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-rw-r--r--kernel/events/core.c663
1 files changed, 340 insertions, 323 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 426c2ffba16d..16beab4767e1 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -209,7 +209,7 @@ static int event_function(void *info)
struct perf_event_context *task_ctx = cpuctx->task_ctx;
int ret = 0;
- WARN_ON_ONCE(!irqs_disabled());
+ lockdep_assert_irqs_disabled();
perf_ctx_lock(cpuctx, task_ctx);
/*
@@ -306,7 +306,7 @@ static void event_function_local(struct perf_event *event, event_f func, void *d
struct task_struct *task = READ_ONCE(ctx->task);
struct perf_event_context *task_ctx = NULL;
- WARN_ON_ONCE(!irqs_disabled());
+ lockdep_assert_irqs_disabled();
if (task) {
if (task == TASK_TOMBSTONE)
@@ -582,6 +582,88 @@ static inline u64 perf_event_clock(struct perf_event *event)
return event->clock();
}
+/*
+ * State based event timekeeping...
+ *
+ * The basic idea is to use event->state to determine which (if any) time
+ * fields to increment with the current delta. This means we only need to
+ * update timestamps when we change state or when they are explicitly requested
+ * (read).
+ *
+ * Event groups make things a little more complicated, but not terribly so. The
+ * rules for a group are that if the group leader is OFF the entire group is
+ * OFF, irrespecive of what the group member states are. This results in
+ * __perf_effective_state().
+ *
+ * A futher ramification is that when a group leader flips between OFF and
+ * !OFF, we need to update all group member times.
+ *
+ *
+ * NOTE: perf_event_time() is based on the (cgroup) context time, and thus we
+ * need to make sure the relevant context time is updated before we try and
+ * update our timestamps.
+ */
+
+static __always_inline enum perf_event_state
+__perf_effective_state(struct perf_event *event)
+{
+ struct perf_event *leader = event->group_leader;
+
+ if (leader->state <= PERF_EVENT_STATE_OFF)
+ return leader->state;
+
+ return event->state;
+}
+
+static __always_inline void
+__perf_update_times(struct perf_event *event, u64 now, u64 *enabled, u64 *running)
+{
+ enum perf_event_state state = __perf_effective_state(event);
+ u64 delta = now - event->tstamp;
+
+ *enabled = event->total_time_enabled;
+ if (state >= PERF_EVENT_STATE_INACTIVE)
+ *enabled += delta;
+
+ *running = event->total_time_running;
+ if (state >= PERF_EVENT_STATE_ACTIVE)
+ *running += delta;
+}
+
+static void perf_event_update_time(struct perf_event *event)
+{
+ u64 now = perf_event_time(event);
+
+ __perf_update_times(event, now, &event->total_time_enabled,
+ &event->total_time_running);
+ event->tstamp = now;
+}
+
+static void perf_event_update_sibling_time(struct perf_event *leader)
+{
+ struct perf_event *sibling;
+
+ list_for_each_entry(sibling, &leader->sibling_list, group_entry)
+ perf_event_update_time(sibling);
+}
+
+static void
+perf_event_set_state(struct perf_event *event, enum perf_event_state state)
+{
+ if (event->state == state)
+ return;
+
+ perf_event_update_time(event);
+ /*
+ * If a group leader gets enabled/disabled all its siblings
+ * are affected too.
+ */
+ if ((event->state < 0) ^ (state < 0))
+ perf_event_update_sibling_time(event);
+
+ WRITE_ONCE(event->state, state);
+}
+
#ifdef CONFIG_CGROUP_PERF
static inline bool
@@ -662,7 +744,7 @@ static inline void update_cgrp_time_from_event(struct perf_event *event)
/*
* Do not update time when cgroup is not active
*/
- if (cgrp == event->cgrp)
+ if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup))
__update_cgrp_time(event->cgrp);
}
@@ -841,40 +923,6 @@ perf_cgroup_set_shadow_time(struct perf_event *event, u64 now)
event->shadow_ctx_time = now - t->timestamp;
}
-static inline void
-perf_cgroup_defer_enabled(struct perf_event *event)
-{
- /*
- * when the current task's perf cgroup does not match
- * the event's, we need to remember to call the
- * perf_mark_enable() function the first time a task with
- * a matching perf cgroup is scheduled in.
- */
- if (is_cgroup_event(event) && !perf_cgroup_match(event))
- event->cgrp_defer_enabled = 1;
-}
-
-static inline void
-perf_cgroup_mark_enabled(struct perf_event *event,
- struct perf_event_context *ctx)
-{
- struct perf_event *sub;
- u64 tstamp = perf_event_time(event);
-
- if (!event->cgrp_defer_enabled)
- return;
-
- event->cgrp_defer_enabled = 0;
-
- event->tstamp_enabled = tstamp - event->total_time_enabled;
- list_for_each_entry(sub, &event->sibling_list, group_entry) {
- if (sub->state >= PERF_EVENT_STATE_INACTIVE) {
- sub->tstamp_enabled = tstamp - sub->total_time_enabled;
- sub->cgrp_defer_enabled = 0;
- }
- }
-}
-
/*
* Update cpuctx->cgrp so that it is set when first cgroup event is added and
* cleared when last cgroup event is removed.
