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authorDave Airlie <airlied@redhat.com>2015-04-20 11:32:26 +1000
committerDave Airlie <airlied@redhat.com>2015-04-20 13:05:20 +1000
commit2c33ce009ca2389dbf0535d0672214d09738e35e (patch)
tree6186a6458c3c160385d794a23eaf07c786a9e61b /kernel/events/core.c
parentcec32a47010647e8b0603726ebb75b990a4057a4 (diff)
parent09d51602cf84a1264946711dd4ea0dddbac599a1 (diff)
Merge Linus master into drm-next
The merge is clean, but the arm build fails afterwards, due to API changes in the regulator tree. I've included the patch into the merge to fix the build. Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'kernel/events/core.c')
-rw-r--r--kernel/events/core.c752
1 files changed, 587 insertions, 165 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 2fabc0627165..81aa3a4ece9f 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -34,14 +34,16 @@
#include <linux/syscalls.h>
#include <linux/anon_inodes.h>
#include <linux/kernel_stat.h>
+#include <linux/cgroup.h>
#include <linux/perf_event.h>
#include <linux/ftrace_event.h>
#include <linux/hw_breakpoint.h>
#include <linux/mm_types.h>
-#include <linux/cgroup.h>
#include <linux/module.h>
#include <linux/mman.h>
#include <linux/compat.h>
+#include <linux/bpf.h>
+#include <linux/filter.h>
#include "internal.h"
@@ -153,7 +155,7 @@ enum event_type_t {
*/
struct static_key_deferred perf_sched_events __read_mostly;
static DEFINE_PER_CPU(atomic_t, perf_cgroup_events);
-static DEFINE_PER_CPU(atomic_t, perf_branch_stack_events);
+static DEFINE_PER_CPU(int, perf_sched_cb_usages);
static atomic_t nr_mmap_events __read_mostly;
static atomic_t nr_comm_events __read_mostly;
@@ -327,6 +329,11 @@ static inline u64 perf_clock(void)
return local_clock();
}
+static inline u64 perf_event_clock(struct perf_event *event)
+{
+ return event->clock();
+}
+
static inline struct perf_cpu_context *
__get_cpu_context(struct perf_event_context *ctx)
{
@@ -351,32 +358,6 @@ static void perf_ctx_unlock(struct perf_cpu_context *cpuctx,
#ifdef CONFIG_CGROUP_PERF
-/*
- * perf_cgroup_info keeps track of time_enabled for a cgroup.
- * This is a per-cpu dynamically allocated data structure.
- */
-struct perf_cgroup_info {
- u64 time;
- u64 timestamp;
-};
-
-struct perf_cgroup {
- struct cgroup_subsys_state css;
- struct perf_cgroup_info __percpu *info;
-};
-
-/*
- * Must ensure cgroup is pinned (css_get) before calling
- * this function. In other words, we cannot call this function
- * if there is no cgroup event for the current CPU context.
- */
-static inline struct perf_cgroup *
-perf_cgroup_from_task(struct task_struct *task)
-{
- return container_of(task_css(task, perf_event_cgrp_id),
- struct perf_cgroup, css);
-}
-
static inline bool
perf_cgroup_match(struct perf_event *event)
{
@@ -905,6 +886,15 @@ static void get_ctx(struct perf_event_context *ctx)
WARN_ON(!atomic_inc_not_zero(&ctx->refcount));
}
+static void free_ctx(struct rcu_head *head)
+{
+ struct perf_event_context *ctx;
+
+ ctx = container_of(head, struct perf_event_context, rcu_head);
+ kfree(ctx->task_ctx_data);
+ kfree(ctx);
+}
+
static void put_ctx(struct perf_event_context *ctx)
{
if (atomic_dec_and_test(&ctx->refcount)) {
@@ -912,7 +902,7 @@ static void put_ctx(struct perf_event_context *ctx)
put_ctx(ctx->parent_ctx);
if (ctx->task)
put_task_struct(ctx->task);
- kfree_rcu(ctx, rcu_head);
+ call_rcu(&ctx->rcu_head, free_ctx);
}
}
@@ -1239,9 +1229,6 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx)
if (is_cgroup_event(event))
ctx->nr_cgroups++;
- if (has_branch_stack(event))
- ctx->nr_branch_stack++;
-
list_add_rcu(&event->event_entry, &ctx->event_list);
ctx->nr_events++;
if (event->attr.inherit_stat)
@@ -1408,9 +1395,6 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx)
cpuctx->cgrp = NULL;
}
- if (has_branch_stack(event))
- ctx->nr_branch_stack--;
-
ctx->nr_events--;
if (event->attr.inherit_stat)
ctx->nr_stat--;
@@ -1847,6 +1831,7 @@ static void perf_set_shadow_time(struct perf_event *event,
#define MAX_INTERRUPTS (~0ULL)
static void perf_log_throttle(struct perf_event *event, int enable);
+static void perf_log_itrace_start(struct perf_event *event);
static int
event_sched_in(struct perf_event *event,
@@ -1881,6 +1866,12 @@ event_sched_in(struct perf_event *event,
perf_pmu_disable(event->pmu);
+ event->tstamp_running += tstamp - event->tstamp_stopped;
+
+ perf_set_shadow_time(event, ctx, tstamp);
+
+ perf_log_itrace_start(event);
+
if (event->pmu->add(event, PERF_EF_START)) {
event->state = PERF_EVENT_STATE_INACTIVE;
event->oncpu = -1;
@@ -1888,10 +1879,6 @@ event_sched_in(struct perf_event *event,
goto out;
}
- event->tstamp_running += tstamp - event->tstamp_stopped;
-
- perf_set_shadow_time(event, ctx, tstamp);
-
if (!is_software_event(event))
cpuctx->active_oncpu++;
if (!ctx->nr_active++)
@@ -2559,6 +2546,9 @@ static void perf_event_context_sched_out(struct task_struct *task, int ctxn,
next->perf_event_ctxp[ctxn] = ctx;
ctx->task = next;
next_ctx->task = task;
+
+ swap(ctx->task_ctx_data, next_ctx->task_ctx_data);
+
do_switch = 0;
perf_event_sync_stat(ctx, next_ctx);
@@ -2577,6 +2567,56 @@ unlock:
}
}
+void perf_sched_cb_dec(struct pmu *pmu)
+{
+ this_cpu_dec(perf_sched_cb_usages);
+}
+
+void perf_sched_cb_inc(struct pmu *pmu)
+{
+ this_cpu_inc(perf_sched_cb_usages);
+}
+
+/*
+ * This function provides the context switch callback to the lower code
+ * layer. It is invoked ONLY when the context switch callback is enabled.
