[PATCH v1] cpuidle: Do not return from cpuidle_play_dead() on callback failures
From: Rafael J. Wysocki
Date: Thu Nov 14 2024 - 12:46:35 EST
From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
If the :enter_dead() idle state callback fails for a certain state,
there may be still a shallower state for which it will work.
Because the only caller of cpuidle_play_dead(), native_play_dead(),
falls back to hlt_play_dead() if it returns an error, it should
better try all of the idle states for which :enter_dead() is present
before failing, so change it accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/cpuidle/cpuidle.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
Index: linux-pm/drivers/cpuidle/cpuidle.c
===================================================================
--- linux-pm.orig/drivers/cpuidle/cpuidle.c
+++ linux-pm/drivers/cpuidle/cpuidle.c
@@ -70,9 +70,10 @@ int cpuidle_play_dead(void)
return -ENODEV;
/* Find lowest-power state that supports long-term idle */
- for (i = drv->state_count - 1; i >= 0; i--)
- if (drv->states[i].enter_dead)
- return drv->states[i].enter_dead(dev, i);
+ for (i = drv->state_count - 1; i >= 0; i--) {
+ if (drv->states[i].enter_dead && !drv->states[i].enter_dead(dev, i))
+ return 0;
+ }
return -ENODEV;
}