diff options
Diffstat (limited to 'kernel/sched.c')
| -rw-r--r-- | kernel/sched.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index f6cf5cbc64ba..8b1b09686199 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -472,6 +472,10 @@ struct rq { #endif int skip_clock_update; + /* time-based average load */ + u64 nr_last_stamp; + unsigned int ave_nr_running; + /* capture load from *all* tasks on this cpu: */ struct load_weight load; unsigned long nr_load_updates; @@ -1756,13 +1760,40 @@ static const struct sched_class rt_sched_class; #include "sched_stats.h" +/* 27 ~= 134217728ns = 134.2ms + * 26 ~= 67108864ns = 67.1ms + * 25 ~= 33554432ns = 33.5ms + * 24 ~= 16777216ns = 16.8ms + */ +#define NR_AVE_PERIOD_EXP 27 +#define NR_AVE_SCALE(x) ((x) << FSHIFT) +#define NR_AVE_PERIOD (1 << NR_AVE_PERIOD_EXP) +#define NR_AVE_DIV_PERIOD(x) ((x) >> NR_AVE_PERIOD_EXP) + +static inline void do_avg_nr_running(struct rq *rq) +{ + s64 nr, deltax; + + deltax = rq->clock_task - rq->nr_last_stamp; + rq->nr_last_stamp = rq->clock_task; + nr = NR_AVE_SCALE(rq->nr_running); + + if (deltax > NR_AVE_PERIOD) + rq->ave_nr_running = nr; + else + rq->ave_nr_running += + NR_AVE_DIV_PERIOD(deltax * (nr - rq->ave_nr_running)); +} + static void inc_nr_running(struct rq *rq) { + do_avg_nr_running(rq); rq->nr_running++; } static void dec_nr_running(struct rq *rq) { + do_avg_nr_running(rq); rq->nr_running--; } @@ -3255,6 +3286,16 @@ unsigned long nr_iowait(void) return sum; } +unsigned long avg_nr_running(void) +{ + unsigned long i, sum = 0; + + for_each_online_cpu(i) + sum += cpu_rq(i)->ave_nr_running; + + return sum; +} + unsigned long nr_iowait_cpu(int cpu) { struct rq *this = cpu_rq(cpu); |