cpuidle / ACPI: remove unused CPUIDLE_FLAG_TIME_INVALID (62c4cf97) · Commits · 戴 / test

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> Acked-by:

Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by:

Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/processor_idle.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -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;

include/linux/cpuidle.h

+0 −3

Original line number	Diff line number	Diff line
		@@ -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)
		{

Admin message