From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753088AbeC2Ll1 (ORCPT ); Thu, 29 Mar 2018 07:41:27 -0400 Received: from merlin.infradead.org ([205.233.59.134]:33992 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753017AbeC2LlZ (ORCPT ); Thu, 29 Mar 2018 07:41:25 -0400 Date: Thu, 29 Mar 2018 13:41:14 +0200 From: Peter Zijlstra To: Dominik Brodowski Cc: linux-kernel@vger.kernel.org, viro@ZenIV.linux.org.uk, torvalds@linux-foundation.org, arnd@arndb.de, linux-arch@vger.kernel.org, Ingo Molnar Subject: Re: [PATCH 043/109] sched: add do_sched_yield() helper; remove in-kernel call to sched_yield() Message-ID: <20180329114114.GQ4082@hirez.programming.kicks-ass.net> References: <20180329112426.23043-1-linux@dominikbrodowski.net> <20180329112426.23043-44-linux@dominikbrodowski.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180329112426.23043-44-linux@dominikbrodowski.net> User-Agent: Mutt/1.9.3 (2018-01-21) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Mar 29, 2018 at 01:23:20PM +0200, Dominik Brodowski wrote: > Using the sched-internal do_sched_yield() helper allows us to get rid of > the sched-internal call to the sys_sched_yield() syscall. > > This patch is part of a series which removes in-kernel calls to syscalls. > On this basis, the syscall entry path can be streamlined. For details, see > http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net > > Cc: Ingo Molnar Acked-by: Peter Zijlstra (Intel) > Signed-off-by: Dominik Brodowski > --- > kernel/sched/core.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index e7c535eee0a6..8de4919c889a 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -4892,7 +4892,7 @@ SYSCALL_DEFINE3(sched_getaffinity, pid_t, pid, unsigned int, len, > * > * Return: 0. > */ > -SYSCALL_DEFINE0(sched_yield) > +static void do_sched_yield(void) > { > struct rq_flags rf; > struct rq *rq; > @@ -4913,7 +4913,11 @@ SYSCALL_DEFINE0(sched_yield) > sched_preempt_enable_no_resched(); > > schedule(); > +} > > +SYSCALL_DEFINE0(sched_yield) > +{ > + do_sched_yield(); > return 0; > } > > @@ -4997,7 +5001,7 @@ EXPORT_SYMBOL(__cond_resched_softirq); > void __sched yield(void) > { > set_current_state(TASK_RUNNING); > - sys_sched_yield(); > + do_sched_yield(); > } > EXPORT_SYMBOL(yield); > > -- > 2.16.3 >