@@ -901,9 +949,11 @@ list_update_cgroup_event(struct perf_event *event,
cpuctx_entry = &cpuctx->cgrp_cpuctx_entry;
/* cpuctx->cgrp is NULL unless a cgroup event is active in this CPU .*/
if (add) {
+ struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx);
+
list_add(cpuctx_entry, this_cpu_ptr(&cgrp_cpuctx_list));
- if (perf_cgroup_from_task(current, ctx) == event->cgrp)
- cpuctx->cgrp = event->cgrp;
+ if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup))
+ cpuctx->cgrp = cgrp;
} else {
list_del(cpuctx_entry);
cpuctx->cgrp = NULL;
@@ -973,17 +1023,6 @@ static inline u64 perf_cgroup_event_time(struct perf_event *event)
}
static inline void
-perf_cgroup_defer_enabled(struct perf_event *event)
-{
-}
-
-static inline void
-perf_cgroup_mark_enabled(struct perf_event *event,
- struct perf_event_context *ctx)
-{
-}
-
-static inline void
list_update_cgroup_event(struct perf_event *event,
struct perf_event_context *ctx, bool add)
{
@@ -1004,7 +1043,7 @@ static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr)
struct perf_cpu_context *cpuctx;
int rotations = 0;
- WARN_ON(!irqs_disabled());
+ lockdep_assert_irqs_disabled();
cpuctx = container_of(hr, struct perf_cpu_context, hrtimer);
rotations = perf_rotate_context(cpuctx);
@@ -1091,7 +1130,7 @@ static void perf_event_ctx_activate(struct perf_event_context *ctx)
{
struct list_head *head = this_cpu_ptr(&active_ctx_list);
- WARN_ON(!irqs_disabled());
+ lockdep_assert_irqs_disabled();
WARN_ON(!list_empty(&ctx->active_ctx_list));
@@ -1100,7 +1139,7 @@ static void perf_event_ctx_activate(struct perf_event_context *ctx)
static void perf_event_ctx_deactivate(struct perf_event_context *ctx)
{
- WARN_ON(!irqs_disabled());
+ lockdep_assert_irqs_disabled();
WARN_ON(list_empty(&ctx->active_ctx_list));
@@ -1200,7 +1239,7 @@ perf_event_ctx_lock_nested(struct perf_event *event, int nesting)
again:
rcu_read_lock();
- ctx = ACCESS_ONCE(event->ctx);
+ ctx = READ_ONCE(event->ctx);
if (!atomic_inc_not_zero(&ctx->refcount)) {
rcu_read_unlock();
goto again;
@@ -1249,26 +1288,31 @@ unclone_ctx(struct perf_event_context *ctx)
return parent_ctx;
}
-static u32 perf_event_pid(struct perf_event *event, struct task_struct *p)
+static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p,
+ enum pid_type type)
{
+ u32 nr;
/*
* only top level events have the pid namespace they were created in
*/
if (event->parent)
event = event->parent;
- return task_tgid_nr_ns(p, event->ns);
+ nr = __task_pid_nr_ns(p, type, event->ns);
+ /* avoid -1 if it is idle thread or runs in another ns */
+ if (!nr && !pid_alive(p))
+ nr = -1;
+ return nr;
+}
+
+static u32 perf_event_pid(struct perf_event *event, struct task_struct *p)
+{
+ return perf_event_pid_type(event, p, __PIDTYPE_TGID);
}
static u32 perf_event_tid(struct perf_event *event, struct task_struct *p)
{
- /*
- * only top level events have the pid namespace they were created in
- */
- if (event->parent)
- event = event->parent;
-
- return task_pid_nr_ns(p, event->ns);
+ return perf_event_pid_type(event, p, PIDTYPE_PID);
}
/*
@@ -1391,60 +1435,6 @@ static u64 perf_event_time(struct perf_event *event)
return ctx ? ctx->time : 0;
}
-/*
- * Update the total_time_enabled and total_time_running fields for a event.
- */
-static void update_event_times(struct perf_event *event)
-{
- struct perf_event_context *ctx = event->ctx;
- u64 run_end;
-
- lockdep_assert_held(&ctx->lock);
-
- if (event->state < PERF_EVENT_STATE_INACTIVE ||
- event->group_leader->state < PERF_EVENT_STATE_INACTIVE)
- return;
-
- /*
- * in cgroup mode, time_enabled represents
- * the time the event was enabled AND active
- * tasks were in the monitored cgroup. This is
- * independent of the activity of the context as
- * there may be a mix of cgroup and non-cgroup events.
- *
- * That is why we treat cgroup events differently
- * here.
- */
- if (is_cgroup_event(event))
- run_end = perf_cgroup_event_time(event);
- else if (ctx->is_active)
- run_end = ctx->time;
- else
- run_end = event->tstamp_stopped;
-
- event->total_time_enabled = run_end - event->tstamp_enabled;
-
- if (event->state == PERF_EVENT_STATE_INACTIVE)
- run_end = event->tstamp_stopped;
- else
- run_end = perf_event_time(event);
-
- event->total_time_running = run_end - event->tstamp_running;
-
-}
-
-/*
- * Update total_time_enabled and total_time_running for all events in a group.
