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-rw-r--r--kernel/sched.c112
1 files changed, 72 insertions, 40 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 45e17b83b7f1..6107a0cd6325 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -262,7 +262,8 @@ struct rq {
s64 clock_max_delta;
unsigned int clock_warps, clock_overflows;
- unsigned int clock_unstable_events;
+ u64 idle_clock;
+ unsigned int clock_deep_idle_events;
u64 tick_timestamp;
atomic_t nr_iowait;
@@ -556,18 +557,40 @@ static inline struct rq *this_rq_lock(void)
}
/*
- * CPU frequency is/was unstable - start new by setting prev_clock_raw:
+ * We are going deep-idle (irqs are disabled):
*/
-void sched_clock_unstable_event(void)
+void sched_clock_idle_sleep_event(void)
{
- unsigned long flags;
- struct rq *rq;
+ struct rq *rq = cpu_rq(smp_processor_id());
- rq = task_rq_lock(current, &flags);
- rq->prev_clock_raw = sched_clock();
- rq->clock_unstable_events++;
- task_rq_unlock(rq, &flags);
+ spin_lock(&rq->lock);
+ __update_rq_clock(rq);
+ spin_unlock(&rq->lock);
+ rq->clock_deep_idle_events++;
+}
+EXPORT_SYMBOL_GPL(sched_clock_idle_sleep_event);
+
+/*
+ * We just idled delta nanoseconds (called with irqs disabled):
+ */
+void sched_clock_idle_wakeup_event(u64 delta_ns)
+{
+ struct rq *rq = cpu_rq(smp_processor_id());
+ u64 now = sched_clock();
+
+ rq->idle_clock += delta_ns;
+ /*
+ * Override the previous timestamp and ignore all
+ * sched_clock() deltas that occured while we idled,
+ * and use the PM-provided delta_ns to advance the
+ * rq clock:
+ */
+ spin_lock(&rq->lock);
+ rq->prev_clock_raw = now;
+ rq->clock += delta_ns;
+ spin_unlock(&rq->lock);
}
+EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event);
/*
* resched_task - mark a task 'to be rescheduled now'.
@@ -645,7 +668,7 @@ static u64 div64_likely32(u64 divident, unsigned long divisor)
/*
* Shift right and round:
*/
-#define RSR(x, y) (((x) + (1UL << ((y) - 1))) >> (y))
+#define SRR(x, y) (((x) + (1UL << ((y) - 1))) >> (y))
static unsigned long
calc_delta_mine(unsigned long delta_exec, unsigned long weight,
@@ -661,10 +684,10 @@ calc_delta_mine(unsigned long delta_exec, unsigned long weight,
* Check whether we'd overflow the 64-bit multiplication:
*/
if (unlikely(tmp > WMULT_CONST))
- tmp = RSR(RSR(tmp, WMULT_SHIFT/2) * lw->inv_weight,
+ tmp = SRR(SRR(tmp, WMULT_SHIFT/2) * lw->inv_weight,
WMULT_SHIFT/2);
else
- tmp = RSR(tmp * lw->inv_weight, WMULT_SHIFT);
+ tmp = SRR(tmp * lw->inv_weight, WMULT_SHIFT);
return (unsigned long)min(tmp, (u64)(unsigned long)LONG_MAX);
}
@@ -835,7 +858,6 @@ static void dec_nr_running(struct task_struct *p, struct rq *rq)
static void set_load_weight(struct task_struct *p)
{
- task_rq(p)->cfs.wait_runtime -= p->se.wait_runtime;
p->se.wait_runtime = 0;
if (task_has_rt_policy(p)) {
@@ -1564,6 +1586,7 @@ static void __sched_fork(struct task_struct *p)
p->se.wait_start_fair = 0;
p->se.exec_start = 0;
p->se.sum_exec_runtime = 0;
+ p->se.prev_sum_exec_runtime = 0;
p->se.delta_exec = 0;
p->se.delta_fair_run = 0;
p->se.delta_fair_sleep = 0;
@@ -1659,6 +1682,11 @@ void fastcall wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
p->prio = effective_prio(p);
+ if (rt_prio(p->prio))
+ p->sched_class = &rt_sched_class;
+ else
+ p->sched_class = &fair_sched_class;
+
if (!p->sched_class->task_new || !sysctl_sched_child_runs_first ||
(clone_flags & CLONE_VM) || task_cpu(p) != this_cpu ||
!current->se.on_rq) {
@@ -2157,12 +2185,6 @@ int can_migrate_task(struct task_struct *p, struct rq *rq, int this_cpu,
if (task_running(rq, p))
return 0;
- /*
- * Aggressive migration if too many balance attempts have failed:
- */
- if (sd->nr_balance_failed > sd->cache_nice_tries)
- return 1;
-
return 1;
}
@@ -2494,7 +2516,7 @@ group_next:
