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| author | venkatesh.pallipadi@intel.com <venkatesh.pallipadi@intel.com> | 2008-08-04 20:59:11 +0200 |
|---|---|---|
| committer | Dave Jones <davej@redhat.com> | 2008-10-09 19:52:44 +0200 |
| commit | 8083e4ad970e4eb567e31037060cdd4ba346f0c0 (patch) | |
| tree | 330e6dc1dbb7c7db13d14f3681d4a51f62708329 /kernel/time/tick-sched.c | |
| parent | [CPUFREQ][4/6] cpufreq_ondemand: Parameterize down differential (diff) | |
| download | linux-8083e4ad970e4eb567e31037060cdd4ba346f0c0.tar.xz linux-8083e4ad970e4eb567e31037060cdd4ba346f0c0.zip | |
[CPUFREQ][5/6] cpufreq: Changes to get_cpu_idle_time_us(), used by ondemand governor
export get_cpu_idle_time_us() for it to be used in ondemand governor.
Last update time can be current time when the CPU is currently non-idle,
accounting for the busy time since last idle.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Diffstat (limited to 'kernel/time/tick-sched.c')
| -rw-r--r-- | kernel/time/tick-sched.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index cb02324bdb88..a4d219398167 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -20,6 +20,7 @@ #include <linux/profile.h> #include <linux/sched.h> #include <linux/tick.h> +#include <linux/module.h> #include <asm/irq_regs.h> @@ -190,9 +191,17 @@ u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time) { struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); - *last_update_time = ktime_to_us(ts->idle_lastupdate); + if (!tick_nohz_enabled) + return -1; + + if (ts->idle_active) + *last_update_time = ktime_to_us(ts->idle_lastupdate); + else + *last_update_time = ktime_to_us(ktime_get()); + return ktime_to_us(ts->idle_sleeptime); } +EXPORT_SYMBOL_GPL(get_cpu_idle_time_us); /** * tick_nohz_stop_sched_tick - stop the idle tick from the idle task |