#include <linux/ftrace_event.h>
#include <linux/hw_breakpoint.h>
+#include "internal.h"
+
#include <asm/irq_regs.h>
struct remote_function_call {
local_irq_restore(flags);
}
-static inline void perf_cgroup_sched_out(struct task_struct *task)
+static inline void perf_cgroup_sched_out(struct task_struct *task,
+ struct task_struct *next)
{
- perf_cgroup_switch(task, PERF_CGROUP_SWOUT);
+ struct perf_cgroup *cgrp1;
+ struct perf_cgroup *cgrp2 = NULL;
+
+ /*
+ * we come here when we know perf_cgroup_events > 0
+ */
+ cgrp1 = perf_cgroup_from_task(task);
+
+ /*
+ * next is NULL when called from perf_event_enable_on_exec()
+ * that will systematically cause a cgroup_switch()
+ */
+ if (next)
+ cgrp2 = perf_cgroup_from_task(next);
+
+ /*
+ * only schedule out current cgroup events if we know
+ * that we are switching to a different cgroup. Otherwise,
+ * do no touch the cgroup events.
+ */
+ if (cgrp1 != cgrp2)
+ perf_cgroup_switch(task, PERF_CGROUP_SWOUT);
}
-static inline void perf_cgroup_sched_in(struct task_struct *task)
+static inline void perf_cgroup_sched_in(struct task_struct *prev,
+ struct task_struct *task)
{
- perf_cgroup_switch(task, PERF_CGROUP_SWIN);
+ struct perf_cgroup *cgrp1;
+ struct perf_cgroup *cgrp2 = NULL;
+
+ /*
+ * we come here when we know perf_cgroup_events > 0
+ */
+ cgrp1 = perf_cgroup_from_task(task);
+
+ /* prev can never be NULL */
+ cgrp2 = perf_cgroup_from_task(prev);
+
+ /*
+ * only need to schedule in cgroup events if we are changing
+ * cgroup during ctxsw. Cgroup events were not scheduled
+ * out of ctxsw out if that was not the case.
+ */
+ if (cgrp1 != cgrp2)
+ perf_cgroup_switch(task, PERF_CGROUP_SWIN);
}
static inline int perf_cgroup_connect(int fd, struct perf_event *event,
{
}
-static inline void perf_cgroup_sched_out(struct task_struct *task)
+static inline void perf_cgroup_sched_out(struct task_struct *task,
+ struct task_struct *next)
{
}
-static inline void perf_cgroup_sched_in(struct task_struct *task)
+static inline void perf_cgroup_sched_in(struct task_struct *prev,
+ struct task_struct *task)
{
}
/*
* Update the total_time_enabled and total_time_running fields for a event.
+ * The caller of this function needs to hold the ctx->lock.
*/
static void update_event_times(struct perf_event *event)
{
raw_spin_lock(&ctx->lock);
event_sched_out(event, cpuctx, ctx);
list_del_event(event, ctx);
+ if (!ctx->nr_events && cpuctx->task_ctx == ctx) {
+ ctx->is_active = 0;
+ cpuctx->task_ctx = NULL;
+ }
raw_spin_unlock(&ctx->lock);
return 0;
event->tstamp_stopped = tstamp;
}
-static void perf_event_context_sched_in(struct perf_event_context *ctx,
- struct task_struct *tsk);
+static void task_ctx_sched_out(struct perf_event_context *ctx);
+static void
+ctx_sched_in(struct perf_event_context *ctx,
+ struct perf_cpu_context *cpuctx,
+ enum event_type_t event_type,
+ struct task_struct *task);
+
+static void perf_event_sched_in(struct perf_cpu_context *cpuctx,
+ struct perf_event_context *ctx,
+ struct task_struct *task)
+{
+ cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task);
+ if (ctx)
+ ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task);
+ cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task);
+ if (ctx)
+ ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task);
+}
/*
* Cross CPU call to install and enable a performance event
{
struct perf_event *event = info;
struct perf_event_context *ctx = event->ctx;
- struct perf_event *leader = event->group_leader;
struct perf_cpu_context *cpuctx = __get_cpu_context(ctx);
- int err;
+ struct perf_event_context *task_ctx = cpuctx->task_ctx;
+ struct task_struct *task = current;
+
+ perf_ctx_lock(cpuctx, task_ctx);
+ perf_pmu_disable(cpuctx->ctx.pmu);
/*
- * In case we're installing a new context to an already running task,
- * could also happen before perf_event_task_sched_in() on architectures
- * which do context switches with IRQs enabled.
+ * If there was an active task_ctx schedule it out.
*/
- if (ctx->task && !cpuctx->task_ctx)
- perf_event_context_sched_in(ctx, ctx->task);
+ if (task_ctx)
+ task_ctx_sched_out(task_ctx);
+
+ /*
+ * If the context we're installing events in is not the
+ * active task_ctx, flip them.
+ */
+ if (ctx->task && task_ctx != ctx) {
+ if (task_ctx)
+ raw_spin_unlock(&task_ctx->lock);
+ raw_spin_lock(&ctx->lock);
+ task_ctx = ctx;
+ }
+
+ if (task_ctx) {
+ cpuctx->task_ctx = task_ctx;
+ task = task_ctx->task;
+ }
+
+ cpu_ctx_sched_out(cpuctx, EVENT_ALL);
- raw_spin_lock(&ctx->lock);
- ctx->is_active = 1;
update_context_time(ctx);
/*
* update cgrp time only if current cgrp
add_event_to_ctx(event, ctx);
- if (!event_filter_match(event))
- goto unlock;
-
/*
- * Don't put the event on if it is disabled or if
- * it is in a group and the group isn't on.
+ * Schedule everything back in
*/
- if (event->state != PERF_EVENT_STATE_INACTIVE ||
- (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE))
- goto unlock;
-
- /*
- * An exclusive event can't go on if there are already active
- * hardware events, and no hardware event can go on if there
- * is already an exclusive event on.
- */
- if (!group_can_go_on(event, cpuctx, 1))
- err = -EEXIST;
- else
- err = event_sched_in(event, cpuctx, ctx);
-
- if (err) {
- /*
- * This event couldn't go on. If it is in a group
- * then we have to pull the whole group off.
- * If the event group is pinned then put it in error state.
- */
- if (leader != event)
- group_sched_out(leader, cpuctx, ctx);
- if (leader->attr.pinned) {
- update_group_times(leader);
- leader->state = PERF_EVENT_STATE_ERROR;
- }
- }
+ perf_event_sched_in(cpuctx, task_ctx, task);
-unlock:
- raw_spin_unlock(&ctx->lock);
+ perf_pmu_enable(cpuctx->ctx.pmu);
+ perf_ctx_unlock(cpuctx, task_ctx);
return 0;
}
raw_spin_unlock_irq(&ctx->lock);
}
-static int perf_event_refresh(struct perf_event *event, int refresh)
+int perf_event_refresh(struct perf_event *event, int refresh)
{
/*
* not supported on inherited events
return 0;
}
+EXPORT_SYMBOL_GPL(perf_event_refresh);
static void ctx_sched_out(struct perf_event_context *ctx,
struct perf_cpu_context *cpuctx,
enum event_type_t event_type)
{
struct perf_event *event;
+ int is_active = ctx->is_active;
- ctx->is_active = 0;
+ ctx->is_active &= ~event_type;
if (likely(!ctx->nr_events))
return;
return;
perf_pmu_disable(ctx->pmu);
- if (event_type & EVENT_PINNED) {
+ if ((is_active & EVENT_PINNED) && (event_type & EVENT_PINNED)) {
list_for_each_entry(event, &ctx->pinned_groups, group_entry)
group_sched_out(event, cpuctx, ctx);
}
- if (event_type & EVENT_FLEXIBLE) {
+ if ((is_active & EVENT_FLEXIBLE) && (event_type & EVENT_FLEXIBLE)) {
list_for_each_entry(event, &ctx->flexible_groups, group_entry)
group_sched_out(event, cpuctx, ctx);
}
* cgroup event are system-wide mode only
*/
if (atomic_read(&__get_cpu_var(perf_cgroup_events)))
- perf_cgroup_sched_out(task);
+ perf_cgroup_sched_out(task, next);
}
-static void task_ctx_sched_out(struct perf_event_context *ctx,
- enum event_type_t event_type)
+static void task_ctx_sched_out(struct perf_event_context *ctx)
{
struct perf_cpu_context *cpuctx = __get_cpu_context(ctx);
if (WARN_ON_ONCE(ctx != cpuctx->task_ctx))
return;
- ctx_sched_out(ctx, cpuctx, event_type);
+ ctx_sched_out(ctx, cpuctx, EVENT_ALL);
cpuctx->task_ctx = NULL;
}
struct task_struct *task)
{
u64 now;
+ int is_active = ctx->is_active;
- ctx->is_active = 1;
+ ctx->is_active |= event_type;
if (likely(!ctx->nr_events))
return;
* First go through the list and put on any pinned groups
* in order to give them the best chance of going on.
*/
- if (event_type & EVENT_PINNED)
+ if (!(is_active & EVENT_PINNED) && (event_type & EVENT_PINNED))
ctx_pinned_sched_in(ctx, cpuctx);
/* Then walk through the lower prio flexible groups */
- if (event_type & EVENT_FLEXIBLE)
+ if (!(is_active & EVENT_FLEXIBLE) && (event_type & EVENT_FLEXIBLE))
ctx_flexible_sched_in(ctx, cpuctx);
}
ctx_sched_in(ctx, cpuctx, event_type, task);
}
-static void task_ctx_sched_in(struct perf_event_context *ctx,
- enum event_type_t event_type)
-{
- struct perf_cpu_context *cpuctx;
-
- cpuctx = __get_cpu_context(ctx);
- if (cpuctx->task_ctx == ctx)
- return;
-
- ctx_sched_in(ctx, cpuctx, event_type, NULL);
- cpuctx->task_ctx = ctx;
-}
-
static void perf_event_context_sched_in(struct perf_event_context *ctx,
struct task_struct *task)
{
*/
cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
- ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task);
- cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task);
- ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task);
+ perf_event_sched_in(cpuctx, ctx, task);
cpuctx->task_ctx = ctx;
* accessing the event control register. If a NMI hits, then it will
* keep the event running.
*/
-void __perf_event_task_sched_in(struct task_struct *task)
+void __perf_event_task_sched_in(struct task_struct *prev,
+ struct task_struct *task)
{
struct perf_event_context *ctx;
int ctxn;
* cgroup event are system-wide mode only
*/
if (atomic_read(&__get_cpu_var(perf_cgroup_events)))
- perf_cgroup_sched_in(task);
+ perf_cgroup_sched_in(prev, task);
}
static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count)
cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
if (ctx)
- task_ctx_sched_out(ctx, EVENT_FLEXIBLE);
+ ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE);
rotate_ctx(&cpuctx->ctx);
if (ctx)
rotate_ctx(ctx);
- cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, current);
- if (ctx)
- task_ctx_sched_in(ctx, EVENT_FLEXIBLE);
+ perf_event_sched_in(cpuctx, ctx, current);
done:
if (remove)
* ctxswin cgroup events which are already scheduled
* in.
*/
- perf_cgroup_sched_out(current);
+ perf_cgroup_sched_out(current, NULL);
raw_spin_lock(&ctx->lock);
- task_ctx_sched_out(ctx, EVENT_ALL);
+ task_ctx_sched_out(ctx);
list_for_each_entry(event, &ctx->pinned_groups, group_entry) {
ret = event_enable_on_exec(event, ctx);
kfree(event);
}
-static void perf_buffer_put(struct perf_buffer *buffer);
+static void ring_buffer_put(struct ring_buffer *rb);
static void free_event(struct perf_event *event)
{
}
}
- if (event->buffer) {
- perf_buffer_put(event->buffer);
- event->buffer = NULL;
+ if (event->rb) {
+ ring_buffer_put(event->rb);
+ event->rb = NULL;
}
if (is_cgroup_event(event))
{
struct perf_event_context *ctx = event->ctx;
- /*
- * Remove from the PMU, can't get re-enabled since we got
- * here because the last ref went.
