Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753355AbZDTHTU (ORCPT ); Mon, 20 Apr 2009 03:19:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751905AbZDTHTG (ORCPT ); Mon, 20 Apr 2009 03:19:06 -0400 Received: from ti-out-0910.google.com ([209.85.142.184]:64128 "EHLO ti-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751562AbZDTHTD (ORCPT ); Mon, 20 Apr 2009 03:19:03 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:reply-to:to:cc:in-reply-to:references:content-type :organization:date:message-id:mime-version:x-mailer :content-transfer-encoding; b=hEeoNltDuyOZb8GYEtd1Ya5Dii1F1Nq9vk0MBMvsu8AggTvB6W2mW6H/ikvkkLEQ5K 4L8XUmP6k60W8crtGkESLLl/LlN+1YBA8jWYiA/06NBV6Oh/6xSj4ggIDsriR3s2IzsH TtHf81LjPCxbgvtBLGMny+hqJNcUTwEDJdjlY= Subject: Re: "RT_PREEMPT for loongson" is updated to patch-2.6.29.1-rt8 From: Wu Zhangjin Reply-To: wuzhangjin@gmail.com To: Zhang Le Cc: linux-kernel@vger.kernel.org, Nicholas Mc Guire , Ingo Molnar , Thomas Gleixner , zhangfx@lemote.com, loongson-dev@googlegroups.com, yanh@lemote.com, Ralf Baechle , linux-mips@linux-mips.org, linux-rt-users@vger.kernel.org In-Reply-To: <20090420050419.GA22520@adriano.hkcable.com.hk> References: <1240193547.25532.52.camel@falcon> <20090420050419.GA22520@adriano.hkcable.com.hk> Content-Type: text/plain Organization: DSLab, Lanzhou University, China Date: Mon, 20 Apr 2009 15:18:46 +0800 Message-Id: <1240211926.8884.27.camel@falcon> Mime-Version: 1.0 X-Mailer: Evolution 2.24.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1662 Lines: 47 On Mon, 2009-04-20 at 13:04 +0800, Zhang Le wrote: > Hi, Zhangjin, > > Ralf told me he has a ftrace implementation too. > > 11:47 < Ralf> r0bertz: ftrace looks nice but not yet mergable yet. > 11:47 < Ralf> r0bertz: I also have my own ftrace implementation which in some > parts is better, in some is worse. > 11:47 < Ralf> r0bertz: So this is going to be quite a job. > > So I think you can talk to Ralf about how to get this merged, :) > to Zhangle, thx very much for your info :-) hope Ralf can reply this E-mail and pull the source code from my git tree: git://dev.lemote.com/rt4ls.git to Ralf, I have divided ftrace to several commits in the above git tree, hope you can check it, thx :-) in addition to the static/dynamic/graph function tracer & system call tracer implementation, a mips specific ring_buffer_time_stamp (kernel/trace/ring_buffer.c) is also implemented to get 1us precision time, this is very important to make ftrace available in mips, otherwise, we can only get 1ms precision time for the original ring_buffer_time_stamp is based on sched_clock(jiffies based). perhaps we can implement a more precise sched_clock directly, just as x86 does(native_sched_clock, tsc based), but in mips, there is only a 32bit timer count which will quickly overflow, so it will need an extra overflow protection, which may influence the other parts of the kernel. best regards, Wu Zhangjin -- 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/