From a4f61cc03e443647211a5ae0ab8f8cda2e9e1043 Mon Sep 17 00:00:00 2001 From: Christoph Lameter <cl@gentwo.org> Date: Wed, 7 Aug 2013 15:38:24 +0000 Subject: [PATCH] sched/cputime: Use this_cpu_add() in task_group_account_field() Use of a this_cpu() operation reduces the number of instructions used for accounting (account_user_time()) and frees up some registers. This is in the scheduler tick hotpath. Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/00000140596dd165-338ff7f5-893b-4fec-b251-aaac5557239e-000000@email.amazonses.com Signed-off-by: Ingo Molnar <mingo@kernel.org> --- kernel/sched/cputime.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c index a7959e05a9d5..e89ccefef278 100644 --- a/kernel/sched/cputime.c +++ b/kernel/sched/cputime.c @@ -121,7 +121,7 @@ static inline void task_group_account_field(struct task_struct *p, int index, * is the only cgroup, then nothing else should be necessary. * */ - __get_cpu_var(kernel_cpustat).cpustat[index] += tmp; + __this_cpu_add(kernel_cpustat.cpustat[index], tmp); cpuacct_account_field(p, index, tmp); }