nr; header->size += size * sizeof(u64); } @@ -8526,6 +8546,29 @@ fail_clear_files: return ret; } +static int +perf_tracepoint_set_filter(struct perf_event *event, char *filter_str) +{ + struct perf_event_context *ctx = event->ctx; + int ret; + + /* + * Beware, here be dragons!! + * + * the tracepoint muck will deadlock against ctx->mutex, but the tracepoint + * stuff does not actually need it. So temporarily drop ctx->mutex. As per + * perf_event_ctx_lock() we already have a reference on ctx. + * + * This can result in event getting moved to a different ctx, but that + * does not affect the tracepoint state. + */ + mutex_unlock(&ctx->mutex); + ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); + mutex_lock(&ctx->mutex); + + return ret; +} + static int perf_event_set_filter(struct perf_event *event, void __user *arg) { char *filter_str; @@ -8542,8 +8585,7 @@ static int perf_event_set_filter(struct perf_event *event, void __user *arg) if (IS_ENABLED(CONFIG_EVENT_TRACING) && event->attr.type == PERF_TYPE_TRACEPOINT) - ret = ftrace_profile_set_filter(event, event->attr.config, - filter_str); + ret = perf_tracepoint_set_filter(event, filter_str); else if (has_addr_filter(event)) ret = perf_event_set_addr_filter(event, filter_str); @@ -9178,7 +9220,13 @@ static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) if (!try_module_get(pmu->module)) return -ENODEV; - if (event->group_leader != event) { + /* + * A number of pmu->event_init() methods iterate the sibling_list to, + * for example, validate if the group fits on the PMU. Therefore, + * if this is a sibling event, acquire the ctx->mutex to protect + * the sibling_list. + */ + if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { /* * This ctx->mutex can nest when we're called through * inheritance. See the perf_event_ctx_lock_nested() comment. @@ -10713,6 +10761,19 @@ inherit_event(struct perf_event *parent_event, if (IS_ERR(child_event)) return child_event; + + if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && + !child_ctx->task_ctx_data) { + struct pmu *pmu = child_event->pmu; + + child_ctx->task_ctx_data = kzalloc(pmu->task_ctx_size, + GFP_KERNEL); + if (!child_ctx->task_ctx_data) { + free_event(child_event); + return NULL; + } + } + /* * is_orphaned_event() and list_add_tail(&parent_event->child_list) * must be under the same lock in order to serialize against @@ -10723,6 +10784,7 @@ inherit_event(struct perf_event *parent_event, if (is_orphaned_event(parent_event) || !atomic_long_inc_not_zero(&parent_event->refcount)) { mutex_unlock(&parent_event->child_mutex); + /* task_ctx_data is freed with child_ctx */ free_event(child_event); return NULL; } diff --git a/kernel/events/internal.h b/kernel/events/internal.h index 09b1537ae06c..6dc725a7e7bc 100644 --- a/kernel/events/internal.h +++ b/kernel/events/internal.h @@ -201,10 +201,6 @@ arch_perf_out_copy_user(void *dst, const void *src, unsigned long n) DEFINE_OUTPUT_COPY(__output_copy_user, arch_perf_out_copy_user) -/* Callchain handling */ -extern struct perf_callchain_entry * -perf_callchain(struct perf_event *event, struct pt_regs *regs); - static inline int get_recursion_context(int *recursion) { int rctx; diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 267f6ef91d97..ce6848e46e94 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1167,8 +1167,8 @@ static int xol_add_vma(struct mm_struct *mm, struct xol_area *area) } ret = 0; - smp_wmb(); /* pairs with get_xol_area() */ - mm->uprobes_state.xol_area = area; + /* pairs with get_xol_area() */ + smp_store_release(&mm->uprobes_state.xol_area, area); /* ^^^ */ fail: up_write(&mm->mmap_sem); @@ -1230,8 +1230,8 @@ static struct xol_area *get_xol_area(void) if (!mm->uprobes_state.xol_area) __create_xol_area(0); - area = mm->uprobes_state.xol_area; - smp_read_barrier_depends(); /* pairs with wmb in xol_add_vma() */ + /* Pairs with xol_add_vma() smp_store_release() */ + area = READ_ONCE(mm->uprobes_state.xol_area); /* ^^^ */ return area; } @@ -1528,8 +1528,8 @@ static unsigned long get_trampoline_vaddr(void) struct xol_area *area; unsigned long trampoline_vaddr = -1; - area = current->mm->uprobes_state.xol_area; - smp_read_barrier_depends(); + /* Pairs with xol_add_vma() smp_store_release() */ + area = READ_ONCE(current->mm->uprobes_state.xol_area); /* ^^^ */ if (area) trampoline_vaddr = area->vaddr; diff --git a/kernel/futex.c b/kernel/futex.c index 8c5424dd5924..7f719d110908 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2311,9 +2311,6 @@ static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q, raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock); oldowner = pi_state->owner; - /* Owner died? */ - if (!pi_state->owner) - newtid |= FUTEX_OWNER_DIED; /* * We are here because either: @@ -2374,6 +2371,9 @@ retry: } newtid = task_pid_vnr(newowner) | FUTEX_WAITERS; + /* Owner died? */ + if (!pi_state->owner) + newtid |= FUTEX_OWNER_DIED; if (get_futex_value_locked(&uval, uaddr)) goto handle_fault; diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig index 89e355866450..6fc87ccda1d7 100644 --- a/kernel/irq/Kconfig +++ b/kernel/irq/Kconfig @@ -103,16 +103,6 @@ config GENERIC_IRQ_MATRIX_ALLOCATOR config GENERIC_IRQ_RESERVATION_MODE bool -config IRQ_DOMAIN_DEBUG - bool "Expose hardware/virtual IRQ mapping via debugfs" - depends on IRQ_DOMAIN && DEBUG_FS - help - This option will show the mapping relationship between hardware irq - numbers and Linux irq numbers. The mapping is exposed via debugfs - in the file "irq_domain_mapping". - - If you don't know what this means you don't need it. - # Support forced irq threading config IRQ_FORCED_THREADING bool diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c index e12d35108225..a37a3b4b6342 100644 --- a/kernel/irq/affinity.c +++ b/kernel/irq/affinity.c @@ -39,7 +39,7 @@ static void irq_spread_init_one(struct cpumask *irqmsk, struct cpumask *nmsk, } } -static cpumask_var_t *alloc_node_to_present_cpumask(void) +static cpumask_var_t *alloc_node_to_possible_cpumask(void) { cpumask_var_t *masks; int node; @@ -62,7 +62,7 @@ out_unwind: return NULL; } -static void free_node_to_present_cpumask(cpumask_var_t *masks) +static void free_node_to_possible_cpumask(cpumask_var_t *masks) { int node; @@ -71,22 +71,22 @@ static void free_node_to_present_cpumask(cpumask_var_t *masks) kfree(masks); } -static void build_node_to_present_cpumask(cpumask_var_t *masks) +static void build_node_to_possible_cpumask(cpumask_var_t *masks) { int cpu; - for_each_present_cpu(cpu) + for_each_possible_cpu(cpu) cpumask_set_cpu(cpu, masks[cpu_to_node(cpu)]); } -static int get_nodes_in_cpumask(cpumask_var_t *node_to_present_cpumask, +static int get_nodes_in_cpumask(cpumask_var_t *node_to_possible_cpumask, const struct cpumask *mask, nodemask_t *nodemsk) { int n, nodes = 0; /* Calculate the number of nodes in the supplied affinity mask */ for_each_node(n) { - if (cpumask_intersects(mask, node_to_present_cpumask[n])) { + if (cpumask_intersects(mask, node_to_possible_cpumask[n])) { node_set(n, *nodemsk); nodes++; } @@ -109,7 +109,7 @@ irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd) int last_affv = affv + affd->pre_vectors; nodemask_t nodemsk = NODE_MASK_NONE; struct cpumask *masks; - cpumask_var_t nmsk, *node_to_present_cpumask; + cpumask_var_t nmsk, *node_to_possible_cpumask; /* * If there aren't any vectors left after applying the pre/post @@ -125,8 +125,8 @@ irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd) if (!masks) goto out; - node_to_present_cpumask = alloc_node_to_present_cpumask(); - if (!node_to_present_cpumask) + node_to_possible_cpumask = alloc_node_to_possible_cpumask(); + if (!node_to_possible_cpumask) goto out; /* Fill out vectors at the beginning that don't need affinity */ @@ -135,8 +135,8 @@ irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd) /* Stabilize the cpumasks */ get_online_cpus(); - build_node_to_present_cpumask(node_to_present_cpumask); - nodes = get_nodes_in_cpumask(node_to_present_cpumask, cpu_present_mask, + build_node_to_possible_cpumask(node_to_possible_cpumask); + nodes = get_nodes_in_cpumask(node_to_possible_cpumask, cpu_possible_mask, &nodemsk); /* @@ -146,7 +146,7 @@ irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd) if (affv <= nodes) { for_each_node_mask(n, nodemsk) { cpumask_copy(masks + curvec, - node_to_present_cpumask[n]); + node_to_possible_cpumask[n]); if (++curvec == last_affv) break; } @@ -160,7 +160,7 @@ irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd) vecs_per_node = (affv - (curvec - affd->pre_vectors)) / nodes; /* Get the cpus on this node which are in the mask */ - cpumask_and(nmsk, cpu_present_mask, node_to_present_cpumask[n]); + cpumask_and(nmsk, cpu_possible_mask, node_to_possible_cpumask[n]); /* Calculate the number of cpus per vector */ ncpus = cpumask_weight(nmsk); @@ -192,7 +192,7 @@ done: /* Fill out vectors at the end that don't need affinity */ for (; curvec < nvecs; curvec++) cpumask_copy(masks + curvec, irq_default_affinity); - free_node_to_present_cpumask(node_to_present_cpumask); + free_node_to_possible_cpumask(node_to_possible_cpumask); out: free_cpumask_var(nmsk); return masks; @@ -214,7 +214,7 @@ int irq_calc_affinity_vectors(int minvec, int maxvec, const struct irq_affinity return 0; get_online_cpus(); - ret = min_t(int, cpumask_weight(cpu_present_mask), vecs) + resv; + ret = min_t(int, cpumask_weight(cpu_possible_mask), vecs) + resv; put_online_cpus(); return ret; } diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 62068ad46930..e6a9c36470ee 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -897,124 +897,6 @@ unsigned int irq_find_mapping(struct irq_domain *domain, } EXPORT_SYMBOL_GPL(irq_find_mapping); -#ifdef CONFIG_IRQ_DOMAIN_DEBUG -static void virq_debug_show_one(struct seq_file *m, struct irq_desc *desc) -{ - struct irq_domain *domain; - struct irq_data *data; - - domain = desc->irq_data.domain; - data = &desc->irq_data; - - while (domain) { - unsigned int irq = data->irq; - unsigned long hwirq = data->hwirq; - struct irq_chip *chip; - bool direct; - - if (data == &desc->irq_data) - seq_printf(m, "%5d ", irq); - else - seq_printf(m, "%5d+ ", irq); - seq_printf(m, "0x%05lx ", hwirq); - - chip = irq_data_get_irq_chip(data); - seq_printf(m, "%-15s ", (chip && chip->name) ? chip->name : "none"); - - seq_printf(m, "0x%p ", irq_data_get_irq_chip_data(data)); - - seq_printf(m, " %c ", (desc->action && desc->action->handler) ? '*' : ' '); - direct = (irq == hwirq) && (irq < domain->revmap_direct_max_irq); - seq_printf(m, "%6s%-8s ", - (hwirq < domain->revmap_size) ? "LINEAR" : "RADIX", - direct ? "(DIRECT)" : ""); - seq_printf(m, "%s\n", domain->name); -#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY - domain = domain->parent; - data = data->parent_data; -#else - domain = NULL; -#endif - } -} - -static int virq_debug_show(struct seq_file *m, void *private) -{ - unsigned long flags; - struct irq_desc *desc; - struct irq_domain *domain; - struct radix_tree_iter iter; - void __rcu **slot; - int i; - - seq_printf(m, " %-16s %-6s %-10s %-10s %s\n", - "name", "mapped", "linear-max", "direct-max", "devtree-node"); - mutex_lock(&irq_domain_mutex); - list_for_each_entry(domain, &irq_domain_list, link) { - struct device_node *of_node; - const char *name; - - int count = 0; - - of_node = irq_domain_get_of_node(domain); - if (of_node) - name = of_node_full_name(of_node); - else if (is_fwnode_irqchip(domain->fwnode)) - name = container_of(domain->fwnode, struct irqchip_fwid, - fwnode)->name; - else - name = ""; - - radix_tree_for_each_slot(slot, &domain->revmap_tree, &iter, 0) - count++; - seq_printf(m, "%c%-16s %6u %10u %10u %s\n", - domain == irq_default_domain ? '*' : ' ', domain->name, - domain->revmap_size + count, domain->revmap_size, - domain->revmap_direct_max_irq, - name); - } - mutex_unlock(&irq_domain_mutex); - - seq_printf(m, "%-5s %-7s %-15s %-*s %6s %-14s %s\n", "irq", "hwirq", - "chip name", (int)(2 * sizeof(void *) + 2), "chip data", - "active", "type", "domain"); - - for (i = 1; i < nr_irqs; i++) { - desc = irq_to_desc(i); - if (!desc) - continue; - - raw_spin_lock_irqsave(&desc->lock, flags); - virq_debug_show_one(m, desc); - raw_spin_unlock_irqrestore(&desc->lock, flags); - } - - return 0; -} - -static int virq_debug_open(struct inode *inode, struct file *file) -{ - return single_open(file, virq_debug_show, inode->i_private); -} - -static const struct file_operations virq_debug_fops = { - .open = virq_debug_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; - -static int __init irq_debugfs_init(void) -{ - if (debugfs_create_file("irq_domain_mapping", S_IRUGO, NULL, - NULL, &virq_debug_fops) == NULL) - return -ENOMEM; - - return 0; -} -__initcall(irq_debugfs_init); -#endif /* CONFIG_IRQ_DOMAIN_DEBUG */ - /** * irq_domain_xlate_onecell() - Generic xlate for direct one cell bindings * diff --git a/kernel/irq_work.c b/kernel/irq_work.c index 40e9d739c169..6b7cdf17ccf8 100644 --- a/kernel/irq_work.c +++ b/kernel/irq_work.c @@ -36,7 +36,7 @@ static bool irq_work_claim(struct irq_work *work) */ flags = work->flags & ~IRQ_WORK_PENDING; for (;;) { - nflags = flags | IRQ_WORK_FLAGS; + nflags = flags | IRQ_WORK_CLAIMED; oflags = cmpxchg(&work->flags, flags, nflags); if (oflags == flags) break; diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 8594d24e4adc..b4517095db6a 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -79,7 +79,7 @@ int static_key_count(struct static_key *key) } EXPORT_SYMBOL_GPL(static_key_count); -static void static_key_slow_inc_cpuslocked(struct static_key *key) +void static_key_slow_inc_cpuslocked(struct static_key *key) { int v, v1; @@ -180,7 +180,7 @@ void static_key_disable(struct static_key *key) } EXPORT_SYMBOL_GPL(static_key_disable); -static void static_key_slow_dec_cpuslocked(struct static_key *key, +static void __static_key_slow_dec_cpuslocked(struct static_key *key, unsigned long rate_limit, struct delayed_work *work) { @@ -211,7 +211,7 @@ static void __static_key_slow_dec(struct static_key *key, struct delayed_work *work) { cpus_read_lock(); - static_key_slow_dec_cpuslocked(key, rate_limit, work); + __static_key_slow_dec_cpuslocked(key, rate_limit, work); cpus_read_unlock(); } @@ -229,6 +229,12 @@ void static_key_slow_dec(struct static_key *key) } EXPORT_SYMBOL_GPL(static_key_slow_dec); +void static_key_slow_dec_cpuslocked(struct static_key *key) +{ + STATIC_KEY_CHECK_USE(key); + __static_key_slow_dec_cpuslocked(key, 0, NULL); +} + void static_key_slow_dec_deferred(struct static_key_deferred *key) { STATIC_KEY_CHECK_USE(key); diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index de9e45dca70f..3a4656fb7047 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -366,11 +366,6 @@ static int __klp_enable_patch(struct klp_patch *patch) /* * A reference is taken on the patch module to prevent it from being * unloaded. - * - * Note: For immediate (no consistency model) patches we don't allow - * patch modules to unload since there is no safe/sane method to - * determine if a thread is still running in the patched code contained - * in the patch module once the ftrace registration is successful. */ if (!try_module_get(patch->mod)) return -ENODEV; @@ -454,6 +449,8 @@ EXPORT_SYMBOL_GPL(klp_enable_patch); * /sys/kernel/livepatch/<patch> * /sys/kernel/livepatch/<patch>/enabled * /sys/kernel/livepatch/<patch>/transition + * /sys/kernel/livepatch/<patch>/signal + * /sys/kernel/livepatch/<patch>/force * /sys/kernel/livepatch/<patch>/<object> * /sys/kernel/livepatch/<patch>/<object>/<function,sympos> */ @@ -528,11 +525,73 @@ static ssize_t transition_show(struct kobject *kobj, patch == klp_transition_patch); } +static ssize_t signal_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct klp_patch *patch; + int ret; + bool val; + + ret = kstrtobool(buf, &val); + if (ret) + return ret; + + if (!val) + return count; + + mutex_lock(&klp_mutex); + + patch = container_of(kobj, struct klp_patch, kobj); + if (patch != klp_transition_patch) { + mutex_unlock(&klp_mutex); + return -EINVAL; + } + + klp_send_signals(); + + mutex_unlock(&klp_mutex); + + return count; +} + +static ssize_t force_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct klp_patch *patch; + int ret; + bool val; + + ret = kstrtobool(buf, &val); + if (ret) + return ret; + + if (!val) + return count; + + mutex_lock(&klp_mutex); + + patch = container_of(kobj, struct klp_patch, kobj); + if (patch != klp_transition_patch) { + mutex_unlock(&klp_mutex); + return -EINVAL; + } + + klp_force_transition(); + + mutex_unlock(&klp_mutex); + + return count; +} + static struct kobj_attribute enabled_kobj_attr = __ATTR_RW(enabled); static struct kobj_attribute transition_kobj_attr = __ATTR_RO(transition); +static struct kobj_attribute signal_kobj_attr = __ATTR_WO(signal); +static struct kobj_attribute force_kobj_attr = __ATTR_WO(force); static struct attribute *klp_patch_attrs[] = { &enabled_kobj_attr.attr, &transition_kobj_attr.attr, + &signal_kobj_attr.attr, + &force_kobj_attr.attr, NULL }; @@ -830,12 +889,7 @@ int klp_register_patch(struct klp_patch *patch) if (!klp_initialized()) return -ENODEV; - /* - * Architectures without reliable stack traces have to set - * patch->immediate because there's currently no way to patch kthreads - * with the consistency model. - */ - if (!klp_have_reliable_stack() && !patch->immediate) { + if (!klp_have_reliable_stack()) { pr_err("This architecture doesn't have support for the livepatch consistency model.\n"); return -ENOSYS; } diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c index 56add6327736..7c6631e693bc 100644 --- a/kernel/livepatch/transition.c +++ b/kernel/livepatch/transition.c @@ -33,6 +33,8 @@ struct klp_patch *klp_transition_patch; static int klp_target_state = KLP_UNDEFINED; +static bool klp_forced = false; + /* * This work can be performed periodically to finish patching or unpatching any * "straggler" tasks which failed to transition in the first attempt. @@ -80,7 +82,6 @@ static void klp_complete_transition(void) struct klp_func *func; struct task_struct *g, *task; unsigned int cpu; - bool immediate_func = false; pr_debug("'%s': completing %s transition\n", klp_transition_patch->mod->name, @@ -102,16 +103,9 @@ static void klp_complete_transition(void) klp_synchronize_transition(); } - if (klp_transition_patch->immediate) - goto done; - - klp_for_each_object(klp_transition_patch, obj) { - klp_for_each_func(obj, func) { + klp_for_each_object(klp_transition_patch, obj) + klp_for_each_func(obj, func) func->transition = false; - if (func->immediate) - immediate_func = true; - } - } /* Prevent klp_ftrace_handler() from seeing KLP_UNDEFINED state */ if (klp_target_state == KLP_PATCHED) @@ -130,7 +124,6 @@ static void klp_complete_transition(void) task->patch_state = KLP_UNDEFINED; } -done: klp_for_each_object(klp_transition_patch, obj) { if (!klp_is_object_loaded(obj)) continue; @@ -144,13 +137,11 @@ done: klp_target_state == KLP_PATCHED ? "patching" : "unpatching"); /* - * See complementary comment in __klp_enable_patch() for why we - * keep the module reference for immediate patches. + * klp_forced set implies unbounded increase of module's ref count if + * the module is disabled/enabled in a loop. */ - if (!klp_transition_patch->immediate && !immediate_func && - klp_target_state == KLP_UNPATCHED) { + if (!klp_forced && klp_target_state == KLP_UNPATCHED) module_put(klp_transition_patch->mod); - } klp_target_state = KLP_UNDEFINED; klp_transition_patch = NULL; @@ -218,9 +209,6 @@ static int klp_check_stack_func(struct klp_func *func, struct klp_ops *ops; int i; - if (func->immediate) - return 0; - for (i = 0; i < trace->nr_entries; i++) { address = trace->entries[i]; @@ -383,13 +371,6 @@ void klp_try_complete_transition(void) WARN_ON_ONCE(klp_target_state == KLP_UNDEFINED); /* - * If the patch can be applied or reverted immediately, skip the - * per-task transitions. - */ - if (klp_transition_patch->immediate) - goto success; - - /* * Try to switch the tasks to the target patch state by walking their * stacks and looking for any to-be-patched or to-be-unpatched * functions. If such functions are found on a stack, or if the stack @@ -432,7 +413,6 @@ void klp_try_complete_transition(void) return; } -success: /* we're done, now cleanup the data structures */ klp_complete_transition(); } @@ -453,13 +433,6 @@ void klp_start_transition(void) klp_target_state == KLP_PATCHED ? "patching" : "unpatching"); /* - * If the patch can be applied or reverted immediately, skip the - * per-task transitions. - */ - if (klp_transition_patch->immediate) - return; - - /* * Mark all normal tasks as needing a patch state update. They'll * switch either in klp_try_complete_transition() or as they exit the * kernel. @@ -509,13 +482,6 @@ void klp_init_transition(struct klp_patch *patch, int state) klp_target_state == KLP_PATCHED ? "patching" : "unpatching"); /* - * If the patch can be applied or reverted immediately, skip the - * per-task transitions. - */ - if (patch->immediate) - return; - - /* * Initialize all tasks to the initial patch state to prepare them for * switching to the target state. */ @@ -608,3 +574,71 @@ void klp_copy_process(struct task_struct *child) /* TIF_PATCH_PENDING gets copied in setup_thread_stack() */ } + +/* + * Sends a fake signal to all non-kthread tasks with TIF_PATCH_PENDING set. + * Kthreads with TIF_PATCH_PENDING set are woken up. Only admin can request this + * action currently. + */ +void klp_send_signals(void) +{ + struct task_struct *g, *task; + + pr_notice("signaling remaining tasks\n"); + + read_lock(&tasklist_lock); + for_each_process_thread(g, task) { + if (!klp_patch_pending(task)) + continue; + + /* + * There is a small race here. We could see TIF_PATCH_PENDING + * set and decide to wake up a kthread or send a fake signal. + * Meanwhile the task could migrate itself and the action + * would be meaningless. It is not serious though. + */ + if (task->flags & PF_KTHREAD) { + /* + * Wake up a kthread which sleeps interruptedly and + * still has not been migrated. + */ + wake_up_state(task, TASK_INTERRUPTIBLE); + } else { + /* + * Send fake signal to all non-kthread tasks which are + * still not migrated. + */ + spin_lock_irq(&task->sighand->siglock); + signal_wake_up(task, 0); + spin_unlock_irq(&task->sighand->siglock); + } + } + read_unlock(&tasklist_lock); +} + +/* + * Drop TIF_PATCH_PENDING of all tasks on admin's request. This forces an + * existing transition to finish. + * + * NOTE: klp_update_patch_state(task) requires the task to be inactive or + * 'current'. This is not the case here and the consistency model could be + * broken. Administrator, who is the only one to execute the + * klp_force_transitions(), has to be aware of this. + */ +void klp_force_transition(void) +{ + struct task_struct *g, *task; + unsigned int cpu; + + pr_warn("forcing remaining tasks to the patched state\n"); + + read_lock(&tasklist_lock); + for_each_process_thread(g, task) + klp_update_patch_state(task); + read_unlock(&tasklist_lock); + + for_each_possible_cpu(cpu) + klp_update_patch_state(idle_task(cpu)); + + klp_forced = true; +} diff --git a/kernel/livepatch/transition.h b/kernel/livepatch/transition.h index 0f6e27c481f9..f9d0bc016067 100644 --- a/kernel/livepatch/transition.h +++ b/kernel/livepatch/transition.h @@ -11,5 +11,7 @@ void klp_cancel_transition(void); void klp_start_transition(void); void klp_try_complete_transition(void); void klp_reverse_transition(void); +void klp_send_signals(void); +void klp_force_transition(void); #endif /* _LIVEPATCH_TRANSITION_H */ diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 5fa1324a4f29..89b5f83f1969 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -49,6 +49,7 @@ #include <linux/gfp.h> #include <linux/random.h> #include <linux/jhash.h> +#include <linux/nmi.h> #include <asm/sections.h> @@ -647,18 +648,12 @@ static int count_matching_names(struct lock_class *new_class) return count + 1; } -/* - * Register a lock's class in the hash-table, if the class is not present - * yet. Otherwise we look it up. We cache the result in the lock object - * itself, so actual lookup of the hash should be once per lock object. - */ static inline struct lock_class * -look_up_lock_class(struct lockdep_map *lock, unsigned int subclass) +look_up_lock_class(const struct lockdep_map *lock, unsigned int subclass) { struct lockdep_subclass_key *key; struct hlist_head *hash_head; struct lock_class *class; - bool is_static = false; if (unlikely(subclass >= MAX_LOCKDEP_SUBCLASSES)) { debug_locks_off(); @@ -671,24 +666,11 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass) } /* - * Static locks do not have their class-keys yet - for them the key - * is the lock object itself. If the lock is in the per cpu area, - * the canonical address of the lock (per cpu offset removed) is - * used. + * If it is not initialised then it has never been locked, + * so it won't be present in the hash table. */ - if (unlikely(!lock->key)) { - unsigned long can_addr, addr = (unsigned long)lock; - - if (__is_kernel_percpu_address(addr, &can_addr)) - lock->key = (void *)can_addr; - else if (__is_module_percpu_address(addr, &can_addr)) - lock->key = (void *)can_addr; - else if (static_obj(lock)) - lock->key = (void *)lock; - else - return ERR_PTR(-EINVAL); - is_static = true; - } + if (unlikely(!lock->key)) + return NULL; /* * NOTE: the class-key must be unique. For dynamic locks, a static @@ -720,7 +702,35 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass) } } - return is_static || static_obj(lock->key) ? NULL : ERR_PTR(-EINVAL); + return NULL; +} + +/* + * Static locks do not have their class-keys yet - for them the key is + * the lock object itself. If the lock is in the per cpu area, the + * canonical address of the lock (per cpu offset removed) is used. + */ +static bool assign_lock_key(struct lockdep_map *lock) +{ + unsigned long can_addr, addr = (unsigned long)lock; + + if (__is_kernel_percpu_address(addr, &can_addr)) + lock->key = (void *)can_addr; + else if (__is_module_percpu_address(addr, &can_addr)) + lock->key = (void *)can_addr; + else if (static_obj(lock)) + lock->key = (void *)lock; + else { + /* Debug-check: all keys must be persistent! */ + debug_locks_off(); + pr_err("INFO: trying to register non-static key.