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-rw-r--r--kernel/sched/core.c28
-rw-r--r--kernel/sched/deadline.c40
-rw-r--r--kernel/sched/fair.c44
-rw-r--r--kernel/sched/idle.c9
-rw-r--r--kernel/sched/rt.c37
-rw-r--r--kernel/sched/sched.h30
-rw-r--r--kernel/sched/stop_task.c18
7 files changed, 136 insertions, 70 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index dd05a378631a..44123b4d14e8 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1065,7 +1065,7 @@ uclamp_update_active(struct task_struct *p, enum uclamp_id clamp_id)
* affecting a valid clamp bucket, the next time it's enqueued,
* it will already see the updated clamp bucket value.
*/
- if (!p->uclamp[clamp_id].active) {
+ if (p->uclamp[clamp_id].active) {
uclamp_rq_dec_id(rq, p, clamp_id);
uclamp_rq_inc_id(rq, p, clamp_id);
}
@@ -1073,6 +1073,7 @@ uclamp_update_active(struct task_struct *p, enum uclamp_id clamp_id)
task_rq_unlock(rq, p, &rf);
}
+#ifdef CONFIG_UCLAMP_TASK_GROUP
static inline void
uclamp_update_active_tasks(struct cgroup_subsys_state *css,
unsigned int clamps)
@@ -1091,7 +1092,6 @@ uclamp_update_active_tasks(struct cgroup_subsys_state *css,
css_task_iter_end(&it);
}
-#ifdef CONFIG_UCLAMP_TASK_GROUP
static void cpu_util_update_eff(struct cgroup_subsys_state *css);
static void uclamp_update_root_tg(void)
{
@@ -3929,13 +3929,22 @@ pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
}
restart:
+#ifdef CONFIG_SMP
/*
- * Ensure that we put DL/RT tasks before the pick loop, such that they
- * can PULL higher prio tasks when we lower the RQ 'priority'.
+ * We must do the balancing pass before put_next_task(), such
+ * that when we release the rq->lock the task is in the same
+ * state as before we took rq->lock.
+ *
+ * We can terminate the balance pass as soon as we know there is
+ * a runnable task of @class priority or higher.
*/
- prev->sched_class->put_prev_task(rq, prev, rf);
- if (!rq->nr_running)
- newidle_balance(rq, rf);
+ for_class_range(class, prev->sched_class, &idle_sched_class) {
+ if (class->balance(rq, prev, rf))
+ break;
+ }
+#endif
+
+ put_prev_task(rq, prev);
for_each_class(class) {
p = class->pick_next_task(rq, NULL, NULL);
@@ -6010,10 +6019,11 @@ void init_idle(struct task_struct *idle, int cpu)
struct rq *rq = cpu_rq(cpu);
unsigned long flags;
+ __sched_fork(0, idle);
+
raw_spin_lock_irqsave(&idle->pi_lock, flags);
raw_spin_lock(&rq->lock);
- __sched_fork(0, idle);
idle->state = TASK_RUNNING;
idle->se.exec_start = sched_clock();
idle->flags |= PF_IDLE;
@@ -6201,7 +6211,7 @@ static struct task_struct *__pick_migrate_task(struct rq *rq)
for_each_class(class) {
next = class->pick_next_task(rq, NULL, NULL);
if (next) {
- next->sched_class->put_prev_task(rq, next, NULL);
+ next->sched_class->put_prev_task(rq, next);
return next;
}
}
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 2dc48720f189..a8a08030a8f7 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -1691,6 +1691,22 @@ static void check_preempt_equal_dl(struct rq *rq, struct task_struct *p)
resched_curr(rq);
}
+static int balance_dl(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
+{
+ if (!on_dl_rq(&p->dl) && need_pull_dl_task(rq, p)) {
+ /*
+ * This is OK, because current is on_cpu, which avoids it being
+ * picked for load-balance and preemption/IRQs are still
+ * disabled avoiding further scheduler activity on it and we've
+ * not yet started the picking loop.
