From owner-freebsd-current@FreeBSD.ORG Fri Mar 14 01:56:36 2014 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 57F3660C; Fri, 14 Mar 2014 01:56:36 +0000 (UTC) Received: from mail-yk0-x22e.google.com (mail-yk0-x22e.google.com [IPv6:2607:f8b0:4002:c07::22e]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id E1A07B8F; Fri, 14 Mar 2014 01:56:35 +0000 (UTC) Received: by mail-yk0-f174.google.com with SMTP id 20so5052142yks.5 for ; Thu, 13 Mar 2014 18:56:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=mOyJeoQSRL2cLTFAagwnxiN5QvdYDTx5WYqW8hgjRec=; b=VTQiWDBQIOmRQBvzebY3WDeoz9hesnyfsVoEl1bHMFDhWcw7ao14yOrpr6btfkXoMb 3bOZweQkaeR6Vnk/xWCKbbP0oL/M/MIgNxf49CZaTi0lNBopQMkk/ak90oGwBfyf2gKZ d/fbbEmDzavu3ueