From: wangyong <wang.yong12@xxxxxxxxxx>
Subject: delayacct: track delays from memory compact
Delay accounting does not track the delay of memory compact. When there
is not enough free memory, tasks can spend a amount of their time waiting
for compact.
To get the impact of tasks in direct memory compact, measure the delay
when allocating memory through memory compact.
Also update tools/accounting/getdelays.c:
/ # ./getdelays_next -di -p 304
print delayacct stats ON
printing IO accounting
PID 304
CPU count real total virtual total delay total delay average
277 780000000 849039485 18877296 0.068ms
IO count delay total delay average
0 0 0ms
SWAP count delay total delay average
0 0 0ms
RECLAIM count delay total delay average
5 11088812685 2217ms
THRASHING count delay total delay average
0 0 0ms
COMPACT count delay total delay average
3 72758 0ms
watch: read=0, write=0, cancelled_write=0
Link: https://lkml.kernel.org/r/1638619795-71451-1-git-send-email-wang.yong12@xxxxxxxxxx
Signed-off-by: wangyong <wang.yong12@xxxxxxxxxx>
Reviewed-by: Jiang Xuexin <jiang.xuexin@xxxxxxxxxx>
Reviewed-by: Zhang Wenya <zhang.wenya1@xxxxxxxxxx>
Reviewed-by: Yang Yang <yang.yang29@xxxxxxxxxx>
Reviewed-by: Balbir Singh <bsingharora@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/delayacct.h | 28 ++++++++++++++++++++++++++++
include/uapi/linux/taskstats.h | 6 +++++-
kernel/delayacct.c | 15 +++++++++++++++
mm/page_alloc.c | 3 +++
tools/accounting/getdelays.c | 8 +++++++-
5 files changed, 58 insertions(+), 2 deletions(-)
--- a/include/linux/delayacct.h~delayacct-track-delays-from-memory-compact
+++ a/include/linux/delayacct.h
@@ -42,8 +42,12 @@ struct task_delay_info {
u64 thrashing_start;
u64 thrashing_delay; /* wait for thrashing page */
+ u64 compact_start;
+ u64 compact_delay; /* wait for memory compact */
+
u32 freepages_count; /* total count of memory reclaim */
u32 thrashing_count; /* total count of thrash waits */
+ u32 compact_count; /* total count of memory compact */
};
#endif
@@ -72,6 +76,8 @@ extern void __delayacct_thrashing_start(
extern void __delayacct_thrashing_end(void);
extern void __delayacct_swapin_start(void);
extern void __delayacct_swapin_end(void);
+extern void __delayacct_compact_start(void);
+extern void __delayacct_compact_end(void);
static inline void delayacct_tsk_init(struct task_struct *tsk)
{
@@ -170,6 +176,24 @@ static inline void delayacct_swapin_end(
__delayacct_swapin_end();
}
+static inline void delayacct_compact_start(void)
+{
+ if (!static_branch_unlikely(&delayacct_key))
+ return;
+
+ if (current->delays)
+ __delayacct_compact_start();
+}
+
+static inline void delayacct_compact_end(void)
+{
+ if (!static_branch_unlikely(&delayacct_key))
+ return;
+
+ if (current->delays)
+ __delayacct_compact_end();
+}
+
#else
static inline void delayacct_init(void)
{}
@@ -200,6 +224,10 @@ static inline void delayacct_swapin_star
{}
static inline void delayacct_swapin_end(void)
{}
+static inline void delayacct_compact_start(void)
+{}
+static inline void delayacct_compact_end(void)
+{}
#endif /* CONFIG_TASK_DELAY_ACCT */
--- a/include/uapi/linux/taskstats.h~delayacct-track-delays-from-memory-compact
+++ a/include/uapi/linux/taskstats.h
@@ -34,7 +34,7 @@
*/
