summaryrefslogtreecommitdiff
path: root/kernel/sched
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/sched')
-rw-r--r--kernel/sched/core.c112
-rw-r--r--kernel/sched/cpupri.c10
-rw-r--r--kernel/sched/fair.c77
-rw-r--r--kernel/sched/rt.c14
-rw-r--r--kernel/sched/sched.h9
-rw-r--r--kernel/sched/stop_task.c22
6 files changed, 128 insertions, 116 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index d325c4b2dcbb..649c9f876cb1 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);
@@ -4340,9 +4346,7 @@ recheck:
*/
if (unlikely(policy == p->policy && (!rt_policy(policy) ||
param->sched_priority == p->rt_priority))) {
-
- __task_rq_unlock(rq);
- raw_spin_unlock_irqrestore(&p->pi_lock, flags);
+ task_rq_unlock(rq, p, &flags);
return 0;
}
@@ -5300,27 +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);
}
/*
@@ -5348,9 +5342,6 @@ static void migrate_tasks(unsigned int dead_cpu)
*/
rq->stop = NULL;
- /* Ensure any throttled groups are reachable by pick_next_task */
- unthrottle_offline_cfs_rqs(rq);
-
for ( ; ; ) {
/*
* There's this thread running, bail when that's the only
@@ -5614,8 +5605,7 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
BUG_ON(rq->nr_running != 1); /* the migration thread */
raw_spin_unlock_irqrestore(&rq->lock, flags);
- migrate_nr_uninterruptible(rq);
- calc_global_load_remove(rq);
+ calc_load_migrate(rq);
break;
#endif
}
@@ -6024,11 +6014,6 @@ static void destroy_sched_domains(struct sched_domain *sd, int cpu)
* SD_SHARE_PKG_RESOURCE set (Last Level Cache Domain) for this
* allows us to avoid some pointer chasing select_idle_sibling().
*
- * Iterate domains and sched_groups downward, assigning CPUs to be
- * select_idle_sibling() hw buddy. Cross-wiring hw makes bouncing
- * due to random perturbation self canceling, ie sw buddies pull
- * their counterpart to their CPU's hw counterpart.
- *
* Also keep a unique ID per domain (we use the first cpu number in
* the cpumask of the domain), this allows us to quickly tell if
* two cpus are in the same cache domain, see cpus_share_cache().
@@ -6042,40 +6027,8 @@ static void update_top_cache_domain(int cpu)
int id = cpu;
sd = highest_flag_domain(cpu, SD_SHARE_PKG_RESOURCES);
- if (sd) {
- struct sched_domain *tmp = sd;
- struct sched_group *sg, *prev;
- bool right;
-
- /*
- * Traverse to first CPU in group, and count hops
- * to cpu from there, switching direction on each
- * hop, never ever pointing the last CPU rightward.
- */
- do {
- id = cpumask_first(sched_domain_span(tmp));
- prev = sg = tmp->groups;
- right = 1;
-
- while (cpumask_first(sched_group_cpus(sg)) != id)
- sg = sg->next;
-
- while (!cpumask_test_cpu(cpu, sched_group_cpus(sg))) {
- prev = sg;
- sg = sg->next;
- right = !right;
- }
-
- /* A CPU went down, never point back to domain start. */
- if (right && cpumask_first(sched_group_cpus(sg->next)) == id)
- right = false;
-
- sg = right ? sg->next : prev;
- tmp->idle_buddy = cpumask_first(sched_group_cpus(sg));
- } while ((tmp = tmp->child));
-
+ if (sd)
id = cpumask_first(sched_domain_span(sd));
- }
rcu_assign_pointer(per_cpu(sd_llc, cpu), sd);
per_cpu(sd_llc_id, cpu) = id;
@@ -7248,6 +7201,7 @@ 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);
diff --git a/kernel/sched/cpupri.c b/kernel/sched/cpupri.c
index d72586fdf660..23aa789c53ee 100644
--- a/kernel/sched/cpupri.c
+++ b/kernel/sched/cpupri.c
@@ -65,8 +65,8 @@ static int convert_prio(int prio)
int cpupri_find(struct cpupri *cp, struct task_struct *p,
struct cpumask *lowest_mask)
{
- int idx = 0;
- int task_pri = convert_prio(p->prio);
+ int idx = 0;
+ int task_pri = convert_prio(p->prio);
if (task_pri >= MAX_RT_PRIO)
return 0;
@@ -137,9 +137,9 @@ int cpupri_find(struct cpupri *cp, struct task_struct *p,
*/
void cpupri_set(struct cpupri *cp, int cpu, int newpri)