+ */
+static void perf_pmu_sched_task(struct task_struct *prev,
+ struct task_struct *next,
+ bool sched_in)
+{
+ struct perf_cpu_context *cpuctx;
+ struct pmu *pmu;
+ unsigned long flags;
+
+ if (prev == next)
+ return;
+
+ local_irq_save(flags);
+
+ rcu_read_lock();
+
+ list_for_each_entry_rcu(pmu, &pmus, entry) {
+ if (pmu->sched_task) {
+ cpuctx = this_cpu_ptr(pmu->pmu_cpu_context);
+
+ perf_ctx_lock(cpuctx, cpuctx->task_ctx);
+
+ perf_pmu_disable(pmu);
+
+ pmu->sched_task(cpuctx->task_ctx, sched_in);
+
+ perf_pmu_enable(pmu);
+
+ perf_ctx_unlock(cpuctx, cpuctx->task_ctx);
+ }
+ }
+
+ rcu_read_unlock();
+
+ local_irq_restore(flags);
+}
+
#define for_each_task_context_nr(ctxn) \
for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++)
@@ -2596,6 +2636,9 @@ void __perf_event_task_sched_out(struct task_struct *task,
{
int ctxn;
+ if (__this_cpu_read(perf_sched_cb_usages))
+ perf_pmu_sched_task(task, next, false);
+
for_each_task_context_nr(ctxn)
perf_event_context_sched_out(task, ctxn, next);
@@ -2755,64 +2798,6 @@ static void perf_event_context_sched_in(struct perf_event_context *ctx,
}
/*
- * When sampling the branck stack in system-wide, it may be necessary
- * to flush the stack on context switch. This happens when the branch
- * stack does not tag its entries with the pid of the current task.
- * Otherwise it becomes impossible to associate a branch entry with a
- * task. This ambiguity is more likely to appear when the branch stack
- * supports priv level filtering and the user sets it to monitor only
- * at the user level (which could be a useful measurement in system-wide
- * mode). In that case, the risk is high of having a branch stack with
- * branch from multiple tasks. Flushing may mean dropping the existing
- * entries or stashing them somewhere in the PMU specific code layer.
- *
- * This function provides the context switch callback to the lower code
- * layer. It is invoked ONLY when there is at least one system-wide context
- * with at least one active event using taken branch sampling.
- */
-static void perf_branch_stack_sched_in(struct task_struct *prev,
- struct task_struct *task)
-{
- struct perf_cpu_context *cpuctx;
- struct pmu *pmu;
- unsigned long flags;
-
- /* no need to flush branch stack if not changing task */
- if (prev == task)
- return;
-
- local_irq_save(flags);
-
- rcu_read_lock();
-
- list_for_each_entry_rcu(pmu, &pmus, entry) {
- cpuctx = this_cpu_ptr(pmu->pmu_cpu_context);
-
- /*
- * check if the context has at least one
- * event using PERF_SAMPLE_BRANCH_STACK
- */
- if (cpuctx->ctx.nr_branch_stack > 0
- && pmu->flush_branch_stack) {
-
- perf_ctx_lock(cpuctx, cpuctx->task_ctx);
-
- perf_pmu_disable(pmu);
-
- pmu->flush_branch_stack();
-
- perf_pmu_enable(pmu);
-
- perf_ctx_unlock(cpuctx, cpuctx->task_ctx);
- }
- }
-
- rcu_read_unlock();
-
- local_irq_restore(flags);
-}
-
-/*
* Called from scheduler to add the events of the current task
* with interrupts disabled.
