diff options
Diffstat (limited to 'kernel')
36 files changed, 639 insertions, 141 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index d9d5648f3cdc..a184470cf9b5 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -2098,11 +2098,6 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) continue; /* get old css_set pointer */ task_lock(tsk); - if (tsk->flags & PF_EXITING) { - /* ignore this task if it's going away */ - task_unlock(tsk); - continue; - } oldcg = tsk->cgroups; get_css_set(oldcg); task_unlock(tsk); diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c index 5e828a2ca8e6..213c0351dad8 100644 --- a/kernel/cgroup_freezer.c +++ b/kernel/cgroup_freezer.c @@ -153,6 +153,13 @@ static void freezer_destroy(struct cgroup_subsys *ss, kfree(cgroup_freezer(cgroup)); } +/* task is frozen or will freeze immediately when next it gets woken */ +static bool is_task_frozen_enough(struct task_struct *task) +{ + return frozen(task) || + (task_is_stopped_or_traced(task) && freezing(task)); +} + /* * The call to cgroup_lock() in the freezer.state write method prevents * a write to that file racing against an attach, and hence the @@ -231,7 +238,7 @@ static void update_if_frozen(struct cgroup *cgroup, cgroup_iter_start(cgroup, &it); while ((task = cgroup_iter_next(cgroup, &it))) { ntotal++; - if (frozen(task)) + if (is_task_frozen_enough(task)) nfrozen++; } @@ -284,7 +291,7 @@ static int try_to_freeze_cgroup(struct cgroup *cgroup, struct freezer *freezer) while ((task = cgroup_iter_next(cgroup, &it))) { if (!freeze_task(task, true)) continue; - if (frozen(task)) + if (is_task_frozen_enough(task)) continue; if (!freezing(task) && !freezer_should_skip(task)) num_cant_freeze_now++; diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 9fe58c46a426..0b1712dba587 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -123,6 +123,19 @@ static inline struct cpuset *task_cs(struct task_struct *task) struct cpuset, css); } +#ifdef CONFIG_NUMA +static inline bool task_has_mempolicy(struct task_struct *task) +{ + return task->mempolicy; +} +#else +static inline bool task_has_mempolicy(struct task_struct *task) +{ + return false; +} +#endif + + /* bits in struct cpuset flags field */ typedef enum { CS_CPU_EXCLUSIVE, @@ -949,7 +962,7 @@ static void cpuset_migrate_mm(struct mm_struct *mm, const nodemask_t *from, static void cpuset_change_task_nodemask(struct task_struct *tsk, nodemask_t *newmems) { - bool masks_disjoint = !nodes_intersects(*newmems, tsk->mems_allowed); + bool need_loop; repeat: /* @@ -962,6 +975,14 @@ repeat: return; task_lock(tsk); + /* + * Determine if a loop is necessary if another thread is doing + * get_mems_allowed(). If at least one node remains unchanged and + * tsk does not have a mempolicy, then an empty nodemask will not be + * possible when mems_allowed is larger than a word. + */ + need_loop = task_has_mempolicy(tsk) || + !nodes_intersects(*newmems, tsk->mems_allowed); nodes_or(tsk->mems_allowed, tsk->mems_allowed, *newmems); mpol_rebind_task(tsk, newmems, MPOL_REBIND_STEP1); @@ -981,11 +1002,9 @@ repeat: /* * Allocation of memory is very fast, we needn't sleep when waiting - * for the read-side. No wait is necessary, however, if at least one - * node remains unchanged. + * for the read-side. */ - while (masks_disjoint && - ACCESS_ONCE(tsk->mems_allowed_change_disable)) { + while (need_loop && ACCESS_ONCE(tsk->mems_allowed_change_disable)) { task_unlock(tsk); if (!task_curr(tsk)) yield(); diff --git a/kernel/events/core.c b/kernel/events/core.c index 0e8457da6f95..58690af323e4 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -185,6 +185,9 @@ static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, static void update_context_time(struct perf_event_context *ctx); static u64 perf_event_time(struct perf_event *event); +static void ring_buffer_attach(struct perf_event *event, + struct ring_buffer *rb); + void __weak perf_event_print_debug(void) { } extern __weak const char *perf_pmu_name(void) @@ -2171,9 +2174,10 @@ static void perf_event_context_sched_in(struct perf_event_context *ctx, */ cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); - perf_event_sched_in(cpuctx, ctx, task); + if (ctx->nr_events) + cpuctx->task_ctx = ctx; - cpuctx->task_ctx = ctx; + perf_event_sched_in(cpuctx, cpuctx->task_ctx, task); perf_pmu_enable(ctx->pmu); perf_ctx_unlock(cpuctx, ctx); @@ -3190,12 +3194,33 @@ static unsigned int perf_poll(struct file *file, poll_table *wait) struct ring_buffer *rb; unsigned int events = POLL_HUP; + /* + * Race between perf_event_set_output() and perf_poll(): perf_poll() + * grabs the rb reference but perf_event_set_output() overrides it. + * Here is the timeline for two threads T1, T2: + * t0: T1, rb = rcu_dereference(event->rb) + * t1: T2, old_rb = event->rb + * t2: T2, event->rb = new rb + * t3: T2, ring_buffer_detach(old_rb) + * t4: T1, ring_buffer_attach(rb1) + * t5: T1, poll_wait(event->waitq) + * + * To avoid this problem, we grab mmap_mutex in perf_poll() + * thereby ensuring that the assignment of the new ring buffer + * and the detachment of the old buffer appear atomic to perf_poll() + */ + mutex_lock(&event->mmap_mutex); + rcu_read_lock(); rb = rcu_dereference(event->rb); - if (rb) + if (rb) { + ring_buffer_attach(event, rb); events = atomic_xchg(&rb->poll, 0); + } rcu_read_unlock(); + mutex_unlock(&event->mmap_mutex); + poll_wait(file, &event->waitq, wait); return events; @@ -3496,6 +3521,53 @@ unlock: return ret; } +static void ring_buffer_attach(struct perf_event *event, + struct ring_buffer *rb) +{ + unsigned long flags; + + if (!list_empty(&event->rb_entry)) + return; + + spin_lock_irqsave(&rb->event_lock, flags); + if (!list_empty(&event->rb_entry)) + goto unlock; + + list_add(&event->rb_entry, &rb->event_list); +unlock: + spin_unlock_irqrestore(&rb->event_lock, flags); +} + +static void ring_buffer_detach(struct perf_event *event, + struct ring_buffer *rb) +{ + unsigned long flags; + + if (list_empty(&event->rb_entry)) + return; + + spin_lock_irqsave(&rb->event_lock, flags); + list_del_init(&event->rb_entry); + wake_up_all(&event->waitq); + spin_unlock_irqrestore(&rb->event_lock, flags); +} + +static void ring_buffer_wakeup(struct perf_event *event) +{ + struct ring_buffer *rb; + + rcu_read_lock(); + rb = rcu_dereference(event->rb); + if (!rb) + goto unlock; + + list_for_each_entry_rcu(event, &rb->event_list, rb_entry) + wake_up_all(&event->waitq); + +unlock: + rcu_read_unlock(); +} + static void rb_free_rcu(struct rcu_head *rcu_head) { struct ring_buffer *rb; @@ -3521,9 +3593,19 @@ static struct ring_buffer *ring_buffer_get(struct perf_event *event) static void ring_buffer_put(struct ring_buffer *rb) { + struct perf_event *event, *n; + unsigned long flags; + if (!atomic_dec_and_test(&rb->refcount)) return; + spin_lock_irqsave(&rb->event_lock, flags); + list_for_each_entry_safe(event, n, &rb->event_list, rb_entry) { + list_del_init(&event->rb_entry); + wake_up_all(&event->waitq); + } + spin_unlock_irqrestore(&rb->event_lock, flags); + call_rcu(&rb->rcu_head, rb_free_rcu); } @@ -3546,6 +3628,7 @@ static void perf_mmap_close(struct