[PATCH 5/5] time: Drop local_irq_save/restore from irqtime_account_irq

Frederic Weisbecker
2016-07-13T14:51:08Z

From: Rik van Riel <riel@redhat.com>

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@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
---
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);

--
2.7.0