* a think about bumping its value to force at least one task to be
* moved
*/
- if (*imbalance + SCHED_LOAD_SCALE_FUZZ < busiest_load_per_task/2) {
+ if (*imbalance < busiest_load_per_task) {
unsigned long tmp, pwr_now, pwr_move;
unsigned int imbn;
@@ -2546,10 +2568,8 @@ small_imbalance:
pwr_move /= SCHED_LOAD_SCALE;
/* Move if we gain throughput */
- if (pwr_move <= pwr_now)
- goto out_balanced;
-
- *imbalance = busiest_load_per_task;
+ if (pwr_move > pwr_now)
+ *imbalance = busiest_load_per_task;
}
return busiest;
@@ -3020,6 +3040,7 @@ static inline void rebalance_domains(int cpu, enum cpu_idle_type idle)
struct sched_domain *sd;
/* Earliest time when we have to do rebalance again */
unsigned long next_balance = jiffies + 60*HZ;
+ int update_next_balance = 0;
for_each_domain(cpu, sd) {
if (!(sd->flags & SD_LOAD_BALANCE))
@@ -3056,8 +3077,10 @@ static inline void rebalance_domains(int cpu, enum cpu_idle_type idle)
if (sd->flags & SD_SERIALIZE)
spin_unlock(&balancing);
out:
- if (time_after(next_balance, sd->last_balance + interval))
+ if (time_after(next_balance, sd->last_balance + interval)) {
next_balance = sd->last_balance + interval;
+ update_next_balance = 1;
+ }
/*
* Stop the load balance at this level. There is another
@@ -3067,7 +3090,14 @@ out:
if (!balance)
break;
}
- rq->next_balance = next_balance;
+
+ /*
+ * next_balance will be updated only when there is a need.
+ * When the cpu is attached to null domain for ex, it will not be
+ * updated.
+ */
+ if (likely(update_next_balance))
+ rq->next_balance = next_balance;
}
/*
@@ -4525,10 +4555,7 @@ asmlinkage long sys_sched_yield(void)
struct rq *rq = this_rq_lock();
schedstat_inc(rq, yld_cnt);
- if (unlikely(rq->nr_running == 1))
- schedstat_inc(rq, yld_act_empty);
- else
- current->sched_class->yield_task(rq, current);
+ current->sched_class->yield_task(rq, current);
/*
* Since we are going to call schedule() anyway, there's
@@ -4884,14 +4911,18 @@ cpumask_t nohz_cpu_mask = CPU_MASK_NONE;
static inline void sched_init_granularity(void)
{
unsigned int factor = 1 + ilog2(num_online_cpus());
- const unsigned long gran_limit = 100000000;
+ const unsigned long limit = 100000000;
+
+ sysctl_sched_min_granularity *= factor;
+ if (sysctl_sched_min_granularity > limit)
+ sysctl_sched_min_granularity = limit;
- sysctl_sched_granularity *= factor;
- if (sysctl_sched_granularity > gran_limit)
- sysctl_sched_granularity = gran_limit;
+ sysctl_sched_latency *= factor;
+ if (sysctl_sched_latency > limit)
+ sysctl_sched_latency = limit;
- sysctl_sched_runtime_limit = sysctl_sched_granularity * 4;
- sysctl_sched_wakeup_granularity = sysctl_sched_granularity / 2;
+ sysctl_sched_runtime_limit = sysctl_sched_latency;
+ sysctl_sched_wakeup_granularity = sysctl_sched_min_granularity / 2;
}
#ifdef CONFIG_SMP
@@ -5234,15 +5265,16 @@ static void migrate_dead_tasks(unsigned int dead_cpu)
static struct ctl_table sd_ctl_dir[] = {
{
.procname = "sched_domain",
- .mode = 0755,
+ .mode = 0555,
},
{0,},
};
static struct ctl_table sd_ctl_root[] = {
{
+ .ctl_name = CTL_KERN,
.procname = "kernel",
- .mode = 0755,
+ .mode = 0555,
.child = sd_ctl_dir,
},
{0,},
@@ -5318,7 +5350,7 @@ static ctl_table *sd_alloc_ctl_cpu_table(int cpu)
for_each_domain(cpu, sd) {
snprintf(buf, 32, "domain%d", i);
entry->procname = kstrdup(buf, GFP_KERNEL);
- entry->mode = 0755;
+ entry->mode = 0555;
entry->child = sd_alloc_ctl_domain_table(sd);
entry++;
i++;
@@ -5338,7 +5370,7 @@ static void init_sched_domain_sysctl(void)
for (i = 0; i < cpu_num; i++, entry++) {
snprintf(buf, 32, "cpu%d", i);
entry->procname = kstrdup(buf, GFP_KERNEL);
- entry->mode = 0755;
+ entry->mode = 0555;
entry->child = sd_alloc_ctl_cpu_table(i);
}
sd_sysctl_header = register_sysctl_table(sd_ctl_root);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-18 15:12:58 +0100