diff mbox series

[v2,10/44] cpuidle,armada: Push RCU-idle into driver

Message ID 20220919101521.004425686@infradead.org (mailing list archive)
State Handled Elsewhere, archived
Headers show
Series cpuidle,rcu: Clean up the mess | expand

Commit Message

Peter Zijlstra Sept. 19, 2022, 9:59 a.m. UTC 
Doing RCU-idle outside the driver, only to then temporarily enable it
again before going idle is daft.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
 drivers/cpuidle/cpuidle-mvebu-v7.c |    7 +++++++
 1 file changed, 7 insertions(+)

Comments

Frederic Weisbecker Sept. 19, 2022, 2:39 p.m. UTC | #1 
On Mon, Sep 19, 2022 at 11:59:49AM +0200, Peter Zijlstra wrote:
> Doing RCU-idle outside the driver, only to then temporarily enable it
> again before going idle is daft.

Ah wait, now I see, that's cpu_pm_enter()/cpu_pm_exit() -> cpu_pm_notify*() the culprits.
Might be worth adding a short note about that on your changelogs.

> 
> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> ---
>  drivers/cpuidle/cpuidle-mvebu-v7.c |    7 +++++++
>  1 file changed, 7 insertions(+)
> 
> --- a/drivers/cpuidle/cpuidle-mvebu-v7.c
> +++ b/drivers/cpuidle/cpuidle-mvebu-v7.c
> @@ -36,7 +36,10 @@ static int mvebu_v7_enter_idle(struct cp
>  	if (drv->states[index].flags & MVEBU_V7_FLAG_DEEP_IDLE)
>  		deepidle = true;
>  
> +	ct_idle_enter();
>  	ret = mvebu_v7_cpu_suspend(deepidle);
> +	ct_idle_exit();

And then yes of course:

Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
diff mbox series

Patch

--- a/drivers/cpuidle/cpuidle-mvebu-v7.c
+++ b/drivers/cpuidle/cpuidle-mvebu-v7.c
@@ -36,7 +36,10 @@  static int mvebu_v7_enter_idle(struct cp
 	if (drv->states[index].flags & MVEBU_V7_FLAG_DEEP_IDLE)
 		deepidle = true;
 
+	ct_idle_enter();
 	ret = mvebu_v7_cpu_suspend(deepidle);
+	ct_idle_exit();
+
 	cpu_pm_exit();
 
 	if (ret)
@@ -49,6 +52,7 @@  static struct cpuidle_driver armadaxp_id
 	.name			= "armada_xp_idle",
 	.states[0]		= ARM_CPUIDLE_WFI_STATE,
 	.states[1]		= {
+		.flags			= CPUIDLE_FLAG_RCU_IDLE,
 		.enter			= mvebu_v7_enter_idle,
 		.exit_latency		= 100,
 		.power_usage		= 50,
@@ -57,6 +61,7 @@  static struct cpuidle_driver armadaxp_id
 		.desc			= "CPU power down",
 	},
 	.states[2]		= {
+		.flags			= CPUIDLE_FLAG_RCU_IDLE,
 		.enter			= mvebu_v7_enter_idle,
 		.exit_latency		= 1000,
 		.power_usage		= 5,
@@ -72,6 +77,7 @@  static struct cpuidle_driver armada370_i
 	.name			= "armada_370_idle",
 	.states[0]		= ARM_CPUIDLE_WFI_STATE,
 	.states[1]		= {
+		.flags			= CPUIDLE_FLAG_RCU_IDLE,
 		.enter			= mvebu_v7_enter_idle,
 		.exit_latency		= 100,
 		.power_usage		= 5,
@@ -87,6 +93,7 @@  static struct cpuidle_driver armada38x_i
 	.name			= "armada_38x_idle",
 	.states[0]		= ARM_CPUIDLE_WFI_STATE,
 	.states[1]		= {
+		.flags			= CPUIDLE_FLAG_RCU_IDLE,
 		.enter			= mvebu_v7_enter_idle,
 		.exit_latency		= 10,
 		.power_usage		= 5,