- */
-static void update_group_times(struct perf_event *leader)
-{
- struct perf_event *event;
-
- update_event_times(leader);
- list_for_each_entry(event, &leader->sibling_list, group_entry)
- update_event_times(event);
-}
-
static enum event_type_t get_event_type(struct perf_event *event)
{
struct perf_event_context *ctx = event->ctx;
@@ -1487,6 +1477,8 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx)
WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT);
event->attach_state |= PERF_ATTACH_CONTEXT;
+ event->tstamp = perf_event_time(event);
+
/*
* If we're a stand alone event or group leader, we go to the context
* list, group events are kept attached to the group so that
@@ -1570,6 +1562,9 @@ static void __perf_event_header_size(struct perf_event *event, u64 sample_type)
if (sample_type & PERF_SAMPLE_TRANSACTION)
size += sizeof(data->txn);
+ if (sample_type & PERF_SAMPLE_PHYS_ADDR)
+ size += sizeof(data->phys_addr);
+
event->header_size = size;
}
@@ -1691,8 +1686,6 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx)
if (event->group_leader == event)
list_del_init(&event->group_entry);
- update_group_times(event);
-
/*
* If event was in error state, then keep it
* that way, otherwise bogus counts will be
@@ -1701,7 +1694,7 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx)
* of the event
*/
if (event->state > PERF_EVENT_STATE_OFF)
- event->state = PERF_EVENT_STATE_OFF;
+ perf_event_set_state(event, PERF_EVENT_STATE_OFF);
ctx->generation++;
}
@@ -1800,38 +1793,24 @@ event_sched_out(struct perf_event *event,
struct perf_cpu_context *cpuctx,
struct perf_event_context *ctx)
{
- u64 tstamp = perf_event_time(event);
- u64 delta;
+ enum perf_event_state state = PERF_EVENT_STATE_INACTIVE;
WARN_ON_ONCE(event->ctx != ctx);
lockdep_assert_held(&ctx->lock);
- /*
- * An event which could not be activated because of
- * filter mismatch still needs to have its timings
- * maintained, otherwise bogus information is return
- * via read() for time_enabled, time_running:
- */
- if (event->state == PERF_EVENT_STATE_INACTIVE &&
- !event_filter_match(event)) {
- delta = tstamp - event->tstamp_stopped;
- event->tstamp_running += delta;
- event->tstamp_stopped = tstamp;
- }
-
if (event->state != PERF_EVENT_STATE_ACTIVE)
return;
perf_pmu_disable(event->pmu);
- event->tstamp_stopped = tstamp;
event->pmu->del(event, 0);
event->oncpu = -1;
- event->state = PERF_EVENT_STATE_INACTIVE;
+
if (event->pending_disable) {
event->pending_disable = 0;
- event->state = PERF_EVENT_STATE_OFF;
+ state = PERF_EVENT_STATE_OFF;
}
+ perf_event_set_state(event, state);
if (!is_software_event(event))
cpuctx->active_oncpu--;
@@ -1851,7 +1830,9 @@ group_sched_out(struct perf_event *group_event,
struct perf_event_context *ctx)
{
struct perf_event *event;
- int state = group_event->state;
+
+ if (group_event->state != PERF_EVENT_STATE_ACTIVE)
+ return;
perf_pmu_disable(ctx->pmu);
@@ -1865,7 +1846,7 @@ group_sched_out(struct perf_event *group_event,
perf_pmu_enable(ctx->pmu);
- if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive)
+ if (group_event->attr.exclusive)
cpuctx->exclusive = 0;
}
@@ -1885,6 +1866,11 @@ __perf_remove_from_context(struct perf_event *event,
{
unsigned long flags = (unsigned long)info;
+ if (ctx->is_active & EVENT_TIME) {
+ update_context_time(ctx);
+ update_cgrp_time_from_cpuctx(cpuctx);
+ }
+
event_sched_out(event, cpuctx, ctx);
if (flags & DETACH_GROUP)
perf_group_detach(event);
@@ -1947,14 +1933,17 @@ static void __perf_event_disable(struct perf_event *event,
if (event->state < PERF_EVENT_STATE_INACTIVE)
return;
- update_context_time(ctx);
- update_cgrp_time_from_event(event);
- update_group_times(event);
+ if (ctx->is_active & EVENT_TIME) {
+ update_context_time(ctx);
+ update_cgrp_time_from_event(event);
+ }
+
if (event == event->group_leader)
group_sched_out(event, cpuctx, ctx);
else
event_sched_out(event, cpuctx, ctx);
- event->state = PERF_EVENT_STATE_OFF;
+
+ perf_event_set_state(event, PERF_EVENT_STATE_OFF);
}
/*
@@ -2011,8 +2000,7 @@ void perf_event_disable_inatomic(struct perf_event *event)
}
static void perf_set_shadow_time(struct perf_event *event,
- struct perf_event_context *ctx,
- u64 tstamp)
+ struct perf_event_context *ctx)
{
/*
* use the correct time source for the time snapshot
@@ -2040,9 +2028,9 @@ static void perf_set_shadow_time(struct perf_event *event,
* is cleaner and simpler to understand.
*/
if (is_cgroup_event(event))
- perf_cgroup_set_shadow_time(event, tstamp);
+ perf_cgroup_set_shadow_time(event, event->tstamp);
else
- event->shadow_ctx_time = tstamp - ctx->timestamp;
+ event->shadow_ctx_time = event->tstamp - ctx->timestamp;
}
#define MAX_INTERRUPTS (~0ULL)
@@ -2055,7 +2043,6 @@ event_sched_in(struct perf_event *event,
struct perf_cpu_context *cpuctx,
struct perf_event_context *ctx)
{
- u64 tstamp = perf_event_time(event);
int ret = 0;
lockdep_assert_held(&ctx->lock);
@@ -2065,11 +2052,12 @@ event_sched_in(struct perf_event *event,
WRITE_ONCE(event->oncpu, smp_processor_id());
/*
- * Order event::oncpu write to happen before the ACTIVE state
- * is visible.
