sched: Make struct sched_statistics independent of fair sched class
authorYafang Shao <laoar.shao@gmail.com>
Sun, 5 Sep 2021 14:35:41 +0000 (14:35 +0000)
committerPeter Zijlstra <peterz@infradead.org>
Tue, 5 Oct 2021 13:51:45 +0000 (15:51 +0200)
If we want to use the schedstats facility to trace other sched classes, we
should make it independent of fair sched class. The struct sched_statistics
is the schedular statistics of a task_struct or a task_group. So we can
move it into struct task_struct and struct task_group to achieve the goal.

After the patch, schestats are orgnized as follows,

    struct task_struct {
       ...
       struct sched_entity se;
       struct sched_rt_entity rt;
       struct sched_dl_entity dl;
       ...
       struct sched_statistics stats;
       ...
   };

Regarding the task group, schedstats is only supported for fair group
sched, and a new struct sched_entity_stats is introduced, suggested by
Peter -

    struct sched_entity_stats {
        struct sched_entity     se;
        struct sched_statistics stats;
    } __no_randomize_layout;

Then with the se in a task_group, we can easily get the stats.

The sched_statistics members may be frequently modified when schedstats is
enabled, in order to avoid impacting on random data which may in the same
cacheline with them, the struct sched_statistics is defined as cacheline
aligned.

As this patch changes the core struct of scheduler, so I verified the
performance it may impact on the scheduler with 'perf bench sched
pipe', suggested by Mel. Below is the result, in which all the values
are in usecs/op.
                                  Before               After
      kernel.sched_schedstats=0  5.2~5.4               5.2~5.4
      kernel.sched_schedstats=1  5.3~5.5               5.3~5.5
[These data is a little difference with the earlier version, that is
 because my old test machine is destroyed so I have to use a new
 different test machine.]

Almost no impact on the sched performance.

No functional change.

[lkp@intel.com: reported build failure in earlier version]

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Link: https://lore.kernel.org/r/20210905143547.4668-3-laoar.shao@gmail.com
include/linux/sched.h
kernel/sched/core.c
kernel/sched/deadline.c
kernel/sched/debug.c
kernel/sched/fair.c
kernel/sched/rt.c
kernel/sched/stats.h
kernel/sched/stop_task.c

index c1a927d..2bc4c72 100644 (file)
@@ -522,7 +522,7 @@ struct sched_statistics {
        u64                             nr_wakeups_passive;
        u64                             nr_wakeups_idle;
 #endif
-};
+} ____cacheline_aligned;
 
 struct sched_entity {
        /* For load-balancing: */
@@ -538,8 +538,6 @@ struct sched_entity {
 
        u64                             nr_migrations;
 
-       struct sched_statistics         statistics;
-
 #ifdef CONFIG_FAIR_GROUP_SCHED
        int                             depth;
        struct sched_entity             *parent;
@@ -803,6 +801,8 @@ struct task_struct {
        struct uclamp_se                uclamp[UCLAMP_CNT];
 #endif
 
+       struct sched_statistics         stats;
+
 #ifdef CONFIG_PREEMPT_NOTIFIERS
        /* List of struct preempt_notifier: */
        struct hlist_head               preempt_notifiers;
index ccb604a..a1741e0 100644 (file)
@@ -3489,11 +3489,11 @@ ttwu_stat(struct task_struct *p, int cpu, int wake_flags)
 #ifdef CONFIG_SMP
        if (cpu == rq->cpu) {
                __schedstat_inc(rq->ttwu_local);
-               __schedstat_inc(p->se.statistics.nr_wakeups_local);
+               __schedstat_inc(p->stats.nr_wakeups_local);
        } else {
                struct sched_domain *sd;
 
