* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: disable the hrtick for now
sched: revert back to per-rq vruntime
sched: fair scheduler should not resched rt tasks
sched: optimize group load balancer
sched: minor fast-path overhead reduction
sched: fix the wrong mask_len, cleanup
sched: kill unused scheduler decl.
sched: fix the wrong mask_len
sched: only update rq->clock while holding rq->lock
extern void account_process_tick(struct task_struct *task, int user);
extern void update_process_times(int user);
extern void scheduler_tick(void);
-extern void hrtick_resched(void);
extern void sched_show_task(struct task_struct *p);
extern unsigned int sysctl_sched_migration_cost;
extern unsigned int sysctl_sched_nr_migrate;
extern unsigned int sysctl_sched_shares_ratelimit;
+extern unsigned int sysctl_sched_shares_thresh;
int sched_nr_latency_handler(struct ctl_table *table, int write,
struct file *file, void __user *buffer, size_t *length,
unsigned int sysctl_sched_shares_ratelimit = 250000;
/*
+ * Inject some fuzzyness into changing the per-cpu group shares
+ * this avoids remote rq-locks at the expense of fairness.
+ * default: 4
+ */
+unsigned int sysctl_sched_shares_thresh = 4;
+
+/*
* period over which we measure -rt task cpu usage in us.
* default: 1s
*/
* Calculate and set the cpu's group shares.
*/
static void
-__update_group_shares_cpu(struct task_group *tg, int cpu,
- unsigned long sd_shares, unsigned long sd_rq_weight)
+update_group_shares_cpu(struct task_group *tg, int cpu,
+ unsigned long sd_shares, unsigned long sd_rq_weight)
{
int boost = 0;
unsigned long shares;
*
*/
shares = (sd_shares * rq_weight) / (sd_rq_weight + 1);
+ shares = clamp_t(unsigned long, shares, MIN_SHARES, MAX_SHARES);
- /*
- * record the actual number of shares, not the boosted amount.
- */
- tg->cfs_rq[cpu]->shares = boost ? 0 : shares;
- tg->cfs_rq[cpu]->rq_weight = rq_weight;
+ if (abs(shares - tg->se[cpu]->load.weight) >
+ sysctl_sched_shares_thresh) {
+ struct rq *rq = cpu_rq(cpu);
+ unsigned long flags;
- if (shares < MIN_SHARES)
- shares = MIN_SHARES;
- else if (shares > MAX_SHARES)
- shares = MAX_SHARES;
+ spin_lock_irqsave(&rq->lock, flags);
+ /*
+ * record the actual number of shares, not the boosted amount.
+ */
+ tg->cfs_rq[cpu]->shares = boost ? 0 : shares;
+ tg->cfs_rq[cpu]->rq_weight = rq_weight;
- __set_se_shares(tg->se[cpu], shares);
+ __set_se_shares(tg->se[cpu], shares);
+ spin_unlock_irqrestore(&rq->lock, flags);
+ }
}
/*
if (!rq_weight)
rq_weight = cpus_weight(sd->span) * NICE_0_LOAD;
- for_each_cpu_mask(i, sd->span) {
- struct rq *rq = cpu_rq(i);
- unsigned long flags;
-
- spin_lock_irqsave(&rq->lock, flags);
- __update_group_shares_cpu(tg, i, shares, rq_weight);
- spin_unlock_irqrestore(&rq->lock, flags);
- }
+ for_each_cpu_mask(i, sd->span)
+ update_group_shares_cpu(tg, i, shares, rq_weight);
return 0;
}
if (sched_feat(HRTICK))
hrtick_clear(rq);
- /*
- * Do the rq-clock update outside the rq lock:
- */
- local_irq_disable();
+ spin_lock_irq(&rq->lock);
update_rq_clock(rq);
- spin_lock(&rq->lock);
clear_tsk_need_resched(prev);
if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
const_debug unsigned int sysctl_sched_migration_cost = 500000UL;
+static const struct sched_class fair_sched_class;
+
/**************************************************************
* CFS operations on generic schedulable entities:
*/
#endif
/*
- * delta *= w / rw
+ * delta *= P[w / rw]
*/
static inline unsigned long
calc_delta_weight(unsigned long delta, struct sched_entity *se)
}
/*
- * delta *= rw / w
+ * delta /= w
*/
static inline unsigned long
calc_delta_fair(unsigned long delta, struct sched_entity *se)
{
- for_each_sched_entity(se) {
- delta = calc_delta_mine(delta,
- cfs_rq_of(se)->load.weight, &se->load);
- }
+ if (unlikely(se->load.weight != NICE_0_LOAD))
+ delta = calc_delta_mine(delta, NICE_0_LOAD, &se->load);
return delta;
}
* We calculate the wall-time slice from the period by taking a part
* proportional to the weight.
