[PATCH 3/3] perf: clarify comment regarding perf_pmu_contexts

[Cody P Schafer <cody@linux.vnet.ibm.com>]

Again, note that the behavior of task_ctx_nr < 0 is an exception.

Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
---
 kernel/events/core.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index e9f60d0..159ef12 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -6276,8 +6276,9 @@ static int perf_event_idx_default(struct perf_event *event)
 }
 
 /*
- * Ensures all contexts with the same task_ctx_nr have the same
- * pmu_cpu_context too.
+ * Ensures all contexts with the same task_ctx_nr (where that task_ctx_nr
+ * is >=0) have the same pmu_cpu_context too. Contexts with with negative (<0)
+ * task_ctx_nr do not share pmu_cpu_contexts.
  */
 static void *find_pmu_context(int ctxn)
 {
-- 
1.8.5.2