*
@@ -2844,9 +2829,8 @@ void __perf_event_task_sched_in(struct task_struct *prev,
if (atomic_read(this_cpu_ptr(&perf_cgroup_events)))
perf_cgroup_sched_in(prev, task);
- /* check for system-wide branch_stack events */
- if (atomic_read(this_cpu_ptr(&perf_branch_stack_events)))
- perf_branch_stack_sched_in(prev, task);
+ if (__this_cpu_read(perf_sched_cb_usages))
+ perf_pmu_sched_task(prev, task, true);
}
static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count)
@@ -3220,7 +3204,10 @@ static void __perf_event_read(void *info)
static inline u64 perf_event_count(struct perf_event *event)
{
- return local64_read(&event->count) + atomic64_read(&event->child_count);
+ if (event->pmu->count)
+ return event->pmu->count(event);
+
+ return __perf_event_count(event);
}
static u64 perf_event_read(struct perf_event *event)
@@ -3321,12 +3308,15 @@ errout:
* Returns a matching context with refcount and pincount.
*/
static struct perf_event_context *
-find_get_context(struct pmu *pmu, struct task_struct *task, int cpu)
+find_get_context(struct pmu *pmu, struct task_struct *task,
+ struct perf_event *event)
{
struct perf_event_context *ctx, *clone_ctx = NULL;
struct perf_cpu_context *cpuctx;
+ void *task_ctx_data = NULL;
unsigned long flags;
int ctxn, err;
+ int cpu = event->cpu;
if (!task) {
/* Must be root to operate on a CPU event: */
@@ -3354,11 +3344,24 @@ find_get_context(struct pmu *pmu, struct task_struct *task, int cpu)
if (ctxn < 0)
goto errout;
+ if (event->attach_state & PERF_ATTACH_TASK_DATA) {
+ task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL);
+ if (!task_ctx_data) {
+ err = -ENOMEM;
+ goto errout;
+ }
+ }
+
retry:
ctx = perf_lock_task_context(task, ctxn, &flags);
if (ctx) {
clone_ctx = unclone_ctx(ctx);
++ctx->pin_count;
+
+ if (task_ctx_data && !ctx->task_ctx_data) {
+ ctx->task_ctx_data = task_ctx_data;
+ task_ctx_data = NULL;
+ }
raw_spin_unlock_irqrestore(&ctx->lock, flags);
if (clone_ctx)
@@ -3369,6 +3372,11 @@ retry:
if (!ctx)
goto errout;
+ if (task_ctx_data) {
+ ctx->task_ctx_data = task_ctx_data;
+ task_ctx_data = NULL;
+ }
+
err = 0;
mutex_lock(&task->perf_event_mutex);
/*
@@ -3395,13 +3403,16 @@ retry:
}
}
+ kfree(task_ctx_data);
return ctx;
errout:
+ kfree(task_ctx_data);
return ERR_PTR(err);
}
static void perf_event_free_filter(struct perf_event *event);
+static void perf_event_free_bpf_prog(struct perf_event *event);
static void free_event_rcu(struct rcu_head *head)
{
@@ -3411,10 +3422,10 @@ static void free_event_rcu(struct rcu_head *head)
if (event->ns)
put_pid_ns(event->ns);
perf_event_free_filter(event);
+ perf_event_free_bpf_prog(event);
kfree(event);
}
-static void ring_buffer_put(struct ring_buffer *rb);
static void ring_buffer_attach(struct perf_event *event,
struct ring_buffer *rb);
@@ -3423,10 +3434,6 @@ static void unaccount_event_cpu(struct perf_event *event, int cpu)
if (event->parent)
return;
- if (has_branch_stack(event)) {
- if (!(event->attach_state & PERF_ATTACH_TASK))
- atomic_dec(&per_cpu(perf_branch_stack_events, cpu));
- }
if (is_cgroup_event(event))
atomic_dec(&per_cpu(perf_cgroup_events, cpu));
}
@@ -3454,6 +3461,91 @@ static void unaccount_event(struct perf_event *event)
unaccount_event_cpu(event, event->cpu);
}
+/*
+ * The following implement mutual exclusion of events on "exclusive" pmus
+ * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled
+ * at a time, so we disallow creating events that might conflict, namely:
+ *
+ * 1) cpu-wide events in the presence of per-task events,
+ * 2) per-task events in the presence of cpu-wide events,
+ * 3) two matching events on the same context.
+ *
+ * The former two cases are handled in the allocation path (perf_event_alloc(),
+ * __free_event()), the latter -- before the first perf_install_in_context().
+ */
+static int exclusive_event_init(struct perf_event *event)
+{
+ struct pmu *pmu = event->pmu;
+
+ if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE))
+ return 0;
+
+ /*
+ * Prevent co-existence of per-task and cpu-wide events on the
+ * same exclusive pmu.
+ *
+ * Negative pmu::exclusive_cnt means there are cpu-wide
+ * events on this "exclusive" pmu, positive means there are
+ * per-task events.
+ *
+ * Since this is called in perf_event_alloc() path, event::ctx
+ * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK
+ * to mean "per-task event", because unlike other attach states it
+ * never gets cleared.
