This is a note to let you know that I've just added the patch titled tick/sched: Preserve number of idle sleeps across CPU hotplug events to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tick-sched-preserve-number-of-idle-sleeps-across-cpu-hotplug-events.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 9a574ea9069be30b835a3da772c039993c43369b Mon Sep 17 00:00:00 2001 From: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx> Date: Mon, 22 Jan 2024 15:35:34 -0800 Subject: tick/sched: Preserve number of idle sleeps across CPU hotplug events From: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx> commit 9a574ea9069be30b835a3da772c039993c43369b upstream. 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 <tim.c.chen@xxxxxxxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Link: https://lore.kernel.org/r/20240122233534.3094238-1-tim.c.chen@xxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/time/tick-sched.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -1557,6 +1557,7 @@ 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) @@ -1565,9 +1566,13 @@ 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 Patches currently in stable-queue which might be from tim.c.chen@xxxxxxxxxxxxxxx are queue-6.1/tick-sched-preserve-number-of-idle-sleeps-across-cpu-hotplug-events.patch