- */
- perf_event_disable(event);
-
WARN_ON_ONCE(ctx->parent_ctx);
/*
* There are two ways this annotation is useful:
mutex_lock_nested(&ctx->mutex, SINGLE_DEPTH_NESTING);
raw_spin_lock_irq(&ctx->lock);
perf_group_detach(event);
- list_del_event(event, ctx);
raw_spin_unlock_irq(&ctx->lock);
+ perf_remove_from_context(event);
mutex_unlock(&ctx->mutex);
free_event(event);
static unsigned int perf_poll(struct file *file, poll_table *wait)
{
struct perf_event *event = file->private_data;
- struct perf_buffer *buffer;
+ struct ring_buffer *rb;
unsigned int events = POLL_HUP;
rcu_read_lock();
- buffer = rcu_dereference(event->buffer);
- if (buffer)
- events = atomic_xchg(&buffer->poll, 0);
+ rb = rcu_dereference(event->rb);
+ if (rb)
+ events = atomic_xchg(&rb->poll, 0);
rcu_read_unlock();
poll_wait(file, &event->waitq, wait);
return event->hw.idx + 1 - PERF_EVENT_INDEX_OFFSET;
}
+static void calc_timer_values(struct perf_event *event,
+ u64 *enabled,
+ u64 *running)
+{
+ u64 now, ctx_time;
+
+ now = perf_clock();
+ ctx_time = event->shadow_ctx_time + now;
+ *enabled = ctx_time - event->tstamp_enabled;
+ *running = ctx_time - event->tstamp_running;
+}
+
/*
* Callers need to ensure there can be no nesting of this function, otherwise
* the seqlock logic goes bad. We can not serialize this because the arch
void perf_event_update_userpage(struct perf_event *event)
{
struct perf_event_mmap_page *userpg;
- struct perf_buffer *buffer;
+ struct ring_buffer *rb;
+ u64 enabled, running;
rcu_read_lock();
- buffer = rcu_dereference(event->buffer);
- if (!buffer)
+ /*
+ * compute total_time_enabled, total_time_running
+ * based on snapshot values taken when the event
+ * was last scheduled in.
+ *
+ * we cannot simply called update_context_time()
+ * because of locking issue as we can be called in
+ * NMI context
+ */
+ calc_timer_values(event, &enabled, &running);
+ rb = rcu_dereference(event->rb);
+ if (!rb)
goto unlock;
- userpg = buffer->user_page;
+ userpg = rb->user_page;
/*
* Disable preemption so as to not let the corresponding user-space
if (event->state == PERF_EVENT_STATE_ACTIVE)
userpg->offset -= local64_read(&event->hw.prev_count);
- userpg->time_enabled = event->total_time_enabled +
+ userpg->time_enabled = enabled +
atomic64_read(&event->child_total_time_enabled);
- userpg->time_running = event->total_time_running +
+ userpg->time_running = running +
atomic64_read(&event->child_total_time_running);
barrier();
rcu_read_unlock();
}
-static unsigned long perf_data_size(struct perf_buffer *buffer);
-
-static void
-perf_buffer_init(struct perf_buffer *buffer, long watermark, int flags)
-{
- long max_size = perf_data_size(buffer);
-
- if (watermark)
- buffer->watermark = min(max_size, watermark);
-
- if (!buffer->watermark)
- buffer->watermark = max_size / 2;
-
- if (flags & PERF_BUFFER_WRITABLE)
- buffer->writable = 1;
-
- atomic_set(&buffer->refcount, 1);
-}
-
-#ifndef CONFIG_PERF_USE_VMALLOC
-
-/*
- * Back perf_mmap() with regular GFP_KERNEL-0 pages.
- */
-
-static struct page *
-perf_mmap_to_page(struct perf_buffer *buffer, unsigned long pgoff)
-{
- if (pgoff > buffer->nr_pages)
- return NULL;
-
- if (pgoff == 0)
- return virt_to_page(buffer->user_page);
-
- return virt_to_page(buffer->data_pages[pgoff - 1]);
-}
-
-static void *perf_mmap_alloc_page(int cpu)
-{
- struct page *page;
- int node;
-
- node = (cpu == -1) ? cpu : cpu_to_node(cpu);
- page = alloc_pages_node(node, GFP_KERNEL | __GFP_ZERO, 0);
- if (!page)
- return NULL;
-
- return page_address(page);
-}
-
-static struct perf_buffer *
-perf_buffer_alloc(int nr_pages, long watermark, int cpu, int flags)
-{
- struct perf_buffer *buffer;
- unsigned long size;
- int i;
-
- size = sizeof(struct perf_buffer);
- size += nr_pages * sizeof(void *);
-
- buffer = kzalloc(size, GFP_KERNEL);
- if (!buffer)
- goto fail;
-
- buffer->user_page = perf_mmap_alloc_page(cpu);
- if (!buffer->user_page)
- goto fail_user_page;
-
- for (i = 0; i < nr_pages; i++) {
- buffer->data_pages[i] = perf_mmap_alloc_page(cpu);
- if (!buffer->data_pages[i])
- goto fail_data_pages;
- }
-
- buffer->nr_pages = nr_pages;
-
- perf_buffer_init(buffer, watermark, flags);
-
- return buffer;
-
-fail_data_pages:
- for (i--; i >= 0; i--)
- free_page((unsigned long)buffer->data_pages[i]);
-
- free_page((unsigned long)buffer->user_page);
-
-fail_user_page:
- kfree(buffer);
-
-fail:
- return NULL;
-}
-
-static void perf_mmap_free_page(unsigned long addr)
-{
- struct page *page = virt_to_page((void *)addr);
-
- page->mapping = NULL;
- __free_page(page);
-}
-
-static void perf_buffer_free(struct perf_buffer *buffer)
-{
- int i;
-
- perf_mmap_free_page((unsigned long)buffer->user_page);
- for (i = 0; i < buffer->nr_pages; i++)
- perf_mmap_free_page((unsigned long)buffer->data_pages[i]);
- kfree(buffer);
-}
-
-static inline int page_order(struct perf_buffer *buffer)
-{
- return 0;
-}
-
-#else
-
-/*
- * Back perf_mmap() with vmalloc memory.
