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tick-sched: Preserve number of idle sleeps across CPU hotplug events

PATCH Applied Tim Chen 4 participants 5 messages Jan 22, 2024 – Jan 25, 2024

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Tim Chen

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#0 lore raw

PATCH 1/1 tick-sched: Preserve number of idle sleeps across CPU hotplug events

Patch 71fee48f ("tick-sched: Fix idle and iowait sleeptime accounting vs CPU hotplug") preserved total idle sleep time and iowait sleeptime across CPU hotplug events.

In order to derive average sleep time per sleep event, we should also preserve number of sleeps too in idle_calls and idle_sleeps. Fix that.

Fixes 71fee48f ("tick-sched: Fix idle and iowait sleeptime accounting vs CPU hotplug")
Signed-off-by Tim Chen <[email protected]>
---
 kernel/time/tick-sched.c | 5 +++++
 1 file changed, 5 insertions(+)
kernel/time/tick-sched.c +5 -0
index d2501673028d..01fb50c1b17e 100644
@@ -1577,6 +1577,7 @@ void tick_cancel_sched_timer(int cpu)
 {
 	struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
 	ktime_t idle_sleeptime, iowait_sleeptime;
+	unsigned long idle_calls, idle_sleeps;
 
 # ifdef CONFIG_HIGH_RES_TIMERS
 	if (ts->sched_timer.base)

@@ -1585,9 +1586,13 @@ void tick_cancel_sched_timer(int cpu)
 
 	idle_sleeptime = ts->idle_sleeptime;
 	iowait_sleeptime = ts->iowait_sleeptime;
+	idle_calls = ts->idle_calls;
+	idle_sleeps = ts->idle_sleeps;
 	memset(ts, 0, sizeof(*ts));
 	ts->idle_sleeptime = idle_sleeptime;
 	ts->iowait_sleeptime = iowait_sleeptime;
+	ts->idle_calls = idle_calls;
+	ts->idle_sleeps = idle_sleeps;
 }
 #endif
Signature · 1 line
2.32.0
merge bot Applied
#4 lore raw

[tip: timers/urgent] tick/sched: Preserve number of idle sleeps across CPU hotplug events

In reply to Tim Chen
The following commit has been merged into the timers/urgent branch of tip:

The following commit has been merged into the timers/urgent branch of tip:

Commit-ID:     9a574ea9069be30b835a3da772c039993c43369b
Gitweb:        https://git.kernel.org/tip/9a574ea9069be30b835a3da772c039993c43369b
Author:        Tim Chen <[email protected]>
AuthorDate:    Mon, 22 Jan 2024 15:35:34 -08:00
Committer:     Thomas Gleixner <[email protected]>
CommitterDate: Thu, 25 Jan 2024 09:52:40 +01:00

tick/sched: Preserve number of idle sleeps across CPU hotplug events

Commit 71fee48f ("tick-sched: Fix idle and iowait sleeptime accounting vs CPU hotplug") preserved total idle sleep time and iowait sleeptime across CPU hotplug events.

Similar reasoning applies to the number of idle calls and idle sleeps to get the proper average of sleep time per idle invocation.

Preserve those fields too.

Fixes 71fee48f ("tick-sched: Fix idle and iowait sleeptime accounting vs CPU hotplug")
Signed-off-by Tim Chen <[email protected]>
Signed-off-by Thomas Gleixner <[email protected]>
Cc [email protected]
Link https://lore.kernel.org/r/[email protected] open here
---
 kernel/time/tick-sched.c | 5 +++++
 1 file changed, 5 insertions(+)
kernel/time/tick-sched.c +5 -0
index d250167..01fb50c 100644
@@ -1577,6 +1577,7 @@ void tick_cancel_sched_timer(int cpu)
 {
 	struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
 	ktime_t idle_sleeptime, iowait_sleeptime;
+	unsigned long idle_calls, idle_sleeps;
 
 # ifdef CONFIG_HIGH_RES_TIMERS
 	if (ts->sched_timer.base)

@@ -1585,9 +1586,13 @@ void tick_cancel_sched_timer(int cpu)
 
 	idle_sleeptime = ts->idle_sleeptime;
 	iowait_sleeptime = ts->iowait_sleeptime;
+	idle_calls = ts->idle_calls;
+	idle_sleeps = ts->idle_sleeps;
 	memset(ts, 0, sizeof(*ts));
 	ts->idle_sleeptime = idle_sleeptime;
 	ts->iowait_sleeptime = iowait_sleeptime;
+	ts->idle_calls = idle_calls;
+	ts->idle_sleeps = idle_sleeps;
 }
 #endif