+ */
+ if (event->attach_state & PERF_ATTACH_TASK) {
+ if (!atomic_inc_unless_negative(&pmu->exclusive_cnt))
+ return -EBUSY;
+ } else {
+ if (!atomic_dec_unless_positive(&pmu->exclusive_cnt))
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
+static void exclusive_event_destroy(struct perf_event *event)
+{
+ struct pmu *pmu = event->pmu;
+
+ if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE))
+ return;
+
+ /* see comment in exclusive_event_init() */
+ if (event->attach_state & PERF_ATTACH_TASK)
+ atomic_dec(&pmu->exclusive_cnt);
+ else
+ atomic_inc(&pmu->exclusive_cnt);
+}
+
+static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2)
+{
+ if ((e1->pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) &&
+ (e1->cpu == e2->cpu ||
+ e1->cpu == -1 ||
+ e2->cpu == -1))
+ return true;
+ return false;
+}
+
+/* Called under the same ctx::mutex as perf_install_in_context() */
+static bool exclusive_event_installable(struct perf_event *event,
+ struct perf_event_context *ctx)
+{
+ struct perf_event *iter_event;
+ struct pmu *pmu = event->pmu;
+
+ if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE))
+ return true;
+
+ list_for_each_entry(iter_event, &ctx->event_list, event_entry) {
+ if (exclusive_event_match(iter_event, event))
+ return false;
+ }
+
+ return true;
+}
+
static void __free_event(struct perf_event *event)
{
if (!event->parent) {
@@ -3467,8 +3559,10 @@ static void __free_event(struct perf_event *event)
if (event->ctx)
put_ctx(event->ctx);
- if (event->pmu)
+ if (event->pmu) {
+ exclusive_event_destroy(event);
module_put(event->pmu->module);
+ }
call_rcu(&event->rcu_head, free_event_rcu);
}
@@ -3927,6 +4021,7 @@ static inline int perf_fget_light(int fd, struct fd *p)
static int perf_event_set_output(struct perf_event *event,
struct perf_event *output_event);
static int perf_event_set_filter(struct perf_event *event, void __user *arg);
+static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd);
static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg)
{
@@ -3980,6 +4075,9 @@ static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned lon
case PERF_EVENT_IOC_SET_FILTER:
return perf_event_set_filter(event, (void __user *)arg);
+ case PERF_EVENT_IOC_SET_BPF:
+ return perf_event_set_bpf_prog(event, arg);
+
default:
return -ENOTTY;
}
@@ -4096,6 +4194,8 @@ static void perf_event_init_userpage(struct perf_event *event)
/* Allow new userspace to detect that bit 0 is deprecated */
userpg->cap_bit0_is_deprecated = 1;
userpg->size = offsetof(struct perf_event_mmap_page, __reserved);
+ userpg->data_offset = PAGE_SIZE;
+ userpg->data_size = perf_data_size(rb);
unlock:
rcu_read_unlock();
@@ -4263,7 +4363,7 @@ static void rb_free_rcu(struct rcu_head *rcu_head)
rb_free(rb);
}
-static struct ring_buffer *ring_buffer_get(struct perf_event *event)
+struct ring_buffer *ring_buffer_get(struct perf_event *event)
{
struct ring_buffer *rb;
@@ -4278,7 +4378,7 @@ static struct ring_buffer *ring_buffer_get(struct perf_event *event)
return rb;
}
-static void ring_buffer_put(struct ring_buffer *rb)
+void ring_buffer_put(struct ring_buffer *rb)
{
if (!atomic_dec_and_test(&rb->refcount))
return;
@@ -4295,6 +4395,9 @@ static void perf_mmap_open(struct vm_area_struct *vma)
atomic_inc(&event->mmap_count);
atomic_inc(&event->rb->mmap_count);
+ if (vma->vm_pgoff)
+ atomic_inc(&event->rb->aux_mmap_count);
+
if (event->pmu->event_mapped)
event->pmu->event_mapped(event);
}
@@ -4319,6 +4422,20 @@ static void perf_mmap_close(struct vm_area_struct *vma)
if (event->pmu->event_unmapped)
event->pmu->event_unmapped(event);
+ /*
+ * rb->aux_mmap_count will always drop before rb->mmap_count and
+ * event->mmap_count, so it is ok to use event->mmap_mutex to
+ * serialize with perf_mmap here.
+ */
+ if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff &&
+ atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) {
+ atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm);
+ vma->vm_mm->pinned_vm -= rb->aux_mmap_locked;
+
+ rb_free_aux(rb);
+ mutex_unlock(&event->mmap_mutex);
+ }
+
atomic_dec(&rb->mmap_count);
if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex))
@@ -4392,7 +4509,7 @@ out_put:
static const struct vm_operations_struct perf_mmap_vmops = {
.open = perf_mmap_open,
- .close = perf_mmap_close,
+ .close = perf_mmap_close, /* non mergable */
.fault = perf_mmap_fault,
.page_mkwrite = perf_mmap_fault,
};
@@ -4403,10 +4520,10 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
unsigned long user_locked, user_lock_limit;
struct user_struct *user = current_user();
unsigned long locked, lock_limit;
- struct ring_buffer *rb;
+ struct ring_buffer *rb = NULL;
unsigned long vma_size;
unsigned long nr_pages;
- long user_extra, extra;
+ long user_extra = 0, extra = 0;
int ret = 0, flags = 0;
/*
@@ -4421,7 +4538,66 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
return -EINVAL;
vma_size = vma->vm_end - vma->vm_start;
- nr_pages = (vma_size / PAGE_SIZE) - 1;
+
+ if (vma->vm_pgoff == 0) {
+ nr_pages = (vma_size / PAGE_SIZE) - 1;
+ } else {
+ /*
+ * AUX area mapping: if rb->aux_nr_pages != 0, it's already
+ * mapped, all subsequent mappings should have the same size
+ * and offset. Must be above the normal perf buffer.
