Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935217AbdCVOSp (ORCPT ); Wed, 22 Mar 2017 10:18:45 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42854 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935203AbdCVOS1 (ORCPT ); Wed, 22 Mar 2017 10:18:27 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 7989264A6E Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=jpoimboe@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 7989264A6E Date: Wed, 22 Mar 2017 09:18:23 -0500 From: Josh Poimboeuf To: Peter Zijlstra Cc: mingo@kernel.org, tglx@linutronix.de, hpa@zytor.com, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, arjan@linux.intel.com, bp@alien8.de, richard.weinberger@gmail.com Subject: Re: [PATCH 1/5] x86: Implement __WARN using UD0 Message-ID: <20170322141823.2ilzsmfeghe3ra4j@treble> References: <20170317211918.393791494@infradead.org> <20170317212350.828368979@infradead.org> <20170321140340.urru2lmjko6txwl5@treble> <20170322084706.GV5680@worktop> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20170322084706.GV5680@worktop> User-Agent: Mutt/1.6.0.1 (2016-04-01) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Wed, 22 Mar 2017 14:18:27 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1253 Lines: 36 On Wed, Mar 22, 2017 at 09:47:06AM +0100, Peter Zijlstra wrote: > > A little like so then. > > --- > Subject: x86: Implement __WARN using UD0 > From: Peter Zijlstra > Date: Thu Feb 2 14:43:51 CET 2017 > > By using "UD0" for WARNs we remove the function call and its possible > __FILE__ and __LINE__ immediate arguments from the instruction stream. > > Total image size will not change much, what we win in the instruction > stream we'll loose because of the __bug_table entries. Still, saves on > I$ footprint and the total image size does go down a bit. > > text data bss dec hex filename > 10702123 4530992 843776 16076891 f5505b defconfig-build/vmlinux.0 > 10682460 4530992 843776 16057228 f5038c defconfig-build/vmlinux.1 > > (um didn't seem to use GENERIC_BUG at all, so remove it) > > Cc: Linus Torvalds > Cc: Richard Weinberger > Cc: Arjan van de Ven > Cc: Borislav Petkov > Cc: Josh Poimboeuf > > Signed-off-by: Peter Zijlstra (Intel) Looks good, thanks! Reviewed-by: Josh Poimboeuf -- Josh