Commit f65ee094 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

cpuidle: Do not return from cpuidle_play_dead() on callback failures 



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.

Also notice that the :enter_dead() state callback is not expected
to return on success (the CPU should be "dead" then), so make
cpuidle_play_dead() ignore its return value.

Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: default avatarMario Limonciello <mario.limonciello@amd.com>
Tested-by: Mario Limonciello <mario.limonciello@amd.com> # 6.12-rc7
Reviewed-by: default avatarGautham R. Shenoy <gautham.shenoy@amd.com>
Link: https://patch.msgid.link/3318440.aeNJFYEL58@rjwysocki.net
parent ad52c55e

drivers/cpuidle/cpuidle.c

+7 −3
Original line number Diff line number Diff line
@@ -69,11 +69,15 @@ int cpuidle_play_dead(void) 
	if (!drv)

		return -ENODEV;



	/* Find lowest-power state that supports long-term idle */

	for (i = drv->state_count - 1; i >= 0; i--)

	for (i = drv->state_count - 1; i >= 0; i--) {

		if (drv->states[i].enter_dead)

			return drv->states[i].enter_dead(dev, i);

			drv->states[i].enter_dead(dev, i);

	}



	/*

	 * If :enter_dead() is successful, it will never return, so reaching

	 * here means that all of them failed above or were not present.

	 */

	return -ENODEV;

}