Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753063AbZKSVIF (ORCPT ); Thu, 19 Nov 2009 16:08:05 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752380AbZKSVIE (ORCPT ); Thu, 19 Nov 2009 16:08:04 -0500 Received: from mx1.redhat.com ([209.132.183.28]:13056 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752284AbZKSVID (ORCPT ); Thu, 19 Nov 2009 16:08:03 -0500 Message-ID: <4B05B32C.9020503@redhat.com> Date: Thu, 19 Nov 2009 14:05:48 -0700 From: Jeff Law User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.4pre) Gecko/20091014 Fedora/3.0-2.8.b4.fc11 Thunderbird/3.0b4 MIME-Version: 1.0 To: "H. Peter Anvin" CC: rostedt@goodmis.org, David Daney , Linus Torvalds , Andrew Haley , Richard Guenther , Thomas Gleixner , Ingo Molnar , LKML , Andrew Morton , Heiko Carstens , feng.tang@intel.com, Fr??d??ric Weisbecker , Peter Zijlstra , jakub@redhat.com, gcc@gcc.gnu.org Subject: Re: BUG: GCC-4.4.x changes the function frame on some functions References: <20091119072040.GA23579@elte.hu> <1258653562.22249.682.camel@gandalf.stny.rr.com> <84fc9c000911191003t244eb864o3d5b355ab5485f@mail.gmail.com> <4B058CCD.8050605@redhat.com> <4B05982B.6060200@caviumnetworks.com> <1258658886.22249.874.camel@gandalf.stny.rr.com> <4B05A16D.1050807@zytor.com> In-Reply-To: <4B05A16D.1050807@zytor.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 806 Lines: 18 On 11/19/09 12:50, H. Peter Anvin wrote: > > Calling the profiler immediately at the entry point is clearly the more > sane option. It means the ABI is well-defined, stable, and independent > of what the actual function contents are. It means that ABI isn't the > normal C ABI (the __fentry__ function would have to preserve all > registers), but that's fine... > Note there are targets (even some old x86 variants) that required the profiling calls to occur after the prologue. Unfortunately, nobody documented *why* that was the case. Sigh. Jeff -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/