-               __schedstat_inc(p->se.statistics.nr_wakeups_remote);
+               __schedstat_inc(p->stats.nr_wakeups_remote);
                rcu_read_lock();
                for_each_domain(rq->cpu, sd) {
                        if (cpumask_test_cpu(cpu, sched_domain_span(sd))) {
@@ -3505,14 +3505,14 @@ ttwu_stat(struct task_struct *p, int cpu, int wake_flags)
        }
 
        if (wake_flags & WF_MIGRATED)
-               __schedstat_inc(p->se.statistics.nr_wakeups_migrate);
+               __schedstat_inc(p->stats.nr_wakeups_migrate);
 #endif /* CONFIG_SMP */
 
        __schedstat_inc(rq->ttwu_count);
-       __schedstat_inc(p->se.statistics.nr_wakeups);
+       __schedstat_inc(p->stats.nr_wakeups);
 
        if (wake_flags & WF_SYNC)
-               __schedstat_inc(p->se.statistics.nr_wakeups_sync);
+               __schedstat_inc(p->stats.nr_wakeups_sync);
 }
 
 /*
@@ -4196,7 +4196,7 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p)
 
 #ifdef CONFIG_SCHEDSTATS
        /* Even if schedstat is disabled, there should not be garbage */
-       memset(&p->se.statistics, 0, sizeof(p->se.statistics));
+       memset(&p->stats, 0, sizeof(p->stats));
 #endif
 
        RB_CLEAR_NODE(&p->dl.rb_node);
@@ -9553,9 +9553,9 @@ void normalize_rt_tasks(void)
                        continue;
 
                p->se.exec_start = 0;
-               schedstat_set(p->se.statistics.wait_start,  0);
-               schedstat_set(p->se.statistics.sleep_start, 0);
-               schedstat_set(p->se.statistics.block_start, 0);
+               schedstat_set(p->stats.wait_start,  0);
+               schedstat_set(p->stats.sleep_start, 0);
+               schedstat_set(p->stats.block_start, 0);
 
                if (!dl_task(p) && !rt_task(p)) {
                        /*
@@ -10397,11 +10397,14 @@ static int cpu_cfs_stat_show(struct seq_file *sf, void *v)
        seq_printf(sf, "throttled_time %llu\n", cfs_b->throttled_time);
 
        if (schedstat_enabled() && tg != &root_task_group) {
+               struct sched_statistics *stats;
                u64 ws = 0;
                int i;
 
-               for_each_possible_cpu(i)
-                       ws += schedstat_val(tg->se[i]->statistics.wait_sum);
+               for_each_possible_cpu(i) {
+                       stats = __schedstats_from_se(tg->se[i]);
+                       ws += schedstat_val(stats->wait_sum);
+               }
 
                seq_printf(sf, "wait_sum %llu\n", ws);
        }
index e943146..51dd309 100644 (file)
@@ -1265,8 +1265,8 @@ static void update_curr_dl(struct rq *rq)
                return;
        }
 
-       schedstat_set(curr->se.statistics.exec_max,
-                     max(curr->se.statistics.exec_max, delta_exec));
+       schedstat_set(curr->stats.exec_max,
+                     max(curr->stats.exec_max, delta_exec));
 
        curr->se.sum_exec_runtime += delta_exec;
        account_group_exec_runtime(curr, delta_exec);
index 34913a7..76fd38e 100644 (file)
@@ -449,9 +449,11 @@ static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group
        struct sched_entity *se = tg->se[cpu];
 
 #define P(F)           SEQ_printf(m, "  .%-30s: %lld\n",       #F, (long long)F)
-#define P_SCHEDSTAT(F) SEQ_printf(m, "  .%-30s: %lld\n",       #F, (long long)schedstat_val(F))
+#define P_SCHEDSTAT(F) SEQ_printf(m, "  .%-30s: %lld\n",       \
+               #F, (long long)schedstat_val(stats->F))
 #define PN(F)          SEQ_printf(m, "  .%-30s: %lld.%06ld\n", #F, SPLIT_NS((long long)F))
-#define PN_SCHEDSTAT(F)        SEQ_printf(m, "  .%-30s: %lld.%06ld\n", #F, SPLIT_NS((long long)schedstat_val(F)))
+#define PN_SCHEDSTAT(F)        SEQ_printf(m, "  .%-30s: %lld.%06ld\n", \
+               #F, SPLIT_NS((long long)schedstat_val(stats->F)))
 