\n"); + pr_err("the code is fine but needs lockdep annotation.\n"); + pr_err("turning off the locking correctness validator.\n"); + dump_stack(); + return false; + } + + return true; } /* @@ -738,18 +748,13 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force) DEBUG_LOCKS_WARN_ON(!irqs_disabled()); class = look_up_lock_class(lock, subclass); - if (likely(!IS_ERR_OR_NULL(class))) + if (likely(class)) goto out_set_class_cache; - /* - * Debug-check: all keys must be persistent! - */ - if (IS_ERR(class)) { - debug_locks_off(); - printk("INFO: trying to register non-static key.\n"); - printk("the code is fine but needs lockdep annotation.\n"); - printk("turning off the locking correctness validator.\n"); - dump_stack(); + if (!lock->key) { + if (!assign_lock_key(lock)) + return NULL; + } else if (!static_obj(lock->key)) { return NULL; } @@ -3272,7 +3277,7 @@ print_lock_nested_lock_not_held(struct task_struct *curr, return 0; } -static int __lock_is_held(struct lockdep_map *lock, int read); +static int __lock_is_held(const struct lockdep_map *lock, int read); /* * This gets called for every mutex_lock*()/spin_lock*() operation. @@ -3481,13 +3486,14 @@ print_unlock_imbalance_bug(struct task_struct *curr, struct lockdep_map *lock, return 0; } -static int match_held_lock(struct held_lock *hlock, struct lockdep_map *lock) +static int match_held_lock(const struct held_lock *hlock, + const struct lockdep_map *lock) { if (hlock->instance == lock) return 1; if (hlock->references) { - struct lock_class *class = lock->class_cache[0]; + const struct lock_class *class = lock->class_cache[0]; if (!class) class = look_up_lock_class(lock, 0); @@ -3498,7 +3504,7 @@ static int match_held_lock(struct held_lock *hlock, struct lockdep_map *lock) * Clearly if the lock hasn't been acquired _ever_, we're not * holding it either, so report failure. */ - if (IS_ERR_OR_NULL(class)) + if (!class) return 0; /* @@ -3723,7 +3729,7 @@ __lock_release(struct lockdep_map *lock, int nested, unsigned long ip) return 1; } -static int __lock_is_held(struct lockdep_map *lock, int read) +static int __lock_is_held(const struct lockdep_map *lock, int read) { struct task_struct *curr = current; int i; @@ -3937,7 +3943,7 @@ void lock_release(struct lockdep_map *lock, int nested, } EXPORT_SYMBOL_GPL(lock_release); -int lock_is_held_type(struct lockdep_map *lock, int read) +int lock_is_held_type(const struct lockdep_map *lock, int read) { unsigned long flags; int ret = 0; @@ -4294,7 +4300,7 @@ void lockdep_reset_lock(struct lockdep_map *lock) * If the class exists we look it up and zap it: */ class = look_up_lock_class(lock, j); - if (!IS_ERR_OR_NULL(class)) + if (class) zap_class(class); } /* @@ -4490,6 +4496,7 @@ retry: if (!unlock) if (read_trylock(&tasklist_lock)) unlock = 1; + touch_nmi_watchdog(); } while_each_thread(g, p); pr_warn("\n"); diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c index f24582d4dad3..6850ffd69125 100644 --- a/kernel/locking/locktorture.c +++ b/kernel/locking/locktorture.c @@ -77,10 +77,6 @@ struct lock_stress_stats { long n_lock_acquired; }; -int torture_runnable = IS_ENABLED(MODULE); -module_param(torture_runnable, int, 0444); -MODULE_PARM_DESC(torture_runnable, "Start locktorture at module init"); - /* Forward reference. */ static void lock_torture_cleanup(void); @@ -130,10 +126,8 @@ static void torture_lock_busted_write_delay(struct torture_random_state *trsp) if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 2000 * longdelay_ms))) mdelay(longdelay_ms); -#ifdef CONFIG_PREEMPT if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) - preempt_schedule(); /* Allow test to be preempted. */ -#endif + torture_preempt_schedule(); /* Allow test to be preempted. */ } static void torture_lock_busted_write_unlock(void) @@ -179,10 +173,8 @@ static void torture_spin_lock_write_delay(struct torture_random_state *trsp) if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 2 * shortdelay_us))) udelay(shortdelay_us); -#ifdef CONFIG_PREEMPT if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) - preempt_schedule(); /* Allow test to be preempted. */ -#endif + torture_preempt_schedule(); /* Allow test to be preempted. */ } static void torture_spin_lock_write_unlock(void) __releases(torture_spinlock) @@ -352,10 +344,8 @@ static void torture_mutex_delay(struct torture_random_state *trsp) mdelay(longdelay_ms * 5); else mdelay(longdelay_ms / 5); -#ifdef CONFIG_PREEMPT if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) - preempt_schedule(); /* Allow test to be preempted. */ -#endif + torture_preempt_schedule(); /* Allow test to be preempted. */ } static void torture_mutex_unlock(void) __releases(torture_mutex) @@ -507,10 +497,8 @@ static void torture_rtmutex_delay(struct torture_random_state *trsp) if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 2 * shortdelay_us))) udelay(shortdelay_us); -#ifdef CONFIG_PREEMPT if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) - preempt_schedule(); /* Allow test to be preempted. */ -#endif + torture_preempt_schedule(); /* Allow test to be preempted. */ } static void torture_rtmutex_unlock(void) __releases(torture_rtmutex) @@ -547,10 +535,8 @@ static void torture_rwsem_write_delay(struct torture_random_state *trsp) mdelay(longdelay_ms * 10); else mdelay(longdelay_ms / 10); -#ifdef CONFIG_PREEMPT if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) - preempt_schedule(); /* Allow test to be preempted. */ -#endif + torture_preempt_schedule(); /* Allow test to be preempted. */ } static void torture_rwsem_up_write(void) __releases(torture_rwsem) @@ -570,14 +556,12 @@ static void torture_rwsem_read_delay(struct torture_random_state *trsp) /* We want a long delay occasionally to force massive contention. */ if (!(torture_random(trsp) % - (cxt.nrealwriters_stress * 2000 * longdelay_ms))) + (cxt.nrealreaders_stress * 2000 * longdelay_ms))) mdelay(longdelay_ms * 2); else mdelay(longdelay_ms / 2); -#ifdef CONFIG_PREEMPT if (!(torture_random(trsp) % (cxt.nrealreaders_stress * 20000))) - preempt_schedule(); /* Allow test to be preempted. */ -#endif + torture_preempt_schedule(); /* Allow test to be preempted. */ } static void torture_rwsem_up_read(void) __releases(torture_rwsem) @@ -715,8 +699,7 @@ static void __torture_print_stats(char *page, { bool fail = 0; int i, n_stress; - long max = 0; - long min = statp[0].n_lock_acquired; + long max = 0, min = statp ? statp[0].n_lock_acquired : 0; long long sum = 0; n_stress = write ? cxt.nrealwriters_stress : cxt.nrealreaders_stress; @@ -823,7 +806,7 @@ static void lock_torture_cleanup(void) * such, only perform the underlying torture-specific cleanups, * and avoid anything related to locktorture. */ - if (!cxt.lwsa) + if (!cxt.lwsa && !cxt.lrsa) goto end; if (writer_tasks) { @@ -879,7 +862,7 @@ static int __init lock_torture_init(void) &percpu_rwsem_lock_ops, }; - if (!torture_init_begin(torture_type, verbose, &torture_runnable)) + if (!torture_init_begin(torture_type, verbose)) return -EBUSY; /* Process args and tell the world that the torturer is on the job. */ @@ -898,6 +881,13 @@ static int __init lock_torture_init(void) firsterr = -EINVAL; goto unwind; } + + if (nwriters_stress == 0 && nreaders_stress == 0) { + pr_alert("lock-torture: must run at least one locking thread\n"); + firsterr = -EINVAL; + goto unwind; + } + if (cxt.cur_ops->init) cxt.cur_ops->init(); @@ -921,17 +911,19 @@ static int __init lock_torture_init(void) #endif /* Initialize the statistics so that each run gets its own numbers. */ + if (nwriters_stress) { + lock_is_write_held = 0; + cxt.lwsa = kmalloc(sizeof(*cxt.lwsa) * cxt.nrealwriters_stress, GFP_KERNEL); + if (cxt.lwsa == NULL) { + VERBOSE_TOROUT_STRING("cxt.lwsa: Out of memory"); + firsterr = -ENOMEM; + goto unwind; + } - lock_is_write_held = 0; - cxt.lwsa = kmalloc(sizeof(*cxt.lwsa) * cxt.nrealwriters_stress, GFP_KERNEL); - if (cxt.lwsa == NULL) { - VERBOSE_TOROUT_STRING("cxt.lwsa: Out of memory"); - firsterr = -ENOMEM; - goto unwind; - } - for (i = 0; i < cxt.nrealwriters_stress; i++) { - cxt.lwsa[i].n_lock_fail = 0; - cxt.lwsa[i].n_lock_acquired = 0; + for (i = 0; i < cxt.nrealwriters_stress; i++) { + cxt.lwsa[i].n_lock_fail = 0; + cxt.lwsa[i].n_lock_acquired = 0; + } } if (cxt.cur_ops->readlock) { @@ -948,19 +940,21 @@ static int __init lock_torture_init(void) cxt.nrealreaders_stress = cxt.nrealwriters_stress; } - lock_is_read_held = 0; - cxt.lrsa = kmalloc(sizeof(*cxt.lrsa) * cxt.nrealreaders_stress, GFP_KERNEL); - if (cxt.lrsa == NULL) { - VERBOSE_TOROUT_STRING("cxt.lrsa: Out of memory"); - firsterr = -ENOMEM; - kfree(cxt.lwsa); - cxt.lwsa = NULL; - goto unwind; - } - - for (i = 0; i < cxt.nrealreaders_stress; i++) { - cxt.lrsa[i].n_lock_fail = 0; - cxt.lrsa[i].n_lock_acquired = 0; + if (nreaders_stress) { + lock_is_read_held = 0; + cxt.lrsa = kmalloc(sizeof(*cxt.lrsa) * cxt.nrealreaders_stress, GFP_KERNEL); + if (cxt.lrsa == NULL) { + VERBOSE_TOROUT_STRING("cxt.lrsa: Out of memory"); + firsterr = -ENOMEM; + kfree(cxt.lwsa); + cxt.lwsa = NULL; + goto unwind; + } + + for (i = 0; i < cxt.nrealreaders_stress; i++) { + cxt.lrsa[i].n_lock_fail = 0; + cxt.lrsa[i].n_lock_acquired = 0; + } } } @@ -990,12 +984,14 @@ static int __init lock_torture_init(void) goto unwind; } - writer_tasks = kzalloc(cxt.nrealwriters_stress * sizeof(writer_tasks[0]), - GFP_KERNEL); - if (writer_tasks == NULL) { - VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory"); - firsterr = -ENOMEM; - goto unwind; + if (nwriters_stress) { + writer_tasks = kzalloc(cxt.nrealwriters_stress * sizeof(writer_tasks[0]), + GFP_KERNEL); + if (writer_tasks == NULL) { + VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory"); + firsterr = -ENOMEM; + goto unwind; + } } if (cxt.cur_ops->readlock) { diff --git a/kernel/locking/qspinlock.c b/kernel/locking/qspinlock.c index 294294c71ba4..38ece035039e 100644 --- a/kernel/locking/qspinlock.c +++ b/kernel/locking/qspinlock.c @@ -170,7 +170,7 @@ static __always_inline void clear_pending_set_locked(struct qspinlock *lock) * @tail : The new queue tail code word * Return: The previous queue tail code word * - * xchg(lock, tail) + * xchg(lock, tail), which heads an address dependency * * p,*,* -> n,*,* ; prev = xchg(lock, node) */ @@ -409,13 +409,11 @@ queue: if (old & _Q_TAIL_MASK) { prev = decode_tail(old); /* - * The above xchg_tail() is also a load of @lock which generates, - * through decode_tail(), a pointer. - * - * The address dependency matches the RELEASE of xchg_tail() - * such that the access to @prev must happen after. + * The above xchg_tail() is also a load of @lock which + * generates, through decode_tail(), a pointer. The address + * dependency matches the RELEASE of xchg_tail() such that + * the subsequent access to @prev happens after. */ - smp_read_barrier_depends(); WRITE_ONCE(prev->next, node); diff --git a/kernel/module.c b/kernel/module.c index 601494d4b7ea..1d65b2cc4f80 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2863,6 +2863,15 @@ static int check_modinfo_livepatch(struct module *mod, struct load_info *info) } #endif /* CONFIG_LIVEPATCH */ +static void check_modinfo_retpoline(struct module *mod, struct load_info *info) +{ + if (retpoline_module_ok(get_modinfo(info, "retpoline"))) + return; + + pr_warn("%s: loading module not compiled with retpoline compiler.\n", + mod->name); +} + /* Sets info->hdr and info->len. */ static int copy_module_from_user(const void __user *umod, unsigned long len, struct load_info *info) @@ -3029,6 +3038,8 @@ static int check_modinfo(struct module *mod, struct load_info *info, int flags) add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK); } + check_modinfo_retpoline(mod, info); + if (get_modinfo(info, "staging")) { add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK); pr_warn("%s: module is from the staging directory, the quality " diff --git a/kernel/padata.c b/kernel/padata.c index 57c0074d50cc..d568cc56405f 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 /* * padata.c - generic interface to process data streams in parallel * diff --git a/kernel/pid.c b/kernel/pid.c index 1e8bb6550ec4..5d30c87e3c42 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -41,7 +41,19 @@ #include <linux/sched/task.h> #include <linux/idr.h> -struct pid init_struct_pid = INIT_STRUCT_PID; +struct pid init_struct_pid = { + .count = ATOMIC_INIT(1), + .tasks = { + { .first = NULL }, + { .first = NULL }, + { .first = NULL }, + }, + .level = 0, + .numbers = { { + .nr = 0, + .ns = &init_pid_ns, + }, } +}; int pid_max = PID_MAX_DEFAULT; diff --git a/kernel/power/main.c b/kernel/power/main.c index 3a2ca9066583..705c2366dafe 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -22,6 +22,35 @@ DEFINE_MUTEX(pm_mutex); #ifdef CONFIG_PM_SLEEP +void lock_system_sleep(void) +{ + current->flags |= PF_FREEZER_SKIP; + mutex_lock(&pm_mutex); +} +EXPORT_SYMBOL_GPL(lock_system_sleep); + +void unlock_system_sleep(void) +{ + /* + * Don't use freezer_count() because we don't want the call to + * try_to_freeze() here. + * + * Reason: + * Fundamentally, we just don't need it, because freezing condition + * doesn't come into effect until we release the pm_mutex lock, + * since the freezer always works with pm_mutex held. + * + * More importantly, in the case of hibernation, + * unlock_system_sleep() gets called in snapshot_read() and + * snapshot_write() when the freezing condition is still in effect. + * Which means, if we use try_to_freeze() here, it would make them + * enter the refrigerator, thus causing hibernation to lockup. + */ + current->flags &= ~PF_FREEZER_SKIP; + mutex_unlock(&pm_mutex); +} +EXPORT_SYMBOL_GPL(unlock_system_sleep); + /* Routines for PM-transition notifications */ static BLOCKING_NOTIFIER_HEAD(pm_chain_head); diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index bce0464524d8..3d37c279c090 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -1645,8 +1645,7 @@ static unsigned long free_unnecessary_pages(void) * [number of saveable pages] - [number of pages that can be freed in theory] * * where the second term is the sum of (1) reclaimable slab pages, (2) active - * and (3) inactive anonymous pages, (4) active and (5) inactive file pages, - * minus mapped file pages. + * and (3) inactive anonymous pages, (4) active and (5) inactive file pages. */ static unsigned long minimum_image_size(unsigned long saveable) { @@ -1656,8 +1655,7 @@ static unsigned long minimum_image_size(unsigned long saveable) + global_node_page_state(NR_ACTIVE_ANON) + global_node_page_state(NR_INACTIVE_ANON) + global_node_page_state(NR_ACTIVE_FILE) - + global_node_page_state(NR_INACTIVE_FILE) - - global_node_page_state(NR_FILE_MAPPED); + + global_node_page_state(NR_INACTIVE_FILE); return saveable <= size ? 0 : saveable - size; } diff --git a/kernel/power/swap.c b/kernel/power/swap.c index 293ead59eccc..11b4282c2d20 100644 --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -240,7 +240,7 @@ static void hib_init_batch(struct hib_bio_batch *hb) static void hib_end_io(struct bio *bio) { struct hib_bio_batch *hb = bio->bi_private; - struct page *page = bio->bi_io_vec[0].bv_page; + struct page *page = bio_first_page_all(bio); if (bio->bi_status) { pr_alert("Read-error on swap-device (%u:%u:%Lu)\n", @@ -879,7 +879,7 @@ out_clean: * space avaiable from the resume partition. */ -static int enough_swap(unsigned int nr_pages, unsigned int flags) +static int enough_swap(unsigned int nr_pages) { unsigned int free_swap = count_swap_pages(root_swap, 1); unsigned int required; @@ -915,7 +915,7 @@ int swsusp_write(unsigned int flags) return error; } if (flags & SF_NOCOMPRESS_MODE) { - if (!enough_swap(pages, flags)) { + if (!enough_swap(pages)) { pr_err("Not enough free swap\n"); error = -ENOSPC; goto out_finish; diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index b9006617710f..c2e713f6ae2e 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -920,10 +920,10 @@ static loff_t devkmsg_llseek(struct file *file, loff_t offset, int whence) return ret; } -static unsigned int devkmsg_poll(struct file *file, poll_table *wait) +static __poll_t devkmsg_poll(struct file *file, poll_table *wait) { struct devkmsg_user *user = file->private_data; - int ret = 0; + __poll_t ret = 0; if (!user) return POLLERR|POLLNVAL; diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 84b1367935e4..5e1d713c8e61 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -659,7 +659,7 @@ static int ptrace_getsiginfo(struct task_struct *child, siginfo_t *info) if (lock_task_sighand(child, &flags)) { error = -EINVAL; if (likely(child->last_siginfo != NULL)) { - *info = *child->last_siginfo; + copy_siginfo(info, child->last_siginfo); error = 0; } unlock_task_sighand(child, &flags); @@ -675,7 +675,7 @@ static int ptrace_setsiginfo(struct task_struct *child, const siginfo_t *info) if (lock_task_sighand(child, &flags)) { error = -EINVAL; if (likely(child->last_siginfo != NULL)) { - *child->last_siginfo = *info; + copy_siginfo(child->last_siginfo, info); error = 0; } unlock_task_sighand(child, &flags); @@ -1092,6 +1092,10 @@ int ptrace_request(struct task_struct *child, long request, ret = seccomp_get_filter(child, addr, datavp); break; + case PTRACE_SECCOMP_GET_METADATA: + ret = seccomp_get_metadata(child, addr, datavp); + break; + default: break; } @@ -1226,7 +1230,6 @@ int compat_ptrace_request(struct task_struct *child, compat_long_t request, break; case PTRACE_SETSIGINFO: - memset(&siginfo, 0, sizeof siginfo); if (copy_siginfo_from_user32( &siginfo, (struct compat_siginfo __user *) datap)) ret = -EFAULT; diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h index 59c471de342a..6334f2c1abd0 100644 --- a/kernel/rcu/rcu.h +++ b/kernel/rcu/rcu.h @@ -30,31 +30,8 @@ #define RCU_TRACE(stmt) #endif /* #else #ifdef CONFIG_RCU_TRACE */ -/* - * Process-level increment to ->dynticks_nesting field. This allows for - * architectures that use half-interrupts and half-exceptions from - * process context. - * - * DYNTICK_TASK_NEST_MASK defines a field of width DYNTICK_TASK_NEST_WIDTH - * that counts the number of process-based reasons why RCU cannot - * consider the corresponding CPU to be idle, and DYNTICK_TASK_NEST_VALUE - * is the value used to increment or decrement this field. - * - * The rest of the bits could in principle be used to count interrupts, - * but this would mean that a negative-one value in the interrupt - * field could incorrectly zero out the DYNTICK_TASK_NEST_MASK field. - * We therefore provide a two-bit guard field defined by DYNTICK_TASK_MASK - * that is set to DYNTICK_TASK_FLAG upon initial exit from idle. - * The DYNTICK_TASK_EXIT_IDLE value is thus the combined value used upon - * initial exit from idle. - */ -#define DYNTICK_TASK_NEST_WIDTH 7 -#define DYNTICK_TASK_NEST_VALUE ((LLONG_MAX >> DYNTICK_TASK_NEST_WIDTH) + 1) -#define DYNTICK_TASK_NEST_MASK (LLONG_MAX - DYNTICK_TASK_NEST_VALUE + 1) -#define DYNTICK_TASK_FLAG ((DYNTICK_TASK_NEST_VALUE / 8) * 2) -#define DYNTICK_TASK_MASK ((DYNTICK_TASK_NEST_VALUE / 8) * 3) -#define DYNTICK_TASK_EXIT_IDLE (DYNTICK_TASK_NEST_VALUE + \ - DYNTICK_TASK_FLAG) +/* Offset to allow for unmatched rcu_irq_{enter,exit}(). */ +#define DYNTICK_IRQ_NONIDLE ((LONG_MAX / 2) + 1) /* diff --git a/kernel/rcu/rcuperf.c b/kernel/rcu/rcuperf.c index 1f87a02c3399..d1ebdf9868bb 100644 --- a/kernel/rcu/rcuperf.c +++ b/kernel/rcu/rcuperf.c @@ -106,10 +106,6 @@ static int rcu_perf_writer_state; #define MAX_MEAS 10000 #define MIN_MEAS 100 -static int perf_runnable = IS_ENABLED(MODULE); -module_param(perf_runnable, int, 0444); -MODULE_PARM_DESC(perf_runnable, "Start rcuperf at boot"); - /* * Operations vector for selecting different types of tests. */ @@ -646,7 +642,7 @@ rcu_perf_init(void) &tasks_ops, }; - if (!torture_init_begin(perf_type, verbose, &perf_runnable)) + if (!torture_init_begin(perf_type, verbose)) return -EBUSY; /* Process args and tell the world that the perf'er is on the job. */ diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 74f6b0146b98..308e6fdbced8 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -187,10 +187,6 @@ static const char *rcu_torture_writer_state_getname(void) return rcu_torture_writer_state_names[i]; } -static int torture_runnable = IS_ENABLED(MODULE); -module_param(torture_runnable, int, 0444); -MODULE_PARM_DESC(torture_runnable, "Start rcutorture at boot"); - #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) #define rcu_can_boost() 1 #else /* #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ @@ -315,11 +311,9 @@ static void rcu_read_delay(struct torture_random_state *rrsp) } if (!