+ */
+ rq_unpin_lock(rq, rf);
+ pull_dl_task(rq);
+ rq_repin_lock(rq, rf);
+ }
+
+ return sched_stop_runnable(rq) || sched_dl_runnable(rq);
+}
#endif /* CONFIG_SMP */
/*
@@ -1758,45 +1774,28 @@ static struct task_struct *
pick_next_task_dl(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
{
struct sched_dl_entity *dl_se;
+ struct dl_rq *dl_rq = &rq->dl;
struct task_struct *p;
- struct dl_rq *dl_rq;
WARN_ON_ONCE(prev || rf);
- dl_rq = &rq->dl;
-
- if (unlikely(!dl_rq->dl_nr_running))
+ if (!sched_dl_runnable(rq))
return NULL;
dl_se = pick_next_dl_entity(rq, dl_rq);
BUG_ON(!dl_se);
-
p = dl_task_of(dl_se);
-
set_next_task_dl(rq, p);
-
return p;
}
-static void put_prev_task_dl(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
+static void put_prev_task_dl(struct rq *rq, struct task_struct *p)
{
update_curr_dl(rq);
update_dl_rq_load_avg(rq_clock_pelt(rq), rq, 1);
if (on_dl_rq(&p->dl) && p->nr_cpus_allowed > 1)
enqueue_pushable_dl_task(rq, p);
-
- if (rf && !on_dl_rq(&p->dl) && need_pull_dl_task(rq, p)) {
- /*
- * This is OK, because current is on_cpu, which avoids it being
- * picked for load-balance and preemption/IRQs are still
- * disabled avoiding further scheduler activity on it and we've
- * not yet started the picking loop.
- */
- rq_unpin_lock(rq, rf);
- pull_dl_task(rq);
- rq_repin_lock(rq, rf);
- }
}
/*
@@ -2442,6 +2441,7 @@ const struct sched_class dl_sched_class = {
.set_next_task = set_next_task_dl,
#ifdef CONFIG_SMP
+ .balance = balance_dl,
.select_task_rq = select_task_rq_dl,
.migrate_task_rq = migrate_task_rq_dl,
.set_cpus_allowed = set_cpus_allowed_dl,
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 682a754ea3e1..69a81a5709ff 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -6570,6 +6570,15 @@ static void task_dead_fair(struct task_struct *p)
{
remove_entity_load_avg(&p->se);
}
+
+static int
+balance_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
+{
+ if (rq->nr_running)
+ return 1;
+
+ return newidle_balance(rq, rf) != 0;
+}
#endif /* CONFIG_SMP */
static unsigned long wakeup_gran(struct sched_entity *se)
@@ -6746,7 +6755,7 @@ pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf
int new_tasks;
again:
- if (!cfs_rq->nr_running)
+ if (!sched_fair_runnable(rq))
goto idle;
#ifdef CONFIG_FAIR_GROUP_SCHED
@@ -6884,7 +6893,7 @@ idle:
/*
* Account for a descheduled task:
*/
-static void put_prev_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
+static void put_prev_task_fair(struct rq *rq, struct task_struct *prev)
{
struct sched_entity *se = &prev->se;
struct cfs_rq *cfs_rq;
@@ -7539,6 +7548,19 @@ static void update_blocked_averages(int cpu)
update_rq_clock(rq);
/*
+ * update_cfs_rq_load_avg() can call cpufreq_update_util(). Make sure
+ * that RT, DL and IRQ signals have been updated before updating CFS.
+ */
+ curr_class = rq->curr->sched_class;
+ update_rt_rq_load_avg(rq_clock_pelt(rq), rq, curr_class == &rt_sched_class);
+ update_dl_rq_load_avg(rq_clock_pelt(rq), rq, curr_class == &dl_sched_class);
+ update_irq_load_avg(rq, 0);
+
+ /* Don't need periodic decay once load/util_avg are null */
+ if (others_have_blocked(rq))
+ done = false;
+
+ /*
* Iterates the task_group tree in a bottom up fashion, see
* list_add_leaf_cfs_rq() for details.
*/
@@ -7565,14 +7587,6 @@ static void update_blocked_averages(int cpu)
done = false;
}
- curr_class = rq->curr->sched_class;
- update_rt_rq_load_avg(rq_clock_pelt(rq), rq, curr_class == &rt_sched_class);
- update_dl_rq_load_avg(rq_clock_pelt(rq), rq, curr_class == &dl_sched_class);
- update_irq_load_avg(rq, 0);
- /* Don't need periodic decay once load/util_avg are null */
- if (others_have_blocked(rq))
- done = false;
-
update_blocked_load_status(rq, !done);
rq_unlock_irqrestore(rq, &rf);
}
@@ -7633,12 +7647,18 @@ static inline void update_blocked_averages(int cpu)
rq_lock_irqsave(rq, &rf);
update_rq_clock(rq);
- update_cfs_rq_load_avg(cfs_rq_clock_pelt(cfs_rq), cfs_rq);
+ /*
+ * update_cfs_rq_load_avg() can call cpufreq_update_util(). Make sure
+ * that RT, DL and IRQ signals have been updated before updating CFS.