        if (!se)
                return;
@@ -461,16 +463,18 @@ static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group
        PN(se->sum_exec_runtime);
 
        if (schedstat_enabled()) {
-               PN_SCHEDSTAT(se->statistics.wait_start);
-               PN_SCHEDSTAT(se->statistics.sleep_start);
-               PN_SCHEDSTAT(se->statistics.block_start);
-               PN_SCHEDSTAT(se->statistics.sleep_max);
-               PN_SCHEDSTAT(se->statistics.block_max);
-               PN_SCHEDSTAT(se->statistics.exec_max);
-               PN_SCHEDSTAT(se->statistics.slice_max);
-               PN_SCHEDSTAT(se->statistics.wait_max);
-               PN_SCHEDSTAT(se->statistics.wait_sum);
-               P_SCHEDSTAT(se->statistics.wait_count);
+               struct sched_statistics *stats =  __schedstats_from_se(se);
+
+               PN_SCHEDSTAT(wait_start);
+               PN_SCHEDSTAT(sleep_start);
+               PN_SCHEDSTAT(block_start);
+               PN_SCHEDSTAT(sleep_max);
+               PN_SCHEDSTAT(block_max);
+               PN_SCHEDSTAT(exec_max);
+               PN_SCHEDSTAT(slice_max);
+               PN_SCHEDSTAT(wait_max);
+               PN_SCHEDSTAT(wait_sum);
+               P_SCHEDSTAT(wait_count);
        }
 
        P(se->load.weight);
@@ -537,9 +541,9 @@ print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
                p->prio);
 
        SEQ_printf(m, "%9Ld.%06ld %9Ld.%06ld %9Ld.%06ld",
-               SPLIT_NS(schedstat_val_or_zero(p->se.statistics.wait_sum)),
+               SPLIT_NS(schedstat_val_or_zero(p->stats.wait_sum)),
                SPLIT_NS(p->se.sum_exec_runtime),
-               SPLIT_NS(schedstat_val_or_zero(p->se.statistics.sum_sleep_runtime)));
+               SPLIT_NS(schedstat_val_or_zero(p->stats.sum_sleep_runtime)));
 
 #ifdef CONFIG_NUMA_BALANCING
        SEQ_printf(m, " %d %d", task_node(p), task_numa_group_id(p));
@@ -958,8 +962,8 @@ void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns,
                "---------------------------------------------------------"
                "----------\n");
 
-#define P_SCHEDSTAT(F)  __PS(#F, schedstat_val(p->F))
-#define PN_SCHEDSTAT(F) __PSN(#F, schedstat_val(p->F))
+#define P_SCHEDSTAT(F)  __PS(#F, schedstat_val(p->stats.F))
+#define PN_SCHEDSTAT(F) __PSN(#F, schedstat_val(p->stats.F))
 
        PN(se.exec_start);
        PN(se.vruntime);
@@ -972,33 +976,33 @@ void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns,
        if (schedstat_enabled()) {
                u64 avg_atom, avg_per_cpu;
 