+ * Order event::oncpu write to happen before the ACTIVE state is
+ * visible. This allows perf_event_{stop,read}() to observe the correct
+ * ->oncpu if it sees ACTIVE.
*/
smp_wmb();
- WRITE_ONCE(event->state, PERF_EVENT_STATE_ACTIVE);
+ perf_event_set_state(event, PERF_EVENT_STATE_ACTIVE);
/*
* Unthrottle events, since we scheduled we might have missed several
@@ -2081,26 +2069,19 @@ event_sched_in(struct perf_event *event,
event->hw.interrupts = 0;
}
- /*
- * The new state must be visible before we turn it on in the hardware:
- */
- smp_wmb();
-
perf_pmu_disable(event->pmu);
- perf_set_shadow_time(event, ctx, tstamp);
+ perf_set_shadow_time(event, ctx);
perf_log_itrace_start(event);
if (event->pmu->add(event, PERF_EF_START)) {
- event->state = PERF_EVENT_STATE_INACTIVE;
+ perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE);
event->oncpu = -1;
ret = -EAGAIN;
goto out;
}
- event->tstamp_running += tstamp - event->tstamp_stopped;
-
if (!is_software_event(event))
cpuctx->active_oncpu++;
if (!ctx->nr_active++)
@@ -2124,8 +2105,6 @@ group_sched_in(struct perf_event *group_event,
{
struct perf_event *event, *partial_group = NULL;
struct pmu *pmu = ctx->pmu;
- u64 now = ctx->time;
- bool simulate = false;
if (group_event->state == PERF_EVENT_STATE_OFF)
return 0;
@@ -2155,27 +2134,13 @@ group_error:
/*
* Groups can be scheduled in as one unit only, so undo any
* partial group before returning:
- * The events up to the failed event are scheduled out normally,
- * tstamp_stopped will be updated.
- *
- * The failed events and the remaining siblings need to have
- * their timings updated as if they had gone thru event_sched_in()
- * and event_sched_out(). This is required to get consistent timings
- * across the group. This also takes care of the case where the group
- * could never be scheduled by ensuring tstamp_stopped is set to mark
- * the time the event was actually stopped, such that time delta
- * calculation in update_event_times() is correct.
+ * The events up to the failed event are scheduled out normally.
*/
list_for_each_entry(event, &group_event->sibling_list, group_entry) {
if (event == partial_group)
- simulate = true;
+ break;
- if (simulate) {
- event->tstamp_running += now - event->tstamp_stopped;
- event->tstamp_stopped = now;
- } else {
- event_sched_out(event, cpuctx, ctx);
- }
+ event_sched_out(event, cpuctx, ctx);
}
event_sched_out(group_event, cpuctx, ctx);
@@ -2220,13 +2185,8 @@ static int group_can_go_on(struct perf_event *event,
static void add_event_to_ctx(struct perf_event *event,
struct perf_event_context *ctx)
{
- u64 tstamp = perf_event_time(event);
-
list_add_event(event, ctx);
perf_group_attach(event);
- event->tstamp_enabled = tstamp;
- event->tstamp_running = tstamp;
- event->tstamp_stopped = tstamp;
}
static void ctx_sched_out(struct perf_event_context *ctx,
@@ -2458,27 +2418,6 @@ again:
}
/*
- * Put a event into inactive state and update time fields.
- * Enabling the leader of a group effectively enables all
- * the group members that aren't explicitly disabled, so we
- * have to update their ->tstamp_enabled also.
- * Note: this works for group members as well as group leaders
- * since the non-leader members' sibling_lists will be empty.
- */
-static void __perf_event_mark_enabled(struct perf_event *event)
-{
- struct perf_event *sub;
- u64 tstamp = perf_event_time(event);
-
- event->state = PERF_EVENT_STATE_INACTIVE;
- event->tstamp_enabled = tstamp - event->total_time_enabled;
- list_for_each_entry(sub, &event->sibling_list, group_entry) {
- if (sub->state >= PERF_EVENT_STATE_INACTIVE)
- sub->tstamp_enabled = tstamp - sub->total_time_enabled;
- }
-}
-
-/*
* Cross CPU call to enable a performance event
*/
static void __perf_event_enable(struct perf_event *event,
@@ -2496,14 +2435,12 @@ static void __perf_event_enable(struct perf_event *event,
if (ctx->is_active)
ctx_sched_out(ctx, cpuctx, EVENT_TIME);
- __perf_event_mark_enabled(event);
+ perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE);
if (!ctx->is_active)
return;
if (!event_filter_match(event)) {
- if (is_cgroup_event(event))
- perf_cgroup_defer_enabled(event);
ctx_sched_in(ctx, cpuctx, EVENT_TIME, current);
return;
}
@@ -2823,18 +2760,10 @@ static void __perf_event_sync_stat(struct perf_event *event,
* we know the event must be on the current CPU, therefore we
* don't need to use it.
*/
- switch (event->state) {
- case PERF_EVENT_STATE_ACTIVE:
+ if (event->state == PERF_EVENT_STATE_ACTIVE)
event->pmu->read(event);
- /* fall-through */
- case PERF_EVENT_STATE_INACTIVE:
- update_event_times(event);
- break;
-
- default:
- break;
- }
+ perf_event_update_time(event);
/*
* In order to keep per-task stats reliable we need to flip the event
@@ -3071,10 +3000,6 @@ ctx_pinned_sched_in(struct perf_event_context *ctx,
if (!event_filter_match(event))
continue;
- /* may need to reset tstamp_enabled */
- if (is_cgroup_event(event))
- perf_cgroup_mark_enabled(event, ctx);
-
if (group_can_go_on(event, cpuctx, 1))
group_sched_in(event, cpuctx, ctx);
@@ -3082,10 +3007,8 @@ ctx_pinned_sched_in(struct perf_event_context *ctx,
* If this pinned group hasn't been scheduled,
* put it in error state.
