2020-12-03 06:50:00

by Yunfeng Ye

[permalink] [raw]
Subject: [PATCH 2/2] sched: Split the function show_schedstat()

The schedstat include runqueue-specific stats and domain-specific stats,
so split it into two functions, show_rqstat() and show_domainstat().

No functional changes.

Signed-off-by: Yunfeng Ye <[email protected]>
---
kernel/sched/stats.c | 101 +++++++++++++++++++++++--------------------
1 file changed, 54 insertions(+), 47 deletions(-)

diff --git a/kernel/sched/stats.c b/kernel/sched/stats.c
index e99403df3f90..ef75e7d64d32 100644
--- a/kernel/sched/stats.c
+++ b/kernel/sched/stats.c
@@ -12,61 +12,68 @@
*/
#define SCHEDSTAT_VERSION 15

-static int show_schedstat(struct seq_file *seq, void *v)
+static void show_domainstat(struct seq_file *seq, int cpu)
+{
+#ifdef CONFIG_SMP
+ struct sched_domain *sd;
+ int dcount = 0;
+
+ /* domain-specific stats */
+ rcu_read_lock();
+ for_each_domain(cpu, sd) {
+ enum cpu_idle_type itype;
+
+ seq_printf(seq, "domain%d %*pb", dcount++,
+ cpumask_pr_args(sched_domain_span(sd)));
+ for (itype = CPU_IDLE; itype < CPU_MAX_IDLE_TYPES;
+ itype++) {
+ seq_printf(seq, " %u %u %u %u %u %u %u %u",
+ sd->lb_count[itype],
+ sd->lb_balanced[itype],
+ sd->lb_failed[itype],
+ sd->lb_imbalance[itype],
+ sd->lb_gained[itype],
+ sd->lb_hot_gained[itype],
+ sd->lb_nobusyq[itype],
+ sd->lb_nobusyg[itype]);
+ }
+ seq_printf(seq,
+ " %u %u %u %u %u %u %u %u %u %u %u %u\n",
+ sd->alb_count, sd->alb_failed, sd->alb_pushed,
+ sd->sbe_count, sd->sbe_balanced, sd->sbe_pushed,
+ sd->sbf_count, sd->sbf_balanced, sd->sbf_pushed,
+ sd->ttwu_wake_remote, sd->ttwu_move_affine,
+ sd->ttwu_move_balance);
+ }
+ rcu_read_unlock();
+#endif
+}
+
+static void show_rqstat(struct seq_file *seq, int cpu)
{
- int cpu;
+ struct rq *rq = cpu_rq(cpu);
+
+ /* runqueue-specific stats */
+ seq_printf(seq,
+ "cpu%d %u 0 %u %u %u %u %llu %llu %lu\n",
+ cpu, rq->yld_count,
+ rq->sched_count, rq->sched_goidle,
+ rq->ttwu_count, rq->ttwu_local,
+ rq->rq_cpu_time,
+ rq->rq_sched_info.run_delay, rq->rq_sched_info.pcount);
+}

+static int show_schedstat(struct seq_file *seq, void *v)
+{
if (v == (void *)1) {
seq_printf(seq, "version %d\n", SCHEDSTAT_VERSION);
seq_printf(seq, "timestamp %lu\n", jiffies);
} else {
- struct rq *rq;
-#ifdef CONFIG_SMP
- struct sched_domain *sd;
- int dcount = 0;
-#endif
- cpu = (unsigned long)(v - 2);
- rq = cpu_rq(cpu);
+ int cpu = (unsigned long)(v - 2);

- /* runqueue-specific stats */
- seq_printf(seq,
- "cpu%d %u 0 %u %u %u %u %llu %llu %lu\n",
- cpu, rq->yld_count,
- rq->sched_count, rq->sched_goidle,
- rq->ttwu_count, rq->ttwu_local,
- rq->rq_cpu_time,
- rq->rq_sched_info.run_delay, rq->rq_sched_info.pcount);
+ show_rqstat(seq, cpu);
+ show_domainstat(seq, cpu);

-#ifdef CONFIG_SMP
- /* domain-specific stats */
- rcu_read_lock();
- for_each_domain(cpu, sd) {
- enum cpu_idle_type itype;
-
- seq_printf(seq, "domain%d %*pb", dcount++,
- cpumask_pr_args(sched_domain_span(sd)));
- for (itype = CPU_IDLE; itype < CPU_MAX_IDLE_TYPES;
- itype++) {
- seq_printf(seq, " %u %u %u %u %u %u %u %u",
- sd->lb_count[itype],
- sd->lb_balanced[itype],
- sd->lb_failed[itype],
- sd->lb_imbalance[itype],
- sd->lb_gained[itype],
- sd->lb_hot_gained[itype],
- sd->lb_nobusyq[itype],
- sd->lb_nobusyg[itype]);
- }
- seq_printf(seq,
- " %u %u %u %u %u %u %u %u %u %u %u %u\n",
- sd->alb_count, sd->alb_failed, sd->alb_pushed,
- sd->sbe_count, sd->sbe_balanced, sd->sbe_pushed,
- sd->sbf_count, sd->sbf_balanced, sd->sbf_pushed,
- sd->ttwu_wake_remote, sd->ttwu_move_affine,
- sd->ttwu_move_balance);
- }
- rcu_read_unlock();
-#endif
}
return 0;
}
--
2.18.4