-               PN_SCHEDSTAT(se.statistics.sum_sleep_runtime);
-               PN_SCHEDSTAT(se.statistics.wait_start);
-               PN_SCHEDSTAT(se.statistics.sleep_start);
-               PN_SCHEDSTAT(se.statistics.block_start);
-               PN_SCHEDSTAT(se.statistics.sleep_max);
-               PN_SCHEDSTAT(se.statistics.block_max);
-               PN_SCHEDSTAT(se.statistics.exec_max);
-               PN_SCHEDSTAT(se.statistics.slice_max);
-               PN_SCHEDSTAT(se.statistics.wait_max);
-               PN_SCHEDSTAT(se.statistics.wait_sum);
-               P_SCHEDSTAT(se.statistics.wait_count);
-               PN_SCHEDSTAT(se.statistics.iowait_sum);
-               P_SCHEDSTAT(se.statistics.iowait_count);
-               P_SCHEDSTAT(se.statistics.nr_migrations_cold);
-               P_SCHEDSTAT(se.statistics.nr_failed_migrations_affine);
-               P_SCHEDSTAT(se.statistics.nr_failed_migrations_running);
-               P_SCHEDSTAT(se.statistics.nr_failed_migrations_hot);
-               P_SCHEDSTAT(se.statistics.nr_forced_migrations);
-               P_SCHEDSTAT(se.statistics.nr_wakeups);
-               P_SCHEDSTAT(se.statistics.nr_wakeups_sync);
-               P_SCHEDSTAT(se.statistics.nr_wakeups_migrate);
-               P_SCHEDSTAT(se.statistics.nr_wakeups_local);
-               P_SCHEDSTAT(se.statistics.nr_wakeups_remote);
-               P_SCHEDSTAT(se.statistics.nr_wakeups_affine);
-               P_SCHEDSTAT(se.statistics.nr_wakeups_affine_attempts);
-               P_SCHEDSTAT(se.statistics.nr_wakeups_passive);
-               P_SCHEDSTAT(se.statistics.nr_wakeups_idle);
+               PN_SCHEDSTAT(sum_sleep_runtime);
+               PN_SCHEDSTAT(wait_start);
+               PN_SCHEDSTAT(sleep_start);
+               PN_SCHEDSTAT(block_start);
+               PN_SCHEDSTAT(sleep_max);
+               PN_SCHEDSTAT(block_max);
+               PN_SCHEDSTAT(exec_max);
+               PN_SCHEDSTAT(slice_max);
+               PN_SCHEDSTAT(wait_max);
+               PN_SCHEDSTAT(wait_sum);
+               P_SCHEDSTAT(wait_count);
+               PN_SCHEDSTAT(iowait_sum);
+               P_SCHEDSTAT(iowait_count);
+               P_SCHEDSTAT(nr_migrations_cold);
+               P_SCHEDSTAT(nr_failed_migrations_affine);
+               P_SCHEDSTAT(nr_failed_migrations_running);
+               P_SCHEDSTAT(nr_failed_migrations_hot);
+               P_SCHEDSTAT(nr_forced_migrations);
+               P_SCHEDSTAT(nr_wakeups);
+               P_SCHEDSTAT(nr_wakeups_sync);
+               P_SCHEDSTAT(nr_wakeups_migrate);
+               P_SCHEDSTAT(nr_wakeups_local);
+               P_SCHEDSTAT(nr_wakeups_remote);
+               P_SCHEDSTAT(nr_wakeups_affine);
+               P_SCHEDSTAT(nr_wakeups_affine_attempts);
+               P_SCHEDSTAT(nr_wakeups_passive);
+               P_SCHEDSTAT(nr_wakeups_idle);
 
                avg_atom = p->se.sum_exec_runtime;
                if (nr_switches)
@@ -1064,7 +1068,7 @@ void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns,
 void proc_sched_set_task(struct task_struct *p)
 {
 #ifdef CONFIG_SCHEDSTATS
-       memset(&p->se.statistics, 0, sizeof(p->se.statistics));
+       memset(&p->stats, 0, sizeof(p->stats));
 #endif
 }
 
index 61d3e3b..97c6ecb 100644 (file)
@@ -856,8 +856,13 @@ static void update_curr(struct cfs_rq *cfs_rq)
 
        curr->exec_start = now;
 