+ */
+ u64 aux_offset, aux_size;
+
+ if (!event->rb)
+ return -EINVAL;
+
+ nr_pages = vma_size / PAGE_SIZE;
+
+ mutex_lock(&event->mmap_mutex);
+ ret = -EINVAL;
+
+ rb = event->rb;
+ if (!rb)
+ goto aux_unlock;
+
+ aux_offset = ACCESS_ONCE(rb->user_page->aux_offset);
+ aux_size = ACCESS_ONCE(rb->user_page->aux_size);
+
+ if (aux_offset < perf_data_size(rb) + PAGE_SIZE)
+ goto aux_unlock;
+
+ if (aux_offset != vma->vm_pgoff << PAGE_SHIFT)
+ goto aux_unlock;
+
+ /* already mapped with a different offset */
+ if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff)
+ goto aux_unlock;
+
+ if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE)
+ goto aux_unlock;
+
+ /* already mapped with a different size */
+ if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages)
+ goto aux_unlock;
+
+ if (!is_power_of_2(nr_pages))
+ goto aux_unlock;
+
+ if (!atomic_inc_not_zero(&rb->mmap_count))
+ goto aux_unlock;
+
+ if (rb_has_aux(rb)) {
+ atomic_inc(&rb->aux_mmap_count);
+ ret = 0;
+ goto unlock;
+ }
+
+ atomic_set(&rb->aux_mmap_count, 1);
+ user_extra = nr_pages;
+
+ goto accounting;
+ }
/*
* If we have rb pages ensure they're a power-of-two number, so we
@@ -4433,9 +4609,6 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
if (vma_size != PAGE_SIZE * (1 + nr_pages))
return -EINVAL;
- if (vma->vm_pgoff != 0)
- return -EINVAL;
-
WARN_ON_ONCE(event->ctx->parent_ctx);
again:
mutex_lock(&event->mmap_mutex);
@@ -4459,6 +4632,8 @@ again:
}
user_extra = nr_pages + 1;
+
+accounting:
user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10);
/*
@@ -4468,7 +4643,6 @@ again:
user_locked = atomic_long_read(&user->locked_vm) + user_extra;
- extra = 0;
if (user_locked > user_lock_limit)
extra = user_locked - user_lock_limit;
@@ -4482,35 +4656,46 @@ again:
goto unlock;
}
- WARN_ON(event->rb);
+ WARN_ON(!rb && event->rb);
if (vma->vm_flags & VM_WRITE)
flags |= RING_BUFFER_WRITABLE;
- rb = rb_alloc(nr_pages,
- event->attr.watermark ? event->attr.wakeup_watermark : 0,
- event->cpu, flags);
-
if (!rb) {
- ret = -ENOMEM;
- goto unlock;
- }
+ rb = rb_alloc(nr_pages,
+ event->attr.watermark ? event->attr.wakeup_watermark : 0,
+ event->cpu, flags);
- atomic_set(&rb->mmap_count, 1);
- rb->mmap_locked = extra;
- rb->mmap_user = get_current_user();
+ if (!rb) {
+ ret = -ENOMEM;
+ goto unlock;
+ }
- atomic_long_add(user_extra, &user->locked_vm);
- vma->vm_mm->pinned_vm += extra;
+ atomic_set(&rb->mmap_count, 1);
+ rb->mmap_user = get_current_user();
+ rb->mmap_locked = extra;
- ring_buffer_attach(event, rb);
+ ring_buffer_attach(event, rb);
- perf_event_init_userpage(event);
- perf_event_update_userpage(event);
+ perf_event_init_userpage(event);
+ perf_event_update_userpage(event);
+ } else {
+ ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages,
+ event->attr.aux_watermark, flags);
+ if (!ret)
+ rb->aux_mmap_locked = extra;
+ }
unlock:
- if (!ret)
+ if (!ret) {
+ atomic_long_add(user_extra, &user->locked_vm);
+ vma->vm_mm->pinned_vm += extra;
+
atomic_inc(&event->mmap_count);
+ } else if (rb) {
+ atomic_dec(&rb->mmap_count);
+ }
+aux_unlock:
mutex_unlock(&event->mmap_mutex);
/*
@@ -4766,7 +4951,7 @@ static void __perf_event_header__init_id(struct perf_event_header *header,
}
if (sample_type & PERF_SAMPLE_TIME)
- data->time = perf_clock();
+ data->time = perf_event_clock(event);
if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER))
data->id = primary_event_id(event);
@@ -5344,6 +5529,8 @@ static void perf_event_task_output(struct perf_event *event,
task_event->event_id.tid = perf_event_tid(event, task);
task_event->event_id.ptid = perf_event_tid(event, current);
+ task_event->event_id.time = perf_event_clock(event);
+
perf_output_put(&handle, task_event->event_id);
perf_event__output_id_sample(event, &handle, &sample);
@@ -5377,7 +5564,7 @@ static void perf_event_task(struct task_struct *task,
/* .ppid */
/* .tid */
/* .ptid */
- .time = perf_clock(),
+ /* .time */
},
};
@@ -5732,6 +5919,40 @@ void perf_event_mmap(struct vm_area_struct *vma)
perf_event_mmap_event(&mmap_event);
