From 738d2be4301007f054541c5c4bf7fb6a361c9b3a Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 16 Dec 2009 18:04:42 +0100 Subject: [PATCH] sched: Simplify set_task_cpu() Rearrange code a bit now that its a simpler function. Signed-off-by: Peter Zijlstra Cc: Mike Galbraith LKML-Reference: <20091216170518.269101883@chello.nl> Signed-off-by: Ingo Molnar --- kernel/sched.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/kernel/sched.c b/kernel/sched.c index f92ce63edfff..8a2bfd37ab4f 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -2034,11 +2034,8 @@ task_hot(struct task_struct *p, u64 now, struct sched_domain *sd) return delta < (s64)sysctl_sched_migration_cost; } - void set_task_cpu(struct task_struct *p, unsigned int new_cpu) { - int old_cpu = task_cpu(p); - #ifdef CONFIG_SCHED_DEBUG /* * We should never call set_task_cpu() on a blocked task, @@ -2049,11 +2046,11 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu) trace_sched_migrate_task(p, new_cpu); - if (old_cpu != new_cpu) { - p->se.nr_migrations++; - perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS, - 1, 1, NULL, 0); - } + if (task_cpu(p) == new_cpu) + return; + + p->se.nr_migrations++; + perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS, 1, 1, NULL, 0); __set_task_cpu(p, new_cpu); }