From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932232AbcFIO0w (ORCPT ); Thu, 9 Jun 2016 10:26:52 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47540 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932069AbcFIO0u (ORCPT ); Thu, 9 Jun 2016 10:26:50 -0400 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <201606070837.u578Y1R5037289@mx0a-001b2d01.pphosted.com> References: <201606070837.u578Y1R5037289@mx0a-001b2d01.pphosted.com> To: Martin Schwidefsky Cc: dhowells@redhat.com, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Benjamin Herrenschmidt , "David S. Miller" Subject: Re: [PATCH] bitmap_equal memcmp optimization for s390 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <28414.1465482407.1@warthog.procyon.org.uk> Date: Thu, 09 Jun 2016 15:26:47 +0100 Message-ID: <28415.1465482407@warthog.procyon.org.uk> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Thu, 09 Jun 2016 14:26:50 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Martin Schwidefsky wrote: > I hesitate to put another CONFIG_S390 into common code, alternatively > __HAVE_ARCH_MEMCMP could be used. There are 7 architectures with the > define: arc, arm64, blackfin, frv, powerpc, s390 and sparc. > Of those I guess only powerpc, s390 and sparc will have configs with > (NR_CPUS > BITS_PER_LONG). For (NR_CPUS <= BITS_PER_LONG) the xor > optimization is used. FRV doesn't have __HAVE_ARCH_MEMCMP for __KERNEL__. David