}
+void perf_event_aux_event(struct perf_event *event, unsigned long head,
+ unsigned long size, u64 flags)
+{
+ struct perf_output_handle handle;
+ struct perf_sample_data sample;
+ struct perf_aux_event {
+ struct perf_event_header header;
+ u64 offset;
+ u64 size;
+ u64 flags;
+ } rec = {
+ .header = {
+ .type = PERF_RECORD_AUX,
+ .misc = 0,
+ .size = sizeof(rec),
+ },
+ .offset = head,
+ .size = size,
+ .flags = flags,
+ };
+ int ret;
+
+ perf_event_header__init_id(&rec.header, &sample, event);
+ ret = perf_output_begin(&handle, event, rec.header.size);
+
+ if (ret)
+ return;
+
+ perf_output_put(&handle, rec);
+ perf_event__output_id_sample(event, &handle, &sample);
+
+ perf_output_end(&handle);
+}
+
/*
* IRQ throttle logging
*/
@@ -5753,7 +5974,7 @@ static void perf_log_throttle(struct perf_event *event, int enable)
.misc = 0,
.size = sizeof(throttle_event),
},
- .time = perf_clock(),
+ .time = perf_event_clock(event),
.id = primary_event_id(event),
.stream_id = event->id,
};
@@ -5773,6 +5994,44 @@ static void perf_log_throttle(struct perf_event *event, int enable)
perf_output_end(&handle);
}
+static void perf_log_itrace_start(struct perf_event *event)
+{
+ struct perf_output_handle handle;
+ struct perf_sample_data sample;
+ struct perf_aux_event {
+ struct perf_event_header header;
+ u32 pid;
+ u32 tid;
+ } rec;
+ int ret;
+
+ if (event->parent)
+ event = event->parent;
+
+ if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) ||
+ event->hw.itrace_started)
+ return;
+
+ event->hw.itrace_started = 1;
+
+ rec.header.type = PERF_RECORD_ITRACE_START;
+ rec.header.misc = 0;
+ rec.header.size = sizeof(rec);
+ rec.pid = perf_event_pid(event, current);
+ rec.tid = perf_event_tid(event, current);
+
+ perf_event_header__init_id(&rec.header, &sample, event);
+ ret = perf_output_begin(&handle, event, rec.header.size);
+
+ if (ret)
+ return;
+
+ perf_output_put(&handle, rec);
+ perf_event__output_id_sample(event, &handle, &sample);
+
+ perf_output_end(&handle);
+}
+
/*
* Generic event overflow handling, sampling.
*/
@@ -6133,6 +6392,7 @@ static int perf_swevent_add(struct perf_event *event, int flags)
}
hlist_add_head_rcu(&event->hlist_entry, head);
+ perf_event_update_userpage(event);
return 0;
}
@@ -6296,6 +6556,8 @@ static int perf_swevent_init(struct perf_event *event)
static struct pmu perf_swevent = {
.task_ctx_nr = perf_sw_context,
+ .capabilities = PERF_PMU_CAP_NO_NMI,
+
.event_init = perf_swevent_init,
.add = perf_swevent_add,
.del = perf_swevent_del,
@@ -6449,6 +6711,49 @@ static void perf_event_free_filter(struct perf_event *event)
ftrace_profile_free_filter(event);
}
+static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd)
+{
+ struct bpf_prog *prog;
+
+ if (event->attr.type != PERF_TYPE_TRACEPOINT)
+ return -EINVAL;
+
+ if (event->tp_event->prog)
+ return -EEXIST;
+
+ if (!(event->tp_event->flags & TRACE_EVENT_FL_KPROBE))
+ /* bpf programs can only be attached to kprobes */
+ return -EINVAL;
+
+ prog = bpf_prog_get(prog_fd);
+ if (IS_ERR(prog))
+ return PTR_ERR(prog);
+
+ if (prog->type != BPF_PROG_TYPE_KPROBE) {
+ /* valid fd, but invalid bpf program type */
+ bpf_prog_put(prog);
+ return -EINVAL;
+ }
+
+ event->tp_event->prog = prog;
+
+ return 0;
+}
+
+static void perf_event_free_bpf_prog(struct perf_event *event)
+{
+ struct bpf_prog *prog;
+
+ if (!event->tp_event)
+ return;
+
+ prog = event->tp_event->prog;
+ if (prog) {
+ event->tp_event->prog = NULL;
+ bpf_prog_put(prog);
+ }
+}
+
#else
static inline void perf_tp_register(void)
@@ -6464,6 +6769,14 @@ static void perf_event_free_filter(struct perf_event *event)
{
}
+static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd)
+{
+ return -ENOENT;
+}
+
+static void perf_event_free_bpf_prog(struct perf_event *event)
+{
+}
#endif /* CONFIG_EVENT_TRACING */
#ifdef CONFIG_HAVE_HW_BREAKPOINT
@@ -6602,6 +6915,7 @@ static int cpu_clock_event_add(struct perf_event *event, int flags)
{
if (flags & PERF_EF_START)
cpu_clock_event_start(event, flags);
+ perf_event_update_userpage(event);
