X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=drivers%2Fperf%2Farm_pmu.c;h=f70090897fdf19c9777c332401dd01de7b1efc52;hb=cbcc72e037b8a3eb1fad3c1ae22021df21c97a51;hp=32346b5a8a119789c1857c90ec13902616ace318;hpb=e531cdf50a8a0fb7a4d51c06e52097bd01e9bf7c;p=deliverable%2Flinux.git

diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index 32346b5a8a11..f70090897fdf 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c
@@ -737,8 +737,19 @@ static void cpu_pm_pmu_setup(struct arm_pmu *armpmu, unsigned long cmd)
 			break;
 		case CPU_PM_EXIT:
 		case CPU_PM_ENTER_FAILED:
-			 /* Restore and enable the counter */
-			armpmu_start(event, PERF_EF_RELOAD);
+			 /*
+			  * Restore and enable the counter.
+			  * armpmu_start() indirectly calls
+			  *
+			  * perf_event_update_userpage()
+			  *
+			  * that requires RCU read locking to be functional,
+			  * wrap the call within RCU_NONIDLE to make the
+			  * RCU subsystem aware this cpu is not idle from
+			  * an RCU perspective for the armpmu_start() call
+			  * duration.
+			  */
+			RCU_NONIDLE(armpmu_start(event, PERF_EF_RELOAD));
 			break;
 		default:
 			break;