From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751593AbcHGVWh (ORCPT ); Sun, 7 Aug 2016 17:22:37 -0400 Received: from smtprelay0171.hostedemail.com ([216.40.44.171]:43206 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750815AbcHGVWg (ORCPT ); Sun, 7 Aug 2016 17:22:36 -0400 X-Session-Marker: 6A6F6540706572636865732E636F6D X-Spam-Summary: 2,0,0,,d41d8cd98f00b204,joe@perches.com,:::::::::,RULES_HIT:41:355:379:541:599:973:988:989:1260:1277:1311:1313:1314:1345:1359:1373:1437:1515:1516:1518:1534:1539:1593:1594:1711:1730:1747:1777:1792:2393:2559:2562:2691:2828:3138:3139:3140:3141:3142:3352:3622:3865:3866:3867:3868:3870:3871:3872:3873:3874:4250:4321:5007:6119:7903:8603:10004:10400:10848:11232:11658:11914:12517:12519:12740:13069:13311:13357:13439:14659:14721:21080:30012:30046:30054:30091,0,RBL:none,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fn,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:6,LUA_SUMMARY:none X-HE-Tag: star77_8ab33d35f3e31 X-Filterd-Recvd-Size: 1731 Message-ID: <1470604951.28648.44.camel@perches.com> Subject: Re: [PATCH] proc: faster /proc/*/status From: Joe Perches To: Andi Kleen Cc: Alexey Dobriyan , akpm@linux-foundation.org, linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk Date: Sun, 07 Aug 2016 14:22:31 -0700 In-Reply-To: <20160807174402.GY5871@two.firstfloor.org> References: <20160806125608.GB1187@p183.telecom.by> <87ziop46b8.fsf@tassilo.jf.intel.com> <20160807085322.GB1871@p183.telecom.by> <20160807165947.GX5871@two.firstfloor.org> <1470591565.28648.40.camel@perches.com> <20160807174402.GY5871@two.firstfloor.org> Content-Type: text/plain; charset="ISO-8859-1" X-Mailer: Evolution 3.18.5.2-0ubuntu3 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2016-08-07 at 10:44 -0700, Andi Kleen wrote: > > > > It is so bloated that gcc needs to be asked to not screw up with stack > > > > size. > > > What happens when you drop all the noinlines for this? I assume > > > this would alread make it faster. And now that we have bigger > > > stacks we can likely tolerate it. > > %pV recurses through these code paths. > > I believe the maximum current recursion depth is 3. > I assume 2 max would sufficient for all users in kernel. > > And perhaps it would be better to get rid of "features" like this, > and instead focus on more common cases. It'd be a dubious trade-off in my opinion. Overall code size has been reduced by hundreds of KB by using %pV.