diff options
Diffstat (limited to 'drivers/perf/arm_pmu.c')
| -rw-r--r-- | drivers/perf/arm_pmu.c | 23 |
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: |