*/
- if (event->state == PERF_EVENT_STATE_INACTIVE) {
- update_group_times(event);
- event->state = PERF_EVENT_STATE_ERROR;
- }
+ if (event->state == PERF_EVENT_STATE_INACTIVE)
+ perf_event_set_state(event, PERF_EVENT_STATE_ERROR);
}
}
@@ -3107,10 +3030,6 @@ ctx_flexible_sched_in(struct perf_event_context *ctx,
if (!event_filter_match(event))
continue;
- /* may need to reset tstamp_enabled */
- if (is_cgroup_event(event))
- perf_cgroup_mark_enabled(event, ctx);
-
if (group_can_go_on(event, cpuctx, can_add_hw)) {
if (group_sched_in(event, cpuctx, ctx))
can_add_hw = 0;
@@ -3180,6 +3099,13 @@ static void perf_event_context_sched_in(struct perf_event_context *ctx,
return;
perf_ctx_lock(cpuctx, ctx);
+ /*
+ * We must check ctx->nr_events while holding ctx->lock, such
+ * that we serialize against perf_install_in_context().
+ */
+ if (!ctx->nr_events)
+ goto unlock;
+
perf_pmu_disable(ctx->pmu);
/*
* We want to keep the following priority order:
@@ -3193,6 +3119,8 @@ static void perf_event_context_sched_in(struct perf_event_context *ctx,
cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
perf_event_sched_in(cpuctx, ctx, task);
perf_pmu_enable(ctx->pmu);
+
+unlock:
perf_ctx_unlock(cpuctx, ctx);
}
@@ -3473,7 +3401,7 @@ void perf_event_task_tick(void)
struct perf_event_context *ctx, *tmp;
int throttled;
- WARN_ON(!irqs_disabled());
+ lockdep_assert_irqs_disabled();
__this_cpu_inc(perf_throttled_seq);
throttled = __this_cpu_xchg(perf_throttled_count, 0);
@@ -3493,7 +3421,7 @@ static int event_enable_on_exec(struct perf_event *event,
if (event->state >= PERF_EVENT_STATE_INACTIVE)
return 0;
- __perf_event_mark_enabled(event);
+ perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE);
return 1;
}
@@ -3587,12 +3515,15 @@ static void __perf_event_read(void *info)
return;
raw_spin_lock(&ctx->lock);
- if (ctx->is_active) {
+ if (ctx->is_active & EVENT_TIME) {
update_context_time(ctx);
update_cgrp_time_from_event(event);
}
- update_event_times(event);
+ perf_event_update_time(event);
+ if (data->group)
+ perf_event_update_sibling_time(event);
+
if (event->state != PERF_EVENT_STATE_ACTIVE)
goto unlock;
@@ -3607,7 +3538,6 @@ static void __perf_event_read(void *info)
pmu->read(event);
list_for_each_entry(sub, &event->sibling_list, group_entry) {
- update_event_times(sub);
if (sub->state == PERF_EVENT_STATE_ACTIVE) {
/*
* Use sibling's PMU rather than @event's since
@@ -3625,10 +3555,7 @@ unlock:
static inline u64 perf_event_count(struct perf_event *event)
{
- if (event->pmu->count)
- return event->pmu->count(event);
-
- return __perf_event_count(event);
+ return local64_read(&event->count) + atomic64_read(&event->child_count);
}
/*
@@ -3639,7 +3566,8 @@ static inline u64 perf_event_count(struct perf_event *event)
* will not be local and we cannot read them atomically
* - must not have a pmu::count method
*/
-int perf_event_read_local(struct perf_event *event, u64 *value)
+int perf_event_read_local(struct perf_event *event, u64 *value,
+ u64 *enabled, u64 *running)
{
unsigned long flags;
int ret = 0;
@@ -3659,15 +3587,6 @@ int perf_event_read_local(struct perf_event *event, u64 *value)
goto out;
}
- /*
- * It must not have a pmu::count method, those are not
- * NMI safe.
- */
- if (event->pmu->count) {
- ret = -EOPNOTSUPP;
- goto out;
- }
-
/* If this is a per-task event, it must be for current */
if ((event->attach_state & PERF_ATTACH_TASK) &&
event->hw.target != current) {
@@ -3691,6 +3610,16 @@ int perf_event_read_local(struct perf_event *event, u64 *value)
event->pmu->read(event);
*value = local64_read(&event->count);
+ if (enabled || running) {
+ u64 now = event->shadow_ctx_time + perf_clock();
+ u64 __enabled, __running;
+
+ __perf_update_times(event, now, &__enabled, &__running);
+ if (enabled)
+ *enabled = __enabled;
+ if (running)
+ *running = __running;
+ }
out:
local_irq_restore(flags);
@@ -3699,23 +3628,35 @@ out:
static int perf_event_read(struct perf_event *event, bool group)
{
+ enum perf_event_state state = READ_ONCE(event->state);
int event_cpu, ret = 0;
/*
* If event is enabled and currently active on a CPU, update the
* value in the event structure:
*/
- if (event->state == PERF_EVENT_STATE_ACTIVE) {
- struct perf_read_data data = {
- .event = event,
- .group = group,
- .ret = 0,
- };
+again:
+ if (state == PERF_EVENT_STATE_ACTIVE) {
+ struct perf_read_data data;
+
+ /*
+ * Orders the ->state and ->oncpu loads such that if we see
+ * ACTIVE we must also see the right ->oncpu.
