From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by aws-us-west-2-korg-lkml-1.web.codeaurora.org (Postfix) with ESMTP id B3DB2C5CFF1 for ; Tue, 12 Jun 2018 17:02:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4F6A6208B1 for ; Tue, 12 Jun 2018 17:02:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4F6A6208B1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=c-s.fr Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935178AbeFLRCM (ORCPT ); Tue, 12 Jun 2018 13:02:12 -0400 Received: from pegase1.c-s.fr ([93.17.236.30]:35037 "EHLO pegase1.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933685AbeFLRCC (ORCPT ); Tue, 12 Jun 2018 13:02:02 -0400 Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 414x4j2svqz9ttFY; Tue, 12 Jun 2018 19:01:57 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id JJT7Sv4aK7K2; Tue, 12 Jun 2018 19:01:57 +0200 (CEST) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 414x4j2LPzz9ttFW; Tue, 12 Jun 2018 19:01:57 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id AB1378B95F; Tue, 12 Jun 2018 19:02:00 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id GX9O-VVjFo9g; Tue, 12 Jun 2018 19:02:00 +0200 (CEST) Received: from PO15451 (unknown [192.168.232.3]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 1481F8B940; Tue, 12 Jun 2018 19:02:00 +0200 (CEST) Subject: Re: [PATCH v6 3/4] powerpc/lib: implement strlen() in assembly To: Segher Boessenkool Cc: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , wei.guo.simon@gmail.com, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org References: <85de16f5629ac9f4a815230cced361908758b53a.1528791416.git.christophe.leroy@c-s.fr> <8b89f2e21f7e3a865105eeeeda509243db393454.1528791416.git.christophe.leroy@c-s.fr> <20180612145315.GJ27520@gate.crashing.org> From: Christophe LEROY Message-ID: Date: Tue, 12 Jun 2018 19:01:59 +0200 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <20180612145315.GJ27520@gate.crashing.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: fr Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le 12/06/2018 à 16:53, Segher Boessenkool a écrit : > On Tue, Jun 12, 2018 at 09:14:53AM +0000, Christophe Leroy wrote: >> --- >> Not tested on PPC64. > > It won't be acceptable until that happens. It also is likely quite bad > performance on all 64-bit CPUs from the last fifteen years or so. Or you > did nothing to prove otherwise, at least. Will it be as bad as the generic implementation which does it byte per byte ? I don't have any 64 bits target, can someone test it using the test app I have added in selftests ? Or should I just leave it as is for 64 bits and just do the implementation for 32 bits until someone wants to try and do it for PPC64 ? Christophe > >> + * Algorigthm: > > Typo. > > > Segher >