From mboxrd@z Thu Jan 1 00:00:00 1970 From: Martin Schwidefsky Subject: Re: [PATCH] bitmap_equal memcmp optimization for s390 Date: Thu, 9 Jun 2016 16:45:32 +0200 Message-ID: <20160609164532.23f05026@mschwide> References: <201606070837.u578Y1R5037289@mx0a-001b2d01.pphosted.com> <28415.1465482407@warthog.procyon.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <28415.1465482407@warthog.procyon.org.uk> Sender: linux-kernel-owner@vger.kernel.org To: David Howells Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Benjamin Herrenschmidt , "David S. Miller" List-Id: linux-arch.vger.kernel.org On Thu, 09 Jun 2016 15:26:47 +0100 David Howells wrote: > 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__. Yes indeed. How strange to define __HAVE_ARCH_xxx for user space only. -- blue skies, Martin. "Reality continues to ruin my life." - Calvin. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:12370 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932069AbcFIOqP (ORCPT ); Thu, 9 Jun 2016 10:46:15 -0400 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u59Ehdks114639 for ; Thu, 9 Jun 2016 10:46:14 -0400 Received: from e06smtp14.uk.ibm.com (e06smtp14.uk.ibm.com [195.75.94.110]) by mx0b-001b2d01.pphosted.com with ESMTP id 23e9m4p0sq-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 09 Jun 2016 10:46:13 -0400 Received: from localhost by e06smtp14.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 9 Jun 2016 15:46:12 +0100 Date: Thu, 9 Jun 2016 16:45:32 +0200 From: Martin Schwidefsky Subject: Re: [PATCH] bitmap_equal memcmp optimization for s390 In-Reply-To: <28415.1465482407@warthog.procyon.org.uk> References: <201606070837.u578Y1R5037289@mx0a-001b2d01.pphosted.com> <28415.1465482407@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Message-ID: <20160609164532.23f05026@mschwide> Sender: linux-arch-owner@vger.kernel.org List-ID: To: David Howells Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Benjamin Herrenschmidt , "David S. Miller" Message-ID: <20160609144532.CQhrcQq0ctjdrPgC2rb7JrBT9_srTN17l7BZajURxt0@z> On Thu, 09 Jun 2016 15:26:47 +0100 David Howells wrote: > 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__. Yes indeed. How strange to define __HAVE_ARCH_xxx for user space only. -- blue skies, Martin. "Reality continues to ruin my life." - Calvin.