perf: Add lockdep assertions
Make various bugs easier to see.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/kernel/events/core.c b/kernel/events/core.c
index bf82441..c77b05d 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1246,6 +1246,8 @@
static void
list_add_event(struct perf_event *event, struct perf_event_context *ctx)
{
+ lockdep_assert_held(&ctx->lock);
+
WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT);
event->attach_state |= PERF_ATTACH_CONTEXT;
@@ -2342,8 +2344,10 @@
struct perf_cpu_context *cpuctx,
enum event_type_t event_type)
{
- struct perf_event *event;
int is_active = ctx->is_active;
+ struct perf_event *event;
+
+ lockdep_assert_held(&ctx->lock);
ctx->is_active &= ~event_type;
if (likely(!ctx->nr_events))
@@ -2725,8 +2729,10 @@
enum event_type_t event_type,
struct task_struct *task)
{
- u64 now;
int is_active = ctx->is_active;
+ u64 now;
+
+ lockdep_assert_held(&ctx->lock);
ctx->is_active |= event_type;
if (likely(!ctx->nr_events))