+ *
+ * Matches the smp_wmb() from event_sched_in().
+ */
+ smp_rmb();
event_cpu = READ_ONCE(event->oncpu);
if ((unsigned)event_cpu >= nr_cpu_ids)
return 0;
+ data = (struct perf_read_data){
+ .event = event,
+ .group = group,
+ .ret = 0,
+ };
+
preempt_disable();
event_cpu = __perf_event_read_cpu(event, event_cpu);
@@ -3732,24 +3673,30 @@ static int perf_event_read(struct perf_event *event, bool group)
(void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1);
preempt_enable();
ret = data.ret;
- } else if (event->state == PERF_EVENT_STATE_INACTIVE) {
+
+ } else if (state == PERF_EVENT_STATE_INACTIVE) {
struct perf_event_context *ctx = event->ctx;
unsigned long flags;
raw_spin_lock_irqsave(&ctx->lock, flags);
+ state = event->state;
+ if (state != PERF_EVENT_STATE_INACTIVE) {
+ raw_spin_unlock_irqrestore(&ctx->lock, flags);
+ goto again;
+ }
+
/*
- * may read while context is not active
- * (e.g., thread is blocked), in that case
- * we cannot update context time
+ * May read while context is not active (e.g., thread is
+ * blocked), in that case we cannot update context time
*/
- if (ctx->is_active) {
+ if (ctx->is_active & EVENT_TIME) {
update_context_time(ctx);
update_cgrp_time_from_event(event);
}
+
+ perf_event_update_time(event);
if (group)
- update_group_times(event);
- else
- update_event_times(event);
+ perf_event_update_sibling_time(event);
raw_spin_unlock_irqrestore(&ctx->lock, flags);
}
@@ -4195,7 +4142,7 @@ static void perf_remove_from_owner(struct perf_event *event)
* indeed free this event, otherwise we need to serialize on
* owner->perf_event_mutex.
*/
- owner = lockless_dereference(event->owner);
+ owner = READ_ONCE(event->owner);
if (owner) {
/*
* Since delayed_put_task_struct() also drops the last
@@ -4292,7 +4239,7 @@ again:
* Cannot change, child events are not migrated, see the
* comment with perf_event_ctx_lock_nested().
*/
- ctx = lockless_dereference(child->ctx);
+ ctx = READ_ONCE(child->ctx);
/*
* Since child_mutex nests inside ctx::mutex, we must jump
* through hoops. We start by grabbing a reference on the ctx.
@@ -4352,7 +4299,7 @@ static int perf_release(struct inode *inode, struct file *file)
return 0;
}
-u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running)
+static u64 __perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running)
{
struct perf_event *child;
u64 total = 0;
@@ -4380,6 +4327,18 @@ u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running)
return total;
}
+
+u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running)
+{
+ struct perf_event_context *ctx;
+ u64 count;
+
+ ctx = perf_event_ctx_lock(event);
+ count = __perf_event_read_value(event, enabled, running);
+ perf_event_ctx_unlock(event, ctx);
+
+ return count;
+}
EXPORT_SYMBOL_GPL(perf_event_read_value);
static int __perf_read_group_add(struct perf_event *leader,
@@ -4395,6 +4354,8 @@ static int __perf_read_group_add(struct perf_event *leader,
if (ret)
return ret;
+ raw_spin_lock_irqsave(&ctx->lock, flags);
+
/*
* Since we co-schedule groups, {enabled,running} times of siblings
* will be identical to those of the leader, so we only publish one
@@ -4417,8 +4378,6 @@ static int __perf_read_group_add(struct perf_event *leader,
if (read_format & PERF_FORMAT_ID)
values[n++] = primary_event_id(leader);
- raw_spin_lock_irqsave(&ctx->lock, flags);
-
list_for_each_entry(sub, &leader->sibling_list, group_entry) {
values[n++] += perf_event_count(sub);
if (read_format & PERF_FORMAT_ID)
@@ -4482,7 +4441,7 @@ static int perf_read_one(struct perf_event *event,
u64 values[4];
int n = 0;
- values[n++] = perf_event_read_value(event, &enabled, &running);
+ values[n++] = __perf_event_read_value(event, &enabled, &running);
if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
values[n++] = enabled;
if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
@@ -4861,8 +4820,7 @@ static void calc_timer_values(struct perf_event *event,
*now = perf_clock();
ctx_time = event->shadow_ctx_time + *now;
- *enabled = ctx_time - event->tstamp_enabled;
- *running = ctx_time - event->tstamp_running;
+ __perf_update_times(event, ctx_time, enabled, running);
}
static void perf_event_init_userpage(struct perf_event *event)
@@ -5090,7 +5048,7 @@ static void perf_mmap_open(struct vm_area_struct *vma)
atomic_inc(&event->rb->aux_mmap_count);
if (event->pmu->event_mapped)
- event->pmu->event_mapped(event);
+ event->pmu->event_mapped(event, vma->vm_mm);
}
static void perf_pmu_output_stop(struct perf_event *event);
@@ -5113,7 +5071,7 @@ static void perf_mmap_close(struct vm_area_struct *vma)
unsigned long size = perf_data_size(rb);
if (event->pmu->event_unmapped)
- event->pmu->event_unmapped(event);
+ event->pmu->event_unmapped(event, vma->vm_mm);
/*
* rb->aux_mmap_count will always drop before rb->mmap_count and
@@ -5266,8 +5224,8 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
if (!rb)
goto aux_unlock;
- aux_offset = ACCESS_ONCE(rb->user_page->aux_offset);
- aux_size = ACCESS_ONCE(rb->user_page->aux_size);
+ aux_offset = READ_ONCE(rb->user_page->aux_offset);
+ aux_size = READ_ONCE(rb->user_page->aux_size);
if (aux_offset < perf_data_size(rb) + PAGE_SIZE)
goto aux_unlock;
@@ -5411,7 +5369,7 @@ aux_unlock:
vma->vm_ops = &perf_mmap_vmops;
if (event->pmu->event_mapped)
- event->pmu->event_mapped(event);
+ event->pmu->event_mapped(event, vma->vm_mm);
