[tip:timers/nohz] sched/cputime: Drop local_irq_save/restore from irqtime_account_irq()

From: tip-bot for Rik van Riel
Date: Thu Jul 14 2016 - 06:39:46 EST


Commit-ID: 553bf6bbfd8a540c70aee28eb50e24caff456a03
Gitweb: http://git.kernel.org/tip/553bf6bbfd8a540c70aee28eb50e24caff456a03
Author: Rik van Riel <riel@xxxxxxxxxx>
AuthorDate: Wed, 13 Jul 2016 16:50:05 +0200
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Thu, 14 Jul 2016 10:42:35 +0200

sched/cputime: Drop local_irq_save/restore from irqtime_account_irq()

Paolo pointed out that irqs are already blocked when irqtime_account_irq()
is called. That means there is no reason to call local_irq_save/restore()
again.

Suggested-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Rik van Riel <riel@xxxxxxxxxx>
Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Reviewed-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Radim Krcmar <rkrcmar@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Wanpeng Li <wanpeng.li@xxxxxxxxxxx>
Link: http://lkml.kernel.org/r/1468421405-20056-6-git-send-email-fweisbec@xxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
kernel/sched/cputime.c | 4 ----
1 file changed, 4 deletions(-)

diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index 16a873c..ea0f6f3 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -49,15 +49,12 @@ DEFINE_PER_CPU(seqcount_t, irq_time_seq);
*/
void irqtime_account_irq(struct task_struct *curr)
{
- unsigned long flags;
s64 delta;
int cpu;

if (!sched_clock_irqtime)
return;

- local_irq_save(flags);
-
cpu = smp_processor_id();
delta = sched_clock_cpu(cpu) - __this_cpu_read(irq_start_time);
__this_cpu_add(irq_start_time, delta);
@@ -75,7 +72,6 @@ void irqtime_account_irq(struct task_struct *curr)
__this_cpu_add(cpu_softirq_time, delta);

irq_time_write_end();
- local_irq_restore(flags);
}
EXPORT_SYMBOL_GPL(irqtime_account_irq);