- *
- * Required for architectures that have d-cache aliasing issues.
- */
-
-static inline int page_order(struct perf_buffer *buffer)
-{
- return buffer->page_order;
-}
-
-static struct page *
-perf_mmap_to_page(struct perf_buffer *buffer, unsigned long pgoff)
-{
- if (pgoff > (1UL << page_order(buffer)))
- return NULL;
-
- return vmalloc_to_page((void *)buffer->user_page + pgoff * PAGE_SIZE);
-}
-
-static void perf_mmap_unmark_page(void *addr)
-{
- struct page *page = vmalloc_to_page(addr);
-
- page->mapping = NULL;
-}
-
-static void perf_buffer_free_work(struct work_struct *work)
-{
- struct perf_buffer *buffer;
- void *base;
- int i, nr;
-
- buffer = container_of(work, struct perf_buffer, work);
- nr = 1 << page_order(buffer);
-
- base = buffer->user_page;
- for (i = 0; i < nr + 1; i++)
- perf_mmap_unmark_page(base + (i * PAGE_SIZE));
-
- vfree(base);
- kfree(buffer);
-}
-
-static void perf_buffer_free(struct perf_buffer *buffer)
-{
- schedule_work(&buffer->work);
-}
-
-static struct perf_buffer *
-perf_buffer_alloc(int nr_pages, long watermark, int cpu, int flags)
-{
- struct perf_buffer *buffer;
- unsigned long size;
- void *all_buf;
-
- size = sizeof(struct perf_buffer);
- size += sizeof(void *);
-
- buffer = kzalloc(size, GFP_KERNEL);
- if (!buffer)
- goto fail;
-
- INIT_WORK(&buffer->work, perf_buffer_free_work);
-
- all_buf = vmalloc_user((nr_pages + 1) * PAGE_SIZE);
- if (!all_buf)
- goto fail_all_buf;
-
- buffer->user_page = all_buf;
- buffer->data_pages[0] = all_buf + PAGE_SIZE;
- buffer->page_order = ilog2(nr_pages);
- buffer->nr_pages = 1;
-
- perf_buffer_init(buffer, watermark, flags);
-
- return buffer;
-
-fail_all_buf:
- kfree(buffer);
-
-fail:
- return NULL;
-}
-
-#endif
-
-static unsigned long perf_data_size(struct perf_buffer *buffer)
-{
- return buffer->nr_pages << (PAGE_SHIFT + page_order(buffer));
-}
-
static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
struct perf_event *event = vma->vm_file->private_data;
- struct perf_buffer *buffer;
+ struct ring_buffer *rb;
int ret = VM_FAULT_SIGBUS;
if (vmf->flags & FAULT_FLAG_MKWRITE) {
}
rcu_read_lock();
- buffer = rcu_dereference(event->buffer);
- if (!buffer)
+ rb = rcu_dereference(event->rb);
+ if (!rb)
goto unlock;
if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE))
goto unlock;
- vmf->page = perf_mmap_to_page(buffer, vmf->pgoff);
+ vmf->page = perf_mmap_to_page(rb, vmf->pgoff);
if (!vmf->page)
goto unlock;
return ret;
}
-static void perf_buffer_free_rcu(struct rcu_head *rcu_head)
+static void rb_free_rcu(struct rcu_head *rcu_head)
{
- struct perf_buffer *buffer;
+ struct ring_buffer *rb;
- buffer = container_of(rcu_head, struct perf_buffer, rcu_head);
- perf_buffer_free(buffer);
+ rb = container_of(rcu_head, struct ring_buffer, rcu_head);
+ rb_free(rb);
}
-static struct perf_buffer *perf_buffer_get(struct perf_event *event)
+static struct ring_buffer *ring_buffer_get(struct perf_event *event)
{
- struct perf_buffer *buffer;
+ struct ring_buffer *rb;
rcu_read_lock();
- buffer = rcu_dereference(event->buffer);
- if (buffer) {
- if (!atomic_inc_not_zero(&buffer->refcount))
- buffer = NULL;
+ rb = rcu_dereference(event->rb);
+ if (rb) {
+ if (!atomic_inc_not_zero(&rb->refcount))
+ rb = NULL;
}
rcu_read_unlock();
- return buffer;
+ return rb;
}
-static void perf_buffer_put(struct perf_buffer *buffer)
+static void ring_buffer_put(struct ring_buffer *rb)
{
- if (!atomic_dec_and_test(&buffer->refcount))
+ if (!atomic_dec_and_test(&rb->refcount))
return;
- call_rcu(&buffer->rcu_head, perf_buffer_free_rcu);
+ call_rcu(&rb->rcu_head, rb_free_rcu);
}
static void perf_mmap_open(struct vm_area_struct *vma)
struct perf_event *event = vma->vm_file->private_data;
if (atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) {
- unsigned long size = perf_data_size(event->buffer);
+ unsigned long size = perf_data_size(event->rb);
struct user_struct *user = event->mmap_user;
- struct perf_buffer *buffer = event->buffer;
+ struct ring_buffer *rb = event->rb;
atomic_long_sub((size >> PAGE_SHIFT) + 1, &user->locked_vm);
vma->vm_mm->locked_vm -= event->mmap_locked;
- rcu_assign_pointer(event->buffer, NULL);
+ rcu_assign_pointer(event->rb, NULL);
mutex_unlock(&event->mmap_mutex);
- perf_buffer_put(buffer);
+ ring_buffer_put(rb);
free_uid(user);
}
}
unsigned long user_locked, user_lock_limit;
struct user_struct *user = current_user();
unsigned long locked, lock_limit;
- struct perf_buffer *buffer;
+ struct ring_buffer *rb;
unsigned long vma_size;
unsigned long nr_pages;
long user_extra, extra;
/*
* Don't allow mmap() of inherited per-task counters. This would
* create a performance issue due to all children writing to the
- * same buffer.