(torture_random(rrsp) % (nrealreaders * 2 * shortdelay_us))) udelay(shortdelay_us); -#ifdef CONFIG_PREEMPT if (!preempt_count() && - !(torture_random(rrsp) % (nrealreaders * 20000))) - preempt_schedule(); /* No QS if preempt_disable() in effect */ -#endif + !(torture_random(rrsp) % (nrealreaders * 500))) + torture_preempt_schedule(); /* QS only if preemptible. */ } static void rcu_torture_read_unlock(int idx) __releases(RCU) @@ -1731,7 +1725,7 @@ rcu_torture_init(void) &sched_ops, &tasks_ops, }; - if (!torture_init_begin(torture_type, verbose, &torture_runnable)) + if (!torture_init_begin(torture_type, verbose)) return -EBUSY; /* Process args and tell the world that the torturer is on the job. */ diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c index 6d5880089ff6..d5cea81378cc 100644 --- a/kernel/rcu/srcutree.c +++ b/kernel/rcu/srcutree.c @@ -53,6 +53,33 @@ static void srcu_invoke_callbacks(struct work_struct *work); static void srcu_reschedule(struct srcu_struct *sp, unsigned long delay); static void process_srcu(struct work_struct *work); +/* Wrappers for lock acquisition and release, see raw_spin_lock_rcu_node(). */ +#define spin_lock_rcu_node(p) \ +do { \ + spin_lock(&ACCESS_PRIVATE(p, lock)); \ + smp_mb__after_unlock_lock(); \ +} while (0) + +#define spin_unlock_rcu_node(p) spin_unlock(&ACCESS_PRIVATE(p, lock)) + +#define spin_lock_irq_rcu_node(p) \ +do { \ + spin_lock_irq(&ACCESS_PRIVATE(p, lock)); \ + smp_mb__after_unlock_lock(); \ +} while (0) + +#define spin_unlock_irq_rcu_node(p) \ + spin_unlock_irq(&ACCESS_PRIVATE(p, lock)) + +#define spin_lock_irqsave_rcu_node(p, flags) \ +do { \ + spin_lock_irqsave(&ACCESS_PRIVATE(p, lock), flags); \ + smp_mb__after_unlock_lock(); \ +} while (0) + +#define spin_unlock_irqrestore_rcu_node(p, flags) \ + spin_unlock_irqrestore(&ACCESS_PRIVATE(p, lock), flags) \ + /* * Initialize SRCU combining tree. Note that statically allocated * srcu_struct structures might already have srcu_read_lock() and @@ -77,7 +104,7 @@ static void init_srcu_struct_nodes(struct srcu_struct *sp, bool is_static) /* Each pass through this loop initializes one srcu_node structure. */ rcu_for_each_node_breadth_first(sp, snp) { - raw_spin_lock_init(&ACCESS_PRIVATE(snp, lock)); + spin_lock_init(&ACCESS_PRIVATE(snp, lock)); WARN_ON_ONCE(ARRAY_SIZE(snp->srcu_have_cbs) != ARRAY_SIZE(snp->srcu_data_have_cbs)); for (i = 0; i < ARRAY_SIZE(snp->srcu_have_cbs); i++) { @@ -111,7 +138,7 @@ static void init_srcu_struct_nodes(struct srcu_struct *sp, bool is_static) snp_first = sp->level[level]; for_each_possible_cpu(cpu) { sdp = per_cpu_ptr(sp->sda, cpu); - raw_spin_lock_init(&ACCESS_PRIVATE(sdp, lock)); + spin_lock_init(&ACCESS_PRIVATE(sdp, lock)); rcu_segcblist_init(&sdp->srcu_cblist); sdp->srcu_cblist_invoking = false; sdp->srcu_gp_seq_needed = sp->srcu_gp_seq; @@ -170,7 +197,7 @@ int __init_srcu_struct(struct srcu_struct *sp, const char *name, /* Don't re-initialize a lock while it is held. */ debug_check_no_locks_freed((void *)sp, sizeof(*sp)); lockdep_init_map(&sp->dep_map, name, key, 0); - raw_spin_lock_init(&ACCESS_PRIVATE(sp, lock)); + spin_lock_init(&ACCESS_PRIVATE(sp, lock)); return init_srcu_struct_fields(sp, false); } EXPORT_SYMBOL_GPL(__init_srcu_struct); @@ -187,7 +214,7 @@ EXPORT_SYMBOL_GPL(__init_srcu_struct); */ int init_srcu_struct(struct srcu_struct *sp) { - raw_spin_lock_init(&ACCESS_PRIVATE(sp, lock)); + spin_lock_init(&ACCESS_PRIVATE(sp, lock)); return init_srcu_struct_fields(sp, false); } EXPORT_SYMBOL_GPL(init_srcu_struct); @@ -210,13 +237,13 @@ static void check_init_srcu_struct(struct srcu_struct *sp) /* The smp_load_acquire() pairs with the smp_store_release(). */ if (!rcu_seq_state(smp_load_acquire(&sp->srcu_gp_seq_needed))) /*^^^*/ return; /* Already initialized. */ - raw_spin_lock_irqsave_rcu_node(sp, flags); + spin_lock_irqsave_rcu_node(sp, flags); if (!rcu_seq_state(sp->srcu_gp_seq_needed)) { - raw_spin_unlock_irqrestore_rcu_node(sp, flags); + spin_unlock_irqrestore_rcu_node(sp, flags); return; } init_srcu_struct_fields(sp, true); - raw_spin_unlock_irqrestore_rcu_node(sp, flags); + spin_unlock_irqrestore_rcu_node(sp, flags); } /* @@ -513,7 +540,7 @@ static void srcu_gp_end(struct srcu_struct *sp) mutex_lock(&sp->srcu_cb_mutex); /* End the current grace period. */ - raw_spin_lock_irq_rcu_node(sp); + spin_lock_irq_rcu_node(sp); idx = rcu_seq_state(sp->srcu_gp_seq); WARN_ON_ONCE(idx != SRCU_STATE_SCAN2); cbdelay = srcu_get_delay(sp); @@ -522,7 +549,7 @@ static void srcu_gp_end(struct srcu_struct *sp) gpseq = rcu_seq_current(&sp->srcu_gp_seq); if (ULONG_CMP_LT(sp->srcu_gp_seq_needed_exp, gpseq)) sp->srcu_gp_seq_needed_exp = gpseq; - raw_spin_unlock_irq_rcu_node(sp); + spin_unlock_irq_rcu_node(sp); mutex_unlock(&sp->srcu_gp_mutex); /* A new grace period can start at this point. But only one. */ @@ -530,7 +557,7 @@ static void srcu_gp_end(struct srcu_struct *sp) idx = rcu_seq_ctr(gpseq) % ARRAY_SIZE(snp->srcu_have_cbs); idxnext = (idx + 1) % ARRAY_SIZE(snp->srcu_have_cbs); rcu_for_each_node_breadth_first(sp, snp) { - raw_spin_lock_irq_rcu_node(snp); + spin_lock_irq_rcu_node(snp); cbs = false; if (snp >= sp->level[rcu_num_lvls - 1]) cbs = snp->srcu_have_cbs[idx] == gpseq; @@ -540,7 +567,7 @@ static void srcu_gp_end(struct srcu_struct *sp) snp->srcu_gp_seq_needed_exp = gpseq; mask = snp->srcu_data_have_cbs[idx]; snp->srcu_data_have_cbs[idx] = 0; - raw_spin_unlock_irq_rcu_node(snp); + spin_unlock_irq_rcu_node(snp); if (cbs) srcu_schedule_cbs_snp(sp, snp, mask, cbdelay); @@ -548,11 +575,11 @@ static void srcu_gp_end(struct srcu_struct *sp) if (!(gpseq & counter_wrap_check)) for (cpu = snp->grplo; cpu <= snp->grphi; cpu++) { sdp = per_cpu_ptr(sp->sda, cpu); - raw_spin_lock_irqsave_rcu_node(sdp, flags); + spin_lock_irqsave_rcu_node(sdp, flags); if (ULONG_CMP_GE(gpseq, sdp->srcu_gp_seq_needed + 100)) sdp->srcu_gp_seq_needed = gpseq; - raw_spin_unlock_irqrestore_rcu_node(sdp, flags); + spin_unlock_irqrestore_rcu_node(sdp, flags); } } @@ -560,17 +587,17 @@ static void srcu_gp_end(struct srcu_struct *sp) mutex_unlock(&sp->srcu_cb_mutex); /* Start a new grace period if needed. */ - raw_spin_lock_irq_rcu_node(sp); + spin_lock_irq_rcu_node(sp); gpseq = rcu_seq_current(&sp->srcu_gp_seq); if (!rcu_seq_state(gpseq) && ULONG_CMP_LT(gpseq, sp->srcu_gp_seq_needed)) { srcu_gp_start(sp); - raw_spin_unlock_irq_rcu_node(sp); + spin_unlock_irq_rcu_node(sp); /* Throttle expedited grace periods: Should be rare! */ srcu_reschedule(sp, rcu_seq_ctr(gpseq) & 0x3ff ? 0 : SRCU_INTERVAL); } else { - raw_spin_unlock_irq_rcu_node(sp); + spin_unlock_irq_rcu_node(sp); } } @@ -590,18 +617,18 @@ static void srcu_funnel_exp_start(struct srcu_struct *sp, struct srcu_node *snp, if (rcu_seq_done(&sp->srcu_gp_seq, s) || ULONG_CMP_GE(READ_ONCE(snp->srcu_gp_seq_needed_exp), s)) return; - raw_spin_lock_irqsave_rcu_node(snp, flags); + spin_lock_irqsave_rcu_node(snp, flags); if (ULONG_CMP_GE(snp->srcu_gp_seq_needed_exp, s)) { - raw_spin_unlock_irqrestore_rcu_node(snp, flags); + spin_unlock_irqrestore_rcu_node(snp, flags); return; } WRITE_ONCE(snp->srcu_gp_seq_needed_exp, s); - raw_spin_unlock_irqrestore_rcu_node(snp, flags); + spin_unlock_irqrestore_rcu_node(snp, flags); } - raw_spin_lock_irqsave_rcu_node(sp, flags); + spin_lock_irqsave_rcu_node(sp, flags); if (!ULONG_CMP_LT(sp->srcu_gp_seq_needed_exp, s)) sp->srcu_gp_seq_needed_exp = s; - raw_spin_unlock_irqrestore_rcu_node(sp, flags); + spin_unlock_irqrestore_rcu_node(sp, flags); } /* @@ -623,12 +650,12 @@ static void srcu_funnel_gp_start(struct srcu_struct *sp, struct srcu_data *sdp, for (; snp != NULL; snp = snp->srcu_parent) { if (rcu_seq_done(&sp->srcu_gp_seq, s) && snp != sdp->mynode) return; /* GP already done and CBs recorded. */ - raw_spin_lock_irqsave_rcu_node(snp, flags); + spin_lock_irqsave_rcu_node(snp, flags); if (ULONG_CMP_GE(snp->srcu_have_cbs[idx], s)) { snp_seq = snp->srcu_have_cbs[idx]; if (snp == sdp->mynode && snp_seq == s) snp->srcu_data_have_cbs[idx] |= sdp->grpmask; - raw_spin_unlock_irqrestore_rcu_node(snp, flags); + spin_unlock_irqrestore_rcu_node(snp, flags); if (snp == sdp->mynode && snp_seq != s) { srcu_schedule_cbs_sdp(sdp, do_norm ? SRCU_INTERVAL @@ -644,11 +671,11 @@ static void srcu_funnel_gp_start(struct srcu_struct *sp, struct srcu_data *sdp, snp->srcu_data_have_cbs[idx] |= sdp->grpmask; if (!do_norm && ULONG_CMP_LT(snp->srcu_gp_seq_needed_exp, s)) snp->srcu_gp_seq_needed_exp = s; - raw_spin_unlock_irqrestore_rcu_node(snp, flags); + spin_unlock_irqrestore_rcu_node(snp, flags); } /* Top of tree, must ensure the grace period will be started. */ - raw_spin_lock_irqsave_rcu_node(sp, flags); + spin_lock_irqsave_rcu_node(sp, flags); if (ULONG_CMP_LT(sp->srcu_gp_seq_needed, s)) { /* * Record need for grace period s. Pair with load @@ -667,7 +694,7 @@ static void srcu_funnel_gp_start(struct srcu_struct *sp, struct srcu_data *sdp, queue_delayed_work(system_power_efficient_wq, &sp->work, srcu_get_delay(sp)); } - raw_spin_unlock_irqrestore_rcu_node(sp, flags); + spin_unlock_irqrestore_rcu_node(sp, flags); } /* @@ -830,7 +857,7 @@ void __call_srcu(struct srcu_struct *sp, struct rcu_head *rhp, rhp->func = func; local_irq_save(flags); sdp = this_cpu_ptr(sp->sda); - raw_spin_lock_rcu_node(sdp); + spin_lock_rcu_node(sdp); rcu_segcblist_enqueue(&sdp->srcu_cblist, rhp, false); rcu_segcblist_advance(&sdp->srcu_cblist, rcu_seq_current(&sp->srcu_gp_seq)); @@ -844,7 +871,7 @@ void __call_srcu(struct srcu_struct *sp, struct rcu_head *rhp, sdp->srcu_gp_seq_needed_exp = s; needexp = true; } - raw_spin_unlock_irqrestore_rcu_node(sdp, flags); + spin_unlock_irqrestore_rcu_node(sdp, flags); if (needgp) srcu_funnel_gp_start(sp, sdp, s, do_norm); else if (needexp) @@ -900,7 +927,7 @@ static void __synchronize_srcu(struct srcu_struct *sp, bool do_norm) /* * Make sure that later code is ordered after the SRCU grace - * period. This pairs with the raw_spin_lock_irq_rcu_node() + * period. This pairs with the spin_lock_irq_rcu_node() * in srcu_invoke_callbacks(). Unlike Tree RCU, this is needed * because the current CPU might have been totally uninvolved with * (and thus unordered against) that grace period. @@ -1024,7 +1051,7 @@ void srcu_barrier(struct srcu_struct *sp) */ for_each_possible_cpu(cpu) { sdp = per_cpu_ptr(sp->sda, cpu); - raw_spin_lock_irq_rcu_node(sdp); + spin_lock_irq_rcu_node(sdp); atomic_inc(&sp->srcu_barrier_cpu_cnt); sdp->srcu_barrier_head.func = srcu_barrier_cb; debug_rcu_head_queue(&sdp->srcu_barrier_head); @@ -1033,7 +1060,7 @@ void srcu_barrier(struct srcu_struct *sp) debug_rcu_head_unqueue(&sdp->srcu_barrier_head); atomic_dec(&sp->srcu_barrier_cpu_cnt); } - raw_spin_unlock_irq_rcu_node(sdp); + spin_unlock_irq_rcu_node(sdp); } /* Remove the initial count, at which point reaching zero can happen. */ @@ -1082,17 +1109,17 @@ static void srcu_advance_state(struct srcu_struct *sp) */ idx = rcu_seq_state(smp_load_acquire(&sp->srcu_gp_seq)); /* ^^^ */ if (idx == SRCU_STATE_IDLE) { - raw_spin_lock_irq_rcu_node(sp); + spin_lock_irq_rcu_node(sp); if (ULONG_CMP_GE(sp->srcu_gp_seq, sp->srcu_gp_seq_needed)) { WARN_ON_ONCE(rcu_seq_state(sp->srcu_gp_seq)); - raw_spin_unlock_irq_rcu_node(sp); + spin_unlock_irq_rcu_node(sp); mutex_unlock(&sp->srcu_gp_mutex); return; } idx = rcu_seq_state(READ_ONCE(sp->srcu_gp_seq)); if (idx == SRCU_STATE_IDLE) srcu_gp_start(sp); - raw_spin_unlock_irq_rcu_node(sp); + spin_unlock_irq_rcu_node(sp); if (idx != SRCU_STATE_IDLE) { mutex_unlock(&sp->srcu_gp_mutex); return; /* Someone else started the grace period. */ @@ -1141,19 +1168,19 @@ static void srcu_invoke_callbacks(struct work_struct *work) sdp = container_of(work, struct srcu_data, work.work); sp = sdp->sp; rcu_cblist_init(&ready_cbs); - raw_spin_lock_irq_rcu_node(sdp); + spin_lock_irq_rcu_node(sdp); rcu_segcblist_advance(&sdp->srcu_cblist, rcu_seq_current(&sp->srcu_gp_seq)); if (sdp->srcu_cblist_invoking || !rcu_segcblist_ready_cbs(&sdp->srcu_cblist)) { - raw_spin_unlock_irq_rcu_node(sdp); + spin_unlock_irq_rcu_node(sdp); return; /* Someone else on the job or nothing to do. */ } /* We are on the job! Extract and invoke ready callbacks. */ sdp->srcu_cblist_invoking = true; rcu_segcblist_extract_done_cbs(&sdp->srcu_cblist, &ready_cbs); - raw_spin_unlock_irq_rcu_node(sdp); + spin_unlock_irq_rcu_node(sdp); rhp = rcu_cblist_dequeue(&ready_cbs); for (; rhp != NULL; rhp = rcu_cblist_dequeue(&ready_cbs)) { debug_rcu_head_unqueue(rhp); @@ -1166,13 +1193,13 @@ static void srcu_invoke_callbacks(struct work_struct *work) * Update counts, accelerate new callbacks, and if needed, * schedule another round of callback invocation. */ - raw_spin_lock_irq_rcu_node(sdp); + spin_lock_irq_rcu_node(sdp); rcu_segcblist_insert_count(&sdp->srcu_cblist, &ready_cbs); (void)rcu_segcblist_accelerate(&sdp->srcu_cblist, rcu_seq_snap(&sp->srcu_gp_seq)); sdp->srcu_cblist_invoking = false; more = rcu_segcblist_ready_cbs(&sdp->srcu_cblist); - raw_spin_unlock_irq_rcu_node(sdp); + spin_unlock_irq_rcu_node(sdp); if (more) srcu_schedule_cbs_sdp(sdp, 0); } @@ -1185,7 +1212,7 @@ static void srcu_reschedule(struct srcu_struct *sp, unsigned long delay) { bool pushgp = true; - raw_spin_lock_irq_rcu_node(sp); + spin_lock_irq_rcu_node(sp); if (ULONG_CMP_GE(sp->srcu_gp_seq, sp->srcu_gp_seq_needed)) { if (!WARN_ON_ONCE(rcu_seq_state(sp->srcu_gp_seq))) { /* All requests fulfilled, time to go idle. */ @@ -1195,7 +1222,7 @@ static void srcu_reschedule(struct srcu_struct *sp, unsigned long delay) /* Outstanding request and no GP. Start one. */ srcu_gp_start(sp); } - raw_spin_unlock_irq_rcu_node(sp); + spin_unlock_irq_rcu_node(sp); if (pushgp) queue_delayed_work(system_power_efficient_wq, &sp->work, delay); diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index f9c0ca2ccf0c..491bdf39f276 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -265,25 +265,12 @@ void rcu_bh_qs(void) #endif static DEFINE_PER_CPU(struct rcu_dynticks, rcu_dynticks) = { - .dynticks_nesting = DYNTICK_TASK_EXIT_IDLE, + .dynticks_nesting = 1, + .dynticks_nmi_nesting = DYNTICK_IRQ_NONIDLE, .dynticks = ATOMIC_INIT(RCU_DYNTICK_CTRL_CTR), }; /* - * There's a few places, currently just in the tracing infrastructure, - * that uses rcu_irq_enter() to make sure RCU is watching. But there's - * a small location where that will not even work. In those cases - * rcu_irq_enter_disabled() needs to be checked to make sure rcu_irq_enter() - * can be called. - */ -static DEFINE_PER_CPU(bool, disable_rcu_irq_enter); - -bool rcu_irq_enter_disabled(void) -{ - return this_cpu_read(disable_rcu_irq_enter); -} - -/* * Record entry into an extended quiescent state. This is only to be * called when not already in an extended quiescent state. */ @@ -762,68 +749,39 @@ cpu_needs_another_gp(struct rcu_state *rsp, struct rcu_data *rdp) } /* - * rcu_eqs_enter_common - current CPU is entering an extended quiescent state + * Enter an RCU extended quiescent state, which can be either the + * idle loop or adaptive-tickless usermode execution. * - * Enter idle, doing appropriate accounting. The caller must have - * disabled interrupts. + * We crowbar the ->dynticks_nmi_nesting field to zero to allow for + * the possibility of usermode upcalls having messed up our count + * of interrupt nesting level during the prior busy period. */ -static void rcu_eqs_enter_common(bool user) +static void rcu_eqs_enter(bool user) { struct rcu_state *rsp; struct rcu_data *rdp; - struct rcu_dynticks *rdtp = this_cpu_ptr(&rcu_dynticks); + struct rcu_dynticks *rdtp; - lockdep_assert_irqs_disabled(); - trace_rcu_dyntick(TPS("Start"), rdtp->dynticks_nesting, 0); - if (IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && - !user && !is_idle_task(current)) { - struct task_struct *idle __maybe_unused = - idle_task(smp_processor_id()); - - trace_rcu_dyntick(TPS("Error on entry: not idle task"), rdtp->dynticks_nesting, 0); - rcu_ftrace_dump(DUMP_ORIG); - WARN_ONCE(1, "Current pid: %d comm: %s / Idle pid: %d comm: %s", - current->pid, current->comm, - idle->pid, idle->comm); /* must be idle task! */ + rdtp = this_cpu_ptr(&rcu_dynticks); + WRITE_ONCE(rdtp->dynticks_nmi_nesting, 0); + WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && + rdtp->dynticks_nesting == 0); + if (rdtp->dynticks_nesting != 1) { + rdtp->dynticks_nesting--; + return; } + + lockdep_assert_irqs_disabled(); + trace_rcu_dyntick(TPS("Start"), rdtp->dynticks_nesting, 0, rdtp->dynticks); + WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !user && !is_idle_task(current)); for_each_rcu_flavor(rsp) { rdp = this_cpu_ptr(rsp->rda); do_nocb_deferred_wakeup(rdp); } rcu_prepare_for_idle(); - __this_cpu_inc(disable_rcu_irq_enter); - rdtp->dynticks_nesting = 0; /* Breaks tracing momentarily. */ - rcu_dynticks_eqs_enter(); /* After this, tracing works again. */ - __this_cpu_dec(disable_rcu_irq_enter); + WRITE_ONCE(rdtp->dynticks_nesting, 0); /* Avoid irq-access tearing. */ + rcu_dynticks_eqs_enter(); rcu_dynticks_task_enter(); - - /* - * It is illegal to enter an extended quiescent state while - * in an RCU read-side critical section. - */ - RCU_LOCKDEP_WARN(lock_is_held(&rcu_lock_map), - "Illegal idle entry in RCU read-side critical section."); - RCU_LOCKDEP_WARN(lock_is_held(&rcu_bh_lock_map), - "Illegal idle entry in RCU-bh read-side critical section."); - RCU_LOCKDEP_WARN(lock_is_held(&rcu_sched_lock_map), - "Illegal idle entry in RCU-sched read-side critical section."); -} - -/* - * Enter an RCU extended quiescent state, which can be either the - * idle loop or adaptive-tickless usermode execution. - */ -static void rcu_eqs_enter(bool user) -{ - struct rcu_dynticks *rdtp; - - rdtp = this_cpu_ptr(&rcu_dynticks); - WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && - (rdtp->dynticks_nesting & DYNTICK_TASK_NEST_MASK) == 0); - if ((rdtp->dynticks_nesting & DYNTICK_TASK_NEST_MASK) == DYNTICK_TASK_NEST_VALUE) - rcu_eqs_enter_common(user); - else - rdtp->dynticks_nesting -= DYNTICK_TASK_NEST_VALUE; } /** @@ -834,10 +792,6 @@ static void rcu_eqs_enter(bool user) * critical sections can occur in irq handlers in idle, a possibility * handled by irq_enter() and irq_exit().) * - * We crowbar the ->dynticks_nesting field to zero to allow for - * the possibility of usermode upcalls having messed up our count - * of interrupt nesting level during the prior busy period. - * * If you add or remove a call to rcu_idle_enter(), be sure to test with * CONFIG_RCU_EQS_DEBUG=y. */ @@ -867,6 +821,46 @@ void rcu_user_enter(void) #endif /* CONFIG_NO_HZ_FULL */ /** + * rcu_nmi_exit - inform RCU of exit from NMI context + * + * If we are returning from the outermost NMI handler that interrupted an + * RCU-idle period, update rdtp->dynticks and rdtp->dynticks_nmi_nesting + * to let the RCU grace-period handling know that the CPU is back to + * being RCU-idle. + * + * If you add or remove a call to rcu_nmi_exit(), be sure to test + * with CONFIG_RCU_EQS_DEBUG=y. + */ +void rcu_nmi_exit(void) +{ + struct rcu_dynticks *rdtp = this_cpu_ptr(&rcu_dynticks); + + /* + * Check for ->dynticks_nmi_nesting underflow and bad ->dynticks. + * (We are exiting an NMI handler, so RCU better be paying attention + * to us!) + */ + WARN_ON_ONCE(rdtp->dynticks_nmi_nesting <= 0); + WARN_ON_ONCE(rcu_dynticks_curr_cpu_in_eqs()); + + /* + * If the nesting level is not 1, the CPU wasn't RCU-idle, so + * leave it in non-RCU-idle state. + */ + if (rdtp->dynticks_nmi_nesting != 1) { + trace_rcu_dyntick(TPS("--="), rdtp->dynticks_nmi_nesting, rdtp->dynticks_nmi_nesting - 2, rdtp->dynticks); + WRITE_ONCE(rdtp->dynticks_nmi_nesting, /* No store tearing. */ + rdtp->dynticks_nmi_nesting - 2); + return; + } + + /* This NMI interrupted an RCU-idle CPU, restore RCU-idleness. */ + trace_rcu_dyntick(TPS("Startirq"), rdtp->dynticks_nmi_nesting, 0, rdtp->dynticks); + WRITE_ONCE(rdtp->dynticks_nmi_nesting, 0); /* Avoid store tearing. */ + rcu_dynticks_eqs_enter(); +} + +/** * rcu_irq_exit - inform RCU that current CPU is exiting irq towards idle * * Exit from an interrupt handler, which might possibly result in entering @@ -875,8 +869,8 @@ void rcu_user_enter(void) * * This code assumes that the idle loop never does anything that might * result in unbalanced calls to irq_enter() and irq_exit(). If your - * architecture violates this assumption, RCU will give you what you - * deserve, good and hard. But very infrequently and irreproducibly. + * architecture's idle loop violates this assumption, RCU will give you what + * you deserve, good and hard. But very infrequently and irreproducibly. * * Use things like work queues to work around this limitation. * @@ -887,23 +881,14 @@ void rcu_user_enter(void) */ void rcu_irq_exit(void) { - struct rcu_dynticks *rdtp; + struct rcu_dynticks *rdtp = this_cpu_ptr(&rcu_dynticks); lockdep_assert_irqs_disabled(); - rdtp = this_cpu_ptr(&rcu_dynticks); - - /* Page faults can happen in NMI handlers, so check... */ - if (rdtp->dynticks_nmi_nesting) - return; - - WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && - rdtp->dynticks_nesting < 1); - if (rdtp->dynticks_nesting <= 1) { - rcu_eqs_enter_common(true); - } else { - trace_rcu_dyntick(TPS("--="), rdtp->dynticks_nesting, rdtp->dynticks_nesting - 1); - rdtp->dynticks_nesting--; - } + if (rdtp->dynticks_nmi_nesting == 1) + rcu_prepare_for_idle(); + rcu_nmi_exit(); + if (rdtp->dynticks_nmi_nesting == 0) + rcu_dynticks_task_enter(); } /* @@ -922,55 +907,33 @@ void rcu_irq_exit_irqson(void) } /* - * rcu_eqs_exit_common - current CPU moving away from extended quiescent state - * - * If the new value of the ->dynticks_nesting counter was previously zero, - * we really have exited idle, and must do the appropriate accounting. - * The caller must have disabled interrupts. - */ -static void rcu_eqs_exit_common(long long oldval, int user) -{ - RCU_TRACE(struct rcu_dynticks *rdtp = this_cpu_ptr(&rcu_dynticks);) - - rcu_dynticks_task_exit(); - rcu_dynticks_eqs_exit(); - rcu_cleanup_after_idle(); - trace_rcu_dyntick(TPS("End"), oldval, rdtp->dynticks_nesting); - if (IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && - !user && !is_idle_task(current)) { - struct task_struct *idle __maybe_unused = - idle_task(smp_processor_id()); - - trace_rcu_dyntick(TPS("Error on exit: not idle task"), - oldval, rdtp->dynticks_nesting); - rcu_ftrace_dump(DUMP_ORIG); - WARN_ONCE(1, "Current pid: %d comm: %s / Idle pid: %d comm: %s", - current->pid, current->comm, - idle->pid, idle->comm); /* must be idle task! */ - } -} - -/* * Exit an RCU extended quiescent