vm_area_struct *vma) atomic_long_sub((size >> PAGE_SHIFT) + 1, &user->locked_vm); vma->vm_mm->pinned_vm -= event->mmap_locked; rcu_assign_pointer(event->rb, NULL); + ring_buffer_detach(event, rb); mutex_unlock(&event->mmap_mutex); ring_buffer_put(rb); @@ -3700,7 +3783,7 @@ static const struct file_operations perf_fops = { void perf_event_wakeup(struct perf_event *event) { - wake_up_all(&event->waitq); + ring_buffer_wakeup(event); if (event->pending_kill) { kill_fasync(&event->fasync, SIGIO, event->pending_kill); @@ -5822,6 +5905,8 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, INIT_LIST_HEAD(&event->group_entry); INIT_LIST_HEAD(&event->event_entry); INIT_LIST_HEAD(&event->sibling_list); + INIT_LIST_HEAD(&event->rb_entry); + init_waitqueue_head(&event->waitq); init_irq_work(&event->pending, perf_pending_event); @@ -6028,6 +6113,8 @@ set: old_rb = event->rb; rcu_assign_pointer(event->rb, rb); + if (old_rb) + ring_buffer_detach(event, old_rb); ret = 0; unlock: mutex_unlock(&event->mmap_mutex); diff --git a/kernel/events/internal.h b/kernel/events/internal.h index 09097dd8116c..64568a699375 100644 --- a/kernel/events/internal.h +++ b/kernel/events/internal.h @@ -22,6 +22,9 @@ struct ring_buffer { local_t lost; /* nr records lost */ long watermark; /* wakeup watermark */ + /* poll crap */ + spinlock_t event_lock; + struct list_head event_list; struct perf_event_mmap_page *user_page; void *data_pages[0]; diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index a2a29205cc0f..7f3011c6b57f 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -209,6 +209,9 @@ ring_buffer_init(struct ring_buffer *rb, long watermark, int flags) rb->writable = 1; atomic_set(&rb->refcount, 1); + + INIT_LIST_HEAD(&rb->event_list); + spin_lock_init(&rb->event_lock); } #ifndef CONFIG_PERF_USE_VMALLOC diff --git a/kernel/exit.c b/kernel/exit.c index d0b7d988f873..e6e01b959a0e 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -1540,8 +1540,15 @@ static int wait_consider_task(struct wait_opts *wo, int ptrace, } /* dead body doesn't have much to contribute */ - if (p->exit_state == EXIT_DEAD) + if (unlikely(p->exit_state == EXIT_DEAD)) { + /* + * But do not ignore this task until the tracer does + * wait_task_zombie()->do_notify_parent(). + */ + if (likely(!ptrace) && unlikely(ptrace_reparented(p))) + wo->notask_error = 0; return 0; + } /* slay zombie? */ if (p->exit_state == EXIT_ZOMBIE) { diff --git a/kernel/fork.c b/kernel/fork.c index ba0d17261329..da4a6a10d088 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -162,7 +162,6 @@ static void account_kernel_stack(struct thread_info *ti, int account) void free_task(struct task_struct *tsk) { - prop_local_destroy_single(&tsk->dirties); account_kernel_stack(tsk->stack, -1); free_thread_info(tsk->stack); rt_mutex_debug_task_free(tsk); @@ -274,10 +273,6 @@ static struct task_struct *dup_task_struct(struct task_struct *orig) tsk->stack = ti; - err = prop_local_init_single(&tsk->dirties); - if (err) - goto out; - setup_thread_stack(tsk, orig); clear_user_return_notifier(tsk); clear_tsk_need_resched(tsk); diff --git a/kernel/futex.c b/kernel/futex.c index ea87f4d2f455..1614be20173d 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -314,17 +314,29 @@ again: #endif lock_page(page_head); + + /* + * If page_head->mapping is NULL, then it cannot be a PageAnon + * page; but it might be the ZERO_PAGE or in the gate area or + * in a special mapping (all cases which we are happy to fail); + * or it may have been a good file page when get_user_pages_fast + * found it, but truncated or holepunched or subjected to + * invalidate_complete_page2 before we got the page lock (also + * cases which we are happy to fail). And we hold a reference, + * so refcount care in invalidate_complete_page's remove_mapping + * prevents drop_caches from setting mapping to NULL beneath us. + * + * The case we do have to guard against is when memory pressure made + * shmem_writepage move it from filecache to swapcache beneath us: + * an unlikely race, but we do need to retry for page_head->mapping. + */ if (!page_head->mapping) { + int shmem_swizzled = PageSwapCache(page_head); unlock_page(page_head); put_page(page_head); - /* - * ZERO_PAGE pages don't have a mapping. Avoid a busy loop - * trying to find one. RW mapping would have COW'd (and thus - * have a mapping) so this page is RO and won't ever change. - */ - if ((page_head == ZERO_PAGE(address))) - return -EFAULT; - goto again; + if (shmem_swizzled) + goto again; + return -EFAULT; } /* diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 422e567eecf6..ae34bf51682b 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -885,10 +885,13 @@ static void __remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base, unsigned long newstate, int reprogram) { + struct timerqueue_node *next_timer; if (!(timer->state & HRTIMER_STATE_ENQUEUED)) goto out; - if (&timer->node == timerqueue_getnext(&base->active)) { + next_timer = timerqueue_getnext(&base->active); + timerqueue_del(&base->active, &timer->node); + if (&timer->node == next_timer) { #ifdef CONFIG_HIGH_RES_TIMERS /* Reprogram the clock event device. if enabled */ if (reprogram && hrtimer_hres_active()) { @@ -901,7 +904,6 @@ static void __remove_hrtimer(struct hrtimer *timer, } #endif } - timerqueue_del(&base->active, &timer->node); if (!timerqueue_getnext(&base->active)) base->cpu_base->active_bases &= ~(1 << base->index); out: diff --git a/kernel/hung_task.c b/kernel/hung_task.c index 8b1748d0172c..2e48ec0c2e91 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -74,11 +74,17 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout) /* * Ensure the task is not frozen. - * Also, when a freshly created task is scheduled once, changes - * its state to TASK_UNINTERRUPTIBLE without having ever been - * switched out once, it musn't be checked. + * Also, skip vfork and any other user process that freezer should skip. */ - if (unlikely(t->flags & PF_FROZEN || !switch_count)) + if (unlikely(t->flags & (PF_FROZEN | PF_FREEZER_SKIP))) + return; + + /* + * When a freshly created task is scheduled once, changes its state to + * TASK_UNINTERRUPTIBLE without having ever been switched out once, it + * musn't be checked. + */ + if (unlikely(!switch_count)) return; if (switch_count != t->last_switch_count) { diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 67ce837ae52c..1da999f5e746 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -623,8 +623,9 @@ static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id) static int irq_wait_for_interrupt(struct irqaction *action) { + set_current_state(TASK_INTERRUPTIBLE); + while (!kthread_should_stop()) { - set_current_state(TASK_INTERRUPTIBLE); if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags)) { @@ -632,7 +633,9 @@ static int irq_wait_for_interrupt(struct irqaction *action) return 0; } schedule(); + set_current_state(TASK_INTERRUPTIBLE); } + __set_current_state(TASK_RUNNING); return -1; } @@ -1596,7 +1599,7 @@ int request_percpu_irq(unsigned int irq, irq_handler_t handler, return -ENOMEM; action->handler = handler; - action->flags = IRQF_PERCPU; + action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND; action->name = devname; action->percpu_dev_id = dev_id; diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c index aa57d5da18c1..dc813a948be2 100644 --- a/kernel/irq/spurious.c +++ b/kernel/irq/spurious.c @@ -84,7 +84,9 @@ static int try_one_irq(int irq, struct irq_desc *desc, bool force) */ action = desc->action; if (!action || !