+ */
curr_class = rq->curr->sched_class;
update_rt_rq_load_avg(rq_clock_pelt(rq), rq, curr_class == &rt_sched_class);
update_dl_rq_load_avg(rq_clock_pelt(rq), rq, curr_class == &dl_sched_class);
update_irq_load_avg(rq, 0);
+
+ update_cfs_rq_load_avg(cfs_rq_clock_pelt(cfs_rq), cfs_rq);
+
update_blocked_load_status(rq, cfs_rq_has_blocked(cfs_rq) || others_have_blocked(rq));
rq_unlock_irqrestore(rq, &rf);
}
@@ -10414,11 +10434,11 @@ const struct sched_class fair_sched_class = {
.check_preempt_curr = check_preempt_wakeup,
.pick_next_task = pick_next_task_fair,
-
.put_prev_task = put_prev_task_fair,
.set_next_task = set_next_task_fair,
#ifdef CONFIG_SMP
+ .balance = balance_fair,
.select_task_rq = select_task_rq_fair,
.migrate_task_rq = migrate_task_rq_fair,
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index 8dad5aa600ea..f65ef1e2f204 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -365,6 +365,12 @@ select_task_rq_idle(struct task_struct *p, int cpu, int sd_flag, int flags)
{
return task_cpu(p); /* IDLE tasks as never migrated */
}
+
+static int
+balance_idle(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
+{
+ return WARN_ON_ONCE(1);
+}
#endif
/*
@@ -375,7 +381,7 @@ static void check_preempt_curr_idle(struct rq *rq, struct task_struct *p, int fl
resched_curr(rq);
}
-static void put_prev_task_idle(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
+static void put_prev_task_idle(struct rq *rq, struct task_struct *prev)
{
}
@@ -460,6 +466,7 @@ const struct sched_class idle_sched_class = {
.set_next_task = set_next_task_idle,
#ifdef CONFIG_SMP
+ .balance = balance_idle,
.select_task_rq = select_task_rq_idle,
.set_cpus_allowed = set_cpus_allowed_common,
#endif
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index ebaa4e619684..9b8adc01be3d 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -1469,6 +1469,22 @@ static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p)
resched_curr(rq);
}
+static int balance_rt(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
+{
+ if (!on_rt_rq(&p->rt) && need_pull_rt_task(rq, p)) {
+ /*
+ * This is OK, because current is on_cpu, which avoids it being
+ * picked for load-balance and preemption/IRQs are still
+ * disabled avoiding further scheduler activity on it and we've
+ * not yet started the picking loop.
+ */
+ rq_unpin_lock(rq, rf);
+ pull_rt_task(rq);
+ rq_repin_lock(rq, rf);
+ }
+
+ return sched_stop_runnable(rq) || sched_dl_runnable(rq) || sched_rt_runnable(rq);
+}
#endif /* CONFIG_SMP */
/*
@@ -1552,21 +1568,18 @@ static struct task_struct *
pick_next_task_rt(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
{
struct task_struct *p;
- struct rt_rq *rt_rq = &rq->rt;
WARN_ON_ONCE(prev || rf);
- if (!rt_rq->rt_queued)
+ if (!sched_rt_runnable(rq))
return NULL;
p = _pick_next_task_rt(rq);
-
set_next_task_rt(rq, p);
-
return p;
}
-static void put_prev_task_rt(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
+static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
{
update_curr_rt(rq);
@@ -1578,18 +1591,6 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p, struct rq_fla
*/
if (on_rt_rq(&p->rt) && p->nr_cpus_allowed > 1)
enqueue_pushable_task(rq, p);
-
- if (rf && !on_rt_rq(&p->rt) && need_pull_rt_task(rq, p)) {
- /*
- * This is OK, because current is on_cpu, which avoids it being
- * picked for load-balance and preemption/IRQs are still
- * disabled avoiding further scheduler activity on it and we've
- * not yet started the picking loop.
