From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757097AbcAJLxd (ORCPT ); Sun, 10 Jan 2016 06:53:33 -0500 Received: from mx1.redhat.com ([209.132.183.28]:47880 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757058AbcAJLxb (ORCPT ); Sun, 10 Jan 2016 06:53:31 -0500 Date: Sun, 10 Jan 2016 13:53:26 +0200 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: Peter Zijlstra , Martin Schwidefsky , Heiko Carstens , Ingo Molnar , Arnd Bergmann , Davidlohr Bueso , Andrey Konovalov , Christian Borntraeger , linux-s390@vger.kernel.org Subject: [PATCH] s390: more efficient smp barriers Message-ID: <1452426771-27112-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Mutt-Fcc: =sent Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As per: lkml.kernel.org/r/20150921112252.3c2937e1@mschwide atomics imply a barrier on s390, so s390 should change smp_mb__before_atomic and smp_mb__after_atomic to barrier() instead of smp_mb() and hence should not use the generic versions. Suggested-by: Peter Zijlstra Suggested-by: Martin Schwidefsky Signed-off-by: Michael S. Tsirkin --- This is on top of arch barrier cleanup patchset, will be included in v3 of that patchset. arch/s390/include/asm/barrier.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/s390/include/asm/barrier.h b/arch/s390/include/asm/barrier.h index 4d26fa4..5c8db3c 100644 --- a/arch/s390/include/asm/barrier.h +++ b/arch/s390/include/asm/barrier.h @@ -45,6 +45,9 @@ do { \ ___p1; \ }) +#define __smp_mb__before_atomic() barrier() +#define __smp_mb__after_atomic() barrier() + #include #endif /* __ASM_BARRIER_H */ -- MST