diff options
Diffstat (limited to 'kernel/sched.c')
| -rw-r--r-- | kernel/sched.c | 27 |
1 files changed, 19 insertions, 8 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index cca93cc0dd7..08f86178aa3 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -57,6 +57,16 @@ #include <asm/unistd.h> /* + * Scheduler clock - returns current time in nanosec units. + * This is default implementation. + * Architectures and sub-architectures can override this. + */ +unsigned long long __attribute__((weak)) sched_clock(void) +{ + return (unsigned long long)jiffies * (1000000000 / HZ); +} + +/* * Convert user-nice values [ -20 ... 0 ... 19 ] * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ], * and back. @@ -2887,14 +2897,16 @@ static void active_load_balance(struct rq *busiest_rq, int busiest_cpu) static void update_load(struct rq *this_rq) { unsigned long this_load; - int i, scale; + unsigned int i, scale; this_load = this_rq->raw_weighted_load; /* Update our load: */ - for (i = 0, scale = 1; i < 3; i++, scale <<= 1) { + for (i = 0, scale = 1; i < 3; i++, scale += scale) { unsigned long old_load, new_load; + /* scale is effectively 1 << i now, and >> i divides by scale */ + old_load = this_rq->cpu_load[i]; new_load = this_load; /* @@ -2904,7 +2916,7 @@ static void update_load(struct rq *this_rq) */ if (new_load > old_load) new_load += scale-1; - this_rq->cpu_load[i] = (old_load*(scale-1) + new_load) / scale; + this_rq->cpu_load[i] = (old_load*(scale-1) + new_load) >> i; } } @@ -4193,13 +4205,12 @@ static void __setscheduler(struct task_struct *p, int policy, int prio) } /** - * sched_setscheduler - change the scheduling policy and/or RT priority of - * a thread. + * sched_setscheduler - change the scheduling policy and/or RT priority of a thread. * @p: the task in question. * @policy: new policy. * @param: structure containing the new RT priority. * - * NOTE: the task may be already dead + * NOTE that the task may be already dead. */ int sched_setscheduler(struct task_struct *p, int policy, struct sched_param *param) @@ -4567,7 +4578,7 @@ asmlinkage long sys_sched_getaffinity(pid_t pid, unsigned int len, /** * sys_sched_yield - yield the current processor to other threads. * - * this function yields the current CPU by moving the calling thread + * This function yields the current CPU by moving the calling thread * to the expired array. If there are no other threads running on this * CPU then this function will return. */ @@ -4694,7 +4705,7 @@ EXPORT_SYMBOL(cond_resched_softirq); /** * yield - yield the current processor to other threads. * - * this is a shortcut for kernel-space yielding - it marks the + * This is a shortcut for kernel-space yielding - it marks the * thread runnable and calls sys_sched_yield(). */ void __sched yield(void) |