+ * same rb.
*/
if (event->cpu == -1 && event->attr.inherit)
return -EINVAL;
nr_pages = (vma_size / PAGE_SIZE) - 1;
/*
- * If we have buffer pages ensure they're a power-of-two number, so we
+ * If we have rb pages ensure they're a power-of-two number, so we
* can do bitmasks instead of modulo.
*/
if (nr_pages != 0 && !is_power_of_2(nr_pages))
WARN_ON_ONCE(event->ctx->parent_ctx);
mutex_lock(&event->mmap_mutex);
- if (event->buffer) {
- if (event->buffer->nr_pages == nr_pages)
- atomic_inc(&event->buffer->refcount);
+ if (event->rb) {
+ if (event->rb->nr_pages == nr_pages)
+ atomic_inc(&event->rb->refcount);
else
ret = -EINVAL;
goto unlock;
goto unlock;
}
- WARN_ON(event->buffer);
+ WARN_ON(event->rb);
if (vma->vm_flags & VM_WRITE)
- flags |= PERF_BUFFER_WRITABLE;
+ flags |= RING_BUFFER_WRITABLE;
+
+ rb = rb_alloc(nr_pages,
+ event->attr.watermark ? event->attr.wakeup_watermark : 0,
+ event->cpu, flags);
- buffer = perf_buffer_alloc(nr_pages, event->attr.wakeup_watermark,
- event->cpu, flags);
- if (!buffer) {
+ if (!rb) {
ret = -ENOMEM;
goto unlock;
}
- rcu_assign_pointer(event->buffer, buffer);
+ rcu_assign_pointer(event->rb, rb);
atomic_long_add(user_extra, &user->locked_vm);
event->mmap_locked = extra;
}
EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks);
-/*
- * Output
- */
-static bool perf_output_space(struct perf_buffer *buffer, unsigned long tail,
- unsigned long offset, unsigned long head)
-{
- unsigned long mask;
-
- if (!buffer->writable)
- return true;
-
- mask = perf_data_size(buffer) - 1;
-
- offset = (offset - tail) & mask;
- head = (head - tail) & mask;
-
- if ((int)(head - offset) < 0)
- return false;
-
- return true;
-}
-
-static void perf_output_wakeup(struct perf_output_handle *handle)
-{
- atomic_set(&handle->buffer->poll, POLL_IN);
-
- if (handle->nmi) {
- handle->event->pending_wakeup = 1;
- irq_work_queue(&handle->event->pending);
- } else
- perf_event_wakeup(handle->event);
-}
-
-/*
- * We need to ensure a later event_id doesn't publish a head when a former
- * event isn't done writing. However since we need to deal with NMIs we
- * cannot fully serialize things.
- *
- * We only publish the head (and generate a wakeup) when the outer-most
- * event completes.
- */
-static void perf_output_get_handle(struct perf_output_handle *handle)
-{
- struct perf_buffer *buffer = handle->buffer;
-
- preempt_disable();
- local_inc(&buffer->nest);
- handle->wakeup = local_read(&buffer->wakeup);
-}
-
-static void perf_output_put_handle(struct perf_output_handle *handle)
-{
- struct perf_buffer *buffer = handle->buffer;
- unsigned long head;
-
-again:
- head = local_read(&buffer->head);
-
- /*
- * IRQ/NMI can happen here, which means we can miss a head update.
- */
-
- if (!local_dec_and_test(&buffer->nest))
- goto out;
-
- /*
- * Publish the known good head. Rely on the full barrier implied
- * by atomic_dec_and_test() order the buffer->head read and this
- * write.
- */
- buffer->user_page->data_head = head;
-
- /*
- * Now check if we missed an update, rely on the (compiler)
- * barrier in atomic_dec_and_test() to re-read buffer->head.
- */
- if (unlikely(head != local_read(&buffer->head))) {
- local_inc(&buffer->nest);
- goto again;
- }
-
- if (handle->wakeup != local_read(&buffer->wakeup))
- perf_output_wakeup(handle);
-
-out:
- preempt_enable();
-}
-
-__always_inline void perf_output_copy(struct perf_output_handle *handle,
- const void *buf, unsigned int len)
-{
- do {
- unsigned long size = min_t(unsigned long, handle->size, len);
-
- memcpy(handle->addr, buf, size);
-
- len -= size;
- handle->addr += size;
- buf += size;
- handle->size -= size;
- if (!handle->size) {
- struct perf_buffer *buffer = handle->buffer;
-
- handle->page++;
- handle->page &= buffer->nr_pages - 1;
- handle->addr = buffer->data_pages[handle->page];
- handle->size = PAGE_SIZE << page_order(buffer);
- }
- } while (len);
-}
-
static void __perf_event_header__init_id(struct perf_event_header *header,
struct perf_sample_data *data,
struct perf_event *event)
}
}
-static void perf_event_header__init_id(struct perf_event_header *header,
- struct perf_sample_data *data,
- struct perf_event *event)
+void perf_event_header__init_id(struct perf_event_header *header,
+ struct perf_sample_data *data,
+ struct perf_event *event)
{
if (event->attr.sample_id_all)
__perf_event_header__init_id(header, data, event);
perf_output_put(handle, data->cpu_entry);
}
-static void perf_event__output_id_sample(struct perf_event *event,
- struct perf_output_handle *handle,
- struct perf_sample_data *sample)
+void perf_event__output_id_sample(struct perf_event *event,
+ struct perf_output_handle *handle,
+ struct perf_sample_data *sample)
{
if (event->attr.sample_id_all)
__perf_event__output_id_sample(handle, sample);
}
-int perf_output_begin(struct perf_output_handle *handle,
- struct perf_event *event, unsigned int size,
- int nmi, int sample)
-{
- struct perf_buffer *buffer;
- unsigned long tail, offset, head;
- int have_lost;
- struct perf_sample_data sample_data;
- struct {
- struct perf_event_header header;
- u64 id;
- u64 lost;
- } lost_event;
-
- rcu_read_lock();
- /*
- * For inherited events we send all the output towards the parent.
