On Wed, Feb 17, 2016 at 09:31:09AM +0100, Ingo Molnar wrote: > > * Byungchul Park <[email protected]> wrote: > > > Is there any reason keeping this statement on the code? > > > > -----8<----- > > From d8a387efb8199b69b6464970d6f9fc57cbcf0ab0 Mon Sep 17 00:00:00 2001 > > From: Byungchul Park <[email protected]> > > Date: Thu, 11 Feb 2016 11:50:53 +0900 > > Subject: [PATCH] sched: remove an unnecessary memory access, rq->cpu in > > __schedule() > > > > Remove an unnecessary assignment of variable not used any more. > > > > Signed-off-by: Byungchul Park <[email protected]> > > --- > > kernel/sched/core.c | 1 - > > 1 file changed, 1 deletion(-) > > > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > > index 1315cec..501f5d9 100644 > > --- a/kernel/sched/core.c > > +++ b/kernel/sched/core.c > > @@ -3193,7 +3193,6 @@ static void __sched notrace __schedule(bool preempt) > > > > trace_sched_switch(preempt, prev, next); > > rq = context_switch(rq, prev, next); /* unlocks the rq */ > > - cpu = cpu_of(rq); > > } else { > > lockdep_unpin_lock(&rq->lock); > > raw_spin_unlock_irq(&rq->lock); > > There's no memory access that I can see - GCC will optimize it out.
Yes, gcc will do it. So I expect no performance effect. > > Having said that, it is a dead statement so can be removed. I fixed the title > accordingly. Thank you. > > Thanks, > > Ingo