state, which can be either the * idle loop or adaptive-tickless usermode execution. + * + * We crowbar the ->dynticks_nmi_nesting field to DYNTICK_IRQ_NONIDLE to + * allow for the possibility of usermode upcalls messing up our count of + * interrupt nesting level during the busy period that is just now starting. */ static void rcu_eqs_exit(bool user) { struct rcu_dynticks *rdtp; - long long oldval; + long oldval; lockdep_assert_irqs_disabled(); rdtp = this_cpu_ptr(&rcu_dynticks); oldval = rdtp->dynticks_nesting; WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && oldval < 0); - if (oldval & DYNTICK_TASK_NEST_MASK) { - rdtp->dynticks_nesting += DYNTICK_TASK_NEST_VALUE; - } else { - __this_cpu_inc(disable_rcu_irq_enter); - rdtp->dynticks_nesting = DYNTICK_TASK_EXIT_IDLE; - rcu_eqs_exit_common(oldval, user); - __this_cpu_dec(disable_rcu_irq_enter); + if (oldval) { + rdtp->dynticks_nesting++; + return; } + rcu_dynticks_task_exit(); + rcu_dynticks_eqs_exit(); + rcu_cleanup_after_idle(); + trace_rcu_dyntick(TPS("End"), rdtp->dynticks_nesting, 1, rdtp->dynticks); + WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !user && !is_idle_task(current)); + WRITE_ONCE(rdtp->dynticks_nesting, 1); + WRITE_ONCE(rdtp->dynticks_nmi_nesting, DYNTICK_IRQ_NONIDLE); } /** @@ -979,11 +942,6 @@ static void rcu_eqs_exit(bool user) * Exit idle mode, in other words, -enter- the mode in which RCU * read-side critical sections can occur. * - * We crowbar the ->dynticks_nesting field to DYNTICK_TASK_NEST to - * allow for the possibility of usermode upcalls messing up our count - * of interrupt nesting level during the busy period that is just - * now starting. - * * If you add or remove a call to rcu_idle_exit(), be sure to test with * CONFIG_RCU_EQS_DEBUG=y. */ @@ -1013,65 +971,6 @@ void rcu_user_exit(void) #endif /* CONFIG_NO_HZ_FULL */ /** - * rcu_irq_enter - inform RCU that current CPU is entering irq away from idle - * - * Enter an interrupt handler, which might possibly result in exiting - * idle mode, in other words, entering the mode in which read-side critical - * sections can occur. The caller must have disabled interrupts. - * - * Note that the Linux kernel is fully capable of entering an interrupt - * handler that it never exits, for example when doing upcalls to - * user mode! This code assumes that the idle loop never does upcalls to - * user mode. If your architecture does do upcalls from the idle loop (or - * does anything else that results in unbalanced calls to the irq_enter() - * and irq_exit() functions), RCU will give you what you deserve, good - * and hard. But very infrequently and irreproducibly. - * - * Use things like work queues to work around this limitation. - * - * You have been warned. - * - * If you add or remove a call to rcu_irq_enter(), be sure to test with - * CONFIG_RCU_EQS_DEBUG=y. - */ -void rcu_irq_enter(void) -{ - struct rcu_dynticks *rdtp; - long long oldval; - - lockdep_assert_irqs_disabled(); - rdtp = this_cpu_ptr(&rcu_dynticks); - - /* Page faults can happen in NMI handlers, so check... */ - if (rdtp->dynticks_nmi_nesting) - return; - - oldval = rdtp->dynticks_nesting; - rdtp->dynticks_nesting++; - WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && - rdtp->dynticks_nesting == 0); - if (oldval) - trace_rcu_dyntick(TPS("++="), oldval, rdtp->dynticks_nesting); - else - rcu_eqs_exit_common(oldval, true); -} - -/* - * Wrapper for rcu_irq_enter() where interrupts are enabled. - * - * If you add or remove a call to rcu_irq_enter_irqson(), be sure to test - * with CONFIG_RCU_EQS_DEBUG=y. - */ -void rcu_irq_enter_irqson(void) -{ - unsigned long flags; - - local_irq_save(flags); - rcu_irq_enter(); - local_irq_restore(flags); -} - -/** * rcu_nmi_enter - inform RCU of entry to NMI context * * If the CPU was idle from RCU's viewpoint, update rdtp->dynticks and @@ -1086,7 +985,7 @@ void rcu_irq_enter_irqson(void) void rcu_nmi_enter(void) { struct rcu_dynticks *rdtp = this_cpu_ptr(&rcu_dynticks); - int incby = 2; + long incby = 2; /* Complain about underflow. */ WARN_ON_ONCE(rdtp->dynticks_nmi_nesting < 0); @@ -1103,45 +1002,61 @@ void rcu_nmi_enter(void) rcu_dynticks_eqs_exit(); incby = 1; } - rdtp->dynticks_nmi_nesting += incby; + trace_rcu_dyntick(incby == 1 ? TPS("Endirq") : TPS("++="), + rdtp->dynticks_nmi_nesting, + rdtp->dynticks_nmi_nesting + incby, rdtp->dynticks); + WRITE_ONCE(rdtp->dynticks_nmi_nesting, /* Prevent store tearing. */ + rdtp->dynticks_nmi_nesting + incby); barrier(); } /** - * rcu_nmi_exit - inform RCU of exit from NMI context + * rcu_irq_enter - inform RCU that current CPU is entering irq away from idle * - * If we are returning from the outermost NMI handler that interrupted an - * RCU-idle period, update rdtp->dynticks and rdtp->dynticks_nmi_nesting - * to let the RCU grace-period handling know that the CPU is back to - * being RCU-idle. + * Enter an interrupt handler, which might possibly result in exiting + * idle mode, in other words, entering the mode in which read-side critical + * sections can occur. The caller must have disabled interrupts. * - * If you add or remove a call to rcu_nmi_exit(), be sure to test - * with CONFIG_RCU_EQS_DEBUG=y. + * Note that the Linux kernel is fully capable of entering an interrupt + * handler that it never exits, for example when doing upcalls to user mode! + * This code assumes that the idle loop never does upcalls to user mode. + * If your architecture's idle loop does do upcalls to user mode (or does + * anything else that results in unbalanced calls to the irq_enter() and + * irq_exit() functions), RCU will give you what you deserve, good and hard. + * But very infrequently and irreproducibly. + * + * Use things like work queues to work around this limitation. + * + * You have been warned. + * + * If you add or remove a call to rcu_irq_enter(), be sure to test with + * CONFIG_RCU_EQS_DEBUG=y. */ -void rcu_nmi_exit(void) +void rcu_irq_enter(void) { struct rcu_dynticks *rdtp = this_cpu_ptr(&rcu_dynticks); - /* - * Check for ->dynticks_nmi_nesting underflow and bad ->dynticks. - * (We are exiting an NMI handler, so RCU better be paying attention - * to us!) - */ - WARN_ON_ONCE(rdtp->dynticks_nmi_nesting <= 0); - WARN_ON_ONCE(rcu_dynticks_curr_cpu_in_eqs()); + lockdep_assert_irqs_disabled(); + if (rdtp->dynticks_nmi_nesting == 0) + rcu_dynticks_task_exit(); + rcu_nmi_enter(); + if (rdtp->dynticks_nmi_nesting == 1) + rcu_cleanup_after_idle(); +} - /* - * If the nesting level is not 1, the CPU wasn't RCU-idle, so - * leave it in non-RCU-idle state. - */ - if (rdtp->dynticks_nmi_nesting != 1) { - rdtp->dynticks_nmi_nesting -= 2; - return; - } +/* + * Wrapper for rcu_irq_enter() where interrupts are enabled. + * + * If you add or remove a call to rcu_irq_enter_irqson(), be sure to test + * with CONFIG_RCU_EQS_DEBUG=y. + */ +void rcu_irq_enter_irqson(void) +{ + unsigned long flags; - /* This NMI interrupted an RCU-idle CPU, restore RCU-idleness. */ - rdtp->dynticks_nmi_nesting = 0; - rcu_dynticks_eqs_enter(); + local_irq_save(flags); + rcu_irq_enter(); + local_irq_restore(flags); } /** @@ -1233,7 +1148,8 @@ EXPORT_SYMBOL_GPL(rcu_lockdep_current_cpu_online); */ static int rcu_is_cpu_rrupt_from_idle(void) { - return __this_cpu_read(rcu_dynticks.dynticks_nesting) <= 1; + return __this_cpu_read(rcu_dynticks.dynticks_nesting) <= 0 && + __this_cpu_read(rcu_dynticks.dynticks_nmi_nesting) <= 1; } /* @@ -2789,6 +2705,11 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp) rdp->n_force_qs_snap = rsp->n_force_qs; } else if (count < rdp->qlen_last_fqs_check - qhimark) rdp->qlen_last_fqs_check = count; + + /* + * The following usually indicates a double call_rcu(). To track + * this down, try building with CONFIG_DEBUG_OBJECTS_RCU_HEAD=y. + */ WARN_ON_ONCE(rcu_segcblist_empty(&rdp->cblist) != (count == 0)); local_irq_restore(flags); @@ -3723,7 +3644,7 @@ rcu_boot_init_percpu_data(int cpu, struct rcu_state *rsp) raw_spin_lock_irqsave_rcu_node(rnp, flags); rdp->grpmask = leaf_node_cpu_bit(rdp->mynode, cpu); rdp->dynticks = &per_cpu(rcu_dynticks, cpu); - WARN_ON_ONCE(rdp->dynticks->dynticks_nesting != DYNTICK_TASK_EXIT_IDLE); + WARN_ON_ONCE(rdp->dynticks->dynticks_nesting != 1); WARN_ON_ONCE(rcu_dynticks_in_eqs(rcu_dynticks_snap(rdp->dynticks))); rdp->cpu = cpu; rdp->rsp = rsp; @@ -3752,7 +3673,7 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp) if (rcu_segcblist_empty(&rdp->cblist) && /* No early-boot CBs? */ !init_nocb_callback_list(rdp)) rcu_segcblist_init(&rdp->cblist); /* Re-enable callbacks. */ - rdp->dynticks->dynticks_nesting = DYNTICK_TASK_EXIT_IDLE; + rdp->dynticks->dynticks_nesting = 1; /* CPU not up, no tearing. */ rcu_dynticks_eqs_online(); raw_spin_unlock_rcu_node(rnp); /* irqs remain disabled. */ diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index 46a5d1991450..6488a3b0e729 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -38,9 +38,8 @@ * Dynticks per-CPU state. */ struct rcu_dynticks { - long long dynticks_nesting; /* Track irq/process nesting level. */ - /* Process level is worth LLONG_MAX/2. */ - int dynticks_nmi_nesting; /* Track NMI nesting level. */ + long dynticks_nesting; /* Track process nesting level. */ + long dynticks_nmi_nesting; /* Track irq/NMI nesting level. */ atomic_t dynticks; /* Even value for idle, else odd. */ bool rcu_need_heavy_qs; /* GP old, need heavy quiescent state. */ unsigned long rcu_qs_ctr; /* Light universal quiescent state ctr. */ diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index db85ca3975f1..fb88a028deec 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -61,7 +61,6 @@ DEFINE_PER_CPU(char, rcu_cpu_has_work); #ifdef CONFIG_RCU_NOCB_CPU static cpumask_var_t rcu_nocb_mask; /* CPUs to have callbacks offloaded. */ -static bool have_rcu_nocb_mask; /* Was rcu_nocb_mask allocated? */ static bool __read_mostly rcu_nocb_poll; /* Offload kthread are to poll. */ #endif /* #ifdef CONFIG_RCU_NOCB_CPU */ @@ -1687,7 +1686,7 @@ static void print_cpu_stall_info(struct rcu_state *rsp, int cpu) } print_cpu_stall_fast_no_hz(fast_no_hz, cpu); delta = rdp->mynode->gpnum - rdp->rcu_iw_gpnum; - pr_err("\t%d-%c%c%c%c: (%lu %s) idle=%03x/%llx/%d softirq=%u/%u fqs=%ld %s\n", + pr_err("\t%d-%c%c%c%c: (%lu %s) idle=%03x/%ld/%ld softirq=%u/%u fqs=%ld %s\n", cpu, "O."[!!cpu_online(cpu)], "o."[!!(rdp->grpmask & rdp->mynode->qsmaskinit)], @@ -1752,7 +1751,6 @@ static void increment_cpu_stall_ticks(void) static int __init rcu_nocb_setup(char *str) { alloc_bootmem_cpumask_var(&rcu_nocb_mask); - have_rcu_nocb_mask = true; cpulist_parse(str, rcu_nocb_mask); return 1; } @@ -1801,7 +1799,7 @@ static void rcu_init_one_nocb(struct rcu_node *rnp) /* Is the specified CPU a no-CBs CPU? */ bool rcu_is_nocb_cpu(int cpu) { - if (have_rcu_nocb_mask) + if (cpumask_available(rcu_nocb_mask)) return cpumask_test_cpu(cpu, rcu_nocb_mask); return false; } @@ -2295,14 +2293,13 @@ void __init rcu_init_nohz(void) need_rcu_nocb_mask = true; #endif /* #if defined(CONFIG_NO_HZ_FULL) */ - if (!have_rcu_nocb_mask && need_rcu_nocb_mask) { + if (!cpumask_available(rcu_nocb_mask) && need_rcu_nocb_mask) { if (!zalloc_cpumask_var(&rcu_nocb_mask, GFP_KERNEL)) { pr_info("rcu_nocb_mask allocation failed, callback offloading disabled.\n"); return; } - have_rcu_nocb_mask = true; } - if (!have_rcu_nocb_mask) + if (!cpumask_available(rcu_nocb_mask)) return; #if defined(CONFIG_NO_HZ_FULL) @@ -2428,7 +2425,7 @@ static void __init rcu_organize_nocb_kthreads(struct rcu_state *rsp) struct rcu_data *rdp_leader = NULL; /* Suppress misguided gcc warn. */ struct rcu_data *rdp_prev = NULL; - if (!have_rcu_nocb_mask) + if (!cpumask_available(rcu_nocb_mask)) return; if (ls == -1) { ls = int_sqrt(nr_cpu_ids); diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index fbd56d6e575b..68fa19a5e7bd 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -422,11 +422,13 @@ void init_rcu_head(struct rcu_head *head) { debug_object_init(head, &rcuhead_debug_descr); } +EXPORT_SYMBOL_GPL(init_rcu_head); void destroy_rcu_head(struct rcu_head *head) { debug_object_free(head, &rcuhead_debug_descr); } +EXPORT_SYMBOL_GPL(destroy_rcu_head); static bool rcuhead_is_static_object(void *addr) { diff --git a/kernel/relay.c b/kernel/relay.c index 39a9dfc69486..41280033a4c5 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -919,9 +919,9 @@ static int relay_file_mmap(struct file *filp, struct vm_area_struct *vma) * * Poll implemention. */ -static unsigned int relay_file_poll(struct file *filp, poll_table *wait) +static __poll_t relay_file_poll(struct file *filp, poll_table *wait) { - unsigned int mask = 0; + __poll_t mask = 0; struct rchan_buf *buf = filp->private_data; if (buf->finalized) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index a7bf32aabfda..3da7a2444a91 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -508,7 +508,8 @@ void resched_cpu(int cpu) unsigned long flags; raw_spin_lock_irqsave(&rq->lock, flags); - resched_curr(rq); + if (cpu_online(cpu) || cpu == smp_processor_id()) + resched_curr(rq); raw_spin_unlock_irqrestore(&rq->lock, flags); } @@ -2045,7 +2046,7 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags) * If the owning (remote) CPU is still in the middle of schedule() with * this task as prev, wait until its done referencing the task. * - * Pairs with the smp_store_release() in finish_lock_switch(). + * Pairs with the smp_store_release() in finish_task(). * * This ensures that tasks getting woken will be fully ordered against * their previous state and preserve Program Order. @@ -2571,6 +2572,50 @@ fire_sched_out_preempt_notifiers(struct task_struct *curr, #endif /* CONFIG_PREEMPT_NOTIFIERS */ +static inline void prepare_task(struct task_struct *next) +{ +#ifdef CONFIG_SMP + /* + * Claim the task as running, we do this before switching to it + * such that any running task will have this set. + */ + next->on_cpu = 1; +#endif +} + +static inline void finish_task(struct task_struct *prev) +{ +#ifdef CONFIG_SMP + /* + * After ->on_cpu is cleared, the task can be moved to a different CPU. + * We must ensure this doesn't happen until the switch is completely + * finished. + * + * In particular, the load of prev->state in finish_task_switch() must + * happen before this. + * + * Pairs with the smp_cond_load_acquire() in try_to_wake_up(). + */ + smp_store_release(&prev->on_cpu, 0); +#endif +} + +static inline void finish_lock_switch(struct rq *rq) +{ +#ifdef CONFIG_DEBUG_SPINLOCK + /* this is a valid case when another task releases the spinlock */ + rq->lock.owner = current; +#endif + /* + * If we are tracking spinlock dependencies then we have to + * fix up the runqueue lock - which gets 'carried over' from + * prev into current: + */ + spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_); + + raw_spin_unlock_irq(&rq->lock); +} + /** * prepare_task_switch - prepare to switch tasks * @rq: the runqueue preparing to switch @@ -2591,7 +2636,7 @@ prepare_task_switch(struct rq *rq, struct task_struct *prev, sched_info_switch(rq, prev, next); perf_event_task_sched_out(prev, next); fire_sched_out_preempt_notifiers(prev, next); - prepare_lock_switch(rq, next); + prepare_task(next); prepare_arch_switch(next); } @@ -2646,7 +2691,7 @@ static struct rq *finish_task_switch(struct task_struct *prev) * the scheduled task must drop that reference. * * We must observe prev->state before clearing prev->on_cpu (in - * finish_lock_switch), otherwise a concurrent wakeup can get prev + * finish_task), otherwise a concurrent wakeup can get prev * running on another CPU and we could rave with its RUNNING -> DEAD * transition, resulting in a double drop. */ @@ -2663,7 +2708,8 @@ static struct rq *finish_task_switch(struct task_struct *prev) * to use. */ smp_mb__after_unlock_lock(); - finish_lock_switch(rq, prev); + finish_task(prev); + finish_lock_switch(rq); finish_arch_post_lock_switch(); fire_sched_in_preempt_notifiers(current); @@ -4040,8 +4086,7 @@ recheck: return -EINVAL; } - if (attr->sched_flags & - ~(SCHED_FLAG_RESET_ON_FORK | SCHED_FLAG_RECLAIM)) + if (attr->sched_flags & ~(SCHED_FLAG_ALL | SCHED_FLAG_SUGOV)) return -EINVAL; /* @@ -4108,6 +4153,9 @@ recheck: } if (user) { + if (attr->sched_flags & SCHED_FLAG_SUGOV) + return -EINVAL; + retval = security_task_setscheduler(p); if (retval) return retval; @@ -4163,7 +4211,8 @@ change: } #endif #ifdef CONFIG_SMP - if (dl_bandwidth_enabled() && dl_policy(policy)) { + if (dl_bandwidth_enabled() && dl_policy(policy) && + !(attr->sched_flags & SCHED_FLAG_SUGOV)) { cpumask_t *span = rq->rd->span; /* @@ -4293,6 +4342,11 @@ int sched_setattr(struct task_struct *p, const struct sched_attr *attr) } EXPORT_SYMBOL_GPL(sched_setattr); +int sched_setattr_nocheck(struct task_struct *p, const struct sched_attr *attr) +{ + return __sched_setscheduler(p, attr, false, true); +} + /** * sched_setscheduler_nocheck - change the scheduling policy and/or RT priority of a thread from kernelspace. * @p: the task in question. diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index d6717a3331a1..dd062a1c8cf0 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -60,7 +60,8 @@ struct sugov_cpu { u64 last_update; /* The fields below are only needed when sharing a policy. */ - unsigned long util; + unsigned long util_cfs; + unsigned long util_dl; unsigned long max; unsigned int flags; @@ -176,21 +177,28 @@ static unsigned int get_next_freq(struct sugov_policy *sg_policy, return cpufreq_driver_resolve_freq(policy, freq); } -static void sugov_get_util(unsigned long *util, unsigned long *max, int cpu) +static void sugov_get_util(struct sugov_cpu *sg_cpu) { - struct rq *rq = cpu_rq(cpu); - unsigned long cfs_max; + struct rq *rq = cpu_rq(sg_cpu->cpu); - cfs_max = arch_scale_cpu_capacity(NULL, cpu); + sg_cpu->max = arch_scale_cpu_capacity(NULL, sg_cpu->cpu); + sg_cpu->util_cfs = cpu_util_cfs(rq); + sg_cpu->util_dl = cpu_util_dl(rq); +} - *util = min(rq->cfs.avg.util_avg, cfs_max); - *max = cfs_max; +static unsigned long sugov_aggregate_util(struct sugov_cpu *sg_cpu) +{ + /* + * Ideally we would like to set util_dl as min/guaranteed freq and + * util_cfs + util_dl as requested freq. However, cpufreq is not yet + * ready for such an interface. So, we only do the latter for now. + */ + return min(sg_cpu->util_cfs + sg_cpu->util_dl, sg_cpu->max); } -static void sugov_set_iowait_boost(struct sugov_cpu *sg_cpu, u64 time, - unsigned int flags) +static void sugov_set_iowait_boost(struct sugov_cpu *sg_cpu, u64 time) { - if (flags & SCHED_CPUFREQ_IOWAIT) { + if (sg_cpu->flags & SCHED_CPUFREQ_IOWAIT) { if (sg_cpu->iowait_boost_pending) return; @@ -264,7 +272,7 @@ static void sugov_update_single(struct update_util_data *hook, u64 time, unsigned int next_f; bool busy; - sugov_set_iowait_boost(sg_cpu, time, flags); + sugov_set_iowait_boost(sg_cpu, time); sg_cpu->last_update = time; if (!sugov_should_update_freq(sg_policy, time)) @@ -272,10 +280,12 @@ static void sugov_update_single(struct update_util_data *hook, u64 time, busy = sugov_cpu_is_busy(sg_cpu); - if (flags & SCHED_CPUFREQ_RT_DL) { + if (flags & SCHED_CPUFREQ_RT) { next_f = policy->cpuinfo.max_freq; } else { - sugov_get_util(&util, &max, sg_cpu->cpu); + sugov_get_util(sg_cpu); + max = sg_cpu->max; + util = sugov_aggregate_util(sg_cpu); sugov_iowait_boost(sg_cpu, &util, &max); next_f = get_next_freq(sg_policy, util, max); /* @@ -305,23 +315,27 @@ static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu, u64 time) s64 delta_ns; /* - * If the CPU utilization was last updated before the previous - * frequency update and the time elapsed between the last update - * of the CPU utilization and the last frequency update is long - * enough, don't take the CPU into account as it probably is - * idle now (and clear iowait_boost for it). + * If the CFS CPU utilization was last updated before the + * previous frequency update and the time elapsed between the + * last update of the CPU utilization and the last frequency + * update is long enough, reset iowait_boost and util_cfs, as + * they are now probably stale. However, still consider the + * CPU contribution if it has some DEADLINE utilization + * (util_dl). */ delta_ns = time - j_sg_cpu->last_update; if (delta_ns > TICK_NSEC) { j_sg_cpu->iowait_boost = 0; j_sg_cpu->iowait_boost_pending = false; - continue; + j_sg_cpu->util_cfs = 0; + if (j_sg_cpu->util_dl == 0) + continue; } - if (j_sg_cpu->flags & SCHED_CPUFREQ_RT_DL) + if (j_sg_cpu->flags & SCHED_CPUFREQ_RT) return policy->cpuinfo.max_freq; - j_util = j_sg_cpu->util; j_max = j_sg_cpu->max; + j_util = sugov_aggregate_util(j_sg_cpu); if (j_util * max > j_max * util) { util = j_util; max = j_max; @@ -338,22 +352,18 @@ static void sugov_update_shared(struct update_util_data *hook, u64 time, { struct sugov_cpu *sg_cpu = container_of(hook, struct sugov_cpu, update_util); struct sugov_policy *sg_policy = sg_cpu->sg_policy; - unsigned long util, max; unsigned int next_f; - sugov_get_util(&util, &max, sg_cpu->cpu); - raw_spin_lock(&sg_policy->update_lock); - sg_cpu->util = util; - sg_cpu->max = max; + sugov_get_util(sg_cpu); sg_cpu->flags = flags; - sugov_set_iowait_boost(sg_cpu, time, flags); + sugov_set_iowait_boost(sg_cpu, time); sg_cpu->last_update = time; if (sugov_should_update_freq(sg_policy, time)) { - if (flags & SCHED_CPUFREQ_RT_DL) + if (flags & SCHED_CPUFREQ_RT) next_f = sg_policy->policy->cpuinfo.max_freq; else next_f = sugov_next_freq_shared(sg_cpu, time); @@ -383,9 +393,9 @@ static void sugov_irq_work(struct irq_work *irq_work) sg_policy = container_of(irq_work, struct sugov_policy, irq_work); /* - * For RT and deadline tasks, the schedutil governor shoots the - * frequency to maximum. Special care must be taken to ensure that this - * kthread doesn't result in the same behavior. + * For RT tasks, the schedutil governor shoots the frequency to maximum. + * Special care must be taken to ensure that this kthread doesn't result + * in the same behavior. * * This is (mostly) guaranteed by the work_in_progress flag. The flag is * updated only at the end of the sugov_work() function and before that @@ -470,7 +480,20 @@ static void sugov_policy_free(struct sugov_policy *sg_policy) static int sugov_kthread_create(struct sugov_policy *sg_policy) { struct task_struct *thread; - struct sched_param param = { .sched_priority = MAX_USER_RT_PRIO / 2 }; + struct sched_attr attr = { + .size = sizeof(struct sched_attr), + .sched_policy = SCHED_DEADLINE, + .sched_flags = SCHED_FLAG_SUGOV, + .sched_nice = 0, + .sched_priority = 0, + /* + * Fake (unused) bandwidth; workaround to "fix" + * priority inheritance. + */ + .sched_runtime = 1000000, + .sched_deadline = 10000000, + .sched_period = 10000000, + }; struct cpufreq_policy *policy = sg_policy->policy; int ret; @@ -488,10 +511,10 @@ static int sugov_kthread_create(struct sugov_policy *sg_policy) return PTR_ERR(thread); } - ret = sched_setscheduler_nocheck(thread, SCHED_FIFO, ¶m); + ret = sched_setattr_nocheck(thread, &attr); if (ret) { kthread_stop(thread); - pr_warn("%s: failed to set SCHED_FIFO\n", __func__); + pr_warn("%s: failed to set SCHED_DEADLINE\n", __func__); return ret; } @@ -655,7 +678,7 @@ static int