diff options
| author | Alex Shi <alex.shi@linaro.org> | 2016-08-05 17:13:27 +0800 |
|---|---|---|
| committer | Alex Shi <alex.shi@linaro.org> | 2016-08-17 16:30:44 +0800 |
| commit | 35d3f6053b6681de3514d4c8b1af8b1f4a562f10 (patch) | |
| tree | f479de07c932c3258dd91723ea7305cf32692798 | |
| parent | 5958e07ccd7bff08b27b07ec3c631c34e1242447 (diff) | |
cpuidle/menu: add per cpu pm_qos_resume_latency consideration
Kernel or user may have special requirement on cpu response time, like
if a interrupt is pinned to a cpu, we don't want the cpu goes too deep
sleep. This patch can prevent this thing happen by consider per cpu
resume_latency setting in cpu sleep state selection in menu governor.
According to sysfs-device ABI:Documentation/ABI/testing/sysfs-devices-power
the pm_qos_resume_latency ask device to give reponse in this time. That's
similar with cpu cstates' entry_latency + exit_latency. But since
most of cpu cstate either has no entry_latency or add it into exit_latency
So, we just can restrict this time requirement as states exit_latency.
Signed-off-by: Alex Shi <alex.shi@linaro.org>
| -rw-r--r-- | drivers/cpuidle/governors/menu.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index bb58e2a4ac52..e35488001a1f 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -12,6 +12,7 @@ #include <linux/kernel.h> #include <linux/cpuidle.h> +#include <linux/cpu.h> #include <linux/pm_qos.h> #include <linux/time.h> #include <linux/ktime.h> @@ -281,17 +282,23 @@ again: static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) { struct menu_device *data = this_cpu_ptr(&menu_devices); + struct device *device = get_cpu_device(dev->cpu); int latency_req = pm_qos_request(PM_QOS_CPU_DMA_LATENCY); int i; unsigned int interactivity_req; unsigned int expected_interval; unsigned long nr_iowaiters, cpu_load; + int resume_latency = dev_pm_qos_read_value(device); if (data->needs_update) { menu_update(drv, dev); data->needs_update = 0; } + /* resume_latency is 0 means no restriction */ + if (resume_latency && resume_latency < latency_req) + latency_req = resume_latency; + /* Special case when user has set very strict latency requirement */ if (unlikely(latency_req == 0)) return 0; |