{
- int *currpri = &cp->cpu_to_pri[cpu];
- int oldpri = *currpri;
- int do_mb = 0;
+ int *currpri = &cp->cpu_to_pri[cpu];
+ int oldpri = *currpri;
+ int do_mb = 0;
newpri = convert_prio(newpri);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 22321db64952..96e2b18b6283 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2052,7 +2052,7 @@ static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
hrtimer_cancel(&cfs_b->slack_timer);
}
-void unthrottle_offline_cfs_rqs(struct rq *rq)
+static void unthrottle_offline_cfs_rqs(struct rq *rq)
{
struct cfs_rq *cfs_rq;
@@ -2106,7 +2106,7 @@ static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg)
return NULL;
}
static inline void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {}
-void unthrottle_offline_cfs_rqs(struct rq *rq) {}
+static inline void unthrottle_offline_cfs_rqs(struct rq *rq) {}
#endif /* CONFIG_CFS_BANDWIDTH */
@@ -2637,6 +2637,8 @@ static int select_idle_sibling(struct task_struct *p, int target)
int cpu = smp_processor_id();
int prev_cpu = task_cpu(p);
struct sched_domain *sd;
+ struct sched_group *sg;
+ int i;
/*
* If the task is going to be woken-up on this cpu and if it is
@@ -2653,17 +2655,29 @@ static int select_idle_sibling(struct task_struct *p, int target)
return prev_cpu;
/*
- * Otherwise, check assigned siblings to find an elegible idle cpu.
+ * Otherwise, iterate the domains and find an elegible idle cpu.
*/
sd = rcu_dereference(per_cpu(sd_llc, target));
-
for_each_lower_domain(sd) {
- if (!cpumask_test_cpu(sd->idle_buddy, tsk_cpus_allowed(p)))
- continue;
- if (idle_cpu(sd->idle_buddy))
- return sd->idle_buddy;
- }
+ sg = sd->groups;
+ do {
+ if (!cpumask_intersects(sched_group_cpus(sg),
+ tsk_cpus_allowed(p)))
+ goto next;
+ for_each_cpu(i, sched_group_cpus(sg)) {
+ if (!idle_cpu(i))
+ goto next;
+ }
+
+ target = cpumask_first_and(sched_group_cpus(sg),
+ tsk_cpus_allowed(p));
+ goto done;
+next:
+ sg = sg->next;
+ } while (sg != sd->groups);
+ }
+done:
return target;
}
@@ -3069,6 +3083,9 @@ struct lb_env {
int new_dst_cpu;
enum cpu_idle_type idle;
long imbalance;
+ /* The set of CPUs under consideration for load-balancing */
+ struct cpumask *cpus;
+
unsigned int flags;
unsigned int loop;
@@ -3384,6 +3401,14 @@ static int tg_load_down(struct task_group *tg, void *data)
static void update_h_load(long cpu)
{
+ struct rq *rq = cpu_rq(cpu);
+ unsigned long now = jiffies;
+
+ if (rq->h_load_throttle == now)
+ return;
+
+ rq->h_load_throttle = now;
+
rcu_read_lock();
walk_tg_tree(tg_load_down, tg_nop, (void *)cpu);
rcu_read_unlock();
@@ -3647,14 +3672,12 @@ fix_small_capacity(struct sched_domain *sd, struct sched_group *group)
* @group: sched_group whose statistics are to be updated.
* @load_idx: Load index of sched_domain of this_cpu for load calc.
* @local_group: Does group contain this_cpu.
- * @cpus: Set of cpus considered for load balancing.
* @balance: Should we balance.
* @sgs: variable to hold the statistics for this group.
*/
static inline void update_sg_lb_stats(struct lb_env *env,
struct sched_group *group, int load_idx,
- int local_group, const struct cpumask *cpus,
- int *balance, struct sg_lb_stats *sgs)
+ int local_group, int *balance, struct sg_lb_stats *sgs)
{
unsigned long nr_running, max_nr_running, min_nr_running;
unsigned long load, max_cpu_load, min_cpu_load;
@@ -3671,7 +3694,7 @@ static inline void update_sg_lb_stats(struct lb_env *env,
max_nr_running = 0;
min_nr_running = ~0UL;
- for_each_cpu_and(i, sched_group_cpus(group), cpus) {
+ for_each_cpu_and(i, sched_group_cpus(group), env->cpus) {
struct rq *rq = cpu_rq(i);
nr_running = rq->nr_running;
@@ -3795,13 +3818,11 @@ static bool update_sd_pick_busiest(struct lb_env *env,
/**
* update_sd_lb_stats - Update sched_domain's statistics for load balancing.