- */
- if (event->parent)
- event = event->parent;
-
- buffer = rcu_dereference(event->buffer);
- if (!buffer)
- goto out;
-
- handle->buffer = buffer;
- handle->event = event;
- handle->nmi = nmi;
- handle->sample = sample;
-
- if (!buffer->nr_pages)
- goto out;
-
- have_lost = local_read(&buffer->lost);
- if (have_lost) {
- lost_event.header.size = sizeof(lost_event);
- perf_event_header__init_id(&lost_event.header, &sample_data,
- event);
- size += lost_event.header.size;
- }
-
- perf_output_get_handle(handle);
-
- do {
- /*
- * Userspace could choose to issue a mb() before updating the
- * tail pointer. So that all reads will be completed before the
- * write is issued.
- */
- tail = ACCESS_ONCE(buffer->user_page->data_tail);
- smp_rmb();
- offset = head = local_read(&buffer->head);
- head += size;
- if (unlikely(!perf_output_space(buffer, tail, offset, head)))
- goto fail;
- } while (local_cmpxchg(&buffer->head, offset, head) != offset);
-
- if (head - local_read(&buffer->wakeup) > buffer->watermark)
- local_add(buffer->watermark, &buffer->wakeup);
-
- handle->page = offset >> (PAGE_SHIFT + page_order(buffer));
- handle->page &= buffer->nr_pages - 1;
- handle->size = offset & ((PAGE_SIZE << page_order(buffer)) - 1);
- handle->addr = buffer->data_pages[handle->page];
- handle->addr += handle->size;
- handle->size = (PAGE_SIZE << page_order(buffer)) - handle->size;
-
- if (have_lost) {
- lost_event.header.type = PERF_RECORD_LOST;
- lost_event.header.misc = 0;
- lost_event.id = event->id;
- lost_event.lost = local_xchg(&buffer->lost, 0);
-
- perf_output_put(handle, lost_event);
- perf_event__output_id_sample(event, handle, &sample_data);
- }
-
- return 0;
-
-fail:
- local_inc(&buffer->lost);
- perf_output_put_handle(handle);
-out:
- rcu_read_unlock();
-
- return -ENOSPC;
-}
-
-void perf_output_end(struct perf_output_handle *handle)
-{
- struct perf_event *event = handle->event;
- struct perf_buffer *buffer = handle->buffer;
-
- int wakeup_events = event->attr.wakeup_events;
-
- if (handle->sample && wakeup_events) {
- int events = local_inc_return(&buffer->events);
- if (events >= wakeup_events) {
- local_sub(wakeup_events, &buffer->events);
- local_inc(&buffer->wakeup);
- }
- }
-
- perf_output_put_handle(handle);
- rcu_read_unlock();
-}
-
static void perf_output_read_one(struct perf_output_handle *handle,
struct perf_event *event,
u64 enabled, u64 running)
if (read_format & PERF_FORMAT_ID)
values[n++] = primary_event_id(event);
- perf_output_copy(handle, values, n * sizeof(u64));
+ __output_copy(handle, values, n * sizeof(u64));
}
/*
if (read_format & PERF_FORMAT_ID)
values[n++] = primary_event_id(leader);
- perf_output_copy(handle, values, n * sizeof(u64));
+ __output_copy(handle, values, n * sizeof(u64));
list_for_each_entry(sub, &leader->sibling_list, group_entry) {
n = 0;
if (read_format & PERF_FORMAT_ID)
values[n++] = primary_event_id(sub);
- perf_output_copy(handle, values, n * sizeof(u64));
+ __output_copy(handle, values, n * sizeof(u64));
}
}
static void perf_output_read(struct perf_output_handle *handle,
struct perf_event *event)
{
- u64 enabled = 0, running = 0, now, ctx_time;
+ u64 enabled = 0, running = 0;
u64 read_format = event->attr.read_format;
/*
* because of locking issue as we are called in
* NMI context
*/
- if (read_format & PERF_FORMAT_TOTAL_TIMES) {
- now = perf_clock();
- ctx_time = event->shadow_ctx_time + now;
- enabled = ctx_time - event->tstamp_enabled;
- running = ctx_time - event->tstamp_running;
- }
+ if (read_format & PERF_FORMAT_TOTAL_TIMES)
+ calc_timer_values(event, &enabled, &running);
if (event->attr.read_format & PERF_FORMAT_GROUP)
perf_output_read_group(handle, event, enabled, running);
size *= sizeof(u64);
- perf_output_copy(handle, data->callchain, size);
+ __output_copy(handle, data->callchain, size);
} else {
u64 nr = 0;
perf_output_put(handle, nr);
if (sample_type & PERF_SAMPLE_RAW) {
if (data->raw) {
perf_output_put(handle, data->raw->size);
- perf_output_copy(handle, data->raw->data,
- data->raw->size);
+ __output_copy(handle, data->raw->data,
+ data->raw->size);
} else {
struct {
u32 size;
perf_output_put(handle, raw);
}
}
+
+ if (!event->attr.watermark) {
+ int wakeup_events = event->attr.wakeup_events;
+
+ if (wakeup_events) {
+ struct ring_buffer *rb = handle->rb;
+ int events = local_inc_return(&rb->events);
+
+ if (events >= wakeup_events) {
+ local_sub(wakeup_events, &rb->events);
+ local_inc(&rb->wakeup);
+ }
+ }
+ }
}
void perf_prepare_sample(struct perf_event_header *header,
}
}
-static void perf_event_output(struct perf_event *event, int nmi,
+static void perf_event_output(struct perf_event *event,
struct perf_sample_data *data,
struct pt_regs *regs)
{
perf_prepare_sample(&header, data, event, regs);
- if (perf_output_begin(&handle, event, header.size, nmi, 1))
+ if (perf_output_begin(&handle, event, header.size))
goto exit;
perf_output_sample(&handle, &header, data, event);
int ret;
