summaryrefslogtreecommitdiff
path: root/drivers/perf/arm_pmu.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/perf/arm_pmu.c')
-rw-r--r--drivers/perf/arm_pmu.c23
1 files changed, 21 insertions, 2 deletions
diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index 32346b5a8a11..f2d01d4d9364 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;
@@ -836,6 +847,14 @@ static int cpu_pmu_init(struct arm_pmu *cpu_pmu)
if (!platform_get_irq(cpu_pmu->plat_device, 0))
cpu_pmu->pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT;
+ /*
+ * This is a CPU PMU potentially in a heterogeneous configuration (e.g.
+ * big.LITTLE). This is not an uncore PMU, and we have taken ctx
+ * sharing into account (e.g. with our pmu::filter_match callback and
+ * pmu::event_init group validation).
+ */
+ cpu_pmu->pmu.capabilities |= PERF_PMU_CAP_HETEROGENEOUS_CPUS;
+
return 0;
out_unregister: