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=-8.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D49D3C004C9 for ; Tue, 7 May 2019 21:04:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A3389205C9 for ; Tue, 7 May 2019 21:04:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="KTfyAoLB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728462AbfEGVEr (ORCPT ); Tue, 7 May 2019 17:04:47 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:38994 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726686AbfEGVEr (ORCPT ); Tue, 7 May 2019 17:04:47 -0400 Received: by mail-pf1-f194.google.com with SMTP id z26so9284270pfg.6 for ; Tue, 07 May 2019 14:04:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=Tp9MHM6S82XiPQpC6c6jLekBkf9kgfqCZQyGw89KOqE=; b=KTfyAoLB21CgLn4vV+DeWm27Z0NxxbAZXzSaXHMVtSC6cam9l8ioBG5uvVhsSKhamD 5O8P15XSzgMcT/aYJ6UID2M634g4V0M18eMkOog2O/53+5MJUBFoNjUQ9F7KCvtIlc4F B7frY+UwvuCyqkixc99UccY4Q4r/WBFLetyaU1tp/0auaUSzitr5YJbs0NRr/EXsA/jO Qyum4xwKpBUibLnDJd56JqbnQhzMKlTw48Fm+bceoOk5CPJFQlg4L/CGlS/yDMrG3cxg d0npEcAiUhLIsWEerZF+tsXsVCqSY4NIlXXm2r0szlHmhPy19eJTu1TlNSwo9/sG4/Cs +ZSw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=Tp9MHM6S82XiPQpC6c6jLekBkf9kgfqCZQyGw89KOqE=; b=k2euQ5smjBg3KHZoMAZYCXkcKk8z+j+sM5actdwhzIW1ugsoGMvUTWEa0Ivbl9DtlW WAIAqkMR78p3mxGMpfX4cA+nlbUB7uScQI5Zo4da3H/odDaNAgrZ/b1aQYFkH3bMNq5k vDzk3n9fZBaf7wUT4Z52QWRCFqsHa6UrZFZbDkjmFpnNTVjFaMbGSI2XxaZnge2GlMw0 TVe+hjoTLBnJBL5GZNmIrVb2CH8t5FrWz5I3+i8E0QuwUR3y0Tt/LqyTwlA5MUU0AzeO 0pR3E8HzNBch/lbOwerqo+0FYgrORkw4RfcVIxZFmkSWglFgDqPHWtsR+WdeBvPCHZTT 4c2A== X-Gm-Message-State: APjAAAWQMFT1eoWbJw4X0fpzMbazX7KQDjja+0EpSVXH7hnjSBXYISZE NM/kTegjY+X51NivGd9JVWdDrWC6 X-Google-Smtp-Source: APXvYqzflAmUTQydzxJ4cjPRW0WIecf2bKx2yQBktISYk/b4xLlIZ0c6pxz/B7pjskqQcN+h0MZuiQ== X-Received: by 2002:a65:6496:: with SMTP id e22mr42445689pgv.249.1557263086677; Tue, 07 May 2019 14:04:46 -0700 (PDT) Received: from localhost ([2601:640:2:82fb:19d3:11c4:475e:3daa]) by smtp.gmail.com with ESMTPSA id u66sm5867753pfa.36.2019.05.07.14.04.45 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 07 May 2019 14:04:45 -0700 (PDT) Date: Tue, 7 May 2019 14:04:44 -0700 From: Yury Norov To: Aaron Tomlin , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton Cc: Yury Norov , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/slub: avoid double string traverse in kmem_cache_flags() Message-ID: <20190507210444.GB8935@yury-thinkpad> References: <20190501053111.7950-1-ynorov@marvell.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190501053111.7950-1-ynorov@marvell.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 30, 2019 at 10:31:11PM -0700, Yury Norov wrote: > If ',' is not found, kmem_cache_flags() calls strlen() to find the end > of line. We can do it in a single pass using strchrnul(). Ping? > Signed-off-by: Yury Norov > --- > mm/slub.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/mm/slub.c b/mm/slub.c > index 4922a0394757..85f90370a293 100644 > --- a/mm/slub.c > +++ b/mm/slub.c > @@ -1317,9 +1317,7 @@ slab_flags_t kmem_cache_flags(unsigned int object_size, > char *end, *glob; > size_t cmplen; > > - end = strchr(iter, ','); > - if (!end) > - end = iter + strlen(iter); > + end = strchrnul(iter, ','); > > glob = strnchr(iter, end - iter, '*'); > if (glob) > -- > 2.17.1