diff options
| author | Mel Gorman <mgorman@suse.de> | 2014-08-06 14:19:21 +0100 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2014-08-06 21:17:45 +0200 |
| commit | 372ba8cb46b271a7662b92cbefedee56725f6bd0 (patch) | |
| tree | 536013552cd845b4eb0559dc79c023ecc426c21e /drivers/cpuidle/governors/menu.c | |
| parent | 64b4ca5cb6e1a9f577588db5765dc996ddf595e1 (diff) | |
| download | lwn-372ba8cb46b271a7662b92cbefedee56725f6bd0.tar.gz lwn-372ba8cb46b271a7662b92cbefedee56725f6bd0.zip | |
cpuidle: menu: Lookup CPU runqueues less
The menu governer makes separate lookups of the CPU runqueue to get
load and number of IO waiters but it can be done with a single lookup.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/cpuidle/governors/menu.c')
| -rw-r--r-- | drivers/cpuidle/governors/menu.c | 17 |
1 files changed, 7 insertions, 10 deletions
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index f55d8260ec43..27702742b319 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -134,12 +134,9 @@ struct menu_device { #define LOAD_INT(x) ((x) >> FSHIFT) #define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100) -static int get_loadavg(void) +static inline int get_loadavg(unsigned long load) { - unsigned long this = this_cpu_load(); - - - return LOAD_INT(this) * 10 + LOAD_FRAC(this) / 10; + return LOAD_INT(load) * 10 + LOAD_FRAC(load) / 10; } static inline int which_bucket(unsigned int duration, unsigned long nr_iowaiters) @@ -175,13 +172,13 @@ static inline int which_bucket(unsigned int duration, unsigned long nr_iowaiters * to be, the higher this multiplier, and thus the higher * the barrier to go to an expensive C state. */ -static inline int performance_multiplier(unsigned long nr_iowaiters) +static inline int performance_multiplier(unsigned long nr_iowaiters, unsigned long load) { int mult = 1; /* for higher loadavg, we are more reluctant */ - mult += 2 * get_loadavg(); + mult += 2 * get_loadavg(load); /* for IO wait tasks (per cpu!) we add 5x each */ mult += 10 * nr_iowaiters; @@ -296,7 +293,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) int latency_req = pm_qos_request(PM_QOS_CPU_DMA_LATENCY); int i; unsigned int interactivity_req; - unsigned long nr_iowaiters; + unsigned long nr_iowaiters, cpu_load; if (data->needs_update) { menu_update(drv, dev); @@ -312,7 +309,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) /* determine the expected residency time, round up */ data->next_timer_us = ktime_to_us(tick_nohz_get_sleep_length()); - nr_iowaiters = nr_iowait_cpu(smp_processor_id()); + get_iowait_load(&nr_iowaiters, &cpu_load); data->bucket = which_bucket(data->next_timer_us, nr_iowaiters); /* @@ -331,7 +328,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) * duration / latency ratio. Adjust the latency limit if * necessary. */ - interactivity_req = data->predicted_us / performance_multiplier(nr_iowaiters); + interactivity_req = data->predicted_us / performance_multiplier(nr_iowaiters, cpu_load); if (latency_req > interactivity_req) latency_req = interactivity_req; |