-       schedstat_set(curr->statistics.exec_max,
-                     max(delta_exec, curr->statistics.exec_max));
+       if (schedstat_enabled()) {
+               struct sched_statistics *stats;
+
+               stats = __schedstats_from_se(curr);
+               __schedstat_set(stats->exec_max,
+                               max(delta_exec, stats->exec_max));
+       }
 
        curr->sum_exec_runtime += delta_exec;
        schedstat_add(cfs_rq->exec_clock, delta_exec);
@@ -885,39 +890,45 @@ static inline void
 update_stats_wait_start(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
        u64 wait_start, prev_wait_start;
+       struct sched_statistics *stats;
 
        if (!schedstat_enabled())
                return;
 
+       stats = __schedstats_from_se(se);
+
        wait_start = rq_clock(rq_of(cfs_rq));
-       prev_wait_start = schedstat_val(se->statistics.wait_start);
+       prev_wait_start = schedstat_val(stats->wait_start);
 
        if (entity_is_task(se) && task_on_rq_migrating(task_of(se)) &&
            likely(wait_start > prev_wait_start))
                wait_start -= prev_wait_start;
 
-       __schedstat_set(se->statistics.wait_start, wait_start);
+       __schedstat_set(stats->wait_start, wait_start);
 }
 
 static inline void
 update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
-       struct task_struct *p;
+       struct sched_statistics *stats;
+       struct task_struct *p = NULL;
        u64 delta;
 
        if (!schedstat_enabled())
                return;
 
+       stats = __schedstats_from_se(se);
+
        /*
         * When the sched_schedstat changes from 0 to 1, some sched se
         * maybe already in the runqueue, the se->statistics.wait_start
         * will be 0.So it will let the delta wrong. We need to avoid this
         * scenario.
         */
-       if (unlikely(!schedstat_val(se->statistics.wait_start)))
+       if (unlikely(!schedstat_val(stats->wait_start)))
                return;
 
-       delta = rq_clock(rq_of(cfs_rq)) - schedstat_val(se->statistics.wait_start);
+       delta = rq_clock(rq_of(cfs_rq)) - schedstat_val(stats->wait_start);
 
        if (entity_is_task(se)) {
                p = task_of(se);
@@ -927,30 +938,33 @@ update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
                         * time stamp can be adjusted to accumulate wait time
                         * prior to migration.
                         */
-                       __schedstat_set(se->statistics.wait_start, delta);
+                       __schedstat_set(stats->wait_start, delta);
                        return;
                }
                trace_sched_stat_wait(p, delta);
        }
 
-       __schedstat_set(se->statistics.wait_max,
-                     max(schedstat_val(se->statistics.wait_max), delta));
-       __schedstat_inc(se->statistics.wait_count);
-       __schedstat_add(se->statistics.wait_sum, delta);
-       __schedstat_set(se->statistics.wait_start, 0);
+       __schedstat_set(stats->wait_max,
+                     max(schedstat_val(stats->wait_max), delta));
+       __schedstat_inc(stats->wait_count);
+       __schedstat_add(stats->wait_sum, delta);
+       __schedstat_set(stats->wait_start, 0);
 }
 
 static inline void
 update_stats_enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
+       struct sched_statistics *stats;
        struct task_struct *tsk = NULL;
        u64 sleep_start, block_start;
 
        if (!schedstat_enabled())
                return;
 
-       sleep_start = schedstat_val(se->statistics.sleep_start);
-       block_start = schedstat_val(se->statistics.block_start);
+       stats = __schedstats_from_se(se);
+
+       sleep_start = schedstat_val(stats->sleep_start);
+       block_start = schedstat_val(stats->block_start);
 
        if (entity_is_task(se))
                tsk = task_of(se);
@@ -961,11 +975,11 @@ update_stats_enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
                if ((s64)delta < 0)
                        delta = 0;
 
-               if (unlikely(delta > schedstat_val(se->statistics.sleep_max)))
-                       __schedstat_set(se->statistics.sleep_max, delta);
+               if (unlikely(delta > schedstat_val(stats->sleep_max)))
+                       __schedstat_set(stats->sleep_max, delta);
 
