lkml.org 
[lkml]   [2021]   [Jul]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3/9] sched/fair: Track efficiency of select_idle_core
Date
Add efficiency tracking for select_idle_core.

MMTests uses this to generate additional metrics.

SIS Core Search: The number of times a domain was searched for an idle core

SIS Core Hit: Idle core search success.

SIS Core Miss: Idle core search miss.

SIS Core Search Eff: The percentage of searches that were successful

Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
---
kernel/sched/debug.c | 2 ++
kernel/sched/fair.c | 2 ++
kernel/sched/sched.h | 2 ++
kernel/sched/stats.c | 7 ++++---
4 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 1ec87b7bb6a9..26bdc455e4f4 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -744,6 +744,8 @@ do { \
P(sis_failed);
P(sis_recent_hit);
P(sis_recent_miss);
+ P(sis_core_search);
+ P(sis_core_failed);
}
#undef P

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 4d48dc08a49b..4e2979b73cec 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -6138,6 +6138,7 @@ static int select_idle_core(struct task_struct *p, int core, struct cpumask *cpu
if (!static_branch_likely(&sched_smt_present))
return __select_idle_cpu(core, p);

+ schedstat_inc(this_rq()->sis_core_search);
for_each_cpu(cpu, cpu_smt_mask(core)) {
schedstat_inc(this_rq()->sis_scanned);
if (!available_idle_cpu(cpu)) {
@@ -6158,6 +6159,7 @@ static int select_idle_core(struct task_struct *p, int core, struct cpumask *cpu
if (idle)
return core;

+ schedstat_inc(this_rq()->sis_core_failed);
cpumask_andnot(cpus, cpus, cpu_smt_mask(core));
return -1;
}
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 1c04d7a97dbe..e31179e6c6ff 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1080,6 +1080,8 @@ struct rq {
unsigned int sis_failed;
unsigned int sis_recent_hit;
unsigned int sis_recent_miss;
+ unsigned int sis_core_search;
+ unsigned int sis_core_failed;
#endif

#ifdef CONFIG_CPU_IDLE
diff --git a/kernel/sched/stats.c b/kernel/sched/stats.c
index 1aa648edb88b..5672f3dc7002 100644
--- a/kernel/sched/stats.c
+++ b/kernel/sched/stats.c
@@ -10,7 +10,7 @@
* Bump this up when changing the output format or the meaning of an existing
* format, so that tools can adapt (or abort)
*/
-#define SCHEDSTAT_VERSION 17
+#define SCHEDSTAT_VERSION 18

static int show_schedstat(struct seq_file *seq, void *v)
{
@@ -30,7 +30,7 @@ static int show_schedstat(struct seq_file *seq, void *v)

/* runqueue-specific stats */
seq_printf(seq,
- "cpu%d %u 0 %u %u %u %u %llu %llu %lu %u %u %u %u %u %u",
+ "cpu%d %u 0 %u %u %u %u %llu %llu %lu %u %u %u %u %u %u %u %u",
cpu, rq->yld_count,
rq->sched_count, rq->sched_goidle,
rq->ttwu_count, rq->ttwu_local,
@@ -38,7 +38,8 @@ static int show_schedstat(struct seq_file *seq, void *v)
rq->rq_sched_info.run_delay, rq->rq_sched_info.pcount,
rq->sis_search, rq->sis_domain_search,
rq->sis_scanned, rq->sis_failed,
- rq->sis_recent_hit, rq->sis_recent_miss);
+ rq->sis_recent_hit, rq->sis_recent_miss,
+ rq->sis_core_search, rq->sis_core_failed);

seq_printf(seq, "\n");

--
2.26.2
\
 
 \ /
  Last update: 2021-07-26 12:24    [W:0.911 / U:0.020 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site