(action->flags & IRQF_SHARED) || - (action->flags & __IRQF_TIMER) || !action->next) + (action->flags & __IRQF_TIMER) || + (action->handler(irq, action->dev_id) == IRQ_HANDLED) || + !action->next) goto out; /* Already running on another processor */ @@ -115,7 +117,7 @@ static int misrouted_irq(int irq) struct irq_desc *desc; int i, ok = 0; - if (atomic_inc_return(&irq_poll_active) == 1) + if (atomic_inc_return(&irq_poll_active) != 1) goto out; irq_poll_cpu = smp_processor_id(); diff --git a/kernel/jump_label.c b/kernel/jump_label.c index bbdfe2a462a0..66ff7109f697 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -66,8 +66,9 @@ void jump_label_inc(struct jump_label_key *key) return; jump_label_lock(); - if (atomic_add_return(1, &key->enabled) == 1) + if (atomic_read(&key->enabled) == 0) jump_label_update(key, JUMP_LABEL_ENABLE); + atomic_inc(&key->enabled); jump_label_unlock(); } diff --git a/kernel/lockdep.c b/kernel/lockdep.c index e69434b070da..e69d633d6aa6 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -44,6 +44,7 @@ #include <linux/stringify.h> #include <linux/bitops.h> #include <linux/gfp.h> +#include <linux/kmemcheck.h> #include <asm/sections.h> @@ -430,6 +431,7 @@ unsigned int max_lockdep_depth; * about it later on, in lockdep_info(). */ static int lockdep_init_error; +static const char *lock_init_error; static unsigned long lockdep_init_trace_data[20]; static struct stack_trace lockdep_init_trace = { .max_entries = ARRAY_SIZE(lockdep_init_trace_data), @@ -567,11 +569,12 @@ static void lockdep_print_held_locks(struct task_struct *curr) } } -static void print_kernel_version(void) +static void print_kernel_ident(void) { - printk("%s %.*s\n", init_utsname()->release, + printk("%s %.*s %s\n", init_utsname()->release, (int)strcspn(init_utsname()->version, " "), - init_utsname()->version); + init_utsname()->version, + print_tainted()); } static int very_verbose(struct lock_class *class) @@ -655,6 +658,7 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass) if (unlikely(!lockdep_initialized)) { lockdep_init(); lockdep_init_error = 1; + lock_init_error = lock->name; save_stack_trace(&lockdep_init_trace); } #endif @@ -722,7 +726,7 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force) class = look_up_lock_class(lock, subclass); if (likely(class)) - return class; + goto out_set_class_cache; /* * Debug-check: all keys must be persistent! @@ -807,6 +811,7 @@ out_unlock_set: graph_unlock(); raw_local_irq_restore(flags); +out_set_class_cache: if (!subclass || force) lock->class_cache[0] = class; else if (subclass < NR_LOCKDEP_CACHING_CLASSES) @@ -1148,7 +1153,7 @@ print_circular_bug_header(struct lock_list *entry, unsigned int depth, printk("\n"); printk("======================================================\n"); printk("[ INFO: possible circular locking dependency detected ]\n"); - print_kernel_version(); + print_kernel_ident(); printk("-------------------------------------------------------\n"); printk("%s/%d is trying to acquire lock:\n", curr->comm, task_pid_nr(curr)); @@ -1487,7 +1492,7 @@ print_bad_irq_dependency(struct task_struct *curr, printk("======================================================\n"); printk("[ INFO: %s-safe -> %s-unsafe lock order detected ]\n", irqclass, irqclass); - print_kernel_version(); + print_kernel_ident(); printk("------------------------------------------------------\n"); printk("%s/%d [HC%u[%lu]:SC%u[%lu]:HE%u:SE%u] is trying to acquire:\n", curr->comm, task_pid_nr(curr), @@ -1716,7 +1721,7 @@ print_deadlock_bug(struct task_struct *curr, struct held_lock *prev, printk("\n"); printk("=============================================\n"); printk("[ INFO: possible recursive locking detected ]\n"); - print_kernel_version(); + print_kernel_ident(); printk("---------------------------------------------\n"); printk("%s/%d is trying to acquire lock:\n", curr->comm, task_pid_nr(curr)); @@ -2223,7 +2228,7 @@ print_usage_bug(struct task_struct *curr, struct held_lock *this, printk("\n"); printk("=================================\n"); printk("[ INFO: inconsistent lock state ]\n"); - print_kernel_version(); + print_kernel_ident(); printk("---------------------------------\n"); printk("inconsistent {%s} -> {%s} usage.\n", @@ -2288,7 +2293,7 @@ print_irq_inversion_bug(struct task_struct *curr, printk("\n"); printk("=========================================================\n"); printk("[ INFO: possible irq lock inversion dependency detected ]\n"); - print_kernel_version(); + print_kernel_ident(); printk("---------------------------------------------------------\n"); printk("%s/%d just changed the state of lock:\n", curr->comm, task_pid_nr(curr)); @@ -2948,7 +2953,12 @@ static int mark_lock(struct task_struct *curr, struct held_lock *this, void lockdep_init_map(struct lockdep_map *lock, const char *name, struct lock_class_key *key, int subclass) { - memset(lock, 0, sizeof(*lock)); + int i; + + kmemcheck_mark_initialized(lock, sizeof(*lock)); + + for (i = 0; i < NR_LOCKDEP_CACHING_CLASSES; i++) + lock->class_cache[i] = NULL; #ifdef CONFIG_LOCK_STAT lock->cpu = raw_smp_processor_id(); @@ -3169,6 +3179,7 @@ print_unlock_inbalance_bug(struct task_struct *curr, struct lockdep_map *lock, printk("\n"); printk("=====================================\n"); printk("[ BUG: bad unlock balance detected! ]\n"); + print_kernel_ident(); printk("-------------------------------------\n"); printk("%s/%d is trying to release lock (", curr->comm, task_pid_nr(curr)); @@ -3613,6 +3624,7 @@ print_lock_contention_bug(struct task_struct *curr, struct lockdep_map *lock, printk("\n"); printk("=================================\n"); printk("[ BUG: bad contention detected! ]\n"); + print_kernel_ident(); printk("---------------------------------\n"); printk("%s/%d is trying to contend lock (", curr->comm, task_pid_nr(curr)); @@ -3968,7 +3980,8 @@ void __init lockdep_info(void) #ifdef CONFIG_DEBUG_LOCKDEP if (lockdep_init_error) { - printk("WARNING: lockdep init error! Arch code didn't call lockdep_init() early enough?\n"); + printk("WARNING: lockdep init error! lock-%s was acquired" + "before lockdep_init\n", lock_init_error); printk("Call stack leading to lockdep invocation was:\n"); print_stack_trace(&lockdep_init_trace, 0); } @@ -3987,6 +4000,7 @@ print_freed_lock_bug(struct task_struct *curr, const void *mem_from, printk("\n"); printk("=========================\n"); printk("[ BUG: held lock freed! ]\n"); + print_kernel_ident(); printk("-------------------------\n"); printk("%s/%d is freeing memory %p-%p, with a lock still held there!