- */
- rq_unpin_lock(rq, rf);
- pull_rt_task(rq);
- rq_repin_lock(rq, rf);
- }
}
#ifdef CONFIG_SMP
@@ -2366,8 +2367,8 @@ const struct sched_class rt_sched_class = {
.set_next_task = set_next_task_rt,
#ifdef CONFIG_SMP
+ .balance = balance_rt,
.select_task_rq = select_task_rq_rt,
-
.set_cpus_allowed = set_cpus_allowed_common,
.rq_online = rq_online_rt,
.rq_offline = rq_offline_rt,
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 0db2c1b3361e..c8870c5bd7df 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1727,10 +1727,11 @@ struct sched_class {
struct task_struct * (*pick_next_task)(struct rq *rq,
struct task_struct *prev,
struct rq_flags *rf);
- void (*put_prev_task)(struct rq *rq, struct task_struct *p, struct rq_flags *rf);
+ void (*put_prev_task)(struct rq *rq, struct task_struct *p);
void (*set_next_task)(struct rq *rq, struct task_struct *p);
#ifdef CONFIG_SMP
+ int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
@@ -1773,7 +1774,7 @@ struct sched_class {
static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
{
WARN_ON_ONCE(rq->curr != prev);
- prev->sched_class->put_prev_task(rq, prev, NULL);
+ prev->sched_class->put_prev_task(rq, prev);
}
static inline void set_next_task(struct rq *rq, struct task_struct *next)
@@ -1787,8 +1788,12 @@ static inline void set_next_task(struct rq *rq, struct task_struct *next)
#else
#define sched_class_highest (&dl_sched_class)
#endif
+
+#define for_class_range(class, _from, _to) \
+ for (class = (_from); class != (_to); class = class->next)
+
#define for_each_class(class) \
- for (class = sched_class_highest; class; class = class->next)
+ for_class_range(class, sched_class_highest, NULL)
extern const struct sched_class stop_sched_class;
extern const struct sched_class dl_sched_class;
@@ -1796,6 +1801,25 @@ extern const struct sched_class rt_sched_class;
extern const struct sched_class fair_sched_class;
extern const struct sched_class idle_sched_class;
+static inline bool sched_stop_runnable(struct rq *rq)
+{
+ return rq->stop && task_on_rq_queued(rq->stop);
+}
+
+static inline bool sched_dl_runnable(struct rq *rq)
+{
+ return rq->dl.dl_nr_running > 0;
+}
+
+static inline bool sched_rt_runnable(struct rq *rq)
+{
+ return rq->rt.rt_queued > 0;
+}
+
+static inline bool sched_fair_runnable(struct rq *rq)
+{
+ return rq->cfs.nr_running > 0;
+}
#ifdef CONFIG_SMP
diff --git a/kernel/sched/stop_task.c b/kernel/sched/stop_task.c
index 7e1cee4e65b2..c0640739e05e 100644
--- a/kernel/sched/stop_task.c
+++ b/kernel/sched/stop_task.c
@@ -15,6 +15,12 @@ select_task_rq_stop(struct task_struct *p, int cpu, int sd_flag, int flags)
{
return task_cpu(p); /* stop tasks as never migrate */
}
+
+static int
+balance_stop(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
+{
+ return sched_stop_runnable(rq);
+}
#endif /* CONFIG_SMP */
static void
@@ -31,16 +37,13 @@ static void set_next_task_stop(struct rq *rq, struct task_struct *stop)
static struct task_struct *
pick_next_task_stop(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
{
- struct task_struct *stop = rq->stop;
-
WARN_ON_ONCE(prev || rf);
- if (!stop || !task_on_rq_queued(stop))
+ if (!sched_stop_runnable(rq))
return NULL;
- set_next_task_stop(rq, stop);
-
- return stop;
+ set_next_task_stop(rq, rq->stop);
+ return rq->stop;
}
static void
@@ -60,7 +63,7 @@ static void yield_task_stop(struct rq *rq)
BUG(); /* the stop task should never yield, its pointless. */
}
-static void put_prev_task_stop(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
+static void put_prev_task_stop(struct rq *rq, struct task_struct *prev)
{
struct task_struct *curr = rq->curr;
u64 delta_exec;
@@ -129,6 +132,7 @@ const struct sched_class stop_sched_class = {
.set_next_task = set_next_task_stop,
#ifdef CONFIG_SMP
+ .balance = balance_stop,
.select_task_rq = select_task_rq_stop,
.set_cpus_allowed = set_cpus_allowed_common,
#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-24 00:40:40 +0000