return ret;
}
@@ -5972,6 +5930,9 @@ void perf_output_sample(struct perf_output_handle *handle,
}
}
+ if (sample_type & PERF_SAMPLE_PHYS_ADDR)
+ perf_output_put(handle, data->phys_addr);
+
if (!event->attr.watermark) {
int wakeup_events = event->attr.wakeup_events;
@@ -5987,6 +5948,38 @@ void perf_output_sample(struct perf_output_handle *handle,
}
}
+static u64 perf_virt_to_phys(u64 virt)
+{
+ u64 phys_addr = 0;
+ struct page *p = NULL;
+
+ if (!virt)
+ return 0;
+
+ if (virt >= TASK_SIZE) {
+ /* If it's vmalloc()d memory, leave phys_addr as 0 */
+ if (virt_addr_valid((void *)(uintptr_t)virt) &&
+ !(virt >= VMALLOC_START && virt < VMALLOC_END))
+ phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt);
+ } else {
+ /*
+ * Walking the pages tables for user address.
+ * Interrupts are disabled, so it prevents any tear down
+ * of the page tables.
+ * Try IRQ-safe __get_user_pages_fast first.
+ * If failed, leave phys_addr as 0.
+ */
+ if ((current->mm != NULL) &&
+ (__get_user_pages_fast(virt, 1, 0, &p) == 1))
+ phys_addr = page_to_phys(p) + virt % PAGE_SIZE;
+
+ if (p)
+ put_page(p);
+ }
+
+ return phys_addr;
+}
+
void perf_prepare_sample(struct perf_event_header *header,
struct perf_sample_data *data,
struct perf_event *event,
@@ -6105,6 +6098,9 @@ void perf_prepare_sample(struct perf_event_header *header,
header->size += size;
}
+
+ if (sample_type & PERF_SAMPLE_PHYS_ADDR)
+ data->phys_addr = perf_virt_to_phys(data->addr);
}
static void __always_inline
@@ -6680,6 +6676,7 @@ static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info,
ns_inode = ns_path.dentry->d_inode;
ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev);
ns_link_info->ino = ns_inode->i_ino;
+ path_put(&ns_path);
}
}
@@ -7256,6 +7253,11 @@ static void perf_log_throttle(struct perf_event *event, int enable)
perf_output_end(&handle);
}
+void perf_event_itrace_started(struct perf_event *event)
+{
+ event->attach_state |= PERF_ATTACH_ITRACE;
+}
+
static void perf_log_itrace_start(struct perf_event *event)
{
struct perf_output_handle handle;
@@ -7271,7 +7273,7 @@ static void perf_log_itrace_start(struct perf_event *event)
event = event->parent;
if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) ||
- event->hw.itrace_started)
+ event->attach_state & PERF_ATTACH_ITRACE)
return;
rec.header.type = PERF_RECORD_ITRACE_START;
@@ -7865,11 +7867,9 @@ void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx,
struct pt_regs *regs, struct hlist_head *head,
struct task_struct *task)
{
- struct bpf_prog *prog = call->prog;
-
- if (prog) {
+ if (bpf_prog_array_valid(call)) {
*(struct pt_regs **)raw_data = regs;
- if (!trace_call_bpf(prog, raw_data) || hlist_empty(head)) {
+ if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) {
perf_swevent_put_recursion_context(rctx);
return;
}
@@ -7988,6 +7988,7 @@ static void bpf_overflow_handler(struct perf_event *event,
struct bpf_perf_event_data_kern ctx = {
.data = data,
.regs = regs,
+ .event = event,
};
int ret = 0;
@@ -8050,18 +8051,17 @@ static void perf_event_free_bpf_handler(struct perf_event *event)
static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd)
{
- bool is_kprobe, is_tracepoint;
+ bool is_kprobe, is_tracepoint, is_syscall_tp;
struct bpf_prog *prog;
+ int ret;
if (event->attr.type != PERF_TYPE_TRACEPOINT)
return perf_event_set_bpf_handler(event, prog_fd);
- if (event->tp_event->prog)
- return -EEXIST;
-
is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE;
is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT;
- if (!is_kprobe && !is_tracepoint)
+ is_syscall_tp = is_syscall_trace_event(event->tp_event);
+ if (!is_kprobe && !is_tracepoint && !is_syscall_tp)
/* bpf programs can only be attached to u/kprobe or tracepoint */
return -EINVAL;
@@ -8070,13 +8070,14 @@ static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd)
return PTR_ERR(prog);
if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) ||
- (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT)) {
+ (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) ||
+ (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) {
/* valid fd, but invalid bpf program type */
bpf_prog_put(prog);
return -EINVAL;
}
- if (is_tracepoint) {
+ if (is_tracepoint || is_syscall_tp) {
int off = trace_event_get_offsets(event->tp_event);
if (prog->aux->max_ctx_offset > off) {
@@ -8084,25 +8085,20 @@ static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd)
return -EACCES;
}
}
- event->tp_event->prog = prog;
- return 0;
+ ret = perf_event_attach_bpf_prog(event, prog);
+ if (ret)
+ bpf_prog_put(prog);
+ return ret;
}
static void perf_event_free_bpf_prog(struct perf_event *event)
{
- struct bpf_prog *prog;
-
- perf_event_free_bpf_handler(event);
-
- if (!event->tp_event)
+ if (event->attr.type != PERF_TYPE_TRACEPOINT) {
+ perf_event_free_bpf_handler(event);
return;
-
- prog = event->tp_event->prog;
- if (prog) {
- event->tp_event->prog = NULL;
- bpf_prog_put(prog);
}
+ perf_event_detach_bpf_prog(event);
}
#else
@@ -8868,6 +8864,14 @@ static struct perf_cpu_context __percpu *find_pmu_context(int ctxn)
static void free_pmu_context(struct pmu *pmu)
{
+ /*
+ * Static contexts such as perf_sw_context have a global lifetime
+ * and may be shared between different PMUs. Avoid freeing them
+ * when a single PMU is going away.