* @env: The load balancing environment.
- * @cpus: Set of cpus considered for load balancing.
* @balance: Should we balance.
* @sds: variable to hold the statistics for this sched_domain.
*/
static inline void update_sd_lb_stats(struct lb_env *env,
- const struct cpumask *cpus,
- int *balance, struct sd_lb_stats *sds)
+ int *balance, struct sd_lb_stats *sds)
{
struct sched_domain *child = env->sd->child;
struct sched_group *sg = env->sd->groups;
@@ -3818,8 +3839,7 @@ static inline void update_sd_lb_stats(struct lb_env *env,
local_group = cpumask_test_cpu(env->dst_cpu, sched_group_cpus(sg));
memset(&sgs, 0, sizeof(sgs));
- update_sg_lb_stats(env, sg, load_idx, local_group,
- cpus, balance, &sgs);
+ update_sg_lb_stats(env, sg, load_idx, local_group, balance, &sgs);
if (local_group && !(*balance))
return;
@@ -4055,7 +4075,6 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
* to restore balance.
*
* @env: The load balancing environment.
- * @cpus: The set of CPUs under consideration for load-balancing.
* @balance: Pointer to a variable indicating if this_cpu
* is the appropriate cpu to perform load balancing at this_level.
*
@@ -4065,7 +4084,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
* put to idle by rebalancing its tasks onto our group.
*/
static struct sched_group *
-find_busiest_group(struct lb_env *env, const struct cpumask *cpus, int *balance)
+find_busiest_group(struct lb_env *env, int *balance)
{
struct sd_lb_stats sds;
@@ -4075,7 +4094,7 @@ find_busiest_group(struct lb_env *env, const struct cpumask *cpus, int *balance)
* Compute the various statistics relavent for load balancing at
* this level.
*/
- update_sd_lb_stats(env, cpus, balance, &sds);
+ update_sd_lb_stats(env, balance, &sds);
/*
* this_cpu is not the appropriate cpu to perform load balancing at
@@ -4155,8 +4174,7 @@ ret:
* find_busiest_queue - find the busiest runqueue among the cpus in group.
*/
static struct rq *find_busiest_queue(struct lb_env *env,
- struct sched_group *group,
- const struct cpumask *cpus)
+ struct sched_group *group)
{
struct rq *busiest = NULL, *rq;
unsigned long max_load = 0;
@@ -4171,7 +4189,7 @@ static struct rq *find_busiest_queue(struct lb_env *env,
if (!capacity)
capacity = fix_small_capacity(env->sd, group);
- if (!cpumask_test_cpu(i, cpus))
+ if (!cpumask_test_cpu(i, env->cpus))
continue;
rq = cpu_rq(i);
@@ -4252,6 +4270,7 @@ static int load_balance(int this_cpu, struct rq *this_rq,
.dst_grpmask = sched_group_cpus(sd->groups),
.idle = idle,
.loop_break = sched_nr_migrate_break,
+ .cpus = cpus,
};
cpumask_copy(cpus, cpu_active_mask);
@@ -4260,7 +4279,7 @@ static int load_balance(int this_cpu, struct rq *this_rq,
schedstat_inc(sd, lb_count[idle]);
redo:
- group = find_busiest_group(&env, cpus, balance);
+ group = find_busiest_group(&env, balance);
if (*balance == 0)
goto out_balanced;
@@ -4270,7 +4289,7 @@ redo:
goto out_balanced;
}
- busiest = find_busiest_queue(&env, group, cpus);
+ busiest = find_busiest_queue(&env, group);
if (!busiest) {
schedstat_inc(sd, lb_nobusyq[idle]);
goto out_balanced;
@@ -4294,11 +4313,10 @@ redo:
env.src_rq = busiest;
env.loop_max = min(sysctl_sched_nr_migrate, busiest->nr_running);
+ update_h_load(env.src_cpu);
more_balance:
local_irq_save(flags);
double_rq_lock(this_rq, busiest);
- if (!env.loop)
- update_h_load(env.src_cpu);
/*
* cur_ld_moved - load moved in current iteration
@@ -4950,6 +4968,9 @@ static void rq_online_fair(struct rq *rq)
static void rq_offline_fair(struct rq *rq)
{
update_sysctl();
+
+ /* Ensure any throttled groups are reachable by pick_next_task */
+ unthrottle_offline_cfs_rqs(rq);
}
#endif /* CONFIG_SMP */
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 573e1ca01102..e0b7ba9c040f 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -691,6 +691,7 @@ balanced:
* runtime - in which case borrowing doesn't make sense.