-               __schedstat_set(se->statistics.sleep_start, 0);
-               __schedstat_add(se->statistics.sum_sleep_runtime, delta);
+               __schedstat_set(stats->sleep_start, 0);
+               __schedstat_add(stats->sum_sleep_runtime, delta);
 
                if (tsk) {
                        account_scheduler_latency(tsk, delta >> 10, 1);
@@ -978,16 +992,16 @@ update_stats_enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
                if ((s64)delta < 0)
                        delta = 0;
 
-               if (unlikely(delta > schedstat_val(se->statistics.block_max)))
-                       __schedstat_set(se->statistics.block_max, delta);
+               if (unlikely(delta > schedstat_val(stats->block_max)))
+                       __schedstat_set(stats->block_max, delta);
 
-               __schedstat_set(se->statistics.block_start, 0);
-               __schedstat_add(se->statistics.sum_sleep_runtime, delta);
+               __schedstat_set(stats->block_start, 0);
+               __schedstat_add(stats->sum_sleep_runtime, delta);
 
                if (tsk) {
                        if (tsk->in_iowait) {
-                               __schedstat_add(se->statistics.iowait_sum, delta);
-                               __schedstat_inc(se->statistics.iowait_count);
+                               __schedstat_add(stats->iowait_sum, delta);
+                               __schedstat_inc(stats->iowait_count);
                                trace_sched_stat_iowait(tsk, delta);
                        }
 
@@ -1049,10 +1063,10 @@ update_stats_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
                /* XXX racy against TTWU */
                state = READ_ONCE(tsk->__state);
                if (state & TASK_INTERRUPTIBLE)
-                       __schedstat_set(se->statistics.sleep_start,
+                       __schedstat_set(tsk->stats.sleep_start,
                                      rq_clock(rq_of(cfs_rq)));
                if (state & TASK_UNINTERRUPTIBLE)
-                       __schedstat_set(se->statistics.block_start,
+                       __schedstat_set(tsk->stats.block_start,
                                      rq_clock(rq_of(cfs_rq)));
        }
 }
@@ -4530,8 +4544,11 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
         */
        if (schedstat_enabled() &&
            rq_of(cfs_rq)->cfs.load.weight >= 2*se->load.weight) {
-               __schedstat_set(se->statistics.slice_max,
-                               max((u64)se->statistics.slice_max,
+               struct sched_statistics *stats;
+
+               stats = __schedstats_from_se(se);
+               __schedstat_set(stats->slice_max,
+                               max((u64)stats->slice_max,
                                    se->sum_exec_runtime - se->prev_sum_exec_runtime));
        }
 
@@ -6046,12 +6063,12 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p,
        if (sched_feat(WA_WEIGHT) && target == nr_cpumask_bits)
                target = wake_affine_weight(sd, p, this_cpu, prev_cpu, sync);
 
-       schedstat_inc(p->se.statistics.nr_wakeups_affine_attempts);
+       schedstat_inc(p->stats.nr_wakeups_affine_attempts);
        if (target == nr_cpumask_bits)
                return prev_cpu;
 
        schedstat_inc(sd->ttwu_move_affine);
-       schedstat_inc(p->se.statistics.nr_wakeups_affine);
+       schedstat_inc(p->stats.nr_wakeups_affine);
        return target;
 }
 
@@ -7855,7 +7872,7 @@ int can_migrate_task(struct task_struct *p, struct lb_env *env)
        if (!cpumask_test_cpu(env->dst_cpu, p->cpus_ptr)) {
                int cpu;
 
-               schedstat_inc(p->se.statistics.nr_failed_migrations_affine);
+               schedstat_inc(p->stats.nr_failed_migrations_affine);
 
                env->flags |= LBF_SOME_PINNED;
 
@@ -7889,7 +7906,7 @@ int can_migrate_task(struct task_struct *p, struct lb_env *env)
        env->flags &= ~LBF_ALL_PINNED;
 
        if (task_running(env->src_rq, p)) {
-               schedstat_inc(p->se.statistics.nr_failed_migrations_running);
+               schedstat_inc(p->stats.nr_failed_migrations_running);
                return 0;
        }
 
