diff options
| author | Wang Yaxin <wang.yaxin@zte.com.cn> | 2024-12-20 17:31:05 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-01-12 20:21:16 -0800 |
| commit | f65c64f311ee2f1ddc1eb395ed8b20e6b9d14e85 (patch) | |
| tree | ca352bc26ec78239c7af48bfb5ecf57436808b85 /kernel/delayacct.c | |
| parent | 7e70433c2bf542e10c6e40084d8adb7325dc71cb (diff) | |
delayacct: add delay min to record delay peak
Delay accounting can now calculate the average delay of processes, detect
the overall system load, and also record the 'delay max' to identify
potential abnormal delays. However, 'delay min' can help us identify
another useful delay peak. By comparing the difference between 'delay
max' and 'delay min', we can understand the optimization space for
latency, providing a reference for the optimization of latency
performance.
Use case
=========
bash-4.4# ./getdelays -d -t 242
print delayacct stats ON
TGID 242
CPU count real total virtual total delay total delay average delay max delay min
39 156000000 156576579 2111069 0.054ms 0.212296ms 0.031307ms
IO count delay total delay average delay max delay min
0 0 0.000ms 0.000000ms 0.000000ms
SWAP count delay total delay average delay max delay min
0 0 0.000ms 0.000000ms 0.000000ms
RECLAIM count delay total delay average delay max delay min
0 0 0.000ms 0.000000ms 0.000000ms
THRASHING count delay total delay average delay max delay min
0 0 0.000ms 0.000000ms 0.000000ms
COMPACT count delay total delay average delay max delay min
0 0 0.000ms 0.000000ms 0.000000ms
WPCOPY count delay total delay average delay max delay min
156 11215873 0.072ms 0.207403ms 0.033913ms
IRQ count delay total delay average delay max delay min
0 0 0.000ms 0.000000ms 0.000000ms
Link: https://lkml.kernel.org/r/20241220173105906EOdsPhzjMLYNJJBqgz1ga@zte.com.cn
Co-developed-by: Wang Yong <wang.yong12@zte.com.cn>
Signed-off-by: Wang Yong <wang.yong12@zte.com.cn>
Co-developed-by: xu xin <xu.xin16@zte.com.cn>
Signed-off-by: xu xin <xu.xin16@zte.com.cn>
Signed-off-by: Wang Yaxin <wang.yaxin@zte.com.cn>
Co-developed-by: Kun Jiang <jiang.kun2@zte.com.cn>
Signed-off-by: Kun Jiang <jiang.kun2@zte.com.cn>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Fan Yu <fan.yu9@zte.com.cn>
Cc: Peilin He <he.peilin@zte.com.cn>
Cc: tuqiang <tu.qiang35@zte.com.cn>
Cc: ye xingchen <ye.xingchen@zte.com.cn>
Cc: Yunkai Zhang <zhang.yunkai@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'kernel/delayacct.c')
| -rw-r--r-- | kernel/delayacct.c | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/kernel/delayacct.c b/kernel/delayacct.c index 23212a0c88e4..b238eb8c6573 100644 --- a/kernel/delayacct.c +++ b/kernel/delayacct.c @@ -95,7 +95,7 @@ void __delayacct_tsk_init(struct task_struct *tsk) * Finish delay accounting for a statistic using its timestamps (@start), * accumulator (@total) and @count */ -static void delayacct_end(raw_spinlock_t *lock, u64 *start, u64 *total, u32 *count, u64 *max) +static void delayacct_end(raw_spinlock_t *lock, u64 *start, u64 *total, u32 *count, u64 *max, u64 *min) { s64 ns = local_clock() - *start; unsigned long flags; @@ -106,6 +106,8 @@ static void delayacct_end(raw_spinlock_t *lock, u64 *start, u64 *total, u32 *cou (*count)++; if (ns > *max) *max = ns; + if (*min == 0 || ns < *min) + *min = ns; raw_spin_unlock_irqrestore(lock, flags); } } @@ -125,7 +127,8 @@ void __delayacct_blkio_end(struct task_struct *p) &p->delays->blkio_start, &p->delays->blkio_delay, &p->delays->blkio_count, - &p->delays->blkio_delay_max); + &p->delays->blkio_delay_max, + &p->delays->blkio_delay_min); } int delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk) @@ -157,6 +160,7 @@ int delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk) d->cpu_count += t1; d->cpu_delay_max = tsk->sched_info.max_run_delay; + d->cpu_delay_min = tsk->sched_info.min_run_delay; tmp = (s64)d->cpu_delay_total + t2; d->cpu_delay_total = (tmp < (s64)d->cpu_delay_total) ? 