2020-12-03 09:46:34

by Mel Gorman

[permalink] [raw]
Subject: Re: [PATCH 2/2] sched: Split the function show_schedstat()

On Thu, Dec 03, 2020 at 02:47:14PM +0800, Yunfeng Ye wrote:
> The schedstat include runqueue-specific stats and domain-specific stats,
> so split it into two functions, show_rqstat() and show_domainstat().
>
> No functional changes.
>
> Signed-off-by: Yunfeng Ye <[email protected]>

Why?

I could understand if there was a follow-up patch that adjusted some
subset or there was a difference in checking for schedstat_enabled,
locking or inserting new schedstat information. This can happen in the
general case when the end result is easier to review here it seems to be
just moving code around.

--
Mel Gorman
SUSE Labs

2020-12-04 01:25:24

by Yunfeng Ye

[permalink] [raw]
Subject: Re: [PATCH 2/2] sched: Split the function show_schedstat()



On 2020/12/3 17:42, Mel Gorman wrote:
> On Thu, Dec 03, 2020 at 02:47:14PM +0800, Yunfeng Ye wrote:
>> The schedstat include runqueue-specific stats and domain-specific stats,
>> so split it into two functions, show_rqstat() and show_domainstat().
>>
>> No functional changes.
>>
>> Signed-off-by: Yunfeng Ye <[email protected]>
>
> Why?
>
> I could understand if there was a follow-up patch that adjusted some
> subset or there was a difference in checking for schedstat_enabled,
> locking or inserting new schedstat information. This can happen in the
> general case when the end result is easier to review here it seems to be
> just moving code around.
>
The rqstat and domainstat is independent state information. so I think
split it into two individual function is clearer.

Thanks.

2020-12-04 09:45:29

by Mel Gorman

[permalink] [raw]
Subject: Re: [PATCH 2/2] sched: Split the function show_schedstat()

On Fri, Dec 04, 2020 at 09:22:34AM +0800, Yunfeng Ye wrote:
>
>
> On 2020/12/3 17:42, Mel Gorman wrote:
> > On Thu, Dec 03, 2020 at 02:47:14PM +0800, Yunfeng Ye wrote:
> >> The schedstat include runqueue-specific stats and domain-specific stats,
> >> so split it into two functions, show_rqstat() and show_domainstat().
> >>
> >> No functional changes.
> >>
> >> Signed-off-by: Yunfeng Ye <[email protected]>
> >
> > Why?
> >
> > I could understand if there was a follow-up patch that adjusted some
> > subset or there was a difference in checking for schedstat_enabled,
> > locking or inserting new schedstat information. This can happen in the
> > general case when the end result is easier to review here it seems to be
> > just moving code around.
> >
> The rqstat and domainstat is independent state information. so I think
> split it into two individual function is clearer.
>

The comments and the names of the structures being accessesd is sufficient
to make it clear.

--
Mel Gorman
SUSE Labs

2020-12-05 02:34:50

by Yunfeng Ye

[permalink] [raw]
Subject: Re: [PATCH 2/2] sched: Split the function show_schedstat()



On 2020/12/4 17:40, Mel Gorman wrote:
> On Fri, Dec 04, 2020 at 09:22:34AM +0800, Yunfeng Ye wrote:
>>
>>
>> On 2020/12/3 17:42, Mel Gorman wrote:
>>> On Thu, Dec 03, 2020 at 02:47:14PM +0800, Yunfeng Ye wrote:
>>>> The schedstat include runqueue-specific stats and domain-specific stats,
>>>> so split it into two functions, show_rqstat() and show_domainstat().
>>>>
>>>> No functional changes.
>>>>
>>>> Signed-off-by: Yunfeng Ye <[email protected]>
>>>
>>> Why?
>>>
>>> I could understand if there was a follow-up patch that adjusted some
>>> subset or there was a difference in checking for schedstat_enabled,
>>> locking or inserting new schedstat information. This can happen in the
>>> general case when the end result is easier to review here it seems to be
>>> just moving code around.
>>>
>> The rqstat and domainstat is independent state information. so I think
>> split it into two individual function is clearer.
>>
>
> The comments and the names of the structures being accessesd is sufficient
> to make it clear.
>
ok, thanks.