return 0;
}
@@ -6638,6 +6952,8 @@ static int cpu_clock_event_init(struct perf_event *event)
static struct pmu perf_cpu_clock = {
.task_ctx_nr = perf_sw_context,
+ .capabilities = PERF_PMU_CAP_NO_NMI,
+
.event_init = cpu_clock_event_init,
.add = cpu_clock_event_add,
.del = cpu_clock_event_del,
@@ -6676,6 +6992,7 @@ static int task_clock_event_add(struct perf_event *event, int flags)
{
if (flags & PERF_EF_START)
task_clock_event_start(event, flags);
+ perf_event_update_userpage(event);
return 0;
}
@@ -6716,6 +7033,8 @@ static int task_clock_event_init(struct perf_event *event)
static struct pmu perf_task_clock = {
.task_ctx_nr = perf_sw_context,
+ .capabilities = PERF_PMU_CAP_NO_NMI,
+
.event_init = task_clock_event_init,
.add = task_clock_event_add,
.del = task_clock_event_del,
@@ -6993,6 +7312,7 @@ got_cpu_context:
pmu->event_idx = perf_event_idx_default;
list_add_rcu(&pmu->entry, &pmus);
+ atomic_set(&pmu->exclusive_cnt, 0);
ret = 0;
unlock:
mutex_unlock(&pmus_lock);
@@ -7037,12 +7357,23 @@ EXPORT_SYMBOL_GPL(perf_pmu_unregister);
static int perf_try_init_event(struct pmu *pmu, struct perf_event *event)
{
+ struct perf_event_context *ctx = NULL;
int ret;
if (!try_module_get(pmu->module))
return -ENODEV;
+
+ if (event->group_leader != event) {
+ ctx = perf_event_ctx_lock(event->group_leader);
+ BUG_ON(!ctx);
+ }
+
event->pmu = pmu;
ret = pmu->event_init(event);
+
+ if (ctx)
+ perf_event_ctx_unlock(event->group_leader, ctx);
+
if (ret)
module_put(pmu->module);
@@ -7089,10 +7420,6 @@ static void account_event_cpu(struct perf_event *event, int cpu)
if (event->parent)
return;
- if (has_branch_stack(event)) {
- if (!(event->attach_state & PERF_ATTACH_TASK))
- atomic_inc(&per_cpu(perf_branch_stack_events, cpu));
- }
if (is_cgroup_event(event))
atomic_inc(&per_cpu(perf_cgroup_events, cpu));
}
@@ -7131,7 +7458,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
struct perf_event *group_leader,
struct perf_event *parent_event,
perf_overflow_handler_t overflow_handler,
- void *context)
+ void *context, int cgroup_fd)
{
struct pmu *pmu;
struct perf_event *event;
@@ -7186,18 +7513,18 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
if (task) {
event->attach_state = PERF_ATTACH_TASK;
-
- if (attr->type == PERF_TYPE_TRACEPOINT)
- event->hw.tp_target = task;
-#ifdef CONFIG_HAVE_HW_BREAKPOINT
/*
- * hw_breakpoint is a bit difficult here..
+ * XXX pmu::event_init needs to know what task to account to
+ * and we cannot use the ctx information because we need the
+ * pmu before we get a ctx.
*/
- else if (attr->type == PERF_TYPE_BREAKPOINT)
- event->hw.bp_target = task;
-#endif
+ event->hw.target = task;
}
+ event->clock = &local_clock;
+ if (parent_event)
+ event->clock = parent_event->clock;
+
if (!overflow_handler && parent_event) {
overflow_handler = parent_event->overflow_handler;
context = parent_event->overflow_handler_context;
@@ -7224,6 +7551,15 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP))
goto err_ns;
+ if (!has_branch_stack(event))
+ event->attr.branch_sample_type = 0;
+
+ if (cgroup_fd != -1) {
+ err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader);
+ if (err)
+ goto err_ns;
+ }
+
pmu = perf_init_event(event);
if (!pmu)
goto err_ns;
@@ -7232,21 +7568,30 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
goto err_ns;
}
+ err = exclusive_event_init(event);
+ if (err)
+ goto err_pmu;
+
if (!event->parent) {
if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) {
err = get_callchain_buffers();
if (err)
- goto err_pmu;
+ goto err_per_task;
}
}
return event;
+err_per_task:
+ exclusive_event_destroy(event);
+
err_pmu:
if (event->destroy)
event->destroy(event);
module_put(pmu->module);
err_ns:
+ if (is_cgroup_event(event))
+ perf_detach_cgroup(event);
if (event->ns)
put_pid_ns(event->ns);
kfree(event);
@@ -7409,6 +7754,19 @@ perf_event_set_output(struct perf_event *event, struct perf_event *output_event)
if (output_event->cpu == -1 && output_event->ctx != event->ctx)
goto out;
+ /*
+ * Mixing clocks in the same buffer is trouble you don't need.