sugov_start(struct cpufreq_policy *policy) memset(sg_cpu, 0, sizeof(*sg_cpu)); sg_cpu->cpu = cpu; sg_cpu->sg_policy = sg_policy; - sg_cpu->flags = SCHED_CPUFREQ_RT; + sg_cpu->flags = 0; sg_cpu->iowait_boost_max = policy->cpuinfo.max_freq; } diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 2473736c7616..9bb0e0c412ec 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -78,7 +78,7 @@ static inline int dl_bw_cpus(int i) #endif static inline -void add_running_bw(u64 dl_bw, struct dl_rq *dl_rq) +void __add_running_bw(u64 dl_bw, struct dl_rq *dl_rq) { u64 old = dl_rq->running_bw; @@ -86,10 +86,12 @@ void add_running_bw(u64 dl_bw, struct dl_rq *dl_rq) dl_rq->running_bw += dl_bw; SCHED_WARN_ON(dl_rq->running_bw < old); /* overflow */ SCHED_WARN_ON(dl_rq->running_bw > dl_rq->this_bw); + /* kick cpufreq (see the comment in kernel/sched/sched.h). */ + cpufreq_update_util(rq_of_dl_rq(dl_rq), SCHED_CPUFREQ_DL); } static inline -void sub_running_bw(u64 dl_bw, struct dl_rq *dl_rq) +void __sub_running_bw(u64 dl_bw, struct dl_rq *dl_rq) { u64 old = dl_rq->running_bw; @@ -98,10 +100,12 @@ void sub_running_bw(u64 dl_bw, struct dl_rq *dl_rq) SCHED_WARN_ON(dl_rq->running_bw > old); /* underflow */ if (dl_rq->running_bw > old) dl_rq->running_bw = 0; + /* kick cpufreq (see the comment in kernel/sched/sched.h). */ + cpufreq_update_util(rq_of_dl_rq(dl_rq), SCHED_CPUFREQ_DL); } static inline -void add_rq_bw(u64 dl_bw, struct dl_rq *dl_rq) +void __add_rq_bw(u64 dl_bw, struct dl_rq *dl_rq) { u64 old = dl_rq->this_bw; @@ -111,7 +115,7 @@ void add_rq_bw(u64 dl_bw, struct dl_rq *dl_rq) } static inline -void sub_rq_bw(u64 dl_bw, struct dl_rq *dl_rq) +void __sub_rq_bw(u64 dl_bw, struct dl_rq *dl_rq) { u64 old = dl_rq->this_bw; @@ -123,16 +127,46 @@ void sub_rq_bw(u64 dl_bw, struct dl_rq *dl_rq) SCHED_WARN_ON(dl_rq->running_bw > dl_rq->this_bw); } +static inline +void add_rq_bw(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) +{ + if (!dl_entity_is_special(dl_se)) + __add_rq_bw(dl_se->dl_bw, dl_rq); +} + +static inline +void sub_rq_bw(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) +{ + if (!dl_entity_is_special(dl_se)) + __sub_rq_bw(dl_se->dl_bw, dl_rq); +} + +static inline +void add_running_bw(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) +{ + if (!dl_entity_is_special(dl_se)) + __add_running_bw(dl_se->dl_bw, dl_rq); +} + +static inline +void sub_running_bw(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) +{ + if (!dl_entity_is_special(dl_se)) + __sub_running_bw(dl_se->dl_bw, dl_rq); +} + void dl_change_utilization(struct task_struct *p, u64 new_bw) { struct rq *rq; + BUG_ON(p->dl.flags & SCHED_FLAG_SUGOV); + if (task_on_rq_queued(p)) return; rq = task_rq(p); if (p->dl.dl_non_contending) { - sub_running_bw(p->dl.dl_bw, &rq->dl); + sub_running_bw(&p->dl, &rq->dl); p->dl.dl_non_contending = 0; /* * If the timer handler is currently running and the @@ -144,8 +178,8 @@ void dl_change_utilization(struct task_struct *p, u64 new_bw) if (hrtimer_try_to_cancel(&p->dl.inactive_timer) == 1) put_task_struct(p); } - sub_rq_bw(p->dl.dl_bw, &rq->dl); - add_rq_bw(new_bw, &rq->dl); + __sub_rq_bw(p->dl.dl_bw, &rq->dl); + __add_rq_bw(new_bw, &rq->dl); } /* @@ -217,6 +251,9 @@ static void task_non_contending(struct task_struct *p) if (dl_se->dl_runtime == 0) return; + if (dl_entity_is_special(dl_se)) + return; + WARN_ON(hrtimer_active(&dl_se->inactive_timer)); WARN_ON(dl_se->dl_non_contending); @@ -236,12 +273,12 @@ static void task_non_contending(struct task_struct *p) */ if (zerolag_time < 0) { if (dl_task(p)) - sub_running_bw(dl_se->dl_bw, dl_rq); + sub_running_bw(dl_se, dl_rq); if (!dl_task(p) || p->state == TASK_DEAD) { struct dl_bw *dl_b = dl_bw_of(task_cpu(p)); if (p->state == TASK_DEAD) - sub_rq_bw(p->dl.dl_bw, &rq->dl); + sub_rq_bw(&p->dl, &rq->dl); raw_spin_lock(&dl_b->lock); __dl_sub(dl_b, p->dl.dl_bw, dl_bw_cpus(task_cpu(p))); __dl_clear_params(p); @@ -268,7 +305,7 @@ static void task_contending(struct sched_dl_entity *dl_se, int flags) return; if (flags & ENQUEUE_MIGRATED) - add_rq_bw(dl_se->dl_bw, dl_rq); + add_rq_bw(dl_se, dl_rq); if (dl_se->dl_non_contending) { dl_se->dl_non_contending = 0; @@ -289,7 +326,7 @@ static void task_contending(struct sched_dl_entity *dl_se, int flags) * when the "inactive timer" fired). * So, add it back. */ - add_running_bw(dl_se->dl_bw, dl_rq); + add_running_bw(dl_se, dl_rq); } } @@ -1114,7 +1151,8 @@ static void update_curr_dl(struct rq *rq) { struct task_struct *curr = rq->curr; struct sched_dl_entity *dl_se = &curr->dl; - u64 delta_exec; + u64 delta_exec, scaled_delta_exec; + int cpu = cpu_of(rq); if (!dl_task(curr) || !on_dl_rq(dl_se)) return; @@ -1134,9 +1172,6 @@ static void update_curr_dl(struct rq *rq) return; } - /* kick cpufreq (see the comment in kernel/sched/sched.h). */ - cpufreq_update_util(rq, SCHED_CPUFREQ_DL); - schedstat_set(curr->se.statistics.exec_max, max(curr->se.statistics.exec_max, delta_exec)); @@ -1148,13 +1183,39 @@ static void update_curr_dl(struct rq *rq) sched_rt_avg_update(rq, delta_exec); - if (unlikely(dl_se->flags & SCHED_FLAG_RECLAIM)) - delta_exec = grub_reclaim(delta_exec, rq, &curr->dl); - dl_se->runtime -= delta_exec; + if (dl_entity_is_special(dl_se)) + return; + + /* + * For tasks that participate in GRUB, we implement GRUB-PA: the + * spare reclaimed bandwidth is used to clock down frequency. + * + * For the others, we still need to scale reservation parameters + * according to current frequency and CPU maximum capacity. + */ + if (unlikely(dl_se->flags & SCHED_FLAG_RECLAIM)) { + scaled_delta_exec = grub_reclaim(delta_exec, + rq, + &curr->dl); + } else { + unsigned long scale_freq = arch_scale_freq_capacity(cpu); + unsigned long scale_cpu = arch_scale_cpu_capacity(NULL, cpu); + + scaled_delta_exec = cap_scale(delta_exec, scale_freq); + scaled_delta_exec = cap_scale(scaled_delta_exec, scale_cpu); + } + + dl_se->runtime -= scaled_delta_exec; throttle: if (dl_runtime_exceeded(dl_se) || dl_se->dl_yielded) { dl_se->dl_throttled = 1; + + /* If requested, inform the user about runtime overruns. */ + if (dl_runtime_exceeded(dl_se) && + (dl_se->flags & SCHED_FLAG_DL_OVERRUN)) + dl_se->dl_overrun = 1; + __dequeue_task_dl(rq, curr, 0); if (unlikely(dl_se->dl_boosted || !start_dl_timer(curr))) enqueue_task_dl(rq, curr, ENQUEUE_REPLENISH); @@ -1204,8 +1265,8 @@ static enum hrtimer_restart inactive_task_timer(struct hrtimer *timer) struct dl_bw *dl_b = dl_bw_of(task_cpu(p)); if (p->state == TASK_DEAD && dl_se->dl_non_contending) { - sub_running_bw(p->dl.dl_bw, dl_rq_of_se(&p->dl)); - sub_rq_bw(p->dl.dl_bw, dl_rq_of_se(&p->dl)); + sub_running_bw(&p->dl, dl_rq_of_se(&p->dl)); + sub_rq_bw(&p->dl, dl_rq_of_se(&p->dl)); dl_se->dl_non_contending = 0; } @@ -1222,7 +1283,7 @@ static enum hrtimer_restart inactive_task_timer(struct hrtimer *timer) sched_clock_tick(); update_rq_clock(rq); - sub_running_bw(dl_se->dl_bw, &rq->dl); + sub_running_bw(dl_se, &rq->dl); dl_se->dl_non_contending = 0; unlock: task_rq_unlock(rq, p, &rf); @@ -1416,8 +1477,8 @@ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags) dl_check_constrained_dl(&p->dl); if (p->on_rq == TASK_ON_RQ_MIGRATING || flags & ENQUEUE_RESTORE) { - add_rq_bw(p->dl.dl_bw, &rq->dl); - add_running_bw(p->dl.dl_bw, &rq->dl); + add_rq_bw(&p->dl, &rq->dl); + add_running_bw(&p->dl, &rq->dl); } /* @@ -1457,8 +1518,8 @@ static void dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags) __dequeue_task_dl(rq, p, flags); if (p->on_rq == TASK_ON_RQ_MIGRATING || flags & DEQUEUE_SAVE) { - sub_running_bw(p->dl.dl_bw, &rq->dl); - sub_rq_bw(p->dl.dl_bw, &rq->dl); + sub_running_bw(&p->dl, &rq->dl); + sub_rq_bw(&p->dl, &rq->dl); } /* @@ -1564,7 +1625,7 @@ static void migrate_task_rq_dl(struct task_struct *p) */ raw_spin_lock(&rq->lock); if (p->dl.dl_non_contending) { - sub_running_bw(p->dl.dl_bw, &rq->dl); + sub_running_bw(&p->dl, &rq->dl); p->dl.dl_non_contending = 0; /* * If the timer handler is currently running and the @@ -1576,7 +1637,7 @@ static void migrate_task_rq_dl(struct task_struct *p) if (hrtimer_try_to_cancel(&p->dl.inactive_timer) == 1) put_task_struct(p); } - sub_rq_bw(p->dl.dl_bw, &rq->dl); + sub_rq_bw(&p->dl, &rq->dl); raw_spin_unlock(&rq->lock); } @@ -2019,11 +2080,11 @@ retry: } deactivate_task(rq, next_task, 0); - sub_running_bw(next_task->dl.dl_bw, &rq->dl); - sub_rq_bw(next_task->dl.dl_bw, &rq->dl); + sub_running_bw(&next_task->dl, &rq->dl); + sub_rq_bw(&next_task->dl, &rq->dl); set_task_cpu(next_task, later_rq->cpu); - add_rq_bw(next_task->dl.dl_bw, &later_rq->dl); - add_running_bw(next_task->dl.dl_bw, &later_rq->dl); + add_rq_bw(&next_task->dl, &later_rq->dl); + add_running_bw(&next_task->dl, &later_rq->dl); activate_task(later_rq, next_task, 0); ret = 1; @@ -2111,11 +2172,11 @@ static void pull_dl_task(struct rq *this_rq) resched = true; deactivate_task(src_rq, p, 0); - sub_running_bw(p->dl.dl_bw, &src_rq->dl); - sub_rq_bw(p->dl.dl_bw, &src_rq->dl); + sub_running_bw(&p->dl, &src_rq->dl); + sub_rq_bw(&p->dl, &src_rq->dl); set_task_cpu(p, this_cpu); - add_rq_bw(p->dl.dl_bw, &this_rq->dl); - add_running_bw(p->dl.dl_bw, &this_rq->dl); + add_rq_bw(&p->dl, &this_rq->dl); + add_running_bw(&p->dl, &this_rq->dl); activate_task(this_rq, p, 0); dmin = p->dl.deadline; @@ -2224,7 +2285,7 @@ static void switched_from_dl(struct rq *rq, struct task_struct *p) task_non_contending(p); if (!task_on_rq_queued(p)) - sub_rq_bw(p->dl.dl_bw, &rq->dl); + sub_rq_bw(&p->dl, &rq->dl); /* * We cannot use inactive_task_timer() to invoke sub_running_bw() @@ -2256,7 +2317,7 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p) /* If p is not queued we will update its parameters at next wakeup. */ if (!task_on_rq_queued(p)) { - add_rq_bw(p->dl.dl_bw, &rq->dl); + add_rq_bw(&p->dl, &rq->dl); return; } @@ -2435,6 +2496,9 @@ int sched_dl_overflow(struct task_struct *p, int policy, u64 new_bw = dl_policy(policy) ? to_ratio(period, runtime) : 0; int cpus, err = -1; + if (attr->sched_flags & SCHED_FLAG_SUGOV) + return 0; + /* !deadline task may carry old deadline bandwidth */ if (new_bw == p->dl.dl_bw && task_has_dl_policy(p)) return 0; @@ -2521,6 +2585,10 @@ void __getparam_dl(struct task_struct *p, struct sched_attr *attr) */ bool __checkparam_dl(const struct sched_attr *attr) { + /* special dl tasks don't actually use any parameter */ + if (attr->sched_flags & SCHED_FLAG_SUGOV) + return true; + /* deadline != 0 */ if (attr->sched_deadline == 0) return false; @@ -2566,6 +2634,7 @@ void __dl_clear_params(struct task_struct *p) dl_se->dl_throttled = 0; dl_se->dl_yielded = 0; dl_se->dl_non_contending = 0; + dl_se->dl_overrun = 0; } bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 2fe3aa853e4d..7b6535987500 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -3020,9 +3020,7 @@ static inline void cfs_rq_util_change(struct cfs_rq *cfs_rq) /* * There are a few boundary cases this might miss but it should * get called often enough that that should (hopefully) not be - * a real problem -- added to that it only calls on the local - * CPU, so if we enqueue remotely we'll miss an update, but - * the next tick/schedule should update. + * a real problem. * * It will not get called when we go idle, because the idle * thread is a different class (!fair), nor will the utilization @@ -3091,8 +3089,6 @@ static u32 __accumulate_pelt_segments(u64 periods, u32 d1, u32 d3) return c1 + c2 + c3; } -#define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT) - /* * Accumulate the three separate parts of the sum; d1 the remainder * of the last (incomplete) period, d2 the span of full periods and d3 @@ -3122,7 +3118,7 @@ accumulate_sum(u64 delta, int cpu, struct sched_avg *sa, u32 contrib = (u32)delta; /* p == 0 -> delta < 1024 */ u64 periods; - scale_freq = arch_scale_freq_capacity(NULL, cpu); + scale_freq = arch_scale_freq_capacity(cpu); scale_cpu = arch_scale_cpu_capacity(NULL, cpu); delta += sa->period_contrib; @@ -4365,12 +4361,12 @@ static inline bool cfs_bandwidth_used(void) void cfs_bandwidth_usage_inc(void) { - static_key_slow_inc(&__cfs_bandwidth_used); + static_key_slow_inc_cpuslocked(&__cfs_bandwidth_used); } void cfs_bandwidth_usage_dec(void) { - static_key_slow_dec(&__cfs_bandwidth_used); + static_key_slow_dec_cpuslocked(&__cfs_bandwidth_used); } #else /* HAVE_JUMP_LABEL */ static bool cfs_bandwidth_used(void) @@ -5689,8 +5685,8 @@ static int wake_wide(struct task_struct *p) * soonest. For the purpose of speed we only consider the waking and previous * CPU. * - * wake_affine_idle() - only considers 'now', it check if the waking CPU is (or - * will be) idle. + * wake_affine_idle() - only considers 'now', it check if the waking CPU is + * cache-affine and is (or will be) idle. * * wake_affine_weight() - considers the weight to reflect the average * scheduling latency of the CPUs. This seems to work @@ -5701,7 +5697,13 @@ static bool wake_affine_idle(struct sched_domain *sd, struct task_struct *p, int this_cpu, int prev_cpu, int sync) { - if (idle_cpu(this_cpu)) + /* + * If this_cpu is idle, it implies the wakeup is from interrupt + * context. Only allow the move if cache is shared. Otherwise an + * interrupt intensive workload could force all tasks onto one + * node depending on the IO topology or IRQ affinity settings. + */ + if (idle_cpu(this_cpu) && cpus_share_cache(this_cpu, prev_cpu)) return true; if (sync && cpu_rq(this_cpu)->nr_running == 1) @@ -5765,12 +5767,12 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, return affine; } -static inline int task_util(struct task_struct *p); -static int cpu_util_wake(int cpu, struct task_struct *p); +static inline unsigned long task_util(struct task_struct *p); +static unsigned long cpu_util_wake(int cpu, struct task_struct *p); static unsigned long capacity_spare_wake(int cpu, struct task_struct *p) { - return capacity_orig_of(cpu) - cpu_util_wake(cpu, p); + return max_t(long, capacity_of(cpu) - cpu_util_wake(cpu, p), 0); } /* @@ -5950,7 +5952,7 @@ find_idlest_group_cpu(struct sched_group *group, struct task_struct *p, int this } } else if (shallowest_idle_cpu == -1) { load = weighted_cpuload(cpu_rq(i)); - if (load < min_load || (load == min_load && i == this_cpu)) { + if (load < min_load) { min_load = load; least_loaded_cpu = i; } @@ -6247,7 +6249,7 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) * capacity_orig) as it useful for predicting the capacity required after task * migrations (scheduler-driven DVFS). */ -static int cpu_util(int cpu) +static unsigned long cpu_util(int cpu) { unsigned long util = cpu_rq(cpu)->cfs.avg.util_avg; unsigned long capacity = capacity_orig_of(cpu); @@ -6255,7 +6257,7 @@ static int cpu_util(int cpu) return (util >= capacity) ? capacity : util; } -static inline int task_util(struct task_struct *p) +static inline unsigned long task_util(struct task_struct *p) { return p->se.avg.util_avg; } @@ -6264,7 +6266,7 @@ static inline int task_util(struct task_struct *p) * cpu_util_wake: Compute cpu utilization with any contributions from * the waking task p removed. */ -static int cpu_util_wake(int cpu, struct task_struct *p) +static unsigned long cpu_util_wake(int cpu, struct task_struct *p) { unsigned long util, capacity; @@ -6449,8 +6451,7 @@ static void task_dead_fair(struct task_struct *p) } #endif /* CONFIG_SMP */ -static unsigned long -wakeup_gran(struct sched_entity *curr, struct sched_entity *se) +static unsigned long wakeup_gran(struct sched_entity *se) { unsigned long gran = sysctl_sched_wakeup_granularity; @@ -6492,7 +6493,7 @@ wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se) if (vdiff <= 0) return -1; - gran = wakeup_gran(curr, se); + gran = wakeup_gran(se); if (vdiff > gran) return 1; diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 665ace2fc558..862a513adca3 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2212,7 +2212,7 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p) if (p->nr_cpus_allowed > 1 && rq->rt.overloaded) queue_push_tasks(rq); #endif /* CONFIG_SMP */ - if (p->prio < rq->curr->prio) + if (p->prio < rq->curr->prio && cpu_online(cpu_of(rq))) resched_curr(rq); } } diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index b19552a212de..2e95505e23c6 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -156,13 +156,39 @@ static inline int task_has_dl_policy(struct task_struct *p) return dl_policy(p->policy); } +#define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT) + +/* + * !! For sched_setattr_nocheck() (kernel) only !! + * + * This is actually gross. :( + * + * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE + * tasks, but still be able to sleep. We need this on platforms that cannot + * atomically change clock frequency. Remove once fast switching will be + * available on such platforms. + * + * SUGOV stands for SchedUtil GOVernor. + */ +#define SCHED_FLAG_SUGOV 0x10000000 + +static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se) +{ +#ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL + return unlikely(dl_se->flags & SCHED_FLAG_SUGOV); +#else + return false; +#endif +} + /* * Tells if entity @a should preempt entity @b. */ static inline bool dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b) { - return dl_time_before(a->deadline, b->deadline); + return dl_entity_is_special(a) || + dl_time_before(a->deadline, b->deadline); } /* @@ -1328,47 +1354,6 @@ static inline int task_on_rq_migrating(struct task_struct *p) # define finish_arch_post_lock_switch() do { } while (0) #endif -static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) -{ -#ifdef CONFIG_SMP - /* - * We can optimise this out completely for !SMP, because the - * SMP rebalancing from interrupt is the only thing that cares - * here. - */ - next->on_cpu = 1; -#endif -} - -static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) -{ -#ifdef CONFIG_SMP - /* - * After ->on_cpu is cleared, the task can be moved to a different CPU. - * We must ensure this doesn't happen until the switch is completely - * finished. - * - * In particular, the load of prev->state in finish_task_switch() must - * happen before this. - * - * Pairs with the smp_cond_load_acquire() in try_to_wake_up(). - */ - smp_store_release(&prev->on_cpu, 0); -#endif -#ifdef CONFIG_DEBUG_SPINLOCK - /* this is a valid case when another task releases the spinlock */ - rq->lock.owner = current; -#endif - /* - * If we are tracking spinlock dependencies then we have to - * fix up the runqueue lock - which gets 'carried over' from - * prev into current: - */ - spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_); - - raw_spin_unlock_irq(&rq->lock); -} - /* * wake flags */ @@ -1687,17 +1672,17 @@ static inline int hrtick_enabled(struct rq *rq) #endif /* CONFIG_SCHED_HRTICK */ -#ifdef CONFIG_SMP -extern void sched_avg_update(struct rq *rq); - #ifndef arch_scale_freq_capacity static __always_inline -unsigned long arch_scale_freq_capacity(struct sched_domain *sd, int cpu) +unsigned long arch_scale_freq_capacity(int cpu) { return SCHED_CAPACITY_SCALE; } #endif +#ifdef CONFIG_SMP +extern void sched_avg_update(struct rq *rq); + #ifndef arch_scale_cpu_capacity static __always_inline unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu) @@ -1711,10 +1696,17 @@ unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu) static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { - rq->rt_avg += rt_delta * arch_scale_freq_capacity(NULL, cpu_of(rq)); + rq->rt_avg += rt_delta * arch_scale_freq_capacity(cpu_of(rq)); sched_avg_update(rq); } #else +#ifndef arch_scale_cpu_capacity +static __always_inline +unsigned long arch_scale_cpu_capacity(void __always_unused *sd, int cpu) +{ + return SCHED_CAPACITY_SCALE; +} +#endif static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { } static inline void sched_avg_update(struct rq *rq) { } #endif @@ -2096,14 +2088,14 @@ DECLARE_PER_CPU(struct update_util_data *, cpufreq_update_util_data); * The way cpufreq is currently arranged requires it to evaluate the CPU * performance state (frequency/voltage) on a regular basis to prevent it from * being stuck in a completely inadequate performance level for too long. - * That is not guaranteed to happen if the updates are only triggered from CFS, - * though, because they may not be coming in if RT or deadline tasks are active - * all the time (or there are RT and DL tasks only). + * That is not guaranteed to happen if the updates are only triggered from CFS + * and DL, though, because they may not be coming in if only RT tasks are + * active all the time (or there are RT tasks only). * - * As a workaround for that issue, this function is called by the RT and DL - * sched classes to trigger extra cpufreq updates to prevent it from stalling, + * As a workaround for that issue, this function is called periodically by the + * RT sched class to trigger extra cpufreq updates to prevent it from stalling, * but that really is a band-aid. Going forward it should be replaced with - * solutions targeted more specifically at RT and DL tasks. + * solutions targeted more specifically at RT tasks. */ static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) { @@ -2125,3 +2117,17 @@ static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {} #else /* arch_scale_freq_capacity */ #define arch_scale_freq_invariant() (false) #endif + +#ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL + +static inline unsigned long cpu_util_dl(struct rq *rq) +{ + return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT; +} + +static inline unsigned long cpu_util_cfs(struct rq *rq) +{ + return rq->cfs.avg.util_avg; +} + +#endif diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 5f0dfb2abb8d..940fa408a288 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -515,7 +515,7 @@ void put_seccomp_filter(struct task_struct *tsk) static void seccomp_init_siginfo(siginfo_t *info, int syscall, int reason) { - memset(info, 0, sizeof(*info)); + clear_siginfo(info); info->si_signo = SIGSYS; info->si_code = SYS_SECCOMP; info->si_call_addr = (void __user *)KSTK_EIP(current); @@ -978,49 +978,68 @@ long prctl_set_seccomp(unsigned long seccomp_mode, char __user *filter) } #if defined(CONFIG_SECCOMP_FILTER) && defined(CONFIG_CHECKPOINT_RESTORE) -long seccomp_get_filter(struct task_struct *task, unsigned long filter_off, - void __user *data) +static struct seccomp_filter *get_nth_filter(struct task_struct *task, + unsigned long filter_off) { - struct seccomp_filter *filter; - struct sock_fprog_kern *fprog; - long ret; - unsigned long count = 0; - - if (!capable(CAP_SYS_ADMIN) || - current->seccomp.mode != SECCOMP_MODE_DISABLED) { - return -EACCES; - } + struct seccomp_filter *orig, *filter; + unsigned long count; + /* + * Note: this is only correct because the caller should be the (ptrace) + * tracer of the task, otherwise lock_task_sighand is needed. + */ spin_lock_irq(&task->sighand->siglock); + if (task->seccomp.mode != SECCOMP_MODE_FILTER) { - ret = -EINVAL; - goto out; + spin_unlock_irq(&task->sighand->siglock); + return ERR_PTR(-EINVAL); } - filter = task->seccomp.filter; - while (filter) { - filter = filter->prev; + orig = task->seccomp.filter; + __get_seccomp_filter(orig); + spin_unlock_irq(&task->sighand->siglock); + + count = 0; + for (filter = orig; filter; filter = filter->prev) count++; - } if (filter_off >= count) { - ret = -ENOENT; + filter = ERR_PTR(-ENOENT); goto out; } - count -= filter_off; - filter = task->seccomp.filter; - while (filter && count > 1) { - filter = filter->prev; + count -= filter_off; + for (filter = orig; filter && count > 1; filter = filter->prev) count--; - } if (WARN_ON(count != 1 || !filter)) { - /* The filter tree shouldn't shrink while we're using it. */ - ret = -ENOENT; + filter = ERR_PTR(-ENOENT); goto out; } + __get_seccomp_filter(filter); + +out: + __put_seccomp_filter(orig); + return filter; +} + +long seccomp_get_filter(struct task_struct *task, unsigned long filter_off, + void __user *data) +{ + struct seccomp_filter *filter; + struct sock_fprog_kern *fprog; + long ret; + + if (!capable(CAP_SYS_ADMIN) || + current->seccomp.mode != SECCOMP_MODE_DISABLED) { + return -EACCES; + } + + filter = get_nth_filter(task, filter_off); + if (IS_ERR(filter)) + return PTR_ERR(filter); + fprog = filter->prog->orig_prog; if (!fprog) { /* This must be a new non-cBPF filter, since we save @@ -1035,17 +1054,44 @@ long seccomp_get_filter(struct task_struct *task, unsigned long filter_off, if (!data) goto out; - __get_seccomp_filter(filter); - spin_unlock_irq(&task->sighand->siglock); - if (copy_to_user(data, fprog->filter, bpf_classic_proglen(fprog))) ret = -EFAULT; +out: __put_seccomp_filter(filter); return ret; +} -out: - spin_unlock_irq(&task->sighand->siglock); +long seccomp_get_metadata(struct task_struct *task, + unsigned long size, void __user *data) +{ + long ret; + struct seccomp_filter *filter; + struct seccomp_metadata kmd = {}; + + if (!capable(CAP_SYS_ADMIN) || + current->seccomp.mode != SECCOMP_MODE_DISABLED) { + return -EACCES; + } + + size = min_t(unsigned long, size, sizeof(kmd)); + + if (copy_from_user(&kmd, data, size)) + return -EFAULT; + + filter = get_nth_filter(task, kmd.filter_off); + if (IS_ERR(filter)) + return PTR_ERR(filter); + + memset(&kmd, 0, sizeof(kmd)); + if (filter->log) + kmd.flags |= SECCOMP_FILTER_FLAG_LOG; + + ret = size; + if (copy_to_user(data, &kmd, size)) + ret = -EFAULT; + + __put_seccomp_filter(filter); return ret; } #endif diff --git a/kernel/signal.c b/kernel/signal.c index 9558664bd9ec..c6e4c83dc090 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -40,6 +40,7 @@ #include <linux/cn_proc.h> #include <linux/compiler.h> #include <linux/posix-timers.h> +#include <linux/livepatch.h> #define CREATE_TRACE_POINTS #include <trace/events/signal.h> @@ -165,7 +166,8 @@ void recalc_sigpending_and_wake(struct task_struct *t) void recalc_sigpending(void) { - if (!recalc_sigpending_tsk(current) && !freezing(current)) + if (!recalc_sigpending_tsk(current) && !freezing(current) && + !klp_patch_pending(current)) clear_thread_flag(TIF_SIGPENDING); } @@ -549,6 +551,7 @@ still_pending: * a fast-pathed signal or we must have been * out of queue space. So zero out the info. */ + clear_siginfo(info); info->si_signo = sig; info->si_errno = 0; info->si_code = SI_USER; @@ -642,6 +645,9 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) spin_unlock(&tsk->sighand->siglock); posixtimer_rearm(info); spin_lock(&tsk->sighand->siglock); + + /* Don't expose the si_sys_private value to userspace */ + info->si_sys_private = 0; } #endif return signr; @@ -1043,6 +1049,7 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t, list_add_tail(&q->list, &pending->list); switch ((unsigned long) info) { case (unsigned long) SEND_SIG_NOINFO: + clear_siginfo(&q->info); q->info.si_signo = sig; q->info.si_errno = 0; q->info.si_code = SI_USER; @@ -1051,6 +1058,7 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t, q->info.si_uid = from_kuid_munged(current_user_ns(), current_uid()); break; case (unsigned long) SEND_SIG_PRIV: + clear_siginfo(&q->info); q->info.si_signo = sig; q->info.si_errno = 0; q->info.si_code = SI_KERNEL; @@ -1485,6 +1493,129 @@ force_sigsegv(int sig, struct task_struct *p) return 0; } +int force_sig_fault(int sig, int code, void __user *addr + ___ARCH_SI_TRAPNO(int trapno) + ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr) + , struct task_struct *t) +{ + struct siginfo info; + + clear_siginfo(&info); + info.si_signo = sig; + info.si_errno = 0; + info.si_code = code; + info.si_addr = addr; +#ifdef __ARCH_SI_TRAPNO + info.si_trapno = trapno; +#endif +#ifdef __ia64__ + info.si_imm = imm; + info.si_flags = flags; + info.si_isr = isr; +#endif + return force_sig_info(info.si_signo, &info, t); +} + +int send_sig_fault(int sig, int code, void __user *addr + ___ARCH_SI_TRAPNO(int trapno) + ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr) + , struct task_struct *t) +{ + struct siginfo info; + + clear_siginfo(&info); + info.si_signo = sig; + info.si_errno = 0; + info.si_code = code; + info.si_addr = addr; +#ifdef __ARCH_SI_TRAPNO + info.si_trapno = trapno; +#endif +#ifdef __ia64__ + info.si_imm = imm; + info.si_flags = flags; + info.si_isr = isr; +#endif + return send_sig_info(info.si_signo, &info, t); +} + +#if defined(BUS_MCEERR_AO) && defined(BUS_MCEERR_AR) +int force_sig_mceerr(int code, void __user *addr, short lsb, struct task_struct *t) +{ + struct siginfo info; + + WARN_ON((code != BUS_MCEERR_AO) && (code != BUS_MCEERR_AR)); + clear_siginfo(&info); + info.si_signo = SIGBUS; + info.si_errno = 0; + info.si_code = code; + info.si_addr = addr; + info.si_addr_lsb = lsb; + return force_sig_info(info.si_signo, &info, t); +} + +int send_sig_mceerr(int code, void __user *addr, short lsb, struct task_struct *t) +{ + struct siginfo info; + + WARN_ON((code != BUS_MCEERR_AO) && (code != BUS_MCEERR_AR)); + clear_siginfo(&info); + info.si_signo = SIGBUS; + info.si_errno = 0; + info.si_code = code; + info.si_addr = addr; + info.si_addr_lsb = lsb; + return send_sig_info(info.si_signo, &info, t); +} +EXPORT_SYMBOL(send_sig_mceerr); +#endif + +#ifdef SEGV_BNDERR +int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper) +{ + struct siginfo info; + + clear_siginfo(&info); + info.si_signo = SIGSEGV; + info.si_errno = 0; + info.si_code = SEGV_BNDERR; + info.si_addr = addr; + info.si_lower = lower; + info.si_upper = upper; + return force_sig_info(info.si_signo, &info, current); +} +#endif + +#ifdef SEGV_PKUERR +int force_sig_pkuerr(void __user *addr, u32 pkey) +{ + struct siginfo info; + + clear_siginfo(&info); + info.si_signo = SIGSEGV; + info.si_errno = 0; + info.si_code = SEGV_PKUERR; + info.si_addr = addr; + info.si_pkey = pkey; + return force_sig_info(info.si_signo, &info, current); +} +#endif + +/* For the crazy architectures that include trap information in + * the errno field, instead of an actual errno value. + */ +int force_sig_ptrace_errno_trap(int errno, void __user *addr) +{ + struct siginfo info; + + clear_siginfo(&info); + info.si_signo = SIGTRAP; + info.si_errno = errno; + info.si_code = TRAP_HWBKPT; + info.si_addr = addr; + return force_sig_info(info.si_signo, &info, current); +} + int kill_pgrp(struct pid *pid, int sig, int priv) { int ret; @@ -1623,6 +1754,7 @@ bool do_notify_parent(struct task_struct *tsk, int sig) sig = SIGCHLD; } + clear_siginfo(&info); info.si_signo = sig; info.si_errno = 0; /* @@ -1717,6 +1849,7 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, parent = tsk->real_parent; } + clear_siginfo(&info); info.si_signo = SIGCHLD; info.si_errno = 0; /* @@ -1929,7 +2062,7 @@ static void ptrace_do_notify(int signr, int exit_code, int why) { siginfo_t info; - memset(&info, 0, sizeof info); + clear_siginfo(&info); info.si_signo = signr; info.si_code = exit_code; info.si_pid = task_pid_vnr(current); @@ -2136,6 +2269,7 @@ static int ptrace_signal(int signr, siginfo_t *info) * have updated *info via PTRACE_SETSIGINFO. */ if (signr != info->si_signo) { + clear_siginfo(info); info->si_signo = signr; info->si_errno = 0; info->si_code = SI_USER; @@ -2688,9 +2822,7 @@ enum siginfo_layout siginfo_layout(int sig, int si_code) #endif [SIGCHLD] = { NSIGCHLD, SIL_CHLD }, [SIGPOLL] = { NSIGPOLL, SIL_POLL }, -#ifdef __ARCH_SIGSYS [SIGSYS] = { NSIGSYS, SIL_SYS }, -#endif }; if ((sig < ARRAY_SIZE(filter)) && (si_code <= filter[sig].limit)) layout = filter[sig].layout; @@ -2712,12 +2844,14 @@ enum siginfo_layout siginfo_layout(int sig, int si_code) if ((sig == SIGFPE) && (si_code == FPE_FIXME)) layout = SIL_FAULT; #endif +#ifdef BUS_FIXME + if ((sig == SIGBUS) && (si_code == BUS_FIXME)) + layout = SIL_FAULT; +#endif } return layout; } -#ifndef HAVE_ARCH_COPY_SIGINFO_TO_USER - int copy_siginfo_to_user(siginfo_t __user *to, const siginfo_t *from) { int err; @@ -2756,13 +2890,21 @@ int copy_siginfo_to_user(siginfo_t __user *to, const siginfo_t *from) #ifdef __ARCH_SI_TRAPNO err |= __put_user(from->si_trapno, &to->si_trapno); #endif -#ifdef BUS_MCEERR_AO +#ifdef __ia64__ + err |= __put_user(from->si_imm, &to->si_imm); + err |= __put_user(from->si_flags, &to->si_flags); + err |= __put_user(from->si_isr, &to->si_isr); +#endif /* * Other callers might not initialize the si_lsb field, * so check explicitly for the right codes here. */ - if (from->si_signo == SIGBUS && - (from->si_code == BUS_MCEERR_AR || from->si_code == BUS_MCEERR_AO)) +#ifdef BUS_MCEERR_AR + if (from->si_signo == SIGBUS && from->si_code == BUS_MCEERR_AR) + err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb); +#endif +#ifdef BUS_MCEERR_AO + if (from->si_signo == SIGBUS && from->si_code == BUS_MCEERR_AO) err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb); #endif #ifdef SEGV_BNDERR @@ -2788,18 +2930,185 @@ int copy_siginfo_to_user(siginfo_t __user *to, const siginfo_t *from) err |= __put_user(from->si_uid, &to->si_uid); err |= __put_user(from->si_ptr, &to->si_ptr); break; -#ifdef __ARCH_SIGSYS case SIL_SYS: err |= __put_user(from->si_call_addr, &to->si_call_addr); err |= __put_user(from->si_syscall, &to->si_syscall); err |= __put_user(from->si_arch, &to->si_arch); break; -#endif } return err; } +#ifdef CONFIG_COMPAT +int copy_siginfo_to_user32(struct compat_siginfo __user *to, + const struct siginfo *from) +#if defined(CONFIG_X86_X32_ABI) || defined(CONFIG_IA32_EMULATION) +{ + return __copy_siginfo_to_user32(to, from, in_x32_syscall()); +} +int __copy_siginfo_to_user32(struct compat_siginfo __user *to, + const struct siginfo *from, bool x32_ABI) +#endif +{ + struct compat_siginfo new; + memset(&new, 0, sizeof(new)); + + new.si_signo = from->si_signo; + new.si_errno = from->si_errno; + new.si_code = from->si_code; + switch(siginfo_layout(from->si_signo, from->si_code)) { + case SIL_KILL: + new.si_pid = from->si_pid; + new.si_uid = from->si_uid; + break; + case SIL_TIMER: + new.si_tid = from->si_tid; + new.si_overrun = from->si_overrun; + new.si_int = from->si_int; + break; + case SIL_POLL: + new.si_band = from->si_band; + new.si_fd = from->si_fd; + break; + case SIL_FAULT: + new.si_addr = ptr_to_compat(from->si_addr); +#ifdef __ARCH_SI_TRAPNO + new.si_trapno = from->si_trapno; +#endif +#ifdef BUS_MCEERR_AR + if ((from->si_signo == SIGBUS) && (from->si_code == BUS_MCEERR_AR)) + new.si_addr_lsb = from->si_addr_lsb; +#endif +#ifdef BUS_MCEERR_AO + if ((from->si_signo == SIGBUS) && (from->si_code == BUS_MCEERR_AO)) + new.si_addr_lsb = from->si_addr_lsb; +#endif +#ifdef SEGV_BNDERR + if ((from->si_signo == SIGSEGV) && + (from->si_code == SEGV_BNDERR)) { + new.si_lower = ptr_to_compat(from->si_lower); + new.si_upper = ptr_to_compat(from->si_upper); + } +#endif +#ifdef SEGV_PKUERR + if ((from->si_signo == SIGSEGV) && + (from->si_code == SEGV_PKUERR)) + new.si_pkey = from->si_pkey; +#endif + + break; + case SIL_CHLD: + new.si_pid = from->si_pid; + new.si_uid = from->si_uid; + new.si_status = from->si_status; +#ifdef CONFIG_X86_X32_ABI + if (x32_ABI) { + new._sifields._sigchld_x32._utime = from->si_utime; + new._sifields._sigchld_x32._stime = from->si_stime; + } else +#endif + { + new.si_utime = from->si_utime; + new.si_stime = from->si_stime; + } + break; + case SIL_RT: + new.si_pid = from->si_pid; + new.si_uid = from->si_uid; + new.si_int = from->si_int; + break; + case SIL_SYS: + new.si_call_addr = ptr_to_compat(from->si_call_addr); + new.si_syscall = from->si_syscall; + new.si_arch = from->si_arch; + break; + } + + if (copy_to_user(to, &new, sizeof(struct compat_siginfo))) + return -EFAULT; + + return 0; +} + +int copy_siginfo_from_user32(struct siginfo *to, + const struct compat_siginfo __user *ufrom) +{ + struct compat_siginfo from; + + if (copy_from_user(&from, ufrom, sizeof(struct compat_siginfo))) + return -EFAULT; + + clear_siginfo(to); + to->si_signo = from.si_signo; + to->si_errno = from.si_errno; + to->si_code = from.si_code; + switch(siginfo_layout(from.si_signo, from.si_code)) { + case SIL_KILL: + to->si_pid = from.si_pid; + to->si_uid = from.si_uid; + break; + case SIL_TIMER: + to->si_tid = from.si_tid; + to->si_overrun = from.si_overrun; + to->si_int = from.si_int; + break; + case SIL_POLL: + to->si_band = from.si_band; + to->si_fd = from.si_fd; + break; + case SIL_FAULT: + to->si_addr = compat_ptr(from.si_addr); +#ifdef __ARCH_SI_TRAPNO + to->si_trapno = from.si_trapno; +#endif +#ifdef BUS_MCEERR_AR + if ((from.si_signo == SIGBUS) && (from.si_code == BUS_MCEERR_AR)) + to->si_addr_lsb = from.si_addr_lsb; +#endif +#ifdef BUS_MCEER_AO + if ((from.si_signo == SIGBUS) && (from.si_code == BUS_MCEERR_AO)) + to->si_addr_lsb = from.si_addr_lsb; +#endif +#ifdef SEGV_BNDERR + if ((from.si_signo == SIGSEGV) && (from.si_code == SEGV_BNDERR)) { + to->si_lower = compat_ptr(from.si_lower); + to->si_upper = compat_ptr(from.si_upper); + } +#endif +#ifdef SEGV_PKUERR + if ((from.si_signo == SIGSEGV) && (from.si_code == SEGV_PKUERR)) + to->si_pkey = from.si_pkey; +#endif + break; + case SIL_CHLD: + to->si_pid = from.si_pid; + to->si_uid = from.si_uid; + to->si_status = from.si_status; +#ifdef CONFIG_X86_X32_ABI + if (in_x32_syscall()) { + to->si_utime = from._sifields._sigchld_x32._utime; + to->si_stime = from._sifields._sigchld_x32._stime; + } else #endif + { + to->si_utime = from.si_utime; + to->si_stime = from.si_stime; + } + break; + case SIL_RT: + to->si_pid = from.si_pid; + to->si_uid = from.si_uid; + to->si_int = from.si_int; + break; + case SIL_SYS: + to->si_call_addr = compat_ptr(from.si_call_addr); + to->si_syscall = from.si_syscall; + to->si_arch = from.si_arch; + break; + } + return 0; +} +#endif /* CONFIG_COMPAT */ /** * do_sigtimedwait - wait for queued signals specified in @which @@ -2937,6 +3246,7 @@ SYSCALL_DEFINE2(kill, pid_t, pid, int, sig) { struct siginfo info; + clear_siginfo(&info); info.si_signo = sig; info.si_errno = 0; info.si_code = SI_USER; @@ -2978,8 +3288,9 @@ do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info) static int do_tkill(pid_t tgid, pid_t pid, int sig) { - struct siginfo info = {}; + struct siginfo info; + clear_siginfo(&info); info.si_signo = sig; info.si_errno = 0; info.si_code = SI_TKILL; @@ -3060,7 +3371,7 @@ COMPAT_SYSCALL_DEFINE3(rt_sigqueueinfo, int, sig, struct compat_siginfo __user *, uinfo) { - siginfo_t info = {}; + siginfo_t info; int ret = copy_siginfo_from_user32(&info, uinfo); if (unlikely(ret)) return ret; @@ -3104,7 +3415,7 @@ COMPAT_SYSCALL_DEFINE4(rt_tgsigqueueinfo, int, sig, struct compat_siginfo __user *, uinfo) { - siginfo_t info = {}; + siginfo_t info; if (copy_siginfo_from_user32(&info, uinfo)) return -EFAULT; @@ -3677,6 +3988,7 @@ void __init signals_init(void) /* If this check fails, the __ARCH_SI_PREAMBLE_SIZE value is wrong! */ BUILD_BUG_ON(__ARCH_SI_PREAMBLE_SIZE != offsetof(struct siginfo, _sifields._pad)); + BUILD_BUG_ON(sizeof(struct siginfo) != SI_MAX_SIZE); sigqueue_cachep = KMEM_CACHE(sigqueue, SLAB_PANIC); } @@ -3684,26 +3996,25 @@ void __init signals_init(void) #ifdef CONFIG_KGDB_KDB #include <linux/kdb.h> /* - * kdb_send_sig_info - Allows kdb to send signals without exposing + * kdb_send_sig - Allows kdb to send signals without exposing * signal internals. This function checks if the required locks are * available before calling the main signal code, to avoid kdb * deadlocks. */ -void -kdb_send_sig_info(struct task_struct *t, struct siginfo *info) +void kdb_send_sig(struct task_struct *t, int sig) { static struct task_struct *kdb_prev_t; - int sig, new_t; + int new_t, ret; if (!spin_trylock(&t->sighand->siglock)) { kdb_printf("Can't do kill command now.\n" "The sigmask lock is held somewhere else in " "kernel, try again later\n"); return; } - spin_unlock(&t->sighand->siglock); new_t = kdb_prev_t != t; kdb_prev_t = t; if (t->state != TASK_RUNNING && new_t) { + spin_unlock(&t->sighand->siglock); kdb_printf("Process is not RUNNING, sending a signal from " "kdb risks deadlock\n" "on the run queue locks. " @@ -3712,8 +4023,9 @@ kdb_send_sig_info(struct task_struct *t, struct siginfo *info) "the deadlock.\n"); return; } - sig = info->si_signo; - if (send_sig_info(sig, info, t)) + ret = send_signal(sig, SEND_SIG_PRIV, t, false); + spin_unlock(&t->sighand->siglock); + if (ret) kdb_printf("Fail to deliver Signal %d to process %d.\n", sig, t->pid); else diff --git a/kernel/softirq.c b/kernel/softirq.c index 2f5e87f1bae2..24d243ef8e71 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -665,7 +665,7 @@ static void run_ksoftirqd(unsigned int cpu) */ __do_softirq(); local_irq_enable(); - cond_resched_rcu_qs(); + cond_resched(); return; } local_irq_enable(); diff --git a/kernel/sys.c b/kernel/sys.c index 83ffd7dccf23..f2289de20e19 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -135,7 +135,7 @@ EXPORT_SYMBOL(overflowgid); */ int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; -int fs_overflowgid = DEFAULT_FS_OVERFLOWUID; +int fs_overflowgid = DEFAULT_FS_OVERFLOWGID; EXPORT_SYMBOL(fs_overflowuid); EXPORT_SYMBOL(fs_overflowgid); diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index d32520840fde..ae0c8a411fe7 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -60,6 +60,15 @@ #include "tick-internal.h" /* + * Masks for selecting the soft and hard context timers from + * cpu_base->active + */ +#define MASK_SHIFT (HRTIMER_BASE_MONOTONIC_SOFT) +#define HRTIMER_ACTIVE_HARD ((1U << MASK_SHIFT) - 1) +#define HRTIMER_ACTIVE_SOFT (HRTIMER_ACTIVE_HARD << MASK_SHIFT) +#define HRTIMER_ACTIVE_ALL (HRTIMER_ACTIVE_SOFT | HRTIMER_ACTIVE_HARD) + +/* * The timer bases: * * There are more clockids than hrtimer bases. Thus, we index @@ -70,7 +79,6 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) = { .lock = __RAW_SPIN_LOCK_UNLOCKED(hrtimer_bases.lock), - .seq = SEQCNT_ZERO(hrtimer_bases.seq), .clock_base = { { @@ -93,6 +101,26 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) = .clockid = CLOCK_TAI, .get_time = &ktime_get_clocktai, }, + { + .index = HRTIMER_BASE_MONOTONIC_SOFT, + .clockid = CLOCK_MONOTONIC, + .get_time = &ktime_get, + }, + { + .index = HRTIMER_BASE_REALTIME_SOFT, + .clockid = CLOCK_REALTIME, + .get_time = &ktime_get_real, + }, + { + .index = HRTIMER_BASE_BOOTTIME_SOFT, + .clockid = CLOCK_BOOTTIME, + .get_time = &ktime_get_boottime, + }, + { + .index = HRTIMER_BASE_TAI_SOFT, + .clockid = CLOCK_TAI, + .get_time = &ktime_get_clocktai, + }, } }; @@ -118,7 +146,6 @@ static const int hrtimer_clock_to_base_table[MAX_CLOCKS] = { * timer->base->cpu_base */ static struct hrtimer_cpu_base migration_cpu_base = { - .seq = SEQCNT_ZERO(migration_cpu_base), .clock_base = { { .cpu_base = &migration_cpu_base, }, }, }; @@ -156,45 +183,33 @@ struct hrtimer_clock_base *lock_hrtimer_base(const struct hrtimer *timer, } /* - * With HIGHRES=y we do not migrate the timer when it is expiring - * before the next event on the target cpu because we cannot reprogram - * the target cpu hardware and we would cause it to fire late. + * We do not migrate the timer when it is expiring before the next + * event on the target cpu. When high resolution is enabled, we cannot + * reprogram the target cpu hardware and we would cause it to fire + * late. To keep it simple, we handle the high resolution enabled and + * disabled case similar. * * Called with cpu_base->lock of target cpu held. */ static int hrtimer_check_target(struct hrtimer *timer, struct hrtimer_clock_base *new_base) { -#ifdef CONFIG_HIGH_RES_TIMERS ktime_t expires; - if (!new_base->cpu_base->hres_active) - return 0; - expires = ktime_sub(hrtimer_get_expires(timer), new_base->offset); - return expires <= new_base->cpu_base->expires_next; -#else - return 0; -#endif + return expires < new_base->cpu_base->expires_next; } -#ifdef CONFIG_NO_HZ_COMMON -static inline -struct hrtimer_cpu_base *get_target_base(struct hrtimer_cpu_base *base, - int pinned) -{ - if (pinned || !base->migration_enabled) - return base; - return &per_cpu(hrtimer_bases, get_nohz_timer_target()); -} -#else static inline struct hrtimer_cpu_base *get_target_base(struct hrtimer_cpu_base *base, int pinned) { +#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) + if (static_branch_likely(&timers_migration_enabled) && !pinned) + return &per_cpu(hrtimer_bases, get_nohz_timer_target()); +#endif return base; } -#endif /* * We switch the timer base to a power-optimized selected CPU target, @@ -396,7 +411,8 @@ static inline void debug_hrtimer_init(struct hrtimer *timer) debug_object_init(timer, &hrtimer_debug_descr); } -static inline void debug_hrtimer_activate(struct hrtimer *timer) +static inline void debug_hrtimer_activate(struct hrtimer *timer, + enum hrtimer_mode mode) { debug_object_activate(timer, &hrtimer_debug_descr); } @@ -429,8 +445,10 @@ void destroy_hrtimer_on_stack(struct hrtimer *timer) EXPORT_SYMBOL_GPL(destroy_hrtimer_on_stack); #else + static inline void debug_hrtimer_init(struct hrtimer *timer) { } -static inline void debug_hrtimer_activate(struct hrtimer *timer) { } +static inline void debug_hrtimer_activate(struct hrtimer *timer, + enum hrtimer_mode mode) { } static inline void debug_hrtimer_deactivate(struct hrtimer *timer) { } #endif @@ -442,10 +460,11 @@ debug_init(struct hrtimer *timer, clockid_t clockid, trace_hrtimer_init(timer, clockid, mode); } -static inline void debug_activate(struct hrtimer *timer) +static inline void debug_activate(struct hrtimer *timer, + enum hrtimer_mode mode) { - debug_hrtimer_activate(timer); - trace_hrtimer_start(timer); + debug_hrtimer_activate(timer, mode); + trace_hrtimer_start(timer, mode); } static inline void debug_deactivate(struct hrtimer *timer) @@ -454,35 +473,43 @@ static inline void debug_deactivate(struct hrtimer *timer) trace_hrtimer_cancel(timer); } -#if defined(CONFIG_NO_HZ_COMMON) || defined(CONFIG_HIGH_RES_TIMERS) -static inline void hrtimer_update_next_timer(struct hrtimer_cpu_base *cpu_base, - struct hrtimer *timer) +static struct hrtimer_clock_base * +__next_base(struct hrtimer_cpu_base *cpu_base, unsigned int *active) { -#ifdef CONFIG_HIGH_RES_TIMERS - cpu_base->next_timer = timer; -#endif + unsigned int idx; + + if (!