*/
rt_rq->rt_runtime = RUNTIME_INF;
+ rt_rq->rt_throttled = 0;
raw_spin_unlock(&rt_rq->rt_runtime_lock);
raw_spin_unlock(&rt_b->rt_runtime_lock);
}
@@ -788,6 +789,19 @@ static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun)
const struct cpumask *span;
span = sched_rt_period_mask();
+#ifdef CONFIG_RT_GROUP_SCHED
+ /*
+ * FIXME: isolated CPUs should really leave the root task group,
+ * whether they are isolcpus or were isolated via cpusets, lest
+ * the timer run on a CPU which does not service all runqueues,
+ * potentially leaving other CPUs indefinitely throttled. If
+ * isolation is really required, the user will turn the throttle
+ * off to kill the perturbations it causes anyway. Meanwhile,
+ * this maintains functionality for boot and/or troubleshooting.
+ */
+ if (rt_b == &root_task_group.rt_bandwidth)
+ span = cpu_online_mask;
+#endif
for_each_cpu(i, span) {
int enqueue = 0;
struct rt_rq *rt_rq = sched_rt_period_rt_rq(rt_b, i);
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index c35a1a7dd4d6..0848fa36c383 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -80,7 +80,7 @@ extern struct mutex sched_domains_mutex;
struct cfs_rq;
struct rt_rq;
-static LIST_HEAD(task_groups);
+extern struct list_head task_groups;
struct cfs_bandwidth {
#ifdef CONFIG_CFS_BANDWIDTH
@@ -374,7 +374,11 @@ struct rq {
#ifdef CONFIG_FAIR_GROUP_SCHED
/* list of leaf cfs_rq on this cpu: */
struct list_head leaf_cfs_rq_list;
-#endif
+#ifdef CONFIG_SMP
+ unsigned long h_load_throttle;
+#endif /* CONFIG_SMP */
+#endif /* CONFIG_FAIR_GROUP_SCHED */
+
#ifdef CONFIG_RT_GROUP_SCHED
struct list_head leaf_rt_rq_list;
#endif
@@ -1140,7 +1144,6 @@ extern void print_rt_stats(struct seq_file *m, int cpu);
extern void init_cfs_rq(struct cfs_rq *cfs_rq);
extern void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq);
-extern void unthrottle_offline_cfs_rqs(struct rq *rq);
extern void account_cfs_bandwidth_used(int enabled, int was_enabled);
diff --git a/kernel/sched/stop_task.c b/kernel/sched/stop_task.c
index 7b386e86fd23..da5eb5bed84a 100644
--- a/kernel/sched/stop_task.c
+++ b/kernel/sched/stop_task.c
@@ -27,8 +27,10 @@ static struct task_struct *pick_next_task_stop(struct rq *rq)
{
struct task_struct *stop = rq->stop;
- if (stop && stop->on_rq)
+ if (stop && stop->on_rq) {
+ stop->se.exec_start = rq->clock_task;
return stop;
+ }
return NULL;
}
@@ -52,6 +54,21 @@ static void yield_task_stop(struct rq *rq)
static void put_prev_task_stop(struct rq *rq, struct task_struct *prev)
{
+ struct task_struct *curr = rq->curr;
+ u64 delta_exec;
+
+ delta_exec = rq->clock_task - curr->se.exec_start;
+ if (unlikely((s64)delta_exec < 0))
+ delta_exec = 0;
+
+ schedstat_set(curr->se.statistics.exec_max,
+ max(curr->se.statistics.exec_max, delta_exec));
+
+ curr->se.sum_exec_runtime += delta_exec;
+ account_group_exec_runtime(curr, delta_exec);
+
+ curr->se.exec_start = rq->clock_task;
+ cpuacct_charge(curr, delta_exec);
}
static void task_tick_stop(struct rq *rq, struct task_struct *curr, int queued)
@@ -60,6 +77,9 @@ static void task_tick_stop(struct rq *rq, struct task_struct *curr, int queued)
static void set_curr_task_stop(struct rq *rq)
{
+ struct task_struct *stop = rq->stop;
+
+ stop->se.exec_start = rq->clock_task;
}
static void switched_to_stop(struct rq *rq, struct task_struct *p)
generated by cgit v1.2.3 (git 2.39.1) at 2024-10-08 12:33:20 +0000