perf_event_header__init_id(&read_event.header, &sample, event);
- ret = perf_output_begin(&handle, event, read_event.header.size, 0, 0);
+ ret = perf_output_begin(&handle, event, read_event.header.size);
if (ret)
return;
perf_event_header__init_id(&task_event->event_id.header, &sample, event);
ret = perf_output_begin(&handle, event,
- task_event->event_id.header.size, 0, 0);
+ task_event->event_id.header.size);
if (ret)
goto out;
perf_event_header__init_id(&comm_event->event_id.header, &sample, event);
ret = perf_output_begin(&handle, event,
- comm_event->event_id.header.size, 0, 0);
+ comm_event->event_id.header.size);
if (ret)
goto out;
comm_event->event_id.tid = perf_event_tid(event, comm_event->task);
perf_output_put(&handle, comm_event->event_id);
- perf_output_copy(&handle, comm_event->comm,
+ __output_copy(&handle, comm_event->comm,
comm_event->comm_size);
perf_event__output_id_sample(event, &handle, &sample);
perf_event_header__init_id(&mmap_event->event_id.header, &sample, event);
ret = perf_output_begin(&handle, event,
- mmap_event->event_id.header.size, 0, 0);
+ mmap_event->event_id.header.size);
if (ret)
goto out;
mmap_event->event_id.tid = perf_event_tid(event, current);
perf_output_put(&handle, mmap_event->event_id);
- perf_output_copy(&handle, mmap_event->file_name,
+ __output_copy(&handle, mmap_event->file_name,
mmap_event->file_size);
perf_event__output_id_sample(event, &handle, &sample);
if (file) {
/*
- * d_path works from the end of the buffer backwards, so we
+ * d_path works from the end of the rb backwards, so we
* need to add enough zero bytes after the string to handle
* the 64bit alignment we do later.
*/
perf_event_header__init_id(&throttle_event.header, &sample, event);
ret = perf_output_begin(&handle, event,
- throttle_event.header.size, 1, 0);
+ throttle_event.header.size);
if (ret)
return;
* Generic event overflow handling, sampling.
*/
-static int __perf_event_overflow(struct perf_event *event, int nmi,
+static int __perf_event_overflow(struct perf_event *event,
int throttle, struct perf_sample_data *data,
struct pt_regs *regs)
{
if (events && atomic_dec_and_test(&event->event_limit)) {
ret = 1;
event->pending_kill = POLL_HUP;
- if (nmi) {
- event->pending_disable = 1;
- irq_work_queue(&event->pending);
- } else
- perf_event_disable(event);
+ event->pending_disable = 1;
+ irq_work_queue(&event->pending);
}
if (event->overflow_handler)
- event->overflow_handler(event, nmi, data, regs);
+ event->overflow_handler(event, data, regs);
else
- perf_event_output(event, nmi, data, regs);
+ perf_event_output(event, data, regs);
if (event->fasync && event->pending_kill) {
- if (nmi) {
- event->pending_wakeup = 1;
- irq_work_queue(&event->pending);
- } else
- perf_event_wakeup(event);
+ event->pending_wakeup = 1;
+ irq_work_queue(&event->pending);
}
return ret;
}
-int perf_event_overflow(struct perf_event *event, int nmi,
+int perf_event_overflow(struct perf_event *event,
struct perf_sample_data *data,
struct pt_regs *regs)
{
- return __perf_event_overflow(event, nmi, 1, data, regs);
+ return __perf_event_overflow(event, 1, data, regs);
}
/*
}
static void perf_swevent_overflow(struct perf_event *event, u64 overflow,
- int nmi, struct perf_sample_data *data,
+ struct perf_sample_data *data,
struct pt_regs *regs)
{
struct hw_perf_event *hwc = &event->hw;
return;
for (; overflow; overflow--) {
- if (__perf_event_overflow(event, nmi, throttle,
+ if (__perf_event_overflow(event, throttle,
data, regs)) {
/*
* We inhibit the overflow from happening when
}
static void perf_swevent_event(struct perf_event *event, u64 nr,
- int nmi, struct perf_sample_data *data,
+ struct perf_sample_data *data,
struct pt_regs *regs)
{
struct hw_perf_event *hwc = &event->hw;
return;
if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq)
- return perf_swevent_overflow(event, 1, nmi, data, regs);
+ return perf_swevent_overflow(event, 1, data, regs);
if (local64_add_negative(nr, &hwc->period_left))
return;
- perf_swevent_overflow(event, 0, nmi, data, regs);
+ perf_swevent_overflow(event, 0, data, regs);
}
static int perf_exclude_event(struct perf_event *event,
}
static void do_perf_sw_event(enum perf_type_id type, u32 event_id,
- u64 nr, int nmi,
+ u64 nr,
struct perf_sample_data *data,
struct pt_regs *regs)
{
hlist_for_each_entry_rcu(event, node, head, hlist_entry) {
if (perf_swevent_match(event, type, event_id, data, regs))
- perf_swevent_event(event, nr, nmi, data, regs);
+ perf_swevent_event(event, nr, data, regs);
}
end:
rcu_read_unlock();
put_recursion_context(swhash->recursion, rctx);
}
-void __perf_sw_event(u32 event_id, u64 nr, int nmi,
- struct pt_regs *regs, u64 addr)
+void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr)
{
struct perf_sample_data data;
int rctx;
perf_sample_data_init(&data, addr);
- do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, nmi, &data, regs);
+ do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs);
perf_swevent_put_recursion_context(rctx);