*
- * s = p*w/rw
+ * s = p*P[w/rw]
*/
static u64 sched_slice(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- return calc_delta_weight(__sched_period(cfs_rq->nr_running), se);
+ unsigned long nr_running = cfs_rq->nr_running;
+
+ if (unlikely(!se->on_rq))
+ nr_running++;
+
+ return calc_delta_weight(__sched_period(nr_running), se);
}
/*
* We calculate the vruntime slice of a to be inserted task
*
- * vs = s*rw/w = p
+ * vs = s/w
*/
-static u64 sched_vslice_add(struct cfs_rq *cfs_rq, struct sched_entity *se)
+static u64 sched_vslice(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- unsigned long nr_running = cfs_rq->nr_running;
-
- if (!se->on_rq)
- nr_running++;
-
- return __sched_period(nr_running);
+ return calc_delta_fair(sched_slice(cfs_rq, se), se);
}
/*
* stays open at the end.
*/
if (initial && sched_feat(START_DEBIT))
- vruntime += sched_vslice_add(cfs_rq, se);
+ vruntime += sched_vslice(cfs_rq, se);
if (!initial) {
/* sleeps upto a single latency don't count. */
struct rq *rq = rq_of(cfs_rq);
u64 pair_slice = rq->clock - cfs_rq->pair_start;
- if (!cfs_rq->next || pair_slice > sched_slice(cfs_rq, cfs_rq->next)) {
+ if (!cfs_rq->next || pair_slice > sysctl_sched_min_granularity) {
cfs_rq->pair_start = rq->clock;
return se;
}
hrtick_start(rq, delta);
}
}
+
+/*
+ * called from enqueue/dequeue and updates the hrtick when the
+ * current task is from our class and nr_running is low enough
+ * to matter.
+ */
+static void hrtick_update(struct rq *rq)
+{
+ struct task_struct *curr = rq->curr;
+
+ if (curr->sched_class != &fair_sched_class)
+ return;
+
+ if (cfs_rq_of(&curr->se)->nr_running < sched_nr_latency)
+ hrtick_start_fair(rq, curr);
+}
#else /* !CONFIG_SCHED_HRTICK */
static inline void
hrtick_start_fair(struct rq *rq, struct task_struct *p)
{
}
+
+static inline void hrtick_update(struct rq *rq)
+{
+}
#endif
/*
wakeup = 1;
}
- hrtick_start_fair(rq, rq->curr);
+ hrtick_update(rq);
}
/*
sleep = 1;
}
- hrtick_start_fair(rq, rq->curr);
+ hrtick_update(rq);
}
/*
#ifdef CONFIG_SMP
-static const struct sched_class fair_sched_class;
-
#ifdef CONFIG_FAIR_GROUP_SCHED
/*
* effective_load() calculates the load change as seen from the root_task_group
SCHED_FEAT(AFFINE_WAKEUPS, 1)
SCHED_FEAT(CACHE_HOT_BUDDY, 1)
SCHED_FEAT(SYNC_WAKEUPS, 1)
-SCHED_FEAT(HRTICK, 1)
+SCHED_FEAT(HRTICK, 0)
SCHED_FEAT(DOUBLE_TICK, 0)
SCHED_FEAT(ASYM_GRAN, 1)
SCHED_FEAT(LB_BIAS, 1)
static int show_schedstat(struct seq_file *seq, void *v)
{
int cpu;
- int mask_len = NR_CPUS/32 * 9;
+ int mask_len = DIV_ROUND_UP(NR_CPUS, 32) * 9;
char *mask_str = kmalloc(mask_len, GFP_KERNEL);
if (mask_str == NULL)
},
{
.ctl_name = CTL_UNNUMBERED,
+ .procname = "sched_shares_thresh",
+ .data = &sysctl_sched_shares_thresh,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec_minmax,
+ .strategy = &sysctl_intvec,
+ .extra1 = &zero,
+ },
+ {
+ .ctl_name = CTL_UNNUMBERED,
.procname = "sched_child_runs_first",
.data = &sysctl_sched_child_runs_first,
.maxlen = sizeof(unsigned int),
projects / platform / kernel / linux-rpi.git / commitdiff