user/sven/linux.git/include/linux/cpuidle.h, branch v4.17.13

cpuidle: Return nohz hint from cpuidle_select()

2018-04-06T07:29:34Z

Add a new pointer argument to cpuidle_select() and to the ->select cpuidle governor callback to allow a boolean value indicating whether or not the tick should be stopped before entering the selected state to be returned from there. Make the ladder governor ignore that pointer (to preserve its current behavior) and make the menu governor return 'false" through it if: (1) the idle exit latency is constrained at 0, or (2) the selected state is a polling one, or (3) the expected idle period duration is within the tick period range. In addition to that, the correction factor computations in the menu governor need to take the possibility that the tick may not be stopped into account to avoid artificially small correction factor values. To that end, add a mechanism to record tick wakeups, as suggested by Peter Zijlstra, and use it to modify the menu_update() behavior when tick wakeup occurs. Namely, if the CPU is woken up by the tick and the return value of tick_nohz_get_sleep_length() is not within the tick boundary, the predicted idle duration is likely too short, so make menu_update() try to compensate for that by updating the governor statistics as though the CPU was idle for a long time. Since the value returned through the new argument pointer of cpuidle_select() is not used by its caller yet, this change by itself is not expected to alter the functionality of the code. Signed-off-by: Rafael J. Wysocki Acked-by: Peter Zijlstra (Intel)

PM: cpuidle/suspend: Add s2idle usage and time state attributes

2018-03-29T11:06:08Z

Add a new attribute group called "s2idle" under the sysfs directory of each cpuidle state that supports the ->enter_s2idle callback and put two new attributes, "usage" and "time", into that group to represent the number of times the given state was requested for suspend-to-idle and the total time spent in suspend-to-idle after requesting that state, respectively. That will allow diagnostic information related to suspend-to-idle to be collected without enabling advanced debug features and analyzing dmesg output. Signed-off-by: Rafael J. Wysocki

Merge branches 'pm-cpuidle' and 'pm-opp'

2018-02-15T11:01:53Z

* pm-cpuidle: PM: cpuidle: Fix cpuidle_poll_state_init() prototype Documentation/ABI: update cpuidle sysfs documentation * pm-opp: opp: cpu: Replace GFP_ATOMIC with GFP_KERNEL in dev_pm_opp_init_cpufreq_table

PM: cpuidle: Fix cpuidle_poll_state_init() prototype

2018-02-12T10:34:22Z

Commit f85942207516 (x86: PM: Make APM idle driver initialize polling state) made apm_init() call cpuidle_poll_state_init(), but that only is defined for CONFIG_CPU_IDLE set, so make the empty stub of it available for CONFIG_CPU_IDLE unset too to fix the resulting build issue. Fixes: f85942207516 (x86: PM: Make APM idle driver initialize polling state) Cc: 4.14+ # 4.14+ Signed-off-by: Rafael J. Wysocki

cpuidle: Add new macro to enter a retention idle state

2018-01-02T13:48:55Z

If a CPU is entering a low power idle state where it doesn't lose any context, then there is no need to call cpu_pm_enter()/cpu_pm_exit(). Add a new macro(CPU_PM_CPU_IDLE_ENTER_RETENTION) to be used by cpuidle drivers when they are entering retention state. By not calling cpu_pm_enter and cpu_pm_exit we reduce the latency involved in entering and exiting the retention idle states. CPU_PM_CPU_IDLE_ENTER_RETENTION assumes that no state is lost and hence CPU PM notifiers will not be called. We may need a broader change if we need to support partial retention states effeciently. On ARM64 based Qualcomm Server Platform we measured below overhead for for calling cpu_pm_enter and cpu_pm_exit for retention states. workload: stress --hdd #CPUs --hdd-bytes 32M -t 30 Average overhead of cpu_pm_enter - 1.2us Average overhead of cpu_pm_exit - 3.1us Acked-by: Rafael J. Wysocki Acked-by: Sudeep Holla Signed-off-by: Prashanth Prakash Signed-off-by: Catalin Marinas

Merge branch 'pm-sleep'

2017-09-03T22:06:02Z

* pm-sleep: ACPI / PM: Check low power idle constraints for debug only PM / s2idle: Rename platform operations structure PM / s2idle: Rename ->enter_freeze to ->enter_s2idle PM / s2idle: Rename freeze_state enum and related items PM / s2idle: Rename PM_SUSPEND_FREEZE to PM_SUSPEND_TO_IDLE ACPI / PM: Prefer suspend-to-idle over S3 on some systems platform/x86: intel-hid: Wake up Dell Latitude 7275 from suspend-to-idle PM / suspend: Define pr_fmt() in suspend.c PM / suspend: Use mem_sleep_labels[] strings in messages PM / sleep: Put pm_test under CONFIG_PM_SLEEP_DEBUG PM / sleep: Check pm_wakeup_pending() in __device_suspend_noirq() PM / core: Add error argument to dpm_show_time() PM / core: Split dpm_suspend_noirq() and dpm_resume_noirq() PM / s2idle: Rearrange the main suspend-to-idle loop PM / timekeeping: Print debug messages when requested PM / sleep: Mark suspend/hibernation start and finish PM / sleep: Do not print debug messages by default PM / suspend: Export pm_suspend_target_state

cpuidle: Make drivers initialize polling state

2017-08-30T01:06:33Z

Make the drivers that want to include the polling state into their states table initialize it explicitly and drop the initialization of it (which in fact is conditional, but that is not obvious from the code) from the core. Signed-off-by: Rafael J. Wysocki Tested-by: Sudeep Holla Acked-by: Daniel Lezcano

cpuidle: Move polling state initialization code to separate file

2017-08-30T01:06:27Z

Move the polling state initialization code to a separate file built conditionally on CONFIG_ARCH_HAS_CPU_RELAX to get rid of the #ifdef in driver.c. Signed-off-by: Rafael J. Wysocki Tested-by: Sudeep Holla Acked-by: Daniel Lezcano

cpuidle: Eliminate the CPUIDLE_DRIVER_STATE_START symbol

2017-08-30T01:05:29Z

On some architectures the first (index 0) idle state is a polling one and it doesn't really save energy, so there is the CPUIDLE_DRIVER_STATE_START symbol allowing some pieces of cpuidle code to avoid using that state. However, this makes the code rather hard to follow. It is better to explicitly avoid the polling state, so add a new cpuidle state flag CPUIDLE_FLAG_POLLING to mark it and make the relevant code check that flag for the first state instead of using the CPUIDLE_DRIVER_STATE_START symbol. In the ACPI processor driver that cannot always rely on the state flags (like before the states table has been set up) define a new internal symbol ACPI_IDLE_STATE_START equivalent to the CPUIDLE_DRIVER_STATE_START one and drop the latter. Signed-off-by: Rafael J. Wysocki Tested-by: Sudeep Holla Acked-by: Daniel Lezcano

PM / s2idle: Rename ->enter_freeze to ->enter_s2idle

2017-08-10T23:29:56Z

Rename the ->enter_freeze cpuidle driver callback to ->enter_s2idle to make it clear that it is used for entering suspend-to-idle and rename the related functions, variables and so on accordingly. Signed-off-by: Rafael J. Wysocki