Few commits and patch changed according to Greg's comments. Regards Alex
==== >From 186c534b0b8b9649fbfce05b0b4f90f764c571a4 Mon Sep 17 00:00:00 2001 From: Alex Shi <[email protected]> Date: Tue, 16 Aug 2016 15:29:01 +0800 Subject: [PATCH 2/4] cpu: expose pm_qos_resume_latency for each cpu Adding /sys/devices/system/cpu/cpux/power/pm_qos_resume_latency_us for each of cpus. The pm_qos_resume_latency usage defined in Documentation/ABI/testing/sysfs-devices-power The cpu-dma PM QoS constraint impacts all the cpus in the system. There is no way to let the user to choose a PM QoS constraint per cpu. The following patch exposes to the userspace a per cpu based sysfs file in order to let the userspace to change the value of the PM QoS latency constraint. This change is inoperative in its form and the cpuidle governors have to take into account the per cpu latency constraint in addition to the global cpu-dma latency constraint in order to operate properly. Signed-off-by: Alex Shi <[email protected]> To: [email protected] To: Greg Kroah-Hartman <[email protected]> Cc: [email protected] Cc: Ulf Hansson <[email protected]> Cc: Daniel Lezcano <[email protected]> --- drivers/base/cpu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index 4c28e1a..2c3b359 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -17,6 +17,7 @@ #include <linux/of.h> #include <linux/cpufeature.h> #include <linux/tick.h> +#include <linux/pm_qos.h> #include "base.h" @@ -376,6 +377,7 @@ int register_cpu(struct cpu *cpu, int num) per_cpu(cpu_sys_devices, num) = &cpu->dev; register_cpu_under_node(num, cpu_to_node(num)); + dev_pm_qos_expose_latency_limit(&cpu->dev, 0); return 0; } -- 2.8.1.101.g72d917a