\n", curr->comm, task_pid_nr(curr), mem_from, mem_to-1); @@ -4044,6 +4058,7 @@ static void print_held_locks_bug(struct task_struct *curr) printk("\n"); printk("=====================================\n"); printk("[ BUG: lock held at task exit time! ]\n"); + print_kernel_ident(); printk("-------------------------------------\n"); printk("%s/%d is exiting with locks still held!\n", curr->comm, task_pid_nr(curr)); @@ -4141,6 +4156,7 @@ void lockdep_sys_exit(void) printk("\n"); printk("================================================\n"); printk("[ BUG: lock held when returning to user space! ]\n"); + print_kernel_ident(); printk("------------------------------------------------\n"); printk("%s/%d is leaving the kernel with locks still held!\n", curr->comm, curr->pid); @@ -4160,6 +4176,7 @@ void lockdep_rcu_suspicious(const char *file, const int line, const char *s) printk("\n"); printk("===============================\n"); printk("[ INFO: suspicious RCU usage. ]\n"); + print_kernel_ident(); printk("-------------------------------\n"); printk("%s:%d %s!\n", file, line, s); printk("\nother info that might help us debug this:\n\n"); diff --git a/kernel/panic.c b/kernel/panic.c index b26593604214..3458469eb7c3 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -237,11 +237,20 @@ void add_taint(unsigned flag) * Can't trust the integrity of the kernel anymore. * We don't call directly debug_locks_off() because the issue * is not necessarily serious enough to set oops_in_progress to 1 - * Also we want to keep up lockdep for staging development and - * post-warning case. + * Also we want to keep up lockdep for staging/out-of-tree + * development and post-warning case. */ - if (flag != TAINT_CRAP && flag != TAINT_WARN && __debug_locks_off()) - printk(KERN_WARNING "Disabling lock debugging due to kernel taint\n"); + switch (flag) { + case TAINT_CRAP: + case TAINT_OOT_MODULE: + case TAINT_WARN: + case TAINT_FIRMWARE_WORKAROUND: + break; + + default: + if (__debug_locks_off()) + printk(KERN_WARNING "Disabling lock debugging due to kernel taint\n"); + } set_bit(flag, &tainted_mask); } diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index b4511b6d3ef9..a6b0503574ee 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -55,6 +55,8 @@ enum { static int hibernation_mode = HIBERNATION_SHUTDOWN; +static bool freezer_test_done; + static const struct platform_hibernation_ops *hibernation_ops; /** @@ -345,11 +347,24 @@ int hibernation_snapshot(int platform_mode) error = freeze_kernel_threads(); if (error) - goto Close; + goto Cleanup; + + if (hibernation_test(TEST_FREEZER) || + hibernation_testmode(HIBERNATION_TESTPROC)) { + + /* + * Indicate to the caller that we are returning due to a + * successful freezer test. + */ + freezer_test_done = true; + goto Cleanup; + } error = dpm_prepare(PMSG_FREEZE); - if (error) - goto Complete_devices; + if (error) { + dpm_complete(msg); + goto Cleanup; + } suspend_console(); pm_restrict_gfp_mask(); @@ -378,8 +393,6 @@ int hibernation_snapshot(int platform_mode) pm_restore_gfp_mask(); resume_console(); - - Complete_devices: dpm_complete(msg); Close: @@ -389,6 +402,10 @@ int hibernation_snapshot(int platform_mode) Recover_platform: platform_recover(platform_mode); goto Resume_devices; + + Cleanup: + swsusp_free(); + goto Close; } /** @@ -641,15 +658,13 @@ int hibernate(void) if (error) goto Finish; - if (hibernation_test(TEST_FREEZER)) - goto Thaw; - - if (hibernation_testmode(HIBERNATION_TESTPROC)) - goto Thaw; - error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM); if (error) goto Thaw; + if (freezer_test_done) { + freezer_test_done = false; + goto Thaw; + } if (in_suspend) { unsigned int flags = 0; diff --git a/kernel/power/main.c b/kernel/power/main.c index 71f49fe4377e..36e0f0903c32 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -290,13 +290,14 @@ static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) break; } - if (state < PM_SUSPEND_MAX && *s) + if (state < PM_SUSPEND_MAX && *s) { error = enter_state(state); if (error) { suspend_stats.fail++; dpm_save_failed_errno(error); } else suspend_stats.success++; + } #endif Exit: diff --git a/kernel/printk.c b/kernel/printk.c index dfd8f73dcb76..989e4a52da76 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -199,7 +199,7 @@ void __init setup_log_buf(int early) unsigned long mem; mem = memblock_alloc(new_log_buf_len, PAGE_SIZE); - if (mem == MEMBLOCK_ERROR) + if (!mem) return; new_log_buf = __va(mem); } else { @@ -1292,10 +1292,11 @@ again: raw_spin_lock(&logbuf_lock); if (con_start != log_end) retry = 1; + raw_spin_unlock_irqrestore(&logbuf_lock, flags); + if (retry && console_trylock()) goto again; - raw_spin_unlock_irqrestore(&logbuf_lock, flags); if (wake_klogd) wake_up_klogd(); } diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 24d04477b257..78ab24a7b0e4 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -96,9 +96,20 @@ void __ptrace_unlink(struct task_struct *child) */ if (!(child->flags & PF_EXITING) && (child->signal->flags & SIGNAL_STOP_STOPPED || - child->signal->group_stop_count)) + child->signal->group_stop_count)) { child->jobctl |= JOBCTL_STOP_PENDING; + /* + * This is only possible if this thread was cloned by the + * traced task running in the stopped group, set the signal + * for the future reports. + * FIXME: we should change ptrace_init_task() to handle this + * case. + */ + if (!(child->jobctl & JOBCTL_STOP_SIGMASK)) + child->jobctl |= SIGSTOP; + } + /* * If transition to TASK_STOPPED is pending or in TASK_TRACED, kick * @child in the butt. Note that @resume should be used iff @child diff --git a/kernel/rtmutex-debug.c b/kernel/rtmutex-debug.c index 8eafd1bd273e..16502d3a71c8 100644 --- a/kernel/rtmutex-debug.c +++ b/kernel/rtmutex-debug.c @@ -101,6 +101,7 @@ void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter) printk("\n============================================\n"); printk( "[ BUG: circular locking deadlock detected! ]\n"); + printk("%s\n", print_tainted()); printk( "--------------------------------------------\n"); printk("%s/%d is deadlocking current task %s/%d\n\n", task->comm, task_pid_nr(task), diff --git a/kernel/sched.c b/kernel/sched.c index 0e9344a71be3..d6b149ccf925 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -71,6 +71,7 @@ #include <linux/ctype.h> #include <linux/ftrace.h> #include <linux/slab.h> +#include <linux/init_task.h> #include <asm/tlb.h> #include <asm/irq_regs.h> @@ -4810,6 +4811,9 @@ EXPORT_SYMBOL(wait_for_completion); * This waits for either a completion of a specific task to be signaled or for a * specified timeout to expire. The timeout is in jiffies. It is not * interruptible. + * + * The return value is 0 if timed out, and positive (at least 1, or number of + * jiffies left till timeout) if completed. */ unsigned long __sched wait_for_completion_timeout(struct completion *x, unsigned long timeout) @@ -4824,6 +4828,8 @@ EXPORT_SYMBOL(wait_for_completion_timeout); * * This waits for completion of a specific task to be signaled. It is * interruptible. + * + * The return value is -ERESTARTSYS if interrupted, 0 if completed. */ int __sched wait_for_completion_interruptible(struct completion *x) { @@ -4841,6 +4847,9 @@ EXPORT_SYMBOL(wait_for_completion_interruptible); * * This waits for either a completion of a specific task to be signaled or for a * specified timeout to expire. It is interruptible. The timeout is in jiffies. + * + * The return value is -ERESTARTSYS if interrupted, 0 if timed out, + * positive (at least 1, or number of jiffies left till timeout) if completed. */ long __sched wait_for_completion_interruptible_timeout(struct completion *x, @@ -4856,6 +4865,8 @@ EXPORT_SYMBOL(wait_for_completion_interruptible_timeout); * * This waits to be signaled for completion of a specific task. It can be * interrupted by a kill signal. + * + * The return value is -ERESTARTSYS if interrupted, 0 if completed. */ int __sched wait_for_completion_killable(struct completion *x) { @@ -4874,6 +4885,9 @@ EXPORT_SYMBOL(wait_for_completion_killable); * This waits for either a completion of a specific task to be * signaled or for a specified timeout to expire. It can be * interrupted by a kill signal. The timeout is in jiffies. + * + * The return value is -ERESTARTSYS if interrupted, 0 if timed out, + * positive (at least 1, or number of jiffies left till timeout) if completed. */ long __sched wait_for_completion_killable_timeout(struct completion *x, @@ -6099,6 +6113,9 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu) */ idle->sched_class = &idle_sched_class; ftrace_graph_init_idle_task(idle, cpu); +#if defined(CONFIG_SMP) + sprintf(idle->comm, "%s/%d", INIT_TASK_COMM, cpu); +#endif } /* diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index 5c9e67923b7c..8a39fa3e3c6c 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -772,19 +772,32 @@ static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update) list_del_leaf_cfs_rq(cfs_rq); } +static inline long calc_tg_weight(struct task_group *tg, struct cfs_rq *cfs_rq) +{ + long tg_weight; + + /* + * Use this CPU's actual weight instead of the last load_contribution + * to gain a more accurate current total weight. See + * update_cfs_rq_load_contribution(). + */ + tg_weight = atomic_read(&tg->load_weight); + tg_weight -= cfs_rq->load_contribution; + tg_weight += cfs_rq->load.weight; + + return tg_weight; +} + static long calc_cfs_shares(struct cfs_rq *cfs_rq, struct task_group *tg) { - long load_weight, load, shares; + long tg_weight, load, shares; + tg_weight = calc_tg_weight(tg, cfs_rq); load = cfs_rq->load.weight; - load_weight = atomic_read(&tg->load_weight); - load_weight += load; - load_weight -= cfs_rq->load_contribution; - shares = (tg->shares * load); - if (load_weight) - shares /= load_weight; + if (tg_weight) + shares /= tg_weight; if (shares < MIN_SHARES) shares = MIN_SHARES; @@ -1743,7 +1756,7 @@ static void __return_cfs_rq_runtime(struct cfs_rq *cfs_rq) static __always_inline void return_cfs_rq_runtime(struct cfs_rq *cfs_rq) { - if (!cfs_rq->runtime_enabled || !cfs_rq->nr_running) + if (!cfs_rq->runtime_enabled || cfs_rq->nr_running) return; __return_cfs_rq_runtime(cfs_rq); @@ -2036,36 +2049,100 @@ static void task_waking_fair(struct task_struct *p) * Adding load to a group doesn't make a group heavier, but can cause movement * of group shares between cpus. Assuming the shares were perfectly aligned one * can calculate the shift in shares. + * + * Calculate the effective load difference if @wl is added (subtracted) to @tg + * on this @cpu and results in a total addition (subtraction) of @wg to the + * total group weight. + * + * Given a runqueue weight distribution (rw_i) we can compute a shares + * distribution (s_i) using: + * + * s_i = rw_i / \Sum rw_j (1) + * + * Suppose we have 4 CPUs and our @tg is a direct child of the root group and + * has 7 equal weight tasks, distributed as below (rw_i), with the resulting + * shares distribution (s_i): + * + * rw_i = { 2, 4, 1, 0 } + * s_i = { 2/7, 4/7, 1/7, 0 } + * + * As per wake_affine() we're interested in the load of two CPUs (the CPU the + * task used to run on and the CPU the waker is running on), we need to + * compute the effect of waking a task on either CPU and, in case of a sync + * wakeup, compute the effect of the current task going to sleep. + * + * So for a change of @wl to the local @cpu with an overall group weight change + * of @wl we can compute the new shares distribution (s'_i) using: + * + * s'_i = (rw_i + @wl) / (@wg + \Sum rw_j) (2) + * + * Suppose we're interested in CPUs 0 and 1, and want to compute the load + * differences in waking a task to CPU 0. The additional task changes the + * weight and shares distributions like: + * + * rw'_i = { 3, 4, 1, 0 } + * s'_i = { 3/8, 4/8, 1/8, 0 } + * + * We can then compute the difference in effective weight by using: + * + * dw_i = S * (s'_i - s_i) (3) + * + * Where 'S' is the group weight as seen by its parent. + * + * Therefore the effective change in loads on CPU 0 would be 5/56 (3/8 - 2/7) + * times the weight of the group. The effect on CPU 1 would be -4/56 (4/8 - + * 4/7) times the weight of the group. */ static long effective_load(struct task_group *tg, int cpu, long wl, long wg) { struct sched_entity *se = tg->se[cpu]; - if (!tg->parent) + if (!tg->parent) /* the trivial, non-cgroup case */ return wl; for_each_sched_entity(se) { - long lw, w; + long w, W; tg = se->my_q->tg; - w = se->my_q->load.weight; - /* use this cpu's instantaneous contribution */ - lw = atomic_read(&tg->load_weight); - lw -= se->my_q->load_contribution; - lw += w + wg; + /* + * W = @wg + \Sum rw_j + */ + W = wg + calc_tg_weight(tg, se->my_q); - wl += w; + /* + * w = rw_i + @wl + */ + w = se->my_q->load.weight + wl; - if (lw > 0 && wl < lw) - wl = (wl * tg->shares) / lw; + /* + * wl = S * s'_i; see (2) + */ + if (W > 0 && w < W) + wl = (w * tg->shares) / W; else wl = tg->shares; - /* zero point is MIN_SHARES */ + /* + * Per the above, wl is the new se->load.weight value; since + * those are clipped to [MIN_SHARES, ...) do so now. See + * calc_cfs_shares(). + */ if (wl < MIN_SHARES) wl = MIN_SHARES; + + /* + * wl = dw_i = S * (s'_i - s_i); see (3) + */ wl -= se->load.weight; + + /* + * Recursively apply this logic to all parent groups to compute + * the final effective load change on the root group. Since + * only the @tg group gets extra weight, all parent groups can + * only redistribute existing shares. @wl is the shift in shares + * resulting from this level per the above. + */ wg = 0; } @@ -2249,7 +2326,8 @@ static int select_idle_sibling(struct task_struct *p, int target) int cpu = smp_processor_id(); int prev_cpu = task_cpu(p); struct sched_domain *sd; - int i; + struct sched_group *sg; + int i, smt = 0; /* * If the task is going to be woken-up on this cpu and if it is @@ -2269,25 +2347,40 @@ static int select_idle_sibling(struct task_struct *p, int target) * Otherwise, iterate the domains and find an elegible idle cpu. */ rcu_read_lock(); +again: for_each_domain(target, sd) { + if (!smt && (sd->flags & SD_SHARE_CPUPOWER)) + continue; + + if (smt && !(sd->flags & SD_SHARE_CPUPOWER)) + break; + if (!