From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932198AbZHDNfa (ORCPT ); Tue, 4 Aug 2009 09:35:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755537AbZHDNfa (ORCPT ); Tue, 4 Aug 2009 09:35:30 -0400 Received: from tomts16.bellnexxia.net ([209.226.175.4]:49993 "EHLO tomts16-srv.bellnexxia.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754305AbZHDNf3 (ORCPT ); Tue, 4 Aug 2009 09:35:29 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AuEEAHrUd0pMQWXi/2dsb2JhbACBUtMlhBgFgUo Date: Tue, 4 Aug 2009 09:35:15 -0400 From: Mathieu Desnoyers To: Giuseppe CAVALLARO Cc: ltt-dev@lists.casi.polymtl.ca, Matt Fleming , Paul Mundt , linux-kernel@vger.kernel.org, Ingo Molnar , rostedt@goodmis.org Subject: sh: Add ftrace syscall tracing support (was: Re: [ltt-dev] [PATCH] sh: added LTT_DUMP_TABLES support) Message-ID: <20090804133515.GB23807@Krystal> References: <1249040606-15402-1-git-send-email-peppe.cavallaro@st.com> <20090731155048.GD8847@Krystal> <4A77F585.2070508@st.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline In-Reply-To: <4A77F585.2070508@st.com> X-Editor: vi X-Info: http://krystal.dyndns.org:8080 X-Operating-System: Linux/2.6.21.3-grsec (i686) X-Uptime: 09:25:34 up 157 days, 9:51, 3 users, load average: 0.62, 1.03, 1.07 User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Giuseppe CAVALLARO (peppe.cavallaro@st.com) wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Hi Mathieu, > > Mathieu Desnoyers wrote: > > So now we only need to fix entry-common.S to get everything working. > > I've just noticed that this has been already done: > http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Flethal%2Fsh-2.6.git;a=commitdiff_plain;h=c652d780c9cf7f860141de232b37160fe013feca;hp=c1340c053be7a43d837a3acb352d5008be865a55 > I think it will be necessary to to re-add the _TIF_KERNEL_TRACE against > this modifications, only. > Hrm, I don't like the approach taken there. It extends the bitmasks for _TIF_WORK_SYSCALL_MASK and _TIF_ALLWORK_MASK beyond 8 bits, and adds a & 0xff in the assembly whenever needed. This begs for a bug to be introduced. If we need something like that on SH, we should probably declare a 8-bit only bitmask for those assembly sites which does not need the FTRACE_SYSCALL thread flag, and another mask for sites which need to test the 2 bytes. I would also consider other instructions than 2 consecutive "tst" to extend test with a 2 bytes mask. Something like loading an integer in a register and testing with the register rather than doing 2 immediate value tests. Mathieu > Regards, > Peppe > > > > > Mathieu > > > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.4.9 (GNU/Linux) > Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org > > iEYEARECAAYFAkp39YMACgkQ2Xo3j31MSSJWmQCeJfvmg3cUHsGGy5QNdRcOJbO9 > C1AAnR6gAuKZhaRt4+4UWiWDGucgD2DJ > =9cBd > -----END PGP SIGNATURE----- > -- Mathieu Desnoyers OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68