*active) + return NULL; + + idx = __ffs(*active); + *active &= ~(1U << idx); + + return &cpu_base->clock_base[idx]; } -static ktime_t __hrtimer_get_next_event(struct hrtimer_cpu_base *cpu_base) +#define for_each_active_base(base, cpu_base, active) \ + while ((base = __next_base((cpu_base), &(active)))) + +static ktime_t __hrtimer_next_event_base(struct hrtimer_cpu_base *cpu_base, + unsigned int active, + ktime_t expires_next) { - struct hrtimer_clock_base *base = cpu_base->clock_base; - unsigned int active = cpu_base->active_bases; - ktime_t expires, expires_next = KTIME_MAX; + struct hrtimer_clock_base *base; + ktime_t expires; - hrtimer_update_next_timer(cpu_base, NULL); - for (; active; base++, active >>= 1) { + for_each_active_base(base, cpu_base, active) { struct timerqueue_node *next; struct hrtimer *timer; - if (!(active & 0x01)) - continue; - next = timerqueue_getnext(&base->active); timer = container_of(next, struct hrtimer, node); expires = ktime_sub(hrtimer_get_expires(timer), base->offset); if (expires < expires_next) { expires_next = expires; - hrtimer_update_next_timer(cpu_base, timer); + if (timer->is_soft) + cpu_base->softirq_next_timer = timer; + else + cpu_base->next_timer = timer; } } /* @@ -494,7 +521,47 @@ static ktime_t __hrtimer_get_next_event(struct hrtimer_cpu_base *cpu_base) expires_next = 0; return expires_next; } -#endif + +/* + * Recomputes cpu_base::*next_timer and returns the earliest expires_next but + * does not set cpu_base::*expires_next, that is done by hrtimer_reprogram. + * + * When a softirq is pending, we can ignore the HRTIMER_ACTIVE_SOFT bases, + * those timers will get run whenever the softirq gets handled, at the end of + * hrtimer_run_softirq(), hrtimer_update_softirq_timer() will re-add these bases. + * + * Therefore softirq values are those from the HRTIMER_ACTIVE_SOFT clock bases. + * The !softirq values are the minima across HRTIMER_ACTIVE_ALL, unless an actual + * softirq is pending, in which case they're the minima of HRTIMER_ACTIVE_HARD. + * + * @active_mask must be one of: + * - HRTIMER_ACTIVE_ALL, + * - HRTIMER_ACTIVE_SOFT, or + * - HRTIMER_ACTIVE_HARD. + */ +static ktime_t +__hrtimer_get_next_event(struct hrtimer_cpu_base *cpu_base, unsigned int active_mask) +{ + unsigned int active; + struct hrtimer *next_timer = NULL; + ktime_t expires_next = KTIME_MAX; + + if (!cpu_base->softirq_activated && (active_mask & HRTIMER_ACTIVE_SOFT)) { + active = cpu_base->active_bases & HRTIMER_ACTIVE_SOFT; + cpu_base->softirq_next_timer = NULL; + expires_next = __hrtimer_next_event_base(cpu_base, active, KTIME_MAX); + + next_timer = cpu_base->softirq_next_timer; + } + + if (active_mask & HRTIMER_ACTIVE_HARD) { + active = cpu_base->active_bases & HRTIMER_ACTIVE_HARD; + cpu_base->next_timer = next_timer; + expires_next = __hrtimer_next_event_base(cpu_base, active, expires_next); + } + + return expires_next; +} static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base) { @@ -502,36 +569,14 @@ static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base) ktime_t *offs_boot = &base->clock_base[HRTIMER_BASE_BOOTTIME].offset; ktime_t *offs_tai = &base->clock_base[HRTIMER_BASE_TAI].offset; - return ktime_get_update_offsets_now(&base->clock_was_set_seq, + ktime_t now = ktime_get_update_offsets_now(&base->clock_was_set_seq, offs_real, offs_boot, offs_tai); -} -/* High resolution timer related functions */ -#ifdef CONFIG_HIGH_RES_TIMERS - -/* - * High resolution timer enabled ? - */ -static bool hrtimer_hres_enabled __read_mostly = true; -unsigned int hrtimer_resolution __read_mostly = LOW_RES_NSEC; -EXPORT_SYMBOL_GPL(hrtimer_resolution); - -/* - * Enable / Disable high resolution mode - */ -static int __init setup_hrtimer_hres(char *str) -{ - return (kstrtobool(str, &hrtimer_hres_enabled) == 0); -} - -__setup("highres=", setup_hrtimer_hres); + base->clock_base[HRTIMER_BASE_REALTIME_SOFT].offset = *offs_real; + base->clock_base[HRTIMER_BASE_BOOTTIME_SOFT].offset = *offs_boot; + base->clock_base[HRTIMER_BASE_TAI_SOFT].offset = *offs_tai; -/* - * hrtimer_high_res_enabled - query, if the highres mode is enabled - */ -static inline int hrtimer_is_hres_enabled(void) -{ - return hrtimer_hres_enabled; + return now; } /* @@ -539,7 +584,8 @@ static inline int hrtimer_is_hres_enabled(void) */ static inline int __hrtimer_hres_active(struct hrtimer_cpu_base *cpu_base) { - return cpu_base->hres_active; + return IS_ENABLED(CONFIG_HIGH_RES_TIMERS) ? + cpu_base->hres_active : 0; } static inline int hrtimer_hres_active(void) @@ -557,10 +603,23 @@ hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base, int skip_equal) { ktime_t expires_next; - if (!cpu_base->hres_active) - return; + /* + * Find the current next expiration time. + */ + expires_next = __hrtimer_get_next_event(cpu_base, HRTIMER_ACTIVE_ALL); - expires_next = __hrtimer_get_next_event(cpu_base); + if (cpu_base->next_timer && cpu_base->next_timer->is_soft) { + /* + * When the softirq is activated, hrtimer has to be + * programmed with the first hard hrtimer because soft + * timer interrupt could occur too late. + */ + if (cpu_base->softirq_activated) + expires_next = __hrtimer_get_next_event(cpu_base, + HRTIMER_ACTIVE_HARD); + else + cpu_base->softirq_expires_next = expires_next; + } if (skip_equal && expires_next == cpu_base->expires_next) return; @@ -568,6 +627,9 @@ hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base, int skip_equal) cpu_base->expires_next = expires_next; /* + * If hres is not active, hardware does not have to be + * reprogrammed yet. + * * If a hang was detected in the last timer interrupt then we * leave the hang delay active in the hardware. We want the * system to make progress. That also prevents the following @@ -581,81 +643,38 @@ hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base, int skip_equal) * set. So we'd effectivly block all timers until the T2 event * fires. */ - if (cpu_base->hang_detected) + if (!__hrtimer_hres_active(cpu_base) || cpu_base->hang_detected) return; tick_program_event(cpu_base->expires_next, 1); } +/* High resolution timer related functions */ +#ifdef CONFIG_HIGH_RES_TIMERS + /* - * When a timer is enqueued and expires earlier than the already enqueued - * timers, we have to check, whether it expires earlier than the timer for - * which the clock event device was armed. - * - * Called with interrupts disabled and base->cpu_base.lock held + * High resolution timer enabled ? */ -static void hrtimer_reprogram(struct hrtimer *timer, - struct hrtimer_clock_base *base) -{ - struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases); - ktime_t expires = ktime_sub(hrtimer_get_expires(timer), base->offset); - - WARN_ON_ONCE(hrtimer_get_expires_tv64(timer) < 0); - - /* - * If the timer is not on the current cpu, we cannot reprogram - * the other cpus clock event device. - */ - if (base->cpu_base != cpu_base) - return; - - /* - * If the hrtimer interrupt is running, then it will - * reevaluate the clock bases and reprogram the clock event - * device. The callbacks are always executed in hard interrupt - * context so we don't need an extra check for a running - * callback. - */ - if (cpu_base->in_hrtirq) - return; - - /* - * CLOCK_REALTIME timer might be requested with an absolute - * expiry time which is less than base->offset. Set it to 0. - */ - if (expires < 0) - expires = 0; - - if (expires >= cpu_base->expires_next) - return; - - /* Update the pointer to the next expiring timer */ - cpu_base->next_timer = timer; - - /* - * If a hang was detected in the last timer interrupt then we - * do not schedule a timer which is earlier than the expiry - * which we enforced in the hang detection. We want the system - * to make progress. - */ - if (cpu_base->hang_detected) - return; +static bool hrtimer_hres_enabled __read_mostly = true; +unsigned int hrtimer_resolution __read_mostly = LOW_RES_NSEC; +EXPORT_SYMBOL_GPL(hrtimer_resolution); - /* - * Program the timer hardware. We enforce the expiry for - * events which are already in the past. - */ - cpu_base->expires_next = expires; - tick_program_event(expires, 1); +/* + * Enable / Disable high resolution mode + */ +static int __init setup_hrtimer_hres(char *str) +{ + return (kstrtobool(str, &hrtimer_hres_enabled) == 0); } +__setup("highres=", setup_hrtimer_hres); + /* - * Initialize the high resolution related parts of cpu_base + * hrtimer_high_res_enabled - query, if the highres mode is enabled */ -static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) +static inline int hrtimer_is_hres_enabled(void) { - base->expires_next = KTIME_MAX; - base->hres_active = 0; + return hrtimer_hres_enabled; } /* @@ -667,7 +686,7 @@ static void retrigger_next_event(void *arg) { struct hrtimer_cpu_base *base = this_cpu_ptr(&hrtimer_bases); - if (!base->hres_active) + if (!__hrtimer_hres_active(base)) return; raw_spin_lock(&base->lock); @@ -714,23 +733,102 @@ void clock_was_set_delayed(void) #else -static inline int __hrtimer_hres_active(struct hrtimer_cpu_base *b) { return 0; } -static inline int hrtimer_hres_active(void) { return 0; } static inline int hrtimer_is_hres_enabled(void) { return 0; } static inline void hrtimer_switch_to_hres(void) { } -static inline void -hrtimer_force_reprogram(struct hrtimer_cpu_base *base, int skip_equal) { } -static inline int hrtimer_reprogram(struct hrtimer *timer, - struct hrtimer_clock_base *base) -{ - return 0; -} -static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) { } static inline void retrigger_next_event(void *arg) { } #endif /* CONFIG_HIGH_RES_TIMERS */ /* + * When a timer is enqueued and expires earlier than the already enqueued + * timers, we have to check, whether it expires earlier than the timer for + * which the clock event device was armed. + * + * Called with interrupts disabled and base->cpu_base.lock held + */ +static void hrtimer_reprogram(struct hrtimer *timer, bool reprogram) +{ + struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases); + struct hrtimer_clock_base *base = timer->base; + ktime_t expires = ktime_sub(hrtimer_get_expires(timer), base->offset); + + WARN_ON_ONCE(hrtimer_get_expires_tv64(timer) < 0); + + /* + * CLOCK_REALTIME timer might be requested with an absolute + * expiry time which is less than base->offset. Set it to 0. + */ + if (expires < 0) + expires = 0; + + if (timer->is_soft) { + /* + * soft hrtimer could be started on a remote CPU. In this + * case softirq_expires_next needs to be updated on the + * remote CPU. The soft hrtimer will not expire before the + * first hard hrtimer on the remote CPU - + * hrtimer_check_target() prevents this case. + */ + struct hrtimer_cpu_base *timer_cpu_base = base->cpu_base; + + if (timer_cpu_base->softirq_activated) + return; + + if (!ktime_before(expires, timer_cpu_base->softirq_expires_next)) + return; + + timer_cpu_base->softirq_next_timer = timer; + timer_cpu_base->softirq_expires_next = expires; + + if (!ktime_before(expires, timer_cpu_base->expires_next) || + !reprogram) + return; + } + + /* + * If the timer is not on the current cpu, we cannot reprogram + * the other cpus clock event device. + */ + if (base->cpu_base != cpu_base) + return; + + /* + * If the hrtimer interrupt is running, then it will + * reevaluate the clock bases and reprogram the clock event + * device. The callbacks are always executed in hard interrupt + * context so we don't need an extra check for a running + * callback. + */ + if (cpu_base->in_hrtirq) + return; + + if (expires >= cpu_base->expires_next) + return; + + /* Update the pointer to the next expiring timer */ + cpu_base->next_timer = timer; + cpu_base->expires_next = expires; + + /* + * If hres is not active, hardware does not have to be + * programmed yet. + * + * If a hang was detected in the last timer interrupt then we + * do not schedule a timer which is earlier than the expiry + * which we enforced in the hang detection. We want the system + * to make progress. + */ + if (!__hrtimer_hres_active(cpu_base) || cpu_base->hang_detected) + return; + + /* + * Program the timer hardware. We enforce the expiry for + * events which are already in the past. + */ + tick_program_event(expires, 1); +} + +/* * Clock realtime was set * * Change the offset of the realtime clock vs. the monotonic @@ -835,9 +933,10 @@ EXPORT_SYMBOL_GPL(hrtimer_forward); * Returns 1 when the new timer is the leftmost timer in the tree. */ static int enqueue_hrtimer(struct hrtimer *timer, - struct hrtimer_clock_base *base) + struct hrtimer_clock_base *base, + enum hrtimer_mode mode) { - debug_activate(timer); + debug_activate(timer, mode); base->cpu_base->active_bases |= 1 << base->index; @@ -870,7 +969,6 @@ static void __remove_hrtimer(struct hrtimer *timer, if (!timerqueue_del(&base->active, &timer->node)) cpu_base->active_bases &= ~(1 << base->index); -#ifdef CONFIG_HIGH_RES_TIMERS /* * Note: If reprogram is false we do not update * cpu_base->next_timer. This happens when we remove the first @@ -881,7 +979,6 @@ static void __remove_hrtimer(struct hrtimer *timer, */ if (reprogram && timer == cpu_base->next_timer) hrtimer_force_reprogram(cpu_base, 1); -#endif } /* @@ -930,22 +1027,36 @@ static inline ktime_t hrtimer_update_lowres(struct hrtimer *timer, ktime_t tim, return tim; } -/** - * hrtimer_start_range_ns - (re)start an hrtimer on the current CPU - * @timer: the timer to be added - * @tim: expiry time - * @delta_ns: "slack" range for the timer - * @mode: expiry mode: absolute (HRTIMER_MODE_ABS) or - * relative (HRTIMER_MODE_REL) - */ -void hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim, - u64 delta_ns, const enum hrtimer_mode mode) +static void +hrtimer_update_softirq_timer(struct hrtimer_cpu_base *cpu_base, bool reprogram) { - struct hrtimer_clock_base *base, *new_base; - unsigned long flags; - int leftmost; + ktime_t expires; - base = lock_hrtimer_base(timer, &flags); + /* + * Find the next SOFT expiration. + */ + expires = __hrtimer_get_next_event(cpu_base, HRTIMER_ACTIVE_SOFT); + + /* + * reprogramming needs to be triggered, even if the next soft + * hrtimer expires at the same time than the next hard + * hrtimer. cpu_base->softirq_expires_next needs to be updated! + */ + if (expires == KTIME_MAX) + return; + + /* + * cpu_base->*next_timer is recomputed by __hrtimer_get_next_event() + * cpu_base->*expires_next is only set by hrtimer_reprogram() + */ + hrtimer_reprogram(cpu_base->softirq_next_timer, reprogram); +} + +static int __hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim, + u64 delta_ns, const enum hrtimer_mode mode, + struct hrtimer_clock_base *base) +{ + struct hrtimer_clock_base *new_base; /* Remove an active timer from the queue: */ remove_hrtimer(timer, base, true); @@ -960,21 +1071,35 @@ void hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim, /* Switch the timer base, if necessary: */ new_base = switch_hrtimer_base(timer, base, mode & HRTIMER_MODE_PINNED); - leftmost = enqueue_hrtimer(timer, new_base); - if (!leftmost) - goto unlock; + return enqueue_hrtimer(timer, new_base, mode); +} + +/** + * hrtimer_start_range_ns - (re)start an hrtimer + * @timer: the timer to be added + * @tim: expiry time + * @delta_ns: "slack" range for the timer + * @mode: timer mode: absolute (HRTIMER_MODE_ABS) or + * relative (HRTIMER_MODE_REL), and pinned (HRTIMER_MODE_PINNED); + * softirq based mode is considered for debug purpose only! + */ +void hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim, + u64 delta_ns, const enum hrtimer_mode mode) +{ + struct hrtimer_clock_base *base; + unsigned long flags; + + /* + * Check whether the HRTIMER_MODE_SOFT bit and hrtimer.is_soft + * match. + */ + WARN_ON_ONCE(!(mode & HRTIMER_MODE_SOFT) ^ !timer->is_soft); + + base = lock_hrtimer_base(timer, &flags); + + if (__hrtimer_start_range_ns(timer, tim, delta_ns, mode, base)) + hrtimer_reprogram(timer, true); - if (!hrtimer_is_hres_active(timer)) { - /* - * Kick to reschedule the next tick to handle the new timer - * on dynticks target. - */ - if (new_base->cpu_base->nohz_active) - wake_up_nohz_cpu(new_base->cpu_base->cpu); - } else { - hrtimer_reprogram(timer, new_base); - } -unlock: unlock_hrtimer_base(timer, &flags); } EXPORT_SYMBOL_GPL(hrtimer_start_range_ns); @@ -1072,7 +1197,7 @@ u64 hrtimer_get_next_event(void) raw_spin_lock_irqsave(&cpu_base->lock, flags); if (!__hrtimer_hres_active(cpu_base)) - expires = __hrtimer_get_next_event(cpu_base); + expires = __hrtimer_get_next_event(cpu_base, HRTIMER_ACTIVE_ALL); raw_spin_unlock_irqrestore(&cpu_base->lock, flags); @@ -1095,17 +1220,24 @@ static inline int hrtimer_clockid_to_base(clockid_t clock_id) static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id, enum hrtimer_mode mode) { + bool softtimer = !!(mode & HRTIMER_MODE_SOFT); + int base = softtimer ? HRTIMER_MAX_CLOCK_BASES / 2 : 0; struct hrtimer_cpu_base *cpu_base; - int base; memset(timer, 0, sizeof(struct hrtimer)); cpu_base = raw_cpu_ptr(&hrtimer_bases); - if (clock_id == CLOCK_REALTIME && mode != HRTIMER_MODE_ABS) + /* + * POSIX magic: Relative CLOCK_REALTIME timers are not affected by + * clock modifications, so they needs to become CLOCK_MONOTONIC to + * ensure POSIX compliance. + */ + if (clock_id == CLOCK_REALTIME && mode & HRTIMER_MODE_REL) clock_id = CLOCK_MONOTONIC; - base = hrtimer_clockid_to_base(clock_id); + base += hrtimer_clockid_to_base(clock_id); + timer->is_soft = softtimer; timer->base = &cpu_base->clock_base[base]; timerqueue_init(&timer->node); } @@ -1114,7 +1246,13 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id, * hrtimer_init - initialize a timer to the given clock * @timer: the timer to be initialized * @clock_id: the clock to be used - * @mode: timer mode abs/rel + * @mode: The modes which are relevant for intitialization: + * HRTIMER_MODE_ABS, HRTIMER_MODE_REL, HRTIMER_MODE_ABS_SOFT, + * HRTIMER_MODE_REL_SOFT + * + * The PINNED variants of the above can be handed in, + * but the PINNED bit is ignored as pinning happens + * when the hrtimer is started */ void hrtimer_init(struct hrtimer *timer, clockid_t clock_id, enum hrtimer_mode mode) @@ -1133,19 +1271,19 @@ EXPORT_SYMBOL_GPL(hrtimer_init); */ bool hrtimer_active(const struct hrtimer *timer) { - struct hrtimer_cpu_base *cpu_base; + struct hrtimer_clock_base *base; unsigned int seq; do { - cpu_base = READ_ONCE(timer->base->cpu_base); - seq = raw_read_seqcount_begin(&cpu_base->seq); + base = READ_ONCE(timer->base); + seq = raw_read_seqcount_begin(&base->seq); if (timer->state != HRTIMER_STATE_INACTIVE || - cpu_base->running == timer) + base->running == timer) return true; - } while (read_seqcount_retry(&cpu_base->seq, seq) || - cpu_base != READ_ONCE(timer->base->cpu_base)); + } while (read_seqcount_retry(&base->seq, seq) || + base != READ_ONCE(timer->base)); return false; } @@ -1171,7 +1309,8 @@ EXPORT_SYMBOL_GPL(hrtimer_active); static void __run_hrtimer(struct hrtimer_cpu_base *cpu_base, struct hrtimer_clock_base *base, - struct hrtimer *timer, ktime_t *now) + struct hrtimer *timer, ktime_t *now, + unsigned long flags) { enum hrtimer_restart (*fn)(struct hrtimer *); int restart; @@ -1179,16 +1318,16 @@ static void __run_hrtimer(struct hrtimer_cpu_base *cpu_base, lockdep_assert_held(&cpu_base->lock); debug_deactivate(timer); - cpu_base->running = timer; + base->running = timer; /* * Separate the ->running assignment from the ->state assignment. * * As with a regular write barrier, this ensures the read side in - * hrtimer_active() cannot observe cpu_base->running == NULL && + * hrtimer_active() cannot observe base->running == NULL && * timer->state == INACTIVE. */ - raw_write_seqcount_barrier(&cpu_base->seq); + raw_write_seqcount_barrier(&base->seq); __remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE, 0); fn = timer->function; @@ -1202,15 +1341,15 @@ static void __run_hrtimer(struct hrtimer_cpu_base *cpu_base, timer->is_rel = false; /* - * Because we run timers from hardirq context, there is no chance - * they get migrated to another cpu, therefore its safe to unlock - * the timer base. + * The timer is marked as running in the CPU base, so it is + * protected against migration to a different CPU even if the lock + * is dropped. */ - raw_spin_unlock(&cpu_base->lock); + raw_spin_unlock_irqrestore(&cpu_base->lock, flags); trace_hrtimer_expire_entry(timer, now); restart = fn(timer); trace_hrtimer_expire_exit(timer); - raw_spin_lock(&cpu_base->lock); + raw_spin_lock_irq(&cpu_base->lock); /* * Note: We clear the running state after enqueue_hrtimer and @@ -1223,33 +1362,31 @@ static void __run_hrtimer(struct hrtimer_cpu_base *cpu_base, */ if (restart != HRTIMER_NORESTART && !(timer->state & HRTIMER_STATE_ENQUEUED)) - enqueue_hrtimer(timer, base); + enqueue_hrtimer(timer, base, HRTIMER_MODE_ABS); /* * Separate the ->running assignment from the ->state assignment. * * As with a regular write barrier, this ensures the read side in - * hrtimer_active() cannot observe cpu_base->running == NULL && + * hrtimer_active() cannot observe base->running.timer == NULL && * timer->state == INACTIVE. */ - raw_write_seqcount_barrier(&cpu_base->seq); + raw_write_seqcount_barrier(&base->seq); - WARN_ON_ONCE(cpu_base->running != timer); - cpu_base->running = NULL; + WARN_ON_ONCE(base->running != timer); + base->running = NULL; } -static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now) +static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now, + unsigned long flags, unsigned int active_mask) { - struct hrtimer_clock_base *base = cpu_base->clock_base; - unsigned int active = cpu_base->active_bases; + struct hrtimer_clock_base *base; + unsigned int active = cpu_base->active_bases & active_mask; - for (; active; base++, active >>= 1) { + for_each_active_base(base, cpu_base, active) { struct timerqueue_node *node; ktime_t basenow; - if (!