diff options
| author | Shile Zhang <shile.zhang@nokia.com> | 2017-01-28 22:00:49 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-07-09 09:35:08 +0200 |
| commit | e9bc62b17b65523f8e714348a652fd8993fad833 (patch) | |
| tree | 1b0426140886149de563f2a954a2ce1ec123e4d9 | |
| parent | fba0d6b2d4c2a858a6784e8c577bb98da0dd515e (diff) | |
sched/rt: Show the 'sched_rr_timeslice' SCHED_RR timeslice tuning knob in milliseconds
[ Upstream commit 975e155ed8732cb81f55c021c441ae662dd040b5 ]
We added the 'sched_rr_timeslice_ms' SCHED_RR tuning knob in this commit:
ce0dbbbb30ae ("sched/rt: Add a tuning knob to allow changing SCHED_RR timeslice")
... which name suggests to users that it's in milliseconds, while in reality
it's being set in milliseconds but the result is shown in jiffies.
This is obviously confusing when HZ is not 1000, it makes it appear like the
value set failed, such as HZ=100:
root# echo 100 > /proc/sys/kernel/sched_rr_timeslice_ms
root# cat /proc/sys/kernel/sched_rr_timeslice_ms
10
Fix this to be milliseconds all around.
Signed-off-by: Shile Zhang <shile.zhang@nokia.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1485612049-20923-1-git-send-email-shile.zhang@nokia.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | include/linux/sched/sysctl.h | 1 | ||||
| -rw-r--r-- | kernel/sched/core.c | 5 | ||||
| -rw-r--r-- | kernel/sched/rt.c | 1 | ||||
| -rw-r--r-- | kernel/sysctl.c | 2 |
4 files changed, 6 insertions, 3 deletions
diff --git a/include/linux/sched/sysctl.h b/include/linux/sched/sysctl.h index c9e4731cf10b..7fc36ebc5de3 100644 --- a/include/linux/sched/sysctl.h +++ b/include/linux/sched/sysctl.h @@ -81,6 +81,7 @@ extern unsigned int sysctl_sched_cfs_bandwidth_slice; extern unsigned int sysctl_sched_autogroup_enabled; #endif +extern int sysctl_sched_rr_timeslice; extern int sched_rr_timeslice; extern int sched_rr_handler(struct ctl_table *table, int write, diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 14a87c1f3a3a..4a0a754f24c8 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -8266,8 +8266,9 @@ int sched_rr_handler(struct ctl_table *table, int write, /* make sure that internally we keep jiffies */ /* also, writing zero resets timeslice to default */ if (!ret && write) { - sched_rr_timeslice = sched_rr_timeslice <= 0 ? - RR_TIMESLICE : msecs_to_jiffies(sched_rr_timeslice); + sched_rr_timeslice = + sysctl_sched_rr_timeslice <= 0 ? RR_TIMESLICE : + msecs_to_jiffies(sysctl_sched_rr_timeslice); } mutex_unlock(&mutex); return ret; diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 801b4ec40702..5ee5740635f3 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -9,6 +9,7 @@ #include <linux/irq_work.h> int sched_rr_timeslice = RR_TIMESLICE; +int sysctl_sched_rr_timeslice = (MSEC_PER_SEC / HZ) * RR_TIMESLICE; static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index c2dddd335d06..ecbb1b764a82 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -412,7 +412,7 @@ static struct ctl_table kern_table[] = { }, { .procname = "sched_rr_timeslice_ms", - .data = &sched_rr_timeslice, + .data = &sysctl_sched_rr_timeslice, .maxlen = sizeof(int), .mode = 0644, .proc_handler = sched_rr_handler, |