From: Peter Zijlstra <peterz@infradead.org>
Date: Thu, 12 Jan 2023 19:43:22 +0000 (+0100)
Subject: cpuidle, ARM/imx6: Push RCU-idle into driver
X-Git-Tag: io_uring-6.3-2023-03-03~49^2~64
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=b3f46658ce40a3467cda82f920dd9d5325ab0eaf;p=linux-block.git

cpuidle, ARM/imx6: Push RCU-idle into driver

Doing RCU-idle outside the driver, only to then temporarily enable it
again, at least twice, before going idle is suboptimal.

Notably both cpu_pm_enter() and cpu_cluster_pm_enter() implicity
re-enable RCU.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20230112195539.821714572@infradead.org
---

diff --git a/arch/arm/mach-imx/cpuidle-imx6sx.c b/arch/arm/mach-imx/cpuidle-imx6sx.c
index 74ea1720e3d8..1dc01f6b0f36 100644
--- a/arch/arm/mach-imx/cpuidle-imx6sx.c
+++ b/arch/arm/mach-imx/cpuidle-imx6sx.c
@@ -47,7 +47,9 @@ static int imx6sx_enter_wait(struct cpuidle_device *dev,
 		cpu_pm_enter();
 		cpu_cluster_pm_enter();
 
+		ct_idle_enter();
 		cpu_suspend(0, imx6sx_idle_finish);
+		ct_idle_exit();
 
 		cpu_cluster_pm_exit();
 		cpu_pm_exit();
@@ -87,7 +89,8 @@ static struct cpuidle_driver imx6sx_cpuidle_driver = {
 			 */
 			.exit_latency = 300,
 			.target_residency = 500,
-			.flags = CPUIDLE_FLAG_TIMER_STOP,
+			.flags = CPUIDLE_FLAG_TIMER_STOP |
+				 CPUIDLE_FLAG_RCU_IDLE,
 			.enter = imx6sx_enter_wait,
 			.name = "LOW-POWER-IDLE",
 			.desc = "ARM power off",