-#define TASKSTATS_VERSION 10
+#define TASKSTATS_VERSION 11
#define TS_COMM_LEN 32 /* should be >= TASK_COMM_LEN
* in linux/sched.h */
@@ -172,6 +172,10 @@ struct taskstats {
/* v10: 64-bit btime to avoid overflow */
__u64 ac_btime64; /* 64-bit begin time */
+
+ /* Delay waiting for memory compact */
+ __u64 compact_count;
+ __u64 compact_delay_total;
};
--- a/kernel/delayacct.c~delayacct-track-delays-from-memory-compact
+++ a/kernel/delayacct.c
@@ -155,10 +155,13 @@ int delayacct_add_tsk(struct taskstats *
d->freepages_delay_total = (tmp < d->freepages_delay_total) ? 0 : tmp;
tmp = d->thrashing_delay_total + tsk->delays->thrashing_delay;
d->thrashing_delay_total = (tmp < d->thrashing_delay_total) ? 0 : tmp;
+ tmp = d->compact_delay_total + tsk->delays->compact_delay;
+ d->compact_delay_total = (tmp < d->compact_delay_total) ? 0 : tmp;
d->blkio_count += tsk->delays->blkio_count;
d->swapin_count += tsk->delays->swapin_count;
d->freepages_count += tsk->delays->freepages_count;
d->thrashing_count += tsk->delays->thrashing_count;
+ d->compact_count += tsk->delays->compact_count;
raw_spin_unlock_irqrestore(&tsk->delays->lock, flags);
return 0;
@@ -214,3 +217,15 @@ void __delayacct_swapin_end(void)
¤t->delays->swapin_count);
}
+void __delayacct_compact_start(void)
+{
+ current->delays->compact_start = local_clock();
+}
+
+void __delayacct_compact_end(void)
+{
+ delayacct_end(¤t->delays->lock,
+ ¤t->delays->compact_start,
+ ¤t->delays->compact_delay,
+ ¤t->delays->compact_count);
+}
--- a/mm/page_alloc.c~delayacct-track-delays-from-memory-compact
+++ a/mm/page_alloc.c
@@ -74,6 +74,7 @@
#include <linux/padata.h>
#include <linux/khugepaged.h>
#include <linux/buffer_head.h>
+#include <linux/delayacct.h>
#include <asm/sections.h>
#include <asm/tlbflush.h>
#include <asm/div64.h>
@@ -4365,6 +4366,7 @@ __alloc_pages_direct_compact(gfp_t gfp_m
return NULL;
psi_memstall_enter(&pflags);
+ delayacct_compact_start();
noreclaim_flag = memalloc_noreclaim_save();
*compact_result = try_to_compact_pages(gfp_mask, order, alloc_flags, ac,
@@ -4372,6 +4374,7 @@ __alloc_pages_direct_compact(gfp_t gfp_m
memalloc_noreclaim_restore(noreclaim_flag);
psi_memstall_leave(&pflags);
+ delayacct_compact_end();
if (*compact_result == COMPACT_SKIPPED)
return NULL;
--- a/tools/accounting/getdelays.c~delayacct-track-delays-from-memory-compact
+++ a/tools/accounting/getdelays.c
@@ -205,6 +205,8 @@ static void print_delayacct(struct tasks
"RECLAIM %12s%15s%15s\n"
" %15llu%15llu%15llums\n"
"THRASHING%12s%15s%15s\n"
+ " %15llu%15llu%15llums\n"
+ "COMPACT %12s%15s%15s\n"
" %15llu%15llu%15llums\n",
"count", "real total", "virtual total",
"delay total", "delay average",
@@ -228,7 +230,11 @@ static void print_delayacct(struct tasks
"count", "delay total", "delay average",
(unsigned long long)t->thrashing_count,
(unsigned long long)t->thrashing_delay_total,
- average_ms(t->thrashing_delay_total, t->thrashing_count));
+ average_ms(t->thrashing_delay_total, t->thrashing_count),
+ "count", "delay total", "delay average",
+ (unsigned long long)t->compact_count,
+ (unsigned long long)t->compact_delay_total,
+ average_ms(t->compact_delay_total, t->compact_count));
}
static void task_context_switch_counts(struct taskstats *t)
_