0 : tmp; tmp = (s64)d->cpu_run_virtual_total + t3; @@ -170,24 +174,31 @@ int delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk) /* zero XXX_total, non-zero XXX_count implies XXX stat overflowed */ raw_spin_lock_irqsave(&tsk->delays->lock, flags); d->blkio_delay_max = tsk->delays->blkio_delay_max; + d->blkio_delay_min = tsk->delays->blkio_delay_min; tmp = d->blkio_delay_total + tsk->delays->blkio_delay; d->blkio_delay_total = (tmp < d->blkio_delay_total) ? 0 : tmp; d->swapin_delay_max = tsk->delays->swapin_delay_max; + d->swapin_delay_min = tsk->delays->swapin_delay_min; tmp = d->swapin_delay_total + tsk->delays->swapin_delay; d->swapin_delay_total = (tmp < d->swapin_delay_total) ? 0 : tmp; d->freepages_delay_max = tsk->delays->freepages_delay_max; + d->freepages_delay_min = tsk->delays->freepages_delay_min; tmp = d->freepages_delay_total + tsk->delays->freepages_delay; d->freepages_delay_total = (tmp < d->freepages_delay_total) ? 0 : tmp; d->thrashing_delay_max = tsk->delays->thrashing_delay_max; + d->thrashing_delay_min = tsk->delays->thrashing_delay_min; tmp = d->thrashing_delay_total + tsk->delays->thrashing_delay; d->thrashing_delay_total = (tmp < d->thrashing_delay_total) ? 0 : tmp; d->compact_delay_max = tsk->delays->compact_delay_max; + d->compact_delay_min = tsk->delays->compact_delay_min; tmp = d->compact_delay_total + tsk->delays->compact_delay; d->compact_delay_total = (tmp < d->compact_delay_total) ? 0 : tmp; d->wpcopy_delay_max = tsk->delays->wpcopy_delay_max; + d->wpcopy_delay_min = tsk->delays->wpcopy_delay_min; tmp = d->wpcopy_delay_total + tsk->delays->wpcopy_delay; d->wpcopy_delay_total = (tmp < d->wpcopy_delay_total) ? 0 : tmp; d->irq_delay_max = tsk->delays->irq_delay_max; + d->irq_delay_min = tsk->delays->irq_delay_min; tmp = d->irq_delay_total + tsk->delays->irq_delay; d->irq_delay_total = (tmp < d->irq_delay_total) ? 0 : tmp; d->blkio_count += tsk->delays->blkio_count; @@ -224,7 +235,8 @@ void __delayacct_freepages_end(void) ¤t->delays->freepages_start, ¤t->delays->freepages_delay, ¤t->delays->freepages_count, - ¤t->delays->freepages_delay_max); + ¤t->delays->freepages_delay_max, + ¤t->delays->freepages_delay_min); } void __delayacct_thrashing_start(bool *in_thrashing) @@ -247,7 +259,8 @@ void __delayacct_thrashing_end(bool *in_thrashing) ¤t->delays->thrashing_start, ¤t->delays->thrashing_delay, ¤t->delays->thrashing_count, - ¤t->delays->thrashing_delay_max); + ¤t->delays->thrashing_delay_max, + ¤t->delays->thrashing_delay_min); } void __delayacct_swapin_start(void) @@ -261,7 +274,8 @@ void __delayacct_swapin_end(void) ¤t->delays->swapin_start, ¤t->delays->swapin_delay, ¤t->delays->swapin_count, - ¤t->delays->swapin_delay_max); + ¤t->delays->swapin_delay_max, + ¤t->delays->swapin_delay_min); } void __delayacct_compact_start(void) @@ -275,7 +289,8 @@ void __delayacct_compact_end(void) ¤t->delays->compact_start, ¤t->delays->compact_delay, ¤t->delays->compact_count, - ¤t->delays->compact_delay_max); + ¤t->delays->compact_delay_max, + ¤t->delays->compact_delay_min); } void __delayacct_wpcopy_start(void) @@ -289,7 +304,8 @@ void __delayacct_wpcopy_end(void) ¤t->delays->wpcopy_start, ¤t->delays->wpcopy_delay, ¤t->delays->wpcopy_count, - ¤t->delays->wpcopy_delay_max); + ¤t->delays->wpcopy_delay_max, + ¤t->delays->wpcopy_delay_min); } void __delayacct_irq(struct task_struct *task, u32 delta) @@ -301,6 +317,8 @@ void __delayacct_irq(struct task_struct *task, u32 delta) task->delays->irq_count++; if (delta > task->delays->irq_delay_max) task->delays->irq_delay_max = delta; + if (delta && (!task->delays->irq_delay_min || delta < task->delays->irq_delay_min)) + task->delays->irq_delay_min = delta; raw_spin_unlock_irqrestore(&task->delays->lock, flags); } |