+ */
+ if (output_event->clock != event->clock)
+ goto out;
+
+ /*
+ * If both events generate aux data, they must be on the same PMU
+ */
+ if (has_aux(event) && has_aux(output_event) &&
+ event->pmu != output_event->pmu)
+ goto out;
+
set:
mutex_lock(&event->mmap_mutex);
/* Can't redirect output if we've got an active mmap() */
@@ -7441,6 +7799,43 @@ static void mutex_lock_double(struct mutex *a, struct mutex *b)
mutex_lock_nested(b, SINGLE_DEPTH_NESTING);
}
+static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id)
+{
+ bool nmi_safe = false;
+
+ switch (clk_id) {
+ case CLOCK_MONOTONIC:
+ event->clock = &ktime_get_mono_fast_ns;
+ nmi_safe = true;
+ break;
+
+ case CLOCK_MONOTONIC_RAW:
+ event->clock = &ktime_get_raw_fast_ns;
+ nmi_safe = true;
+ break;
+
+ case CLOCK_REALTIME:
+ event->clock = &ktime_get_real_ns;
+ break;
+
+ case CLOCK_BOOTTIME:
+ event->clock = &ktime_get_boot_ns;
+ break;
+
+ case CLOCK_TAI:
+ event->clock = &ktime_get_tai_ns;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI))
+ return -EINVAL;
+
+ return 0;
+}
+
/**
* sys_perf_event_open - open a performance event, associate it to a task/cpu
*
@@ -7465,6 +7860,7 @@ SYSCALL_DEFINE5(perf_event_open,
int move_group = 0;
int err;
int f_flags = O_RDWR;
+ int cgroup_fd = -1;
/* for future expandability... */
if (flags & ~PERF_FLAG_ALL)
@@ -7530,21 +7926,16 @@ SYSCALL_DEFINE5(perf_event_open,
get_online_cpus();
+ if (flags & PERF_FLAG_PID_CGROUP)
+ cgroup_fd = pid;
+
event = perf_event_alloc(&attr, cpu, task, group_leader, NULL,
- NULL, NULL);
+ NULL, NULL, cgroup_fd);
if (IS_ERR(event)) {
err = PTR_ERR(event);
goto err_cpus;
}
- if (flags & PERF_FLAG_PID_CGROUP) {
- err = perf_cgroup_connect(pid, event, &attr, group_leader);
- if (err) {
- __free_event(event);
- goto err_cpus;
- }
- }
-
if (is_sampling_event(event)) {
if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) {
err = -ENOTSUPP;
@@ -7560,6 +7951,12 @@ SYSCALL_DEFINE5(perf_event_open,
*/
pmu = event->pmu;
+ if (attr.use_clockid) {
+ err = perf_event_set_clock(event, attr.clockid);
+ if (err)
+ goto err_alloc;
+ }
+
if (group_leader &&
(is_software_event(event) != is_software_event(group_leader))) {
if (is_software_event(event)) {
@@ -7586,12 +7983,17 @@ SYSCALL_DEFINE5(perf_event_open,
/*
* Get the target context (task or percpu):
*/
- ctx = find_get_context(pmu, task, event->cpu);
+ ctx = find_get_context(pmu, task, event);
if (IS_ERR(ctx)) {
err = PTR_ERR(ctx);
goto err_alloc;
}
+ if ((pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && group_leader) {
+ err = -EBUSY;
+ goto err_context;
+ }
+
if (task) {
put_task_struct(task);
task = NULL;
@@ -7609,6 +8011,11 @@ SYSCALL_DEFINE5(perf_event_open,
*/
if (group_leader->group_leader != group_leader)
goto err_context;
+
+ /* All events in a group should have the same clock */
+ if (group_leader->clock != event->clock)
+ goto err_context;
+
/*
* Do not allow to attach to a group in a different
* task or CPU context:
@@ -7709,6 +8116,13 @@ SYSCALL_DEFINE5(perf_event_open,
get_ctx(ctx);
}
+ if (!exclusive_event_installable(event, ctx)) {
+ err = -EBUSY;
+ mutex_unlock(&ctx->mutex);
+ fput(event_file);
+ goto err_context;
+ }
+
perf_install_in_context(ctx, event, event->cpu);
perf_unpin_context(ctx);
@@ -7781,7 +8195,7 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
*/
event = perf_event_alloc(attr, cpu, task, NULL, NULL,
- overflow_handler, context);
+ overflow_handler, context, -1);
if (IS_ERR(event)) {
err = PTR_ERR(event);
goto err;
@@ -7792,7 +8206,7 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
account_event(event);
- ctx = find_get_context(event->pmu, task, cpu);
+ ctx = find_get_context(event->pmu, task, event);
if (IS_ERR(ctx)) {
err = PTR_ERR(ctx);
goto err_free;
@@ -7800,6 +8214,14 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
WARN_ON_ONCE(ctx->parent_ctx);
mutex_lock(&ctx->mutex);
+ if (!exclusive_event_installable(event, ctx)) {
+ mutex_unlock(&ctx->mutex);
+ perf_unpin_context(ctx);
+ put_ctx(ctx);
+ err = -EBUSY;
+ goto err_free;
+ }
+
perf_install_in_context(ctx, event, cpu);
perf_unpin_context(ctx);
mutex_unlock(&ctx->mutex);
@@ -8142,7 +8564,7 @@ inherit_event(struct perf_event *parent_event,
parent_event->cpu,
child,
group_leader, parent_event,
- NULL, NULL);
+ NULL, NULL, -1);
if (IS_ERR(child_event))
return child_event;