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Shenoy" To: "Rafael J. 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Wysocki wrote: > From: Rafael J. Wysocki > > After a previous change, cpuidle_play_dead(), which is the only caller > of idle state :enter_dead() callbacks, ignores their return values, so > they may as well be void. > > Suggested-by: Peter Zijlstra > Signed-off-by: Rafael J. Wysocki > --- > > v1 -> v2: New patch > > Interestingly enough, the only user of :enter_dead() idle state callbacks > in the current mainline turns out to be ACPI idle. For that matter, the only user of cpuidle_play_dead() is the native_play_dead(). Was that always the case? Some of the other architectures select the deepest available idle state at boot time, and enter that state when a CPU is offlined. In any case I am ok with this. Reviewed-by: Gautham R. Shenoy -- Thanks and Regards gautham. > > --- > drivers/acpi/processor_idle.c | 7 ++----- > include/linux/cpuidle.h | 2 +- > 2 files changed, 3 insertions(+), 6 deletions(-) > > Index: linux-pm/include/linux/cpuidle.h > =================================================================== > --- linux-pm.orig/include/linux/cpuidle.h > +++ linux-pm/include/linux/cpuidle.h > @@ -61,7 +61,7 @@ struct cpuidle_state { > struct cpuidle_driver *drv, > int index); > > - int (*enter_dead) (struct cpuidle_device *dev, int index); > + void (*enter_dead) (struct cpuidle_device *dev, int index); > > /* > * CPUs execute ->enter_s2idle with the local tick or entire timekeeping > Index: linux-pm/drivers/acpi/processor_idle.c > =================================================================== > --- linux-pm.orig/drivers/acpi/processor_idle.c > +++ linux-pm/drivers/acpi/processor_idle.c > @@ -578,7 +578,7 @@ static void __cpuidle acpi_idle_do_entry > * @dev: the target CPU > * @index: the index of suggested state > */ > -static int acpi_idle_play_dead(struct cpuidle_device *dev, int index) > +static void acpi_idle_play_dead(struct cpuidle_device *dev, int index) > { > struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu); > > @@ -591,11 +591,8 @@ static int acpi_idle_play_dead(struct cp > else if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) { > io_idle(cx->address); > } else > - return -ENODEV; > + return; > } > - > - /* Never reached */ > - return 0; > } > > static __always_inline bool acpi_idle_fallback_to_c1(struct acpi_processor *pr) > > >