diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched.c | 31 |
1 files changed, 14 insertions, 17 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 6225d3a9c8ee..c4ba3805a4fb 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -69,8 +69,6 @@ #define USER_PRIO(p) ((p)-MAX_RT_PRIO) #define TASK_USER_PRIO(p) USER_PRIO((p)->static_prio) #define MAX_USER_PRIO (USER_PRIO(MAX_PRIO)) -#define AVG_TIMESLICE (MIN_TIMESLICE + ((MAX_TIMESLICE - MIN_TIMESLICE) *\ - (MAX_PRIO-1-NICE_TO_PRIO(0))/(MAX_USER_PRIO - 1))) /* * Some helpers for converting nanosecond timing to jiffy resolution @@ -82,11 +80,11 @@ * These are the 'tuning knobs' of the scheduler: * * Minimum timeslice is 5 msecs (or 1 jiffy, whichever is larger), - * default timeslice is 100 msecs, maximum timeslice is 200 msecs. + * default timeslice is 100 msecs, maximum timeslice is 800 msecs. * Timeslices get refilled after they expire. */ #define MIN_TIMESLICE max(5 * HZ / 1000, 1) -#define MAX_TIMESLICE (200 * HZ / 1000) +#define DEF_TIMESLICE (100 * HZ / 1000) #define ON_RUNQUEUE_WEIGHT 30 #define CHILD_PENALTY 95 #define PARENT_PENALTY 100 @@ -94,7 +92,7 @@ #define PRIO_BONUS_RATIO 25 #define MAX_BONUS (MAX_USER_PRIO * PRIO_BONUS_RATIO / 100) #define INTERACTIVE_DELTA 2 -#define MAX_SLEEP_AVG (AVG_TIMESLICE * MAX_BONUS) +#define MAX_SLEEP_AVG (DEF_TIMESLICE * MAX_BONUS) #define STARVATION_LIMIT (MAX_SLEEP_AVG) #define NS_MAX_SLEEP_AVG (JIFFIES_TO_NS(MAX_SLEEP_AVG)) #define CREDIT_LIMIT 100 @@ -163,25 +161,24 @@ ((p)->prio < (rq)->curr->prio) /* - * BASE_TIMESLICE scales user-nice values [ -20 ... 19 ] - * to time slice values. + * task_timeslice() scales user-nice values [ -20 ... 0 ... 19 ] + * to time slice values: [800ms ... 100ms ... 5ms] * * The higher a thread's priority, the bigger timeslices * it gets during one round of execution. But even the lowest * priority thread gets MIN_TIMESLICE worth of execution time. - * - * task_timeslice() is the interface that is used by the scheduler. */ -#define BASE_TIMESLICE(p) \ - max(MAX_TIMESLICE * (MAX_PRIO - (p)->static_prio) / (MAX_USER_PRIO), \ - MIN_TIMESLICE) +#define SCALE_PRIO(x, prio) \ + max(x * (MAX_PRIO - prio) / (MAX_USER_PRIO/2), MIN_TIMESLICE) static unsigned int task_timeslice(task_t *p) { - return BASE_TIMESLICE(p); + if (p->static_prio < NICE_TO_PRIO(0)) + return SCALE_PRIO(DEF_TIMESLICE*4, p->static_prio); + else + return SCALE_PRIO(DEF_TIMESLICE, p->static_prio); } - #define task_hot(p, now, sd) ((now) - (p)->timestamp < (sd)->cache_hot_time) enum idle_type @@ -792,7 +789,7 @@ static void recalc_task_prio(task_t *p, unsigned long long now) if (p->mm && p->activated != -1 && sleep_time > INTERACTIVE_SLEEP(p)) { p->sleep_avg = JIFFIES_TO_NS(MAX_SLEEP_AVG - - AVG_TIMESLICE); + DEF_TIMESLICE); if (!HIGH_CREDIT(p)) p->interactive_credit++; } else { @@ -1434,8 +1431,8 @@ void fastcall sched_exit(task_t * p) rq = task_rq_lock(p->parent, &flags); if (p->first_time_slice) { p->parent->time_slice += p->time_slice; - if (unlikely(p->parent->time_slice > MAX_TIMESLICE)) - p->parent->time_slice = MAX_TIMESLICE; + if (unlikely(p->parent->time_slice > task_timeslice(p))) + p->parent->time_slice = task_timeslice(p); } if (p->sleep_avg < p->parent->sleep_avg) p->parent->sleep_avg = p->parent->sleep_avg / |