diff options
Diffstat (limited to 'kernel/sched/core.c')
-rw-r--r-- | kernel/sched/core.c | 76 |
1 files changed, 41 insertions, 35 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 82ad284f823..8c38b5e7ce4 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3142,6 +3142,20 @@ void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st) # define nsecs_to_cputime(__nsecs) nsecs_to_jiffies(__nsecs) #endif +static cputime_t scale_utime(cputime_t utime, cputime_t rtime, cputime_t total) +{ + u64 temp = (__force u64) rtime; + + temp *= (__force u64) utime; + + if (sizeof(cputime_t) == 4) + temp = div_u64(temp, (__force u32) total); + else + temp = div64_u64(temp, (__force u64) total); + + return (__force cputime_t) temp; +} + void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st) { cputime_t rtime, utime = p->utime, total = utime + p->stime; @@ -3151,13 +3165,9 @@ void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st) */ rtime = nsecs_to_cputime(p->se.sum_exec_runtime); - if (total) { - u64 temp = (__force u64) rtime; - - temp *= (__force u64) utime; - do_div(temp, (__force u32) total); - utime = (__force cputime_t) temp; - } else + if (total) + utime = scale_utime(utime, rtime, total); + else utime = rtime; /* @@ -3184,13 +3194,9 @@ void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st) total = cputime.utime + cputime.stime; rtime = nsecs_to_cputime(cputime.sum_exec_runtime); - if (total) { - u64 temp = (__force u64) rtime; - - temp *= (__force u64) cputime.utime; - do_div(temp, (__force u32) total); - utime = (__force cputime_t) temp; - } else + if (total) + utime = scale_utime(cputime.utime, rtime, total); + else utime = rtime; sig->prev_utime = max(sig->prev_utime, utime); @@ -5298,27 +5304,17 @@ void idle_task_exit(void) } /* - * While a dead CPU has no uninterruptible tasks queued at this point, - * it might still have a nonzero ->nr_uninterruptible counter, because - * for performance reasons the counter is not stricly tracking tasks to - * their home CPUs. So we just add the counter to another CPU's counter, - * to keep the global sum constant after CPU-down: - */ -static void migrate_nr_uninterruptible(struct rq *rq_src) -{ - struct rq *rq_dest = cpu_rq(cpumask_any(cpu_active_mask)); - - rq_dest->nr_uninterruptible += rq_src->nr_uninterruptible; - rq_src->nr_uninterruptible = 0; -} - -/* - * remove the tasks which were accounted by rq from calc_load_tasks. + * Since this CPU is going 'away' for a while, fold any nr_active delta + * we might have. Assumes we're called after migrate_tasks() so that the + * nr_active count is stable. + * + * Also see the comment "Global load-average calculations". */ -static void calc_global_load_remove(struct rq *rq) +static void calc_load_migrate(struct rq *rq) { - atomic_long_sub(rq->calc_load_active, &calc_load_tasks); - rq->calc_load_active = 0; + long delta = calc_load_fold_active(rq); + if (delta) + atomic_long_add(delta, &calc_load_tasks); } /* @@ -5611,9 +5607,18 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) migrate_tasks(cpu); BUG_ON(rq->nr_running != 1); /* the migration thread */ raw_spin_unlock_irqrestore(&rq->lock, flags); + break; - migrate_nr_uninterruptible(rq); - calc_global_load_remove(rq); + case CPU_DEAD: + { + struct rq *dest_rq; + + local_irq_save(flags); + dest_rq = cpu_rq(smp_processor_id()); + raw_spin_lock(&dest_rq->lock); + calc_load_migrate(rq); + raw_spin_unlock_irqrestore(&dest_rq->lock, flags); + } break; #endif } @@ -7246,6 +7251,7 @@ int in_sched_functions(unsigned long addr) #ifdef CONFIG_CGROUP_SCHED struct task_group root_task_group; +LIST_HEAD(task_groups); #endif DECLARE_PER_CPU(cpumask_var_t, load_balance_tmpmask); |