(active & 0x01)) - continue; - basenow = ktime_add(now, base->offset); while ((node = timerqueue_getnext(&base->active))) { @@ -1272,11 +1409,28 @@ static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now) if (basenow < hrtimer_get_softexpires_tv64(timer)) break; - __run_hrtimer(cpu_base, base, timer, &basenow); + __run_hrtimer(cpu_base, base, timer, &basenow, flags); } } } +static __latent_entropy void hrtimer_run_softirq(struct softirq_action *h) +{ + struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases); + unsigned long flags; + ktime_t now; + + raw_spin_lock_irqsave(&cpu_base->lock, flags); + + now = hrtimer_update_base(cpu_base); + __hrtimer_run_queues(cpu_base, now, flags, HRTIMER_ACTIVE_SOFT); + + cpu_base->softirq_activated = 0; + hrtimer_update_softirq_timer(cpu_base, true); + + raw_spin_unlock_irqrestore(&cpu_base->lock, flags); +} + #ifdef CONFIG_HIGH_RES_TIMERS /* @@ -1287,13 +1441,14 @@ void hrtimer_interrupt(struct clock_event_device *dev) { struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases); ktime_t expires_next, now, entry_time, delta; + unsigned long flags; int retries = 0; BUG_ON(!cpu_base->hres_active); cpu_base->nr_events++; dev->next_event = KTIME_MAX; - raw_spin_lock(&cpu_base->lock); + raw_spin_lock_irqsave(&cpu_base->lock, flags); entry_time = now = hrtimer_update_base(cpu_base); retry: cpu_base->in_hrtirq = 1; @@ -1306,17 +1461,23 @@ retry: */ cpu_base->expires_next = KTIME_MAX; - __hrtimer_run_queues(cpu_base, now); + if (!ktime_before(now, cpu_base->softirq_expires_next)) { + cpu_base->softirq_expires_next = KTIME_MAX; + cpu_base->softirq_activated = 1; + raise_softirq_irqoff(HRTIMER_SOFTIRQ); + } + + __hrtimer_run_queues(cpu_base, now, flags, HRTIMER_ACTIVE_HARD); /* Reevaluate the clock bases for the next expiry */ - expires_next = __hrtimer_get_next_event(cpu_base); + expires_next = __hrtimer_get_next_event(cpu_base, HRTIMER_ACTIVE_ALL); /* * Store the new expiry value so the migration code can verify * against it. */ cpu_base->expires_next = expires_next; cpu_base->in_hrtirq = 0; - raw_spin_unlock(&cpu_base->lock); + raw_spin_unlock_irqrestore(&cpu_base->lock, flags); /* Reprogramming necessary ? */ if (!tick_program_event(expires_next, 0)) { @@ -1337,7 +1498,7 @@ retry: * Acquire base lock for updating the offsets and retrieving * the current time. */ - raw_spin_lock(&cpu_base->lock); + raw_spin_lock_irqsave(&cpu_base->lock, flags); now = hrtimer_update_base(cpu_base); cpu_base->nr_retries++; if (++retries < 3) @@ -1350,7 +1511,8 @@ retry: */ cpu_base->nr_hangs++; cpu_base->hang_detected = 1; - raw_spin_unlock(&cpu_base->lock); + raw_spin_unlock_irqrestore(&cpu_base->lock, flags); + delta = ktime_sub(now, entry_time); if ((unsigned int)delta > cpu_base->max_hang_time) cpu_base->max_hang_time = (unsigned int) delta; @@ -1392,6 +1554,7 @@ static inline void __hrtimer_peek_ahead_timers(void) { } void hrtimer_run_queues(void) { struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases); + unsigned long flags; ktime_t now; if (__hrtimer_hres_active(cpu_base)) @@ -1409,10 +1572,17 @@ void hrtimer_run_queues(void) return; } - raw_spin_lock(&cpu_base->lock); + raw_spin_lock_irqsave(&cpu_base->lock, flags); now = hrtimer_update_base(cpu_base); - __hrtimer_run_queues(cpu_base, now); - raw_spin_unlock(&cpu_base->lock); + + if (!ktime_before(now, cpu_base->softirq_expires_next)) { + cpu_base->softirq_expires_next = KTIME_MAX; + cpu_base->softirq_activated = 1; + raise_softirq_irqoff(HRTIMER_SOFTIRQ); + } + + __hrtimer_run_queues(cpu_base, now, flags, HRTIMER_ACTIVE_HARD); + raw_spin_unlock_irqrestore(&cpu_base->lock, flags); } /* @@ -1590,7 +1760,13 @@ int hrtimers_prepare_cpu(unsigned int cpu) } cpu_base->cpu = cpu; - hrtimer_init_hres(cpu_base); + cpu_base->active_bases = 0; + cpu_base->hres_active = 0; + cpu_base->hang_detected = 0; + cpu_base->next_timer = NULL; + cpu_base->softirq_next_timer = NULL; + cpu_base->expires_next = KTIME_MAX; + cpu_base->softirq_expires_next = KTIME_MAX; return 0; } @@ -1622,7 +1798,7 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base, * sort out already expired timers and reprogram the * event device. */ - enqueue_hrtimer(timer, new_base); + enqueue_hrtimer(timer, new_base, HRTIMER_MODE_ABS); } } @@ -1634,6 +1810,12 @@ int hrtimers_dead_cpu(unsigned int scpu) BUG_ON(cpu_online(scpu)); tick_cancel_sched_timer(scpu); + /* + * this BH disable ensures that raise_softirq_irqoff() does + * not wakeup ksoftirqd (and acquire the pi-lock) while + * holding the cpu_base lock + */ + local_bh_disable(); local_irq_disable(); old_base = &per_cpu(hrtimer_bases, scpu); new_base = this_cpu_ptr(&hrtimer_bases); @@ -1649,12 +1831,19 @@ int hrtimers_dead_cpu(unsigned int scpu) &new_base->clock_base[i]); } + /* + * The migration might have changed the first expiring softirq + * timer on this CPU. Update it. + */ + hrtimer_update_softirq_timer(new_base, false); + raw_spin_unlock(&old_base->lock); raw_spin_unlock(&new_base->lock); /* Check, if we got expired work to do */ __hrtimer_peek_ahead_timers(); local_irq_enable(); + local_bh_enable(); return 0; } @@ -1663,18 +1852,19 @@ int hrtimers_dead_cpu(unsigned int scpu) void __init hrtimers_init(void) { hrtimers_prepare_cpu(smp_processor_id()); + open_softirq(HRTIMER_SOFTIRQ, hrtimer_run_softirq); } /** * schedule_hrtimeout_range_clock - sleep until timeout * @expires: timeout value (ktime_t) * @delta: slack in expires timeout (ktime_t) - * @mode: timer mode, HRTIMER_MODE_ABS or HRTIMER_MODE_REL - * @clock: timer clock, CLOCK_MONOTONIC or CLOCK_REALTIME + * @mode: timer mode + * @clock_id: timer clock to be used */ int __sched schedule_hrtimeout_range_clock(ktime_t *expires, u64 delta, - const enum hrtimer_mode mode, int clock) + const enum hrtimer_mode mode, clockid_t clock_id) { struct hrtimer_sleeper t; @@ -1695,7 +1885,7 @@ schedule_hrtimeout_range_clock(ktime_t *expires, u64 delta, return -EINTR; } - hrtimer_init_on_stack(&t.timer, clock, mode); + hrtimer_init_on_stack(&t.timer, clock_id, mode); hrtimer_set_expires_range_ns(&t.timer, *expires, delta); hrtimer_init_sleeper(&t, current); @@ -1717,7 +1907,7 @@ schedule_hrtimeout_range_clock(ktime_t *expires, u64 delta, * schedule_hrtimeout_range - sleep until timeout * @expires: timeout value (ktime_t) * @delta: slack in expires timeout (ktime_t) - * @mode: timer mode, HRTIMER_MODE_ABS or HRTIMER_MODE_REL + * @mode: timer mode * * Make the current task sleep until the given expiry time has * elapsed. The routine will return immediately unless @@ -1756,7 +1946,7 @@ EXPORT_SYMBOL_GPL(schedule_hrtimeout_range); /** * schedule_hrtimeout - sleep until timeout * @expires: timeout value (ktime_t) - * @mode: timer mode, HRTIMER_MODE_ABS or HRTIMER_MODE_REL + * @mode: timer mode * * Make the current task sleep until the given expiry time has * elapsed. The routine will return immediately unless diff --git a/kernel/time/posix-clock.c b/kernel/time/posix-clock.c index 17cdc554c9fe..94ad46d50b56 100644 --- a/kernel/time/posix-clock.c +++ b/kernel/time/posix-clock.c @@ -68,10 +68,10 @@ static ssize_t posix_clock_read(struct file *fp, char __user *buf, return err; } -static unsigned int posix_clock_poll(struct file *fp, poll_table *wait) +static __poll_t posix_clock_poll(struct file *fp, poll_table *wait) { struct posix_clock *clk = get_posix_clock(fp); - unsigned int result = 0; + __poll_t result = 0; if (!clk) return POLLERR; @@ -216,7 +216,7 @@ struct posix_clock_desc { static int get_clock_desc(const clockid_t id, struct posix_clock_desc *cd) { - struct file *fp = fget(CLOCKID_TO_FD(id)); + struct file *fp = fget(clockid_to_fd(id)); int err = -EINVAL; if (!fp) diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c index 1f27887aa194..2541bd89f20e 100644 --- a/kernel/time/posix-cpu-timers.c +++ b/kernel/time/posix-cpu-timers.c @@ -14,6 +14,7 @@ #include <linux/tick.h> #include <linux/workqueue.h> #include <linux/compat.h> +#include <linux/sched/deadline.h> #include "posix-timers.h" @@ -791,6 +792,14 @@ check_timers_list(struct list_head *timers, return 0; } +static inline void check_dl_overrun(struct task_struct *tsk) +{ + if (tsk->dl.dl_overrun) { + tsk->dl.dl_overrun = 0; + __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk); + } +} + /* * Check for any per-thread CPU timers that have fired and move them off * the tsk->cpu_timers[N] list onto the firing list. Here we update the @@ -804,6 +813,9 @@ static void check_thread_timers(struct task_struct *tsk, u64 expires; unsigned long soft; + if (dl_task(tsk)) + check_dl_overrun(tsk); + /* * If cputime_expires is zero, then there are no active * per thread CPU timers. @@ -906,6 +918,9 @@ static void check_process_timers(struct task_struct *tsk, struct task_cputime cputime; unsigned long soft; + if (dl_task(tsk)) + check_dl_overrun(tsk); + /* * If cputimer is not running, then there are no active * process wide timers (POSIX 1.b, itimers, RLIMIT_CPU). @@ -1111,6 +1126,9 @@ static inline int fastpath_timer_check(struct task_struct *tsk) return 1; } + if (dl_task(tsk) && tsk->dl.dl_overrun) + return 1; + return 0; } @@ -1189,9 +1207,8 @@ void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx, u64 now; WARN_ON_ONCE(clock_idx == CPUCLOCK_SCHED); - cpu_timer_sample_group(clock_idx, tsk, &now); - if (oldval) { + if (oldval && cpu_timer_sample_group(clock_idx, tsk, &now) != -EINVAL) { /* * We are setting itimer. The *oldval is absolute and we update * it to be relative, *newval argument is relative and we update @@ -1363,8 +1380,8 @@ static long posix_cpu_nsleep_restart(struct restart_block *restart_block) return do_cpu_nanosleep(which_clock, TIMER_ABSTIME, &t); } -#define PROCESS_CLOCK MAKE_PROCESS_CPUCLOCK(0, CPUCLOCK_SCHED) -#define THREAD_CLOCK MAKE_THREAD_CPUCLOCK(0, CPUCLOCK_SCHED) +#define PROCESS_CLOCK make_process_cpuclock(0, CPUCLOCK_SCHED) +#define THREAD_CLOCK make_thread_cpuclock(0, CPUCLOCK_SCHED) static int process_cpu_clock_getres(const clockid_t which_clock, struct timespec64 *tp) diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index ec999f32c840..75043046914e 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -462,7 +462,7 @@ static struct k_itimer * alloc_posix_timer(void) kmem_cache_free(posix_timers_cache, tmr); return NULL; } - memset(&tmr->sigq->info, 0, sizeof(siginfo_t)); + clear_siginfo(&tmr->sigq->info); return tmr; } diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index f8e1845aa464..e277284c2831 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -150,16 +150,15 @@ static inline void tick_nohz_init(void) { } #ifdef CONFIG_NO_HZ_COMMON extern unsigned long tick_nohz_active; -#else +extern void timers_update_nohz(void); +# ifdef CONFIG_SMP +extern struct static_key_false timers_migration_enabled; +# endif +#else /* CONFIG_NO_HZ_COMMON */ +static inline void timers_update_nohz(void) { } #define tick_nohz_active (0) #endif -#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) -extern void timers_update_migration(bool update_nohz); -#else -static inline void timers_update_migration(bool update_nohz) { } -#endif - DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases); extern u64 get_next_timer_interrupt(unsigned long basej, u64 basem); diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index f7cc7abfcf25..29a5733eff83 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -1107,7 +1107,7 @@ static inline void tick_nohz_activate(struct tick_sched *ts, int mode) ts->nohz_mode = mode; /* One update is enough */ if (!test_and_set_bit(0, &tick_nohz_active)) - timers_update_migration(true); + timers_update_nohz(); } /** diff --git a/kernel/time/timer.c b/kernel/time/timer.c index 0bcf00e3ce48..48150ab42de9 100644 --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -200,8 +200,6 @@ struct timer_base { unsigned long clk; unsigned long next_expiry; unsigned int cpu; - bool migration_enabled; - bool nohz_active; bool is_idle; bool must_forward_clk; DECLARE_BITMAP(pending_map, WHEEL_SIZE); @@ -210,45 +208,64 @@ struct timer_base { static DEFINE_PER_CPU(struct timer_base, timer_bases[NR_BASES]); -#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) +#ifdef CONFIG_NO_HZ_COMMON + +static DEFINE_STATIC_KEY_FALSE(timers_nohz_active); +static DEFINE_MUTEX(timer_keys_mutex); + +static void timer_update_keys(struct work_struct *work); +static DECLARE_WORK(timer_update_work, timer_update_keys); + +#ifdef CONFIG_SMP unsigned int sysctl_timer_migration = 1; -void timers_update_migration(bool update_nohz) +DEFINE_STATIC_KEY_FALSE(timers_migration_enabled); + +static void timers_update_migration(void) { - bool on = sysctl_timer_migration && tick_nohz_active; - unsigned int cpu; + if (sysctl_timer_migration && tick_nohz_active) + static_branch_enable(&timers_migration_enabled); + else + static_branch_disable(&timers_migration_enabled); +} +#else +static inline void timers_update_migration(void) { } +#endif /* !CONFIG_SMP */ - /* Avoid the loop, if nothing to update */ - if (this_cpu_read(timer_bases[BASE_STD].migration_enabled) == on) - return; +static void timer_update_keys(struct work_struct *work) +{ + mutex_lock(&timer_keys_mutex); + timers_update_migration(); + static_branch_enable(&timers_nohz_active); + mutex_unlock(&timer_keys_mutex); +} - for_each_possible_cpu(cpu) { - per_cpu(timer_bases[BASE_STD].migration_enabled, cpu) = on; - per_cpu(timer_bases[BASE_DEF].migration_enabled, cpu) = on; - per_cpu(hrtimer_bases.migration_enabled, cpu) = on; - if (!update_nohz) - continue; - per_cpu(timer_bases[BASE_STD].nohz_active, cpu) = true; - per_cpu(timer_bases[BASE_DEF].nohz_active, cpu) = true; - per_cpu(hrtimer_bases.nohz_active, cpu) = true; - } +void timers_update_nohz(void) +{ + schedule_work(&timer_update_work); } int timer_migration_handler(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { - static DEFINE_MUTEX(mutex); int ret; - mutex_lock(&mutex); + mutex_lock(&timer_keys_mutex); ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); if (!ret && write) - timers_update_migration(false); - mutex_unlock(&mutex); + timers_update_migration(); + mutex_unlock(&timer_keys_mutex); return ret; } -#endif + +static inline bool is_timers_nohz_active(void) +{ + return static_branch_unlikely(&timers_nohz_active); +} +#else +static inline bool is_timers_nohz_active(void) { return false; } +#endif /* NO_HZ_COMMON */ static unsigned long round_jiffies_common(unsigned long j, int cpu, bool force_up) @@ -534,7 +551,7 @@ __internal_add_timer(struct timer_base *base, struct timer_list *timer) static void trigger_dyntick_cpu(struct timer_base *base, struct timer_list *timer) { - if (!IS_ENABLED(CONFIG_NO_HZ_COMMON) || !base->nohz_active) + if (!is_timers_nohz_active()) return; /* @@ -849,21 +866,20 @@ static inline struct timer_base *get_timer_base(u32 tflags) return get_timer_cpu_base(tflags, tflags & TIMER_CPUMASK); } -#ifdef CONFIG_NO_HZ_COMMON static inline struct timer_base * get_target_base(struct timer_base *base, unsigned tflags) { -#ifdef CONFIG_SMP - if ((tflags & TIMER_PINNED) || !base->migration_enabled) - return get_timer_this_cpu_base(tflags); - return get_timer_cpu_base(tflags, get_nohz_timer_target()); -#else - return get_timer_this_cpu_base(tflags); +#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) + if (static_branch_likely(&timers_migration_enabled) && + !(tflags & TIMER_PINNED)) + return get_timer_cpu_base(tflags, get_nohz_timer_target()); #endif + return get_timer_this_cpu_base(tflags); } static inline void forward_timer_base(struct timer_base *base) { +#ifdef CONFIG_NO_HZ_COMMON unsigned long jnow; /* @@ -887,16 +903,8 @@ static inline void forward_timer_base(struct timer_base *base) base->clk = jnow; else base->clk = base->next_expiry; -} -#else -static inline struct timer_base * -get_target_base(struct timer_base *base, unsigned tflags) -{ - return get_timer_this_cpu_base(tflags); -} - -static inline void forward_timer_base(struct timer_base *base) { } #endif +} /* diff --git a/kernel/torture.c b/kernel/torture.c index 637e172835d8..37b94012a3f8 100644 --- a/kernel/torture.c +++ b/kernel/torture.c @@ -47,6 +47,7 @@ #include <linux/ktime.h> #include <asm/byteorder.h> #include <linux/torture.h> +#include "rcu/rcu.h" MODULE_LICENSE("GPL"); MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com>"); @@ -60,7 +61,6 @@ static bool verbose; #define FULLSTOP_RMMOD 2 /* Normal rmmod of torture. */ static int fullstop = FULLSTOP_RMMOD; static DEFINE_MUTEX(fullstop_mutex); -static int *torture_runnable; #ifdef CONFIG_HOTPLUG_CPU @@ -500,7 +500,7 @@ static int torture_shutdown(void *arg) torture_shutdown_hook(); else VERBOSE_TOROUT_STRING("No torture_shutdown_hook(), skipping."); - ftrace_dump(DUMP_ALL); + rcu_ftrace_dump(DUMP_ALL); kernel_power_off(); /* Shut down the system. */ return 0; } @@ -572,17 +572,19 @@ static int stutter; */ void stutter_wait(const char *title) { + int spt; + cond_resched_rcu_qs(); - while (READ_ONCE(stutter_pause_test) || - (torture_runnable && !READ_ONCE(*torture_runnable))) { - if (stutter_pause_test) - if (READ_ONCE(stutter_pause_test) == 1) - schedule_timeout_interruptible(1); - else - while (READ_ONCE(stutter_pause_test)) - cond_resched(); - else + spt = READ_ONCE(stutter_pause_test); + for (; spt; spt = READ_ONCE(stutter_pause_test)) { + if (spt == 1) { + schedule_timeout_interruptible(1); + } else if (spt == 2) { + while (READ_ONCE(stutter_pause_test)) + cond_resched(); + } else { schedule_timeout_interruptible(round_jiffies_relative(HZ)); + } torture_shutdown_absorb(title); } } @@ -596,17 +598,15 @@ static int torture_stutter(void *arg) { VERBOSE_TOROUT_STRING("torture_stutter task started"); do { - if (!torture_must_stop()) { - if (stutter > 1) { - schedule_timeout_interruptible(stutter - 1); - WRITE_ONCE(stutter_pause_test, 2); - } - schedule_timeout_interruptible(1); + if (!torture_must_stop() && stutter > 1) { WRITE_ONCE(stutter_pause_test, 1); + schedule_timeout_interruptible(stutter - 1); + WRITE_ONCE(stutter_pause_test, 2); + schedule_timeout_interruptible(1); } + WRITE_ONCE(stutter_pause_test, 0); if (!torture_must_stop()) schedule_timeout_interruptible(stutter); - WRITE_ONCE(stutter_pause_test, 0); torture_shutdown_absorb("torture_stutter"); } while (!torture_must_stop()); torture_kthread_stopping("torture_stutter"); @@ -647,7 +647,7 @@ static void torture_stutter_cleanup(void) * The runnable parameter points to a flag that controls whether or not * the test is currently runnable. If there is no such flag, pass in NULL. */ -bool torture_init_begin(char *ttype, bool v, int *runnable) +bool torture_init_begin(char *ttype, bool v) { mutex_lock(&fullstop_mutex); if (torture_type != NULL) { @@ -659,7 +659,6 @@ bool torture_init_begin(char *ttype, bool v, int *runnable) } torture_type = ttype; verbose = v; - torture_runnable = runnable; fullstop = FULLSTOP_DONTSTOP; return true; } diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 5af2842dea96..ca6930e0d25e 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -630,7 +630,7 @@ int ring_buffer_wait(struct ring_buffer *buffer, int cpu, bool full) * Returns POLLIN | POLLRDNORM if data exists in the buffers, * zero otherwise. */ -int ring_buffer_poll_wait(struct ring_buffer *buffer, int cpu, +__poll_t ring_buffer_poll_wait(struct ring_buffer *buffer, int cpu, struct file *filp, poll_table *poll_table) { struct ring_buffer_per_cpu *cpu_buffer; diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 8e3f20a18a06..32c069bbf41b 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2689,17 +2689,6 @@ void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, if (unlikely(in_nmi())) return; - /* - * It is possible that a function is being traced in a - * location that RCU is not watching. A call to - * rcu_irq_enter() will make sure that it is, but there's - * a few internal rcu functions that could be traced - * where that wont work either. In those cases, we just - * do nothing. - */ - if (unlikely(rcu_irq_enter_disabled())) - return; - rcu_irq_enter_irqson(); __ftrace_trace_stack(buffer, flags, skip, pc, NULL); rcu_irq_exit_irqson(); @@ -5627,7 +5616,7 @@ static int tracing_release_pipe(struct inode *inode, struct file *file) return 0; } -static unsigned int +static __poll_t trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) { struct trace_array *tr = iter->tr; @@ -5646,7 +5635,7 @@ trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_tabl filp, poll_table); } -static unsigned int +static __poll_t tracing_poll_pipe(struct file *filp, poll_table *poll_table) { struct trace_iterator *iter = filp->private_data; @@ -6600,7 +6589,7 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp) return ret; } -static unsigned int +static __poll_t tracing_buffers_poll(struct file *filp, poll_table *poll_table) { struct ftrace_buffer_info *info = filp->private_data; diff --git a/kernel/trace/trace_benchmark.c b/kernel/trace/trace_benchmark.c index 79f838a75077..22fee766081b 100644 --- a/kernel/trace/trace_benchmark.c +++ b/kernel/trace/trace_benchmark.c @@ -165,7 +165,7 @@ static int benchmark_event_kthread(void *arg) * this thread will never voluntarily schedule which would * block synchronize_rcu_tasks() indefinitely. */ - cond_resched_rcu_qs(); + cond_resched(); } return 0; diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c index 685c50ae6300..671b13457387 100644 --- a/kernel/tracepoint.c +++ b/kernel/tracepoint.c @@ -212,11 +212,10 @@ static int tracepoint_add_func(struct tracepoint *tp, } /* - * rcu_assign_pointer has a smp_wmb() which makes sure that the new - * probe callbacks array is consistent before setting a pointer to it. - * This array is referenced by __DO_TRACE from - * include/linux/tracepoints.h. A matching smp_read_barrier_depends() - * is used. + * rcu_assign_pointer has as smp_store_release() which makes sure + * that the new probe callbacks array is consistent before setting + * a pointer to it. This array is referenced by __DO_TRACE from + * include/linux/tracepoint.h using rcu_dereference_sched(). */ rcu_assign_pointer(tp->funcs, tp_funcs); if (!static_key_enabled(&tp->key)) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index f699122dab32..8dd2e66e8383 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -2136,7 +2136,7 @@ __acquires(&pool->lock) * stop_machine. At the same time, report a quiescent RCU state so * the same condition doesn't freeze RCU. */ - cond_resched_rcu_qs(); + cond_resched(); spin_lock_irq(&pool->lock); @@ -3940,6 +3940,37 @@ static int wq_clamp_max_active(int max_active, unsigned int flags, return clamp_val(max_active, 1, lim); } +/* + * Workqueues which may be used during memory reclaim should have a rescuer + * to guarantee forward progress. + */ +static int init_rescuer(struct workqueue_struct *wq) +{ + struct worker *rescuer; + int ret; + + if (!(wq->flags & WQ_MEM_RECLAIM)) + return 0; + + rescuer = alloc_worker(NUMA_NO_NODE); + if (!rescuer) + return -ENOMEM; + + rescuer->rescue_wq = wq; + rescuer->task = kthread_create(rescuer_thread, rescuer, "%s", wq->name); + ret = PTR_ERR_OR_ZERO(rescuer->task); + if (ret) { + kfree(rescuer); + return ret; + } + + wq->rescuer = rescuer; + kthread_bind_mask(rescuer->task, cpu_possible_mask); + wake_up_process(rescuer->task); + + return 0; +} + struct workqueue_struct *__alloc_workqueue_key(const char *fmt, unsigned int flags, int max_active, @@ -4002,29 +4033,8 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt, if (alloc_and_link_pwqs(wq) < 0) goto err_free_wq; - /* - * Workqueues which may be used during memory reclaim should - * have a rescuer to guarantee forward progress. - */ - if (flags & WQ_MEM_RECLAIM) { - struct worker *rescuer; - - rescuer = alloc_worker(NUMA_NO_NODE); - if (!rescuer) - goto err_destroy; - - rescuer->rescue_wq = wq; - rescuer->task = kthread_create(rescuer_thread, rescuer, "%s", - wq->name); - if (IS_ERR(rescuer->task)) { - kfree(rescuer); - goto err_destroy; - } - - wq->rescuer = rescuer; - kthread_bind_mask(rescuer->task, cpu_possible_mask); - wake_up_process(rescuer->task); - } + if (wq_online && init_rescuer(wq) < 0) + goto err_destroy; if ((wq->flags & WQ_SYSFS) && workqueue_sysfs_register(wq)) goto err_destroy; @@ -5642,6 +5652,8 @@ int __init workqueue_init(void) * archs such as power and arm64. As per-cpu pools created * previously could be missing node hint and unbound pools NUMA * affinity, fix them up. + * + * Also, while iterating workqueues, create rescuers if requested. */ wq_numa_init(); @@ -5653,8 +5665,12 @@ int __init workqueue_init(void) } } - list_for_each_entry(wq, &workqueues, list) + list_for_each_entry(wq, &workqueues, list) { wq_update_unbound_numa(wq, smp_processor_id(), true); + WARN(init_rescuer(wq), + "workqueue: failed to create early rescuer for %s", + wq->name); + } mutex_unlock(&wq_pool_mutex); |