diff options
Diffstat (limited to 'debian/patches-rt/0112-sched-Disable-TTWU_QUEUE-on-RT.patch')
| -rw-r--r-- | debian/patches-rt/0112-sched-Disable-TTWU_QUEUE-on-RT.patch | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/debian/patches-rt/0112-sched-Disable-TTWU_QUEUE-on-RT.patch b/debian/patches-rt/0112-sched-Disable-TTWU_QUEUE-on-RT.patch new file mode 100644 index 000000000..8e44536b2 --- /dev/null +++ b/debian/patches-rt/0112-sched-Disable-TTWU_QUEUE-on-RT.patch @@ -0,0 +1,38 @@ +From 31cdcd445b6fbf09238e8e3a25c2dd72be0bb187 Mon Sep 17 00:00:00 2001 +From: Thomas Gleixner <tglx@linutronix.de> +Date: Tue, 13 Sep 2011 16:42:35 +0200 +Subject: [PATCH 112/347] sched: Disable TTWU_QUEUE on RT +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.246-rt110.tar.xz + +The queued remote wakeup mechanism can introduce rather large +latencies if the number of migrated tasks is high. Disable it for RT. + +Signed-off-by: Thomas Gleixner <tglx@linutronix.de> +--- + kernel/sched/features.h | 5 +++++ + 1 file changed, 5 insertions(+) + +diff --git a/kernel/sched/features.h b/kernel/sched/features.h +index 85ae8488039c..68de18405857 100644 +--- a/kernel/sched/features.h ++++ b/kernel/sched/features.h +@@ -46,11 +46,16 @@ SCHED_FEAT(LB_BIAS, true) + */ + SCHED_FEAT(NONTASK_CAPACITY, true) + ++#ifdef CONFIG_PREEMPT_RT_FULL ++SCHED_FEAT(TTWU_QUEUE, false) ++#else ++ + /* + * Queue remote wakeups on the target CPU and process them + * using the scheduler IPI. Reduces rq->lock contention/bounces. + */ + SCHED_FEAT(TTWU_QUEUE, true) ++#endif + + /* + * When doing wakeups, attempt to limit superfluous scans of the LLC domain. +-- +2.36.1 + |