Vincent Guittot 8234f6734c PM-runtime: Switch autosuspend over to using hrtimers ... PM-runtime uses the timer infrastructure for autosuspend. This implies that the minimum time before autosuspending a device is in the range of 1 tick included to 2 ticks excluded -On arm64 this means between 4ms and 8ms with default jiffies configuration -And on arm, it is between 10ms and 20ms These values are quite high for embedded systems which sometimes want the duration to be in the range of 1 ms. It is possible to switch autosuspend over to using hrtimers to get finer granularity for short durations and take advantage of slack to retain some margins and get long timeouts with minimum wakeups. On an arm64 platform that uses 1ms for autosuspending timeout of its GPU, idle power is reduced by 10% with hrtimer. The latency impact on arm64 hikey octo cores is: - mark_last_busy: from 1.11 us to 1.25 us - rpm_suspend: from 15.54 us to 15.38 us [Only the code path of rpm_suspend() that starts hrtimer has been measured.] arm64 image (arm64 default defconfig) decreases by around 3KB with following details: $ size vmlinux-timer text data bss dec hex filename 12034646 6869268 386840 19290754 1265a82 vmlinux $ size vmlinux-hrtimer text data bss dec hex filename 12030550 6870164 387032 19287746 1264ec2 vmlinux The latency impact on arm 32bits snowball dual cores is : - mark_last_busy: from 0.31 us usec to 0.77 us - rpm_suspend: from 6.83 us to 6.67 usec The increase of the image for snowball platform that I used for testing performance impact, is neglictable (244B). $ size vmlinux-timer text data bss dec hex filename 7157961 2119580 264120 9541661 91981d build-ux500/vmlinux size vmlinux-hrtimer text data bss dec hex filename 7157773 2119884 264248 9541905 919911 vmlinux-hrtimer And arm 32bits image (multi_v7_defconfig) increases by around 1.7KB with following details: $ size vmlinux-timer text data bss dec hex filename 13304443 6803420 402768 20510631 138f7a7 vmlinux $ size vmlinux-hrtimer text data bss dec hex filename 13304299 6805276 402768 20512343 138fe57 vmlinux Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>		2018-12-19 10:31:50 +01:00
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clock_ops.c	PM / clk: signedness bug in of_pm_clk_add_clks()	2018-08-24 11:52:34 +02:00
common.c	PM / Domains: Introduce dev_pm_domain_attach_by_name()	2018-07-09 12:11:02 +02:00
domain_governor.c	PM / QoS: Fix device resume latency framework	2017-11-08 12:14:51 +01:00
domain.c	PM / Domains: Deal with multiple states but no governor in genpd	2018-10-18 12:25:09 +02:00
generic_ops.c	PM / sleep: Remove pm_complete_with_resume_check()	2017-10-11 15:40:29 +02:00
main.c	PM / core: Clear the direct_complete flag on errors	2018-10-04 19:39:31 +02:00
Makefile	Merge branches 'pm-cpufreq-sched' and 'pm-opp'	2017-11-13 01:40:52 +01:00
power.h	PM / core: Drop unused internal inline functions for sysfs	2018-05-10 11:55:12 +02:00
qos.c	PM / QoS: Fix device resume latency framework	2017-11-08 12:14:51 +01:00
runtime.c	PM-runtime: Switch autosuspend over to using hrtimers	2018-12-19 10:31:50 +01:00
sysfs.c	PM / wakeup: Export wakeup_count instead of event_count via sysfs	2018-06-06 09:23:36 +02:00
trace.c	timekeeping: Ignore the bogus sleep time if pm_trace is enabled	2016-11-29 18:02:58 +01:00
wakeirq.c	PM / wakeirq: Add wakeup name to dedicated wake irqs	2018-02-26 23:23:37 +01:00
wakeup.c	Merge branches 'pm-pci', 'acpi-pm', 'pm-sleep' and 'pm-avs'	2018-06-04 10:41:53 +02:00