Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753464Ab3H1La3 (ORCPT ); Wed, 28 Aug 2013 07:30:29 -0400 Received: from mail9.hitachi.co.jp ([133.145.228.44]:37056 "EHLO mail9.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751936Ab3H1La2 (ORCPT ); Wed, 28 Aug 2013 07:30:28 -0400 X-AuditID: 85900ec0-d3b2cb9000001514-2e-521ddf527011 Message-ID: <521DDF49.1090301@hitachi.com> Date: Wed, 28 Aug 2013 20:30:17 +0900 From: Yoshihiro YUNOMAE User-Agent: Mozilla/5.0 (Windows NT 5.2; rv:13.0) Gecko/20120604 Thunderbird/13.0 MIME-Version: 1.0 To: Steven Rostedt Cc: Hidehiro Kawai , Masami Hiramatsu , linux-kernel@vger.kernel.org, yrl.pp-manager.tt@hitachi.com Subject: Re: Re: [RFC PATCH 08/11] trace-cmd: Apply the trace-msg protocol for communication between a server and clients References: <20130819094620.26597.79499.stgit@yunodevel> <20130819094639.26597.44449.stgit@yunodevel> <20130820135658.5a5d6e28@gandalf.local.home> <521AB469.40201@hitachi.com> <20130826111105.5d6504e0@gandalf.local.home> <521C7E1C.5060502@hitachi.com> <20130827090509.598591e8@gandalf.local.home> In-Reply-To: <20130827090509.598591e8@gandalf.local.home> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1499 Lines: 38 (2013/08/27 22:05), Steven Rostedt wrote: > On Tue, 27 Aug 2013 19:23:24 +0900 > Yoshihiro YUNOMAE wrote: > >> OK, let me check that. Even if the old server will receive "V2", the >> server will send port numbers instead of "V2" due to the old protocol. >> In that time, the new client will disconnect from the old server and >> the restarts with the old protocol. Is it OK? > > Yep, that's exactly what I meant ;-) I tried to implement the feature, but I found that sending just "V2" from the new client is inappropriate. This is because the old server doesn't respond to the client before receiving cpu numbers, page size, and options. So, when the new client sends the first message, it should send "V2\0\00\0", I think. If so, the old server will understand the message as cpus=0, pagesize=, options=0, and then it will send port numbers(actually \0). Note if is zero, the old server will die. Can I implement the first message of the new client as "V2\0\00\0"? Thanks, Yoshihiro YUNOMAE -- Yoshihiro YUNOMAE Software Platform Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: yoshihiro.yunomae.ez@hitachi.com -- 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/