linux/drivers/cpuidle
Rafael J. Wysocki 87c9fe6ee4 cpuidle: menu: Avoid selecting shallow states with stopped tick
If the scheduler tick has been stopped already and the governor
selects a shallow idle state, the CPU can spend a long time in that
state if the selection is based on an inaccurate prediction of idle
time.  That effect turns out to be relevant, so it needs to be
mitigated.

To that end, modify the menu governor to discard the result of the
idle time prediction if the tick is stopped and the predicted idle
time is less than the tick period length, unless the tick timer is
going to expire soon.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2018-04-09 11:54:57 +02:00
..
governors cpuidle: menu: Avoid selecting shallow states with stopped tick 2018-04-09 11:54:57 +02:00
Kconfig
Kconfig.arm
Kconfig.mips
Kconfig.powerpc
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
coupled.c
cpuidle-arm.c ARM: cpuidle: Drop memory allocation error message from arm_idle_init_cpu() 2018-03-05 12:39:32 +01:00
cpuidle-at91.c
cpuidle-big_little.c
cpuidle-calxeda.c
cpuidle-clps711x.c
cpuidle-cps.c Update MIPS email addresses 2017-11-03 09:02:30 -07:00
cpuidle-exynos.c cpuidle: Enable coupled cpuidle support on Exynos3250 platform 2018-03-29 13:06:08 +02:00
cpuidle-kirkwood.c
cpuidle-mvebu-v7.c
cpuidle-powernv.c cpuidle/powernv: avoid double irq enable coming out of idle 2018-01-18 15:43:43 +11:00
cpuidle-pseries.c powerpc/pseries/cpuidle: add polling idle for shared processor guests 2018-01-18 15:43:44 +11:00
cpuidle-ux500.c
cpuidle-zynq.c
cpuidle.c cpuidle: Return nohz hint from cpuidle_select() 2018-04-06 09:29:34 +02:00
cpuidle.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
driver.c
dt_idle_states.c
dt_idle_states.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
governor.c cpuidle: Avoid NULL argument in cpuidle_switch_governor() 2018-01-05 14:01:30 +01:00
poll_state.c cpuidle: poll_state: Avoid invoking local_clock() too often 2018-03-29 13:06:08 +02:00
sysfs.c PM: cpuidle/suspend: Add s2idle usage and time state attributes 2018-03-29 13:06:08 +02:00