[PATCH] sched/core: Remove double update_max_interval() call on CPU startup

[PATCH] sched/core: Remove double update_max_interval() call on CPU startup

[Valentin Schneider]

update_max_interval() is called in both CPUHP_AP_SCHED_STARTING's startup
and teardown callbacks, but it turns out it's also called at the end of
the startup callback of CPUHP_AP_ACTIVE (which is further down the
startup sequence).

There's no point in repeating this interval update in the startup sequence
since the CPU will remain online until it goes down the teardown path.

Remove the redundant call in sched_cpu_activate() (CPUHP_AP_ACTIVE).

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
---
 kernel/sched/core.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 87b84a726db4..6b94e71f659e 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6418,9 +6418,6 @@ int sched_cpu_activate(unsigned int cpu)
 	}
 	rq_unlock_irqrestore(rq, &rf);
 
-	update_max_interval();
-
 	return 0;
 }
 
--
2.22.0

[tip: sched/urgent] sched/core: Remove double update_max_interval() call on CPU startup

[tip-bot2 for Valentin Schneider]

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

Commit-ID:     9fc41acc89e58262c917b4be89ef00a87485804f
Gitweb:        https://git.kernel.org/tip/9fc41acc89e58262c917b4be89ef00a87485804f
Author:        Valentin Schneider <valentin.schneider@arm.com>
AuthorDate:    Mon, 23 Sep 2019 10:30:17 +01:00
Committer:     Ingo Molnar <mingo@kernel.org>
CommitterDate: Wed, 25 Sep 2019 17:42:32 +02:00

sched/core: Remove double update_max_interval() call on CPU startup

update_max_interval() is called in both CPUHP_AP_SCHED_STARTING's startup
and teardown callbacks, but it turns out it's also called at the end of
the startup callback of CPUHP_AP_ACTIVE (which is further down the
startup sequence).

There's no point in repeating this interval update in the startup sequence
since the CPU will remain online until it goes down the teardown path.

Remove the redundant call in sched_cpu_activate() (CPUHP_AP_ACTIVE).

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: juri.lelli@redhat.com
Cc: vincent.guittot@linaro.org
Link: https://lkml.kernel.org/r/20190923093017.11755-1-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 kernel/sched/core.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 00ef44c..1b61cf4 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6425,8 +6425,6 @@ int sched_cpu_activate(unsigned int cpu)
 	}
 	rq_unlock_irqrestore(rq, &rf);
 
-	update_max_interval();
-
 	return 0;
 }