+ */
+ if (pmu->task_ctx_nr > perf_invalid_context)
+ return;
+
mutex_lock(&pmus_lock);
free_percpu(pmu->pmu_cpu_context);
mutex_unlock(&pmus_lock);
@@ -9307,6 +9311,11 @@ static void account_event(struct perf_event *event)
inc = true;
if (inc) {
+ /*
+ * We need the mutex here because static_branch_enable()
+ * must complete *before* the perf_sched_count increment
+ * becomes visible.
+ */
if (atomic_inc_not_zero(&perf_sched_count))
goto enabled;
@@ -9580,6 +9589,8 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr,
if (ret)
return -EFAULT;
+ attr->size = size;
+
if (attr->__reserved_1)
return -EINVAL;
@@ -9852,6 +9863,11 @@ SYSCALL_DEFINE5(perf_event_open,
return -EINVAL;
}
+ /* Only privileged users can get physical addresses */
+ if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR) &&
+ perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN))
+ return -EACCES;
+
if (!attr.sample_max_stack)
attr.sample_max_stack = sysctl_perf_event_max_stack;
@@ -10001,28 +10017,27 @@ SYSCALL_DEFINE5(perf_event_open,
goto err_context;
/*
- * Do not allow to attach to a group in a different
- * task or CPU context:
+ * Make sure we're both events for the same CPU;
+ * grouping events for different CPUs is broken; since
+ * you can never concurrently schedule them anyhow.
*/
- if (move_group) {
- /*
- * Make sure we're both on the same task, or both
- * per-cpu events.
- */
- if (group_leader->ctx->task != ctx->task)
- goto err_context;
+ if (group_leader->cpu != event->cpu)
+ goto err_context;
- /*
- * Make sure we're both events for the same CPU;
- * grouping events for different CPUs is broken; since
- * you can never concurrently schedule them anyhow.
- */
- if (group_leader->cpu != event->cpu)
- goto err_context;
- } else {
- if (group_leader->ctx != ctx)
- goto err_context;
- }
+ /*
+ * Make sure we're both on the same task, or both
+ * per-CPU events.
+ */
+ if (group_leader->ctx->task != ctx->task)
+ goto err_context;
+
+ /*
+ * Do not allow to attach to a group in a different task
+ * or CPU context. If we're moving SW events, we'll fix
+ * this up later, so allow that.
+ */
+ if (!move_group && group_leader->ctx != ctx)
+ goto err_context;
/*
* Only a group leader can be exclusive or pinned
@@ -10426,7 +10441,7 @@ perf_event_exit_event(struct perf_event *child_event,
if (parent_event)
perf_group_detach(child_event);
list_del_event(child_event, child_ctx);
- child_event->state = PERF_EVENT_STATE_EXIT; /* is_event_hup() */
+ perf_event_set_state(child_event, PERF_EVENT_STATE_EXIT); /* is_event_hup() */
raw_spin_unlock_irq(&child_ctx->lock);
/*
@@ -10664,7 +10679,7 @@ inherit_event(struct perf_event *parent_event,
struct perf_event *group_leader,
struct perf_event_context *child_ctx)
{
- enum perf_event_active_state parent_state = parent_event->state;
+ enum perf_event_state parent_state = parent_event->state;
struct perf_event *child_event;
unsigned long flags;
@@ -11000,6 +11015,7 @@ static void __perf_event_exit_context(void *__info)
struct perf_event *event;
raw_spin_lock(&ctx->lock);
+ ctx_sched_out(ctx, cpuctx, EVENT_TIME);
list_for_each_entry(event, &ctx->event_list, event_entry)
__perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP);
raw_spin_unlock(&ctx->lock);
@@ -11201,5 +11217,6 @@ struct cgroup_subsys perf_event_cgrp_subsys = {
* controller is not mounted on a legacy hierarchy.
*/
.implicit_on_dfl = true,
+ .threaded = true,
};
#endif /* CONFIG_CGROUP_PERF */
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