From: Andrey Ryabinin <[email protected]> Add schdeuling latncies to /proc/<pid>/vz_latency. They are the same as alloc latencies - total cumulative latency, number of schedule events, and latency maximum in the last 2 minutes.
The sysctl kernel.sched_schedstats must be enabled to see these stats. https://jira.sw.ru/browse/PSBM-87797 Signed-off-by: Andrey Ryabinin <[email protected]> Cc: Pavel Borzenkov <[email protected]> Reviewed-by: Denis V. Lunev <[email protected]> Rebase to vz8: - Add new argument to update_sched_lat. It was reworked during previous ports to have only time delta, which is unsufficient for update_maxlat. (cherry-picked from 0ed8df6d0d18e079369cd004ff47caf119c86edb) Signed-off-by: Andrey Zhadchenko <[email protected]> --- fs/proc/base.c | 18 ++++++++++++++++-- include/linux/kstat.h | 5 +++++ include/linux/sched.h | 2 +- include/linux/sched/signal.h | 2 +- kernel/exit.c | 6 ++---- kernel/sched/fair.c | 13 +++++++++---- 6 files changed, 34 insertions(+), 12 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index cf8afe1..4860efc 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -538,13 +538,18 @@ static void lastlat_seq_show(struct seq_file *m, "allocatomic:", "alloc:", "allocmp:", + "scheduling:", }; static const int alloc_types[] = { KSTAT_ALLOCSTAT_ATOMIC, KSTAT_ALLOCSTAT_LOW, KSTAT_ALLOCSTAT_LOW_MP, + KSTAT_SCHED, }; +extern struct static_key sched_schedstats; +# define schedstat_enabled() static_key_false(&sched_schedstats) + static int proc_tid_vz_lat(struct seq_file *m, struct pid_namespace *ns, struct pid *pid, struct task_struct *task) { @@ -553,9 +558,13 @@ static int proc_tid_vz_lat(struct seq_file *m, struct pid_namespace *ns, seq_printf(m, "%-12s %20s %20s %20s\n", "Type", "Total_lat", "Calls", "Max (2min)"); - for (i = 0; i < ARRAY_SIZE(alloc_types); i++) + for (i = 0; i < ARRAY_SIZE(alloc_types); i++) { + if (alloc_types[i] == KSTAT_SCHED && !schedstat_enabled()) + continue; lastlat_seq_show(m, alloc_descr[i], &task->alloc_lat[alloc_types[i]]); + } + return 0; } @@ -595,15 +604,20 @@ static int proc_tgid_vz_lat(struct seq_file *m, struct pid_namespace *ns, maxlats[i] = maxlat; } + unlock_task_sighand(task, &flags); } seq_printf(m, "%-12s %20s %20s %20s\n", "Type", "Total_lat", "Calls", "Max (2min)"); - for (i = 0; i < ARRAY_SIZE(alloc_types); i++) + for (i = 0; i < ARRAY_SIZE(alloc_types); i++) { + if (alloc_types[i] == KSTAT_SCHED && !schedstat_enabled()) + continue; + seq_printf(m, "%-12s %20Lu %20Lu %20Lu\n", alloc_descr[i], lat[i], count[i], maxlats[i]); + } return 0; } diff --git a/include/linux/kstat.h b/include/linux/kstat.h index 4a49337..97a0f9b 100644 --- a/include/linux/kstat.h +++ b/include/linux/kstat.h @@ -8,6 +8,8 @@ enum { KSTAT_ALLOCSTAT_LOW_MP, KSTAT_ALLOCSTAT_HIGH_MP, KSTAT_ALLOCSTAT_NR, + KSTAT_SCHED = KSTAT_ALLOCSTAT_NR, + KSTAT_NR, }; struct kstat_perf_snap_struct { @@ -46,4 +48,7 @@ struct kstat_lat_pcpu_struct { u64 avg[3]; }; +void update_maxlat(struct kstat_lat_snap_struct *alloc_lat, + u64 lat, unsigned long time); + #endif diff --git a/include/linux/sched.h b/include/linux/sched.h index 72b3f40..f8a0e14 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1126,7 +1126,7 @@ struct task_struct { struct tlbflush_unmap_batch tlb_ubc; #ifdef CONFIG_VE - struct kstat_lat_snap_struct alloc_lat[KSTAT_ALLOCSTAT_NR]; + struct kstat_lat_snap_struct alloc_lat[KSTAT_NR]; #endif RH_KABI_REPLACE(struct rcu_head rcu, union { diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h index adfe9cc..1f4a0c5 100644 --- a/include/linux/sched/signal.h +++ b/include/linux/sched/signal.h @@ -212,7 +212,7 @@ struct signal_struct { struct taskstats *stats; #endif #ifdef CONFIG_VE - struct kstat_lat_snap_struct alloc_lat[KSTAT_ALLOCSTAT_NR]; + struct kstat_lat_snap_struct alloc_lat[KSTAT_NR]; #endif #ifdef CONFIG_AUDIT unsigned audit_tty; diff --git a/kernel/exit.c b/kernel/exit.c index d105044..55c1e50 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -723,16 +723,13 @@ static void check_stack_usage(void) static inline void check_stack_usage(void) {} #endif -void update_maxlat(struct kstat_lat_snap_struct *alloc_lat, - u64 lat, unsigned long time); - void kstat_add_dying(struct task_struct *tsk) { #ifdef CONFIG_VE int i; spin_lock_irq(&tsk->sighand->siglock); - for (i = 0; i < KSTAT_ALLOCSTAT_NR; i++) { + for (i = 0; i < KSTAT_NR; i++) { int j; tsk->signal->alloc_lat[i].totlat += tsk->alloc_lat[i].totlat; @@ -746,6 +743,7 @@ void kstat_add_dying(struct task_struct *tsk) } } } + spin_unlock_irq(&tsk->sighand->siglock); #endif } diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 8f22066..da2e976 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -947,11 +947,15 @@ static void update_curr_fair(struct rq *rq) __schedstat_set(se->statistics.wait_start, wait_start); } -static inline void update_sched_lat(struct task_struct *t, u64 delta) +static inline void update_sched_lat(struct task_struct *t, u64 delta, u64 now) { #ifdef CONFIG_VE KSTAT_LAT_PCPU_ADD(&kstat_glob.sched_lat, delta); KSTAT_LAT_PCPU_ADD(&t->task_ve->sched_lat_ve, delta); + + t->alloc_lat[KSTAT_SCHED].totlat += delta; + t->alloc_lat[KSTAT_SCHED].count++; + update_maxlat(&t->alloc_lat[KSTAT_SCHED], delta, now); #endif } @@ -959,12 +963,13 @@ static inline void update_sched_lat(struct task_struct *t, u64 delta) update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se) { struct task_struct *p; - u64 delta; + u64 delta, now; if (!schedstat_enabled()) return; - delta = rq_clock(rq_of(cfs_rq)) - schedstat_val(se->statistics.wait_start); + now = rq_clock(rq_of(cfs_rq)); + delta = now - schedstat_val(se->statistics.wait_start); if (entity_is_task(se)) { p = task_of(se); @@ -978,7 +983,7 @@ static inline void update_sched_lat(struct task_struct *t, u64 delta) return; } trace_sched_stat_wait(p, delta); - update_sched_lat(p, delta); + update_sched_lat(p, delta, now); } __schedstat_set(se->statistics.wait_max, -- 1.8.3.1 _______________________________________________ Devel mailing list [email protected] https://lists.openvz.org/mailman/listinfo/devel
