| Message ID | 2d1595ea66f8eadeb1e337354b311c4f5282e2a1.1418712225.git.len.brown@intel.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On 12/16/2014 07:52 AM, Len Brown wrote: > From: Len Brown <len.brown@intel.com> > > CPUIDLE_FLAG_TIME_INVALID is no longer checked > by menu or ladder cpuidle governors, so don't > bother setting or defining it. > > It was originally invented to account for the fact that > acpi_safe_halt() enables interrupts to invoke HLT. > That would allow interrupt service routines to be included > in the last_idle duration measurements made in cpuidle_enter_state(), > potentially returning a duration much larger than reality. > > But menu and ladder can gracefully handle erroneously large duration > intervals without checking for CPUIDLE_FLAG_TIME_INVALID. > Further, if they don't check CPUIDLE_FLAG_TIME_INVALID, they > can also benefit from the instances when the duration interval > is not erroneously large. > > Signed-off-by: Len Brown <len.brown@intel.com> > Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> > --- > drivers/acpi/processor_idle.c | 2 -- > include/linux/cpuidle.h | 3 --- > 2 files changed, 5 deletions(-) > > diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c > index 4995365..87b704e 100644 > --- a/drivers/acpi/processor_idle.c > +++ b/drivers/acpi/processor_idle.c > @@ -985,8 +985,6 @@ static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr) > state->flags = 0; > switch (cx->type) { > case ACPI_STATE_C1: > - if (cx->entry_method != ACPI_CSTATE_FFH) > - state->flags |= CPUIDLE_FLAG_TIME_INVALID; > > state->enter = acpi_idle_enter_c1; > state->enter_dead = acpi_idle_play_dead; > diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h > index a07e087..ab70f3b 100644 > --- a/include/linux/cpuidle.h > +++ b/include/linux/cpuidle.h > @@ -53,7 +53,6 @@ struct cpuidle_state { > }; > > /* Idle State Flags */ > -#define CPUIDLE_FLAG_TIME_INVALID (0x01) /* is residency time measurable? */ > #define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */ > #define CPUIDLE_FLAG_TIMER_STOP (0x04) /* timer is stopped on this state */ > > @@ -89,8 +88,6 @@ DECLARE_PER_CPU(struct cpuidle_device, cpuidle_dev); > /** > * cpuidle_get_last_residency - retrieves the last state's residency time > * @dev: the target CPU > - * > - * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_INVALID is set > */ > static inline int cpuidle_get_last_residency(struct cpuidle_device *dev) > { >
On Tuesday, December 16, 2014 12:08:25 PM Daniel Lezcano wrote: > On 12/16/2014 07:52 AM, Len Brown wrote: > > From: Len Brown <len.brown@intel.com> > > > > CPUIDLE_FLAG_TIME_INVALID is no longer checked > > by menu or ladder cpuidle governors, so don't > > bother setting or defining it. > > > > It was originally invented to account for the fact that > > acpi_safe_halt() enables interrupts to invoke HLT. > > That would allow interrupt service routines to be included > > in the last_idle duration measurements made in cpuidle_enter_state(), > > potentially returning a duration much larger than reality. > > > > But menu and ladder can gracefully handle erroneously large duration > > intervals without checking for CPUIDLE_FLAG_TIME_INVALID. > > Further, if they don't check CPUIDLE_FLAG_TIME_INVALID, they > > can also benefit from the instances when the duration interval > > is not erroneously large. > > > > Signed-off-by: Len Brown <len.brown@intel.com> > > Cc: Daniel Lezcano <daniel.lezcano@linaro.org> > > Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> OK Since the material for my next pull request is staged already, I'm going to queue up this series for 3.19-rc, but I'll most likely push it for -rc2. Thanks! > > --- > > drivers/acpi/processor_idle.c | 2 -- > > include/linux/cpuidle.h | 3 --- > > 2 files changed, 5 deletions(-) > > > > diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c > > index 4995365..87b704e 100644 > > --- a/drivers/acpi/processor_idle.c > > +++ b/drivers/acpi/processor_idle.c > > @@ -985,8 +985,6 @@ static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr) > > state->flags = 0; > > switch (cx->type) { > > case ACPI_STATE_C1: > > - if (cx->entry_method != ACPI_CSTATE_FFH) > > - state->flags |= CPUIDLE_FLAG_TIME_INVALID; > > > > state->enter = acpi_idle_enter_c1; > > state->enter_dead = acpi_idle_play_dead; > > diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h > > index a07e087..ab70f3b 100644 > > --- a/include/linux/cpuidle.h > > +++ b/include/linux/cpuidle.h > > @@ -53,7 +53,6 @@ struct cpuidle_state { > > }; > > > > /* Idle State Flags */ > > -#define CPUIDLE_FLAG_TIME_INVALID (0x01) /* is residency time measurable? */ > > #define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */ > > #define CPUIDLE_FLAG_TIMER_STOP (0x04) /* timer is stopped on this state */ > > > > @@ -89,8 +88,6 @@ DECLARE_PER_CPU(struct cpuidle_device, cpuidle_dev); > > /** > > * cpuidle_get_last_residency - retrieves the last state's residency time > > * @dev: the target CPU > > - * > > - * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_INVALID is set > > */ > > static inline int cpuidle_get_last_residency(struct cpuidle_device *dev) > > { > > > > >
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 4995365..87b704e 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -985,8 +985,6 @@ static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr) state->flags = 0; switch (cx->type) { case ACPI_STATE_C1: - if (cx->entry_method != ACPI_CSTATE_FFH) - state->flags |= CPUIDLE_FLAG_TIME_INVALID; state->enter = acpi_idle_enter_c1; state->enter_dead = acpi_idle_play_dead; diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index a07e087..ab70f3b 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -53,7 +53,6 @@ struct cpuidle_state { }; /* Idle State Flags */ -#define CPUIDLE_FLAG_TIME_INVALID (0x01) /* is residency time measurable? */ #define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */ #define CPUIDLE_FLAG_TIMER_STOP (0x04) /* timer is stopped on this state */ @@ -89,8 +88,6 @@ DECLARE_PER_CPU(struct cpuidle_device, cpuidle_dev); /** * cpuidle_get_last_residency - retrieves the last state's residency time * @dev: the target CPU - * - * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_INVALID is set */ static inline int cpuidle_get_last_residency(struct cpuidle_device *dev) {