(sd->flags & SD_SHARE_PKG_RESOURCES)) break; - for_each_cpu_and(i, sched_domain_span(sd), tsk_cpus_allowed(p)) { - if (idle_cpu(i)) { - target = i; - break; + sg = sd->groups; + do { + if (!cpumask_intersects(sched_group_cpus(sg), + tsk_cpus_allowed(p))) + goto next; + + for_each_cpu(i, sched_group_cpus(sg)) { + if (!idle_cpu(i)) + goto next; } - } - /* - * Lets stop looking for an idle sibling when we reached - * the domain that spans the current cpu and prev_cpu. - */ - if (cpumask_test_cpu(cpu, sched_domain_span(sd)) && - cpumask_test_cpu(prev_cpu, sched_domain_span(sd))) - break; + target = cpumask_first_and(sched_group_cpus(sg), + tsk_cpus_allowed(p)); + goto done; +next: + sg = sg->next; + } while (sg != sd->groups); + } + if (!smt) { + smt = 1; + goto again; } +done: rcu_read_unlock(); return target; @@ -3511,7 +3604,7 @@ static bool update_sd_pick_busiest(struct sched_domain *sd, } /** - * update_sd_lb_stats - Update sched_group's statistics for load balancing. + * update_sd_lb_stats - Update sched_domain's statistics for load balancing. * @sd: sched_domain whose statistics are to be updated. * @this_cpu: Cpu for which load balance is currently performed. * @idle: Idle status of this_cpu diff --git a/kernel/sched_features.h b/kernel/sched_features.h index efa0a7b75dde..84802245abd2 100644 --- a/kernel/sched_features.h +++ b/kernel/sched_features.h @@ -67,3 +67,4 @@ SCHED_FEAT(NONTASK_POWER, 1) SCHED_FEAT(TTWU_QUEUE, 1) SCHED_FEAT(FORCE_SD_OVERLAP, 0) +SCHED_FEAT(RT_RUNTIME_SHARE, 1) diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c index 056cbd2e2a27..583a1368afe6 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched_rt.c @@ -560,6 +560,9 @@ static int balance_runtime(struct rt_rq *rt_rq) { int more = 0; + if (!sched_feat(RT_RUNTIME_SHARE)) + return more; + if (rt_rq->rt_time > rt_rq->rt_runtime) { raw_spin_unlock(&rt_rq->rt_runtime_lock); more = do_balance_runtime(rt_rq); diff --git a/kernel/signal.c b/kernel/signal.c index b3f78d09a105..206551563cce 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1994,8 +1994,6 @@ static bool do_signal_stop(int signr) */ if (!(sig->flags & SIGNAL_STOP_STOPPED)) sig->group_exit_code = signr; - else - WARN_ON_ONCE(!current->ptrace); sig->group_stop_count = 0; diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c index 6318b511afa1..a650694883a1 100644 --- a/kernel/sysctl_binary.c +++ b/kernel/sysctl_binary.c @@ -1354,7 +1354,7 @@ static ssize_t binary_sysctl(const int *name, int nlen, fput(file); out_putname: - putname(pathname); + __putname(pathname); out: return result; } diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index c436e790b21b..8a46f5d64504 100644 --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -195,7 +195,7 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer) struct alarm *alarm; ktime_t expired = next->expires; - if (expired.tv64 >= now.tv64) + if (expired.tv64 > now.tv64) break; alarm = container_of(next, struct alarm, node); diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index cf52fda2e096..d3ad022136e5 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -492,6 +492,22 @@ void clocksource_touch_watchdog(void) } /** + * clocksource_max_adjustment- Returns max adjustment amount + * @cs: Pointer to clocksource + * + */ +static u32 clocksource_max_adjustment(struct clocksource *cs) +{ + u64 ret; + /* + * We won't try to correct for more then 11% adjustments (110,000 ppm), + */ + ret = (u64)cs->mult * 11; + do_div(ret,100); + return (u32)ret; +} + +/** * clocksource_max_deferment - Returns max time the clocksource can be deferred * @cs: Pointer to clocksource * @@ -503,25 +519,28 @@ static u64 clocksource_max_deferment(struct clocksource *cs) /* * Calculate the maximum number of cycles that we can pass to the * cyc2ns function without overflowing a 64-bit signed result. The - * maximum number of cycles is equal to ULLONG_MAX/cs->mult which - * is equivalent to the below. - * max_cycles < (2^63)/cs->mult - * max_cycles < 2^(log2((2^63)/cs->mult)) - * max_cycles < 2^(log2(2^63) - log2(cs->mult)) - * max_cycles < 2^(63 - log2(cs->mult)) - * max_cycles < 1 << (63 - log2(cs->mult)) + * maximum number of cycles is equal to ULLONG_MAX/(cs->mult+cs->maxadj) + * which is equivalent to the below. + * max_cycles < (2^63)/(cs->mult + cs->maxadj) + * max_cycles < 2^(log2((2^63)/(cs->mult + cs->maxadj))) + * max_cycles < 2^(log2(2^63) - log2(cs->mult + cs->maxadj)) + * max_cycles < 2^(63 - log2(cs->mult + cs->maxadj)) + * max_cycles < 1 << (63 - log2(cs->mult + cs->maxadj)) * Please note that we add 1 to the result of the log2 to account for * any rounding errors, ensure the above inequality is satisfied and * no overflow will occur. */ - max_cycles = 1ULL << (63 - (ilog2(cs->mult) + 1)); + max_cycles = 1ULL << (63 - (ilog2(cs->mult + cs->maxadj) + 1)); /* * The actual maximum number of cycles we can defer the clocksource is * determined by the minimum of max_cycles and cs->mask. + * Note: Here we subtract the maxadj to make sure we don't sleep for + * too long if there's a large negative adjustment. */ max_cycles = min_t(u64, max_cycles, (u64) cs->mask); - max_nsecs = clocksource_cyc2ns(max_cycles, cs->mult, cs->shift); + max_nsecs = clocksource_cyc2ns(max_cycles, cs->mult - cs->maxadj, + cs->shift); /* * To ensure that the clocksource does not wrap whilst we are idle, @@ -529,7 +548,7 @@ static u64 clocksource_max_deferment(struct clocksource *cs) * note a margin of 12.5% is used because this can be computed with * a shift, versus say 10% which would require division. */ - return max_nsecs - (max_nsecs >> 5); + return max_nsecs - (max_nsecs >> 3); } #ifndef CONFIG_ARCH_USES_GETTIMEOFFSET @@ -628,7 +647,7 @@ static void clocksource_enqueue(struct clocksource *cs) /** * __clocksource_updatefreq_scale - Used update clocksource with new freq - * @t: clocksource to be registered + * @cs: clocksource to be registered * @scale: Scale factor multiplied against freq to get clocksource hz * @freq: clocksource frequency (cycles per second) divided by scale * @@ -640,7 +659,6 @@ static void clocksource_enqueue(struct clocksource *cs) void __clocksource_updatefreq_scale(struct clocksource *cs, u32 scale, u32 freq) { u64 sec; - /* * Calc the maximum number of seconds which we can run before * wrapping around. For clocksources which have a mask > 32bit @@ -651,7 +669,7 @@ void __clocksource_updatefreq_scale(struct clocksource *cs, u32 scale, u32 freq) * ~ 0.06ppm granularity for NTP. We apply the same 12.5% * margin as we do in clocksource_max_deferment() */ - sec = (cs->mask - (cs->mask >> 5)); + sec = (cs->mask - (cs->mask >> 3)); do_div(sec, freq); do_div(sec, scale); if (!sec) @@ -661,13 +679,27 @@ void __clocksource_updatefreq_scale(struct clocksource *cs, u32 scale, u32 freq) clocks_calc_mult_shift(&cs->mult, &cs->shift, freq, NSEC_PER_SEC / scale, sec * scale); + + /* + * for clocksources that have large mults, to avoid overflow. + * Since mult may be adjusted by ntp, add an safety extra margin + * + */ + cs->maxadj = clocksource_max_adjustment(cs); + while ((cs->mult + cs->maxadj < cs->mult) + || (cs->mult - cs->maxadj > cs->mult)) { + cs->mult >>= 1; + cs->shift--; + cs->maxadj = clocksource_max_adjustment(cs); + } + cs->max_idle_ns = clocksource_max_deferment(cs); } EXPORT_SYMBOL_GPL(__clocksource_updatefreq_scale); /** * __clocksource_register_scale - Used to install new clocksources - * @t: clocksource to be registered + * @cs: clocksource to be registered * @scale: Scale factor multiplied against freq to get clocksource hz * @freq: clocksource frequency (cycles per second) divided by scale * @@ -695,12 +727,18 @@ EXPORT_SYMBOL_GPL(__clocksource_register_scale); /** * clocksource_register - Used to install new clocksources - * @t: clocksource to be registered + * @cs: clocksource to be registered * * Returns -EBUSY if registration fails, zero otherwise. */ int clocksource_register(struct clocksource *cs) { + /* calculate max adjustment for given mult/shift */ + cs->maxadj = clocksource_max_adjustment(cs); + WARN_ONCE(cs->mult + cs->maxadj < cs->mult, + "Clocksource %s might overflow on 11%% adjustment\n", + cs->name); + /* calculate max idle time permitted for this clocksource */ cs->max_idle_ns = clocksource_max_deferment(cs); @@ -723,6 +761,8 @@ static void __clocksource_change_rating(struct clocksource *cs, int rating) /** * clocksource_change_rating - Change the rating of a registered clocksource + * @cs: clocksource to be changed + * @rating: new rating */ void clocksource_change_rating(struct clocksource *cs, int rating) { @@ -734,6 +774,7 @@ EXPORT_SYMBOL(clocksource_change_rating); /** * clocksource_unregister - remove a registered clocksource + * @cs: clocksource to be unregistered */ void clocksource_unregister(struct clocksource *cs) { @@ -749,6 +790,7 @@ EXPORT_SYMBOL(clocksource_unregister); /** * sysfs_show_current_clocksources - sysfs interface for current clocksource * @dev: unused + * @attr: unused * @buf: char buffer to be filled with clocksource list * * Provides sysfs interface for listing current clocksource. @@ -769,6 +811,7 @@ sysfs_show_current_clocksources(struct sys_device *dev, /** * sysfs_override_clocksource - interface for manually overriding clocksource * @dev: unused + * @attr: unused * @buf: name of override clocksource * @count: length of buffer * @@ -804,6 +847,7 @@ static ssize_t sysfs_override_clocksource(struct sys_device *dev, /** * sysfs_show_available_clocksources - sysfs interface for listing clocksource * @dev: unused + * @attr: unused * @buf: char buffer to be filled with clocksource list * * Provides sysfs interface for listing registered clocksources diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index f954282d9a82..fd4a7b1625a2 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -71,7 +71,7 @@ int tick_check_broadcast_device(struct clock_event_device *dev) (dev->features & CLOCK_EVT_FEAT_C3STOP)) return 0; - clockevents_exchange_device(NULL, dev); + clockevents_exchange_device(tick_broadcast_device.evtdev, dev); tick_broadcast_device.evtdev = dev; if (!cpumask_empty(tick_get_broadcast_mask())) tick_broadcast_start_periodic(dev); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 2b021b0e8507..237841378c03 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -249,6 +249,8 @@ ktime_t ktime_get(void) secs = xtime.tv_sec + wall_to_monotonic.tv_sec; nsecs = xtime.tv_nsec + wall_to_monotonic.tv_nsec; nsecs += timekeeping_get_ns(); + /* If arch requires, add in gettimeoffset() */ + nsecs += arch_gettimeoffset(); } while (read_seqretry(&xtime_lock, seq)); /* @@ -280,6 +282,8 @@ void ktime_get_ts(struct timespec *ts) *ts = xtime; tomono = wall_to_monotonic; nsecs = timekeeping_get_ns(); + /* If arch requires, add in gettimeoffset() */ + nsecs += arch_gettimeoffset(); } while (read_seqretry(&xtime_lock, seq)); @@ -802,14 +806,44 @@ static void timekeeping_adjust(s64 offset) s64 error, interval = timekeeper.cycle_interval; int adj; + /* + * The point of this is to check if the error is greater then half + * an interval. + * + * First we shift it down from NTP_SHIFT to clocksource->shifted nsecs. + * + * Note we subtract one in the shift, so that error is really error*2. + * This "saves" dividing(shifting) intererval twice, but keeps the + * (error > interval) comparision as still measuring if error is + * larger then half an interval. + * + * Note: It does not "save" on aggrivation when reading the code. + */ error = timekeeper.ntp_error >> (timekeeper.ntp_error_shift - 1); if (error > interval) { + /* + * We now divide error by 4(via shift), which checks if + * the error is greater then twice the interval. + * If it is greater, we need a bigadjust, if its smaller, + * we can adjust by 1. + */ error >>= 2; + /* + * XXX - In update_wall_time, we round up to the next + * nanosecond, and store the amount rounded up into + * the error. This causes the likely below to be unlikely. + * + * The properfix is to avoid rounding up by using + * the high precision timekeeper.xtime_nsec instead of + * xtime.tv_nsec everywhere. Fixing this will take some + * time. + */ if (likely(error <= interval)) adj = 1; else adj = timekeeping_bigadjust(error, &interval, &offset); } else if (error < -interval) { + /* See comment above, this is just switched for the negative */ error >>= 2; if (likely(error >= -interval)) { adj = -1; @@ -817,9 +851,65 @@ static void timekeeping_adjust(s64 offset) offset = -offset; } else adj = timekeeping_bigadjust(error, &interval, &offset); - } else + } else /* No adjustment needed */ return; + WARN_ONCE(timekeeper.clock->maxadj && + (timekeeper.mult + adj > timekeeper.clock->mult + + timekeeper.clock->maxadj), + "Adjusting %s more then 11%% (%ld vs %ld)\n", + timekeeper.clock->name, (long)timekeeper.mult + adj, + (long)timekeeper.clock->mult + + timekeeper.clock->maxadj); + /* + * So the following can be confusing. + * + * To keep things simple, lets assume adj == 1 for now. + * + * When adj != 1, remember that the interval and offset values + * have been appropriately scaled so the math is the same. + * + * The basic idea here is that we're increasing the multiplier + * by one, this causes the xtime_interval to be incremented by + * one cycle_interval. This is because: + * xtime_interval = cycle_interval * mult + * So if mult is being incremented by one: + * xtime_interval = cycle_interval * (mult + 1) + * Its the same as: + * xtime_interval = (cycle_interval * mult) + cycle_interval + * Which can be shortened to: + * xtime_interval += cycle_interval + * + * So offset stores the non-accumulated cycles. Thus the current + * time (in shifted nanoseconds) is: + * now = (offset * adj) + xtime_nsec + * Now, even though we're adjusting the clock frequency, we have + * to keep time consistent. In other words, we can't jump back + * in time, and we also want to avoid jumping forward in time. + * + * So given the same offset value, we need the time to be the same + * both before and after the freq adjustment. + * now = (offset * adj_1) + xtime_nsec_1 + * now = (offset * adj_2) + xtime_nsec_2 + * So: + * (offset * adj_1) + xtime_nsec_1 = + * (offset * adj_2) + xtime_nsec_2 + * And we know: + * adj_2 = adj_1 + 1 + * So: + * (offset * adj_1) + xtime_nsec_1 = + * (offset * (adj_1+1)) + xtime_nsec_2 + * (offset * adj_1) + xtime_nsec_1 = + * (offset * adj_1) + offset + xtime_nsec_2 + * Canceling the sides: + * xtime_nsec_1 = offset + xtime_nsec_2 + * Which gives us: + * xtime_nsec_2 = xtime_nsec_1 - offset + * Which simplfies to: + * xtime_nsec -= offset + * + * XXX - TODO: Doc ntp_error calculation. + */ timekeeper.mult += adj; timekeeper.xtime_interval += interval; timekeeper.xtime_nsec -= offset; diff --git a/kernel/timer.c b/kernel/timer.c index dbaa62422b13..a297ffcf888e 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -427,6 +427,12 @@ static int timer_fixup_init(void *addr, enum debug_obj_state state) } } +/* Stub timer callback for improperly used timers. */ +static void stub_timer(unsigned long data) +{ + WARN_ON(1); +} + /* * fixup_activate is called when: * - an active object is activated @@ -450,7 +456,8 @@ static int timer_fixup_activate(void *addr, enum debug_obj_state state) debug_object_activate(timer, &timer_debug_descr); return 0; } else { - WARN_ON_ONCE(1); + setup_timer(timer, stub_timer, 0); + return 1; } return 0; @@ -480,12 +487,40 @@ static int timer_fixup_free(void *addr, enum debug_obj_state state) } } +/* + * fixup_assert_init is called when: + * - an untracked/uninit-ed object is found + */ +static int timer_fixup_assert_init(void *addr, enum debug_obj_state state) +{ + struct timer_list *timer = addr; + + switch (state) { + case ODEBUG_STATE_NOTAVAILABLE: + if (timer->entry.prev == TIMER_ENTRY_STATIC) { + /* + * This is not really a fixup. The timer was + * statically initialized. We just make sure that it + * is tracked in the object tracker. + */ + debug_object_init(timer, &timer_debug_descr); + return 0; + } else { + setup_timer(timer, stub_timer, 0); + return 1; + } + default: + return 0; + } +} + static struct debug_obj_descr timer_debug_descr = { - .name = "timer_list", - .debug_hint = timer_debug_hint, - .fixup_init = timer_fixup_init, - .fixup_activate = timer_fixup_activate, - .fixup_free = timer_fixup_free, + .name = "timer_list", + .debug_hint = timer_debug_hint, + .fixup_init = timer_fixup_init, + .fixup_activate = timer_fixup_activate, + .fixup_free = timer_fixup_free, + .fixup_assert_init = timer_fixup_assert_init, }; static inline void debug_timer_init(struct timer_list *timer) @@ -508,6 +543,11 @@ static inline void debug_timer_free(struct timer_list *timer) debug_object_free(timer, &timer_debug_descr); } +static inline void debug_timer_assert_init(struct timer_list *timer) +{ + debug_object_assert_init(timer, &timer_debug_descr); +} + static void __init_timer(struct timer_list *timer, const char *name, struct lock_class_key *key); @@ -531,6 +571,7 @@ EXPORT_SYMBOL_GPL(destroy_timer_on_stack); static inline void debug_timer_init(struct timer_list *timer) { } static inline void debug_timer_activate(struct timer_list *timer) { } static inline void debug_timer_deactivate(struct timer_list *timer) { } +static inline void debug_timer_assert_init(struct timer_list *timer) { } #endif static inline void debug_init(struct timer_list *timer) @@ -552,6 +593,11 @@ static inline void debug_deactivate(struct timer_list *timer) trace_timer_cancel(timer); } +static inline void debug_assert_init(struct timer_list *timer) +{ + debug_timer_assert_init(timer); +} + static void __init_timer(struct timer_list *timer, const char *name, struct lock_class_key *key) @@ -902,6 +948,8 @@ int del_timer(struct timer_list *timer) unsigned long flags; int ret = 0; + debug_assert_init(timer); + timer_stats_timer_clear_start_info(timer); if (timer_pending(timer)) { base = lock_timer_base(timer, &flags); @@ -932,6 +980,8 @@ int try_to_del_timer_sync(struct timer_list *timer) unsigned long flags; int ret = -1; + debug_assert_init(timer); + base = lock_timer_base(timer, &flags); if (base->running_timer == timer) @@ -1368,7 +1418,7 @@ SYSCALL_DEFINE0(getppid) int pid; rcu_read_lock(); - pid = task_tgid_vnr(current->real_parent); + pid = task_tgid_vnr(rcu_dereference(current->real_parent)); rcu_read_unlock(); return pid; diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 900b409543db..b1e8943fed1d 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -152,7 +152,6 @@ void clear_ftrace_function(void) ftrace_pid_function = ftrace_stub; } -#undef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST #ifndef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST /* * For those archs that do not test ftrace_trace_stop in their @@ -1212,7 +1211,9 @@ ftrace_hash_move(struct ftrace_ops *ops, int enable, if (!src->count) { free_ftrace_hash_rcu(*dst); rcu_assign_pointer(*dst, EMPTY_HASH); - return 0; + /* still need to update the function records */ + ret = 0; + goto out; } /* diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 581876f9f387..c212a7f934ec 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -1078,7 +1078,6 @@ event_subsystem_dir(const char *name, struct dentry *d_events) /* First see if we did not already create this dir */ list_for_each_entry(system, &event_subsystems, list) { if (strcmp(system->name, name) == 0) { - __get_system(system); system->nr_events++; return system->entry; } diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 816d3d074979..95dc31efd6dd 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -1649,7 +1649,9 @@ static int replace_system_preds(struct event_subsystem *system, */ err = replace_preds(call, NULL, ps, filter_string, true); if (err) - goto fail; + call->flags |= TRACE_EVENT_FL_NO_SET_FILTER; + else + call->flags &= ~TRACE_EVENT_FL_NO_SET_FILTER; } list_for_each_entry(call, &ftrace_events, list) { @@ -1658,6 +1660,9 @@ static int replace_system_preds(struct event_subsystem *system, if (strcmp(call->class->system, system->name) != 0) continue; + if (call->flags & TRACE_EVENT_FL_NO_SET_FILTER) + continue; + filter_item = kzalloc(sizeof(*filter_item), GFP_KERNEL); if (!filter_item) goto fail_mem; @@ -1686,7 +1691,7 @@ static int replace_system_preds(struct event_subsystem *system, * replace the filter for the call. */ filter = call->filter; - call->filter = filter_item->filter; + rcu_assign_pointer(call->filter, filter_item->filter); filter_item->filter = filter; fail = false; @@ -1741,7 +1746,7 @@ int apply_event_filter(struct ftrace_event_call *call, char *filter_string) filter = call->filter; if (!filter) goto out_unlock; - call->filter = NULL; + RCU_INIT_POINTER(call->filter, NULL); /* Make sure the filter is not being used */ synchronize_sched(); __free_filter(filter); @@ -1782,7 +1787,7 @@ out: * string */ tmp = call->filter; - call->filter = filter; + rcu_assign_pointer(call->filter, filter); if (tmp) { /* Make sure the call is done with the filter */ synchronize_sched(); diff --git a/kernel/wait.c b/kernel/wait.c index 26fa7797f90f..7fdd9eaca2c3 100644 --- a/kernel/wait.c +++ b/kernel/wait.c @@ -10,10 +10,10 @@ #include <linux/wait.h> #include <linux/hash.h> -void __init_waitqueue_head(wait_queue_head_t *q, struct lock_class_key *key) +void __init_waitqueue_head(wait_queue_head_t *q, const char *name, struct lock_class_key *key) { spin_lock_init(&q->lock); - lockdep_set_class(&q->lock, key); + lockdep_set_class_and_name(&q->lock, key, name); INIT_LIST_HEAD(&q->task_list); } |