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Diffstat (limited to 'kernel/events/core.c')
-rw-r--r--kernel/events/core.c75
1 files changed, 71 insertions, 4 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c
index e3589c4287cb..0e9cfe6f3535 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -2146,7 +2146,7 @@ static void perf_put_aux_event(struct perf_event *event)
static bool perf_need_aux_event(struct perf_event *event)
{
- return !!event->attr.aux_output || !!event->attr.aux_sample_size;
+ return event->attr.aux_output || has_aux_action(event);
}
static int perf_get_aux_event(struct perf_event *event,
@@ -2171,6 +2171,10 @@ static int perf_get_aux_event(struct perf_event *event,
!perf_aux_output_match(event, group_leader))
return 0;
+ if ((event->attr.aux_pause || event->attr.aux_resume) &&
+ !(group_leader->pmu->capabilities & PERF_PMU_CAP_AUX_PAUSE))
+ return 0;
+
if (event->attr.aux_sample_size && !group_leader->pmu->snapshot_aux)
return 0;
@@ -8016,6 +8020,49 @@ void perf_prepare_header(struct perf_event_header *header,
WARN_ON_ONCE(header->size & 7);
}
+static void __perf_event_aux_pause(struct perf_event *event, bool pause)
+{
+ if (pause) {
+ if (!event->hw.aux_paused) {
+ event->hw.aux_paused = 1;
+ event->pmu->stop(event, PERF_EF_PAUSE);
+ }
+ } else {
+ if (event->hw.aux_paused) {
+ event->hw.aux_paused = 0;
+ event->pmu->start(event, PERF_EF_RESUME);
+ }
+ }
+}
+
+static void perf_event_aux_pause(struct perf_event *event, bool pause)
+{
+ struct perf_buffer *rb;
+
+ if (WARN_ON_ONCE(!event))
+ return;
+
+ rb = ring_buffer_get(event);
+ if (!rb)
+ return;
+
+ scoped_guard (irqsave) {
+ /*
+ * Guard against self-recursion here. Another event could trip
+ * this same from NMI context.
+ */
+ if (READ_ONCE(rb->aux_in_pause_resume))
+ break;
+
+ WRITE_ONCE(rb->aux_in_pause_resume, 1);
+ barrier();
+ __perf_event_aux_pause(event, pause);
+ barrier();
+ WRITE_ONCE(rb->aux_in_pause_resume, 0);
+ }
+ ring_buffer_put(rb);
+}
+
static __always_inline int
__perf_event_output(struct perf_event *event,
struct perf_sample_data *data,
@@ -9818,9 +9865,12 @@ static int __perf_event_overflow(struct perf_event *event,
ret = __perf_event_account_interrupt(event, throttle);
+ if (event->attr.aux_pause)
+ perf_event_aux_pause(event->aux_event, true);
+
if (event->prog && event->prog->type == BPF_PROG_TYPE_PERF_EVENT &&
!bpf_overflow_handler(event, data, regs))
- return ret;
+ goto out;
/*
* XXX event_limit might not quite work as expected on inherited
@@ -9882,6 +9932,9 @@ static int __perf_event_overflow(struct perf_event *event,
event->pending_wakeup = 1;
irq_work_queue(&event->pending_irq);
}
+out:
+ if (event->attr.aux_resume)
+ perf_event_aux_pause(event->aux_event, false);
return ret;
}
@@ -12273,11 +12326,25 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
}
if (event->attr.aux_output &&
- !(pmu->capabilities & PERF_PMU_CAP_AUX_OUTPUT)) {
+ (!(pmu->capabilities & PERF_PMU_CAP_AUX_OUTPUT) ||
+ event->attr.aux_pause || event->attr.aux_resume)) {
err = -EOPNOTSUPP;
goto err_pmu;
}
+ if (event->attr.aux_pause && event->attr.aux_resume) {
+ err = -EINVAL;
+ goto err_pmu;
+ }
+
+ if (event->attr.aux_start_paused) {
+ if (!(pmu->capabilities & PERF_PMU_CAP_AUX_PAUSE)) {
+ err = -EOPNOTSUPP;
+ goto err_pmu;
+ }
+ event->hw.aux_paused = 1;
+ }
+
if (cgroup_fd != -1) {
err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader);
if (err)
@@ -13073,7 +13140,7 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
* Grouping is not supported for kernel events, neither is 'AUX',
* make sure the caller's intentions are adjusted.
*/
- if (attr->aux_output)
+ if (attr->aux_output || attr->aux_action)
return ERR_PTR(-EINVAL);
event = perf_event_alloc(attr, cpu, task, NULL, NULL,