@@ -7911,12 +7928,12 @@ int can_migrate_task(struct task_struct *p, struct lb_env *env)
            env->sd->nr_balance_failed > env->sd->cache_nice_tries) {
                if (tsk_cache_hot == 1) {
                        schedstat_inc(env->sd->lb_hot_gained[env->idle]);
-                       schedstat_inc(p->se.statistics.nr_forced_migrations);
+                       schedstat_inc(p->stats.nr_forced_migrations);
                }
                return 1;
        }
 
-       schedstat_inc(p->se.statistics.nr_failed_migrations_hot);
+       schedstat_inc(p->stats.nr_failed_migrations_hot);
        return 0;
 }
 
@@ -11457,7 +11474,7 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
                if (!cfs_rq)
                        goto err;
 
-               se = kzalloc_node(sizeof(struct sched_entity),
+               se = kzalloc_node(sizeof(struct sched_entity_stats),
                                  GFP_KERNEL, cpu_to_node(i));
                if (!se)
                        goto err_free_rq;
index 3daf42a..95a7c3a 100644 (file)
@@ -1009,8 +1009,8 @@ static void update_curr_rt(struct rq *rq)
        if (unlikely((s64)delta_exec <= 0))
                return;
 
-       schedstat_set(curr->se.statistics.exec_max,
-                     max(curr->se.statistics.exec_max, delta_exec));
+       schedstat_set(curr->stats.exec_max,
+                     max(curr->stats.exec_max, delta_exec));
 
        curr->se.sum_exec_runtime += delta_exec;
        account_group_exec_runtime(curr, delta_exec);
index d8f8eb0..fb6022e 100644 (file)
@@ -41,6 +41,7 @@ rq_sched_info_dequeue(struct rq *rq, unsigned long long delta)
 #define   schedstat_val_or_zero(var)   ((schedstat_enabled()) ? (var) : 0)
 
 #else /* !CONFIG_SCHEDSTATS: */
+
 static inline void rq_sched_info_arrive  (struct rq *rq, unsigned long long delta) { }
 static inline void rq_sched_info_dequeue(struct rq *rq, unsigned long long delta) { }
 static inline void rq_sched_info_depart  (struct rq *rq, unsigned long long delta) { }
@@ -53,8 +54,26 @@ static inline void rq_sched_info_depart  (struct rq *rq, unsigned long long delt
 # define   schedstat_set(var, val)     do { } while (0)
 # define   schedstat_val(var)          0
 # define   schedstat_val_or_zero(var)  0
+
 #endif /* CONFIG_SCHEDSTATS */
 
+#ifdef CONFIG_FAIR_GROUP_SCHED
+struct sched_entity_stats {
+       struct sched_entity     se;
+       struct sched_statistics stats;
+} __no_randomize_layout;
+#endif
+
+static inline struct sched_statistics *
+__schedstats_from_se(struct sched_entity *se)
+{
+#ifdef CONFIG_FAIR_GROUP_SCHED
+       if (!entity_is_task(se))
+               return &container_of(se, struct sched_entity_stats, se)->stats;
+#endif
+       return &task_of(se)->stats;
+}
+
 #ifdef CONFIG_PSI
 /*
  * PSI tracks state that persists across sleeps, such as iowaits and
index f988ebe..0b165a2 100644 (file)
@@ -78,8 +78,8 @@ static void put_prev_task_stop(struct rq *rq, struct task_struct *prev)
        if (unlikely((s64)delta_exec < 0))
                delta_exec = 0;
 
-       schedstat_set(curr->se.statistics.exec_max,
-                       max(curr->se.statistics.exec_max, delta_exec));
+       schedstat_set(curr->stats.exec_max,
+                     max(curr->stats.exec_max, delta_exec));
 
        curr->se.sum_exec_runtime += delta_exec;
        account_group_exec_runtime(curr, delta_exec);