preempt_enable_notrace();
hlist_for_each_entry_rcu(event, node, head, hlist_entry) {
if (perf_tp_event_match(event, &data, regs))
- perf_swevent_event(event, count, 1, &data, regs);
+ perf_swevent_event(event, count, &data, regs);
}
perf_swevent_put_recursion_context(rctx);
perf_sample_data_init(&sample, bp->attr.bp_addr);
if (!bp->hw.state && !perf_exclude_event(bp, regs))
- perf_swevent_event(bp, 1, 1, &sample, regs);
+ perf_swevent_event(bp, 1, &sample, regs);
}
#endif
if (regs && !perf_exclude_event(event, regs)) {
if (!(event->attr.exclude_idle && current->pid == 0))
- if (perf_event_overflow(event, 0, &data, regs))
+ if (perf_event_overflow(event, &data, regs))
ret = HRTIMER_NORESTART;
}
struct task_struct *task,
struct perf_event *group_leader,
struct perf_event *parent_event,
- perf_overflow_handler_t overflow_handler)
+ perf_overflow_handler_t overflow_handler,
+ void *context)
{
struct pmu *pmu;
struct perf_event *event;
#endif
}
- if (!overflow_handler && parent_event)
+ if (!overflow_handler && parent_event) {
overflow_handler = parent_event->overflow_handler;
+ context = parent_event->overflow_handler_context;
+ }
event->overflow_handler = overflow_handler;
+ event->overflow_handler_context = context;
if (attr->disabled)
event->state = PERF_EVENT_STATE_OFF;
if (ret)
return -EFAULT;
- /*
- * If the type exists, the corresponding creation will verify
- * the attr->config.
- */
- if (attr->type >= PERF_TYPE_MAX)
- return -EINVAL;
-
if (attr->__reserved_1)
return -EINVAL;
static int
perf_event_set_output(struct perf_event *event, struct perf_event *output_event)
{
- struct perf_buffer *buffer = NULL, *old_buffer = NULL;
+ struct ring_buffer *rb = NULL, *old_rb = NULL;
int ret = -EINVAL;
if (!output_event)
goto out;
/*
- * If its not a per-cpu buffer, it must be the same task.
+ * If its not a per-cpu rb, it must be the same task.
*/
if (output_event->cpu == -1 && output_event->ctx != event->ctx)
goto out;
goto unlock;
if (output_event) {
- /* get the buffer we want to redirect to */
- buffer = perf_buffer_get(output_event);
- if (!buffer)
+ /* get the rb we want to redirect to */
+ rb = ring_buffer_get(output_event);
+ if (!rb)
goto unlock;
}
- old_buffer = event->buffer;
- rcu_assign_pointer(event->buffer, buffer);
+ old_rb = event->rb;
+ rcu_assign_pointer(event->rb, rb);
ret = 0;
unlock:
mutex_unlock(&event->mmap_mutex);
- if (old_buffer)
- perf_buffer_put(old_buffer);
+ if (old_rb)
+ ring_buffer_put(old_rb);
out:
return ret;
}
}
}
- event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, NULL);
+ event = perf_event_alloc(&attr, cpu, task, group_leader, NULL,
+ NULL, NULL);
if (IS_ERR(event)) {
err = PTR_ERR(event);
goto err_task;
struct perf_event *
perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
struct task_struct *task,
- perf_overflow_handler_t overflow_handler)
+ perf_overflow_handler_t overflow_handler,
+ void *context)
{
struct perf_event_context *ctx;
struct perf_event *event;
* Get the target context (task or percpu):
*/
- event = perf_event_alloc(attr, cpu, task, NULL, NULL, overflow_handler);
+ event = perf_event_alloc(attr, cpu, task, NULL, NULL,
+ overflow_handler, context);
if (IS_ERR(event)) {
err = PTR_ERR(event);
goto err;
* incremented the context's refcount before we do put_ctx below.
*/
raw_spin_lock(&child_ctx->lock);
- task_ctx_sched_out(child_ctx, EVENT_ALL);
+ task_ctx_sched_out(child_ctx);
child->perf_event_ctxp[ctxn] = NULL;
/*
* If this context is a clone; unclone it so it can't get
parent_event->cpu,
child,
group_leader, parent_event,
- NULL);
+ NULL, NULL);
if (IS_ERR(child_event))
return child_event;
get_ctx(child_ctx);
child_event->ctx = child_ctx;
child_event->overflow_handler = parent_event->overflow_handler;
+ child_event->overflow_handler_context
+ = parent_event->overflow_handler_context;
/*
* Precalculate sample_data sizes
return 0;
}
-static void perf_cgroup_move(struct task_struct *task)
+static void
+perf_cgroup_attach_task(struct cgroup *cgrp, struct task_struct *task)
{
task_function_call(task, __perf_cgroup_move, task);
}
-static void perf_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
- struct cgroup *old_cgrp, struct task_struct *task,
- bool threadgroup)
-{
- perf_cgroup_move(task);
- if (threadgroup) {
- struct task_struct *c;
- rcu_read_lock();
- list_for_each_entry_rcu(c, &task->thread_group, thread_group) {
- perf_cgroup_move(c);
- }
- rcu_read_unlock();
- }
-}
-
static void perf_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp,
struct cgroup *old_cgrp, struct task_struct *task)
{
if (!(task->flags & PF_EXITING))
return;
- perf_cgroup_move(task);
+ perf_cgroup_attach_task(cgrp, task);
}
struct cgroup_subsys perf_subsys = {
.create = perf_cgroup_create,
.destroy = perf_cgroup_destroy,
.exit = perf_cgroup_exit,
- .attach = perf_cgroup_attach,
+ .attach_task = perf_cgroup_attach_task,
};
#endif /* CONFIG_CGROUP_PERF */
Code Review / linux-2.6.git / blobdiff