From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752807AbbCJMmZ (ORCPT ); Tue, 10 Mar 2015 08:42:25 -0400 Received: from mail-qg0-f47.google.com ([209.85.192.47]:44793 "EHLO mail-qg0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751678AbbCJMmY (ORCPT ); Tue, 10 Mar 2015 08:42:24 -0400 Date: Tue, 10 Mar 2015 08:42:20 -0400 From: Tejun Heo To: Rasmus Villemoes Cc: Joe Perches , linux-kernel@vger.kernel.org, "Peter Zijlstra (Intel)" , Andrew Morton Subject: Re: [RFC] lib/vsprintf.c: Even faster decimal conversion Message-ID: <20150310124220.GA28730@htj.duckdns.org> References: <1424476281-26873-1-git-send-email-linux@rasmusvillemoes.dk> <87r3t3eafm.fsf@rasmusvillemoes.dk> <1425571413.31859.1.camel@perches.com> <20150305161051.GE23912@htj.duckdns.org> <87egp384m0.fsf@rasmusvillemoes.dk> <87zj7l6sdo.fsf@rasmusvillemoes.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87zj7l6sdo.fsf@rasmusvillemoes.dk> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Tue, Mar 10, 2015 at 11:47:47AM +0100, Rasmus Villemoes wrote: > I can't explain why num_to_str apparently becomes slightly slower (the > patch essentially didn't touch it), but the put_dec_ helpers in any case > make up for that. Unrelated code changes affecting performance in seemingly random way isn't too uncommon. A lot of it arises from cacheline behaviors. The effect is sometimes surprisingly big. Generally looks pretty good to me. Andrew, can you please pick this patch up? Thanks. -- tejun