[tip: sched/core] arm64, riscv, perf: Remove RCU_NONIDLE() usage

From: tip-bot2 for Peter Zijlstra
Date: Fri Jan 13 2023 - 07:33:17 EST


The following commit has been merged into the sched/core branch of tip:

Commit-ID: 1c38b0615f84f622cd6c821aa40be60fc7f7a096
Gitweb: https://git.kernel.org/tip/1c38b0615f84f622cd6c821aa40be60fc7f7a096
Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
AuthorDate: Thu, 12 Jan 2023 20:44:00 +01:00
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Fri, 13 Jan 2023 11:48:17 +01:00

arm64, riscv, perf: Remove RCU_NONIDLE() usage

The PM notifiers should no longer be ran with RCU disabled (per the
previous patches), as such this hack is no longer required either.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Tested-by: Tony Lindgren <tony@xxxxxxxxxxx>
Tested-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Acked-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230112195542.151174682@xxxxxxxxxxxxx
---
drivers/perf/arm_pmu.c | 11 +----------
drivers/perf/riscv_pmu_sbi.c | 8 +-------
2 files changed, 2 insertions(+), 17 deletions(-)

diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index 9b593f9..c34d5fe 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c
@@ -758,17 +758,8 @@ static void cpu_pm_pmu_setup(struct arm_pmu *armpmu, unsigned long cmd)
case CPU_PM_ENTER_FAILED:
/*
* 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));
+ armpmu_start(event, PERF_EF_RELOAD);
break;
default:
break;
diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
index f6507ef..7b2288d 100644
--- a/drivers/perf/riscv_pmu_sbi.c
+++ b/drivers/perf/riscv_pmu_sbi.c
@@ -771,14 +771,8 @@ static int riscv_pm_pmu_notify(struct notifier_block *b, unsigned long cmd,
case CPU_PM_ENTER_FAILED:
/*
* Restore and enable the counter.
- *
- * 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 riscv_pmu_start() call
- * duration.
*/
- RCU_NONIDLE(riscv_pmu_start(event, PERF_EF_RELOAD));
+ riscv_pmu_start(event, PERF_EF_RELOAD);
break;
default:
break;