#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"
*/
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;
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)
{
#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)
{
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)) {
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);
}
}
* Those places that change perf_event::ctx will hold both
* perf_event_ctx::mutex of the 'old' and 'new' ctx value.
*
- * Lock ordering is by mutex address. There is one other site where
- * perf_event_context::mutex nests and that is put_event(). But remember that
- * that is a parent<->child context relation, and migration does not affect
- * children, therefore these two orderings should not interact.
+ * Lock ordering is by mutex address. There are two other sites where
+ * perf_event_context::mutex nests and those are:
+ *
+ * - perf_event_exit_task_context() [ child , 0 ]
+ * __perf_event_exit_task()
+ * sync_child_event()
+ * put_event() [ parent, 1 ]
+ *
+ * - perf_event_init_context() [ parent, 0 ]
+ * inherit_task_group()
+ * inherit_group()
+ * inherit_event()
+ * perf_event_alloc()
+ * perf_init_event()
+ * perf_try_init_event() [ child , 1 ]
+ *
+ * While it appears there is an obvious deadlock here -- the parent and child
+ * nesting levels are inverted between the two. This is in fact safe because
+ * life-time rules separate them. That is an exiting task cannot fork, and a
+ * spawning task cannot (yet) exit.
+ *
+ * But remember that that these are parent<->child context relations, and
+ * migration does not affect children, therefore these two orderings should not
+ * interact.
*
* The change in perf_event::ctx does not affect children (as claimed above)
* because the sys_perf_event_open() case will install a new event and break
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)
cpuctx->cgrp = NULL;
}
- if (has_branch_stack(event))
- ctx->nr_branch_stack--;
-
ctx->nr_events--;
if (event->attr.inherit_stat)
ctx->nr_stat--;
#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,
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;
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++)
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);
}
}
+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)++)
{
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);
perf_ctx_unlock(cpuctx, 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.
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)
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)
* 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: */
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)
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);
/*
}
}
+ 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)
{
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);
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));
}
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) {
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);
}
}
}
-/*
- * Called when the last reference to the file is gone.
- */
static void put_event(struct perf_event *event)
{
struct perf_event_context *ctx;
}
EXPORT_SYMBOL_GPL(perf_event_release_kernel);
+/*
+ * Called when the last reference to the file is gone.
+ */
static int perf_release(struct inode *inode, struct file *file)
{
put_event(file->private_data);
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)
{
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;
}
/* 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();
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;
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;
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);
}
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))
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,
};
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;
/*
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
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);
}
user_extra = nr_pages + 1;
+
+accounting:
user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10);
/*
user_locked = atomic_long_read(&user->locked_vm) + user_extra;
- extra = 0;
if (user_locked > user_lock_limit)
extra = user_locked - user_lock_limit;
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);
/*
}
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);
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);
/* .ppid */
/* .tid */
/* .ptid */
- .time = perf_clock(),
+ /* .time */
},
};
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
*/
.misc = 0,
.size = sizeof(throttle_event),
},
- .time = perf_clock(),
+ .time = perf_event_clock(event),
.id = primary_event_id(event),
.stream_id = event->id,
};
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.
*/
}
hlist_add_head_rcu(&event->hlist_entry, head);
+ perf_event_update_userpage(event);
return 0;
}
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,
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)
{
}
+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
{
if (flags & PERF_EF_START)
cpu_clock_event_start(event, flags);
+ perf_event_update_userpage(event);
return 0;
}
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,
{
if (flags & PERF_EF_START)
task_clock_event_start(event, flags);
+ perf_event_update_userpage(event);
return 0;
}
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,
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);
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) {
+ /*
+ * This ctx->mutex can nest when we're called through
+ * inheritance. See the perf_event_ctx_lock_nested() comment.
+ */
+ ctx = perf_event_ctx_lock_nested(event->group_leader,
+ SINGLE_DEPTH_NESTING);
+ 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);
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));
}
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;
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;
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;
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);
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() */
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
*
int move_group = 0;
int err;
int f_flags = O_RDWR;
+ int cgroup_fd = -1;
/* for future expandability... */
if (flags & ~PERF_FLAG_ALL)
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;
*/
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)) {
/*
* 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;
*/
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:
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);
*/
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;
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;
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);
parent_event->cpu,
child,
group_leader, parent_event,
- NULL, NULL);
+ NULL, NULL, -1);
if (IS_ERR(child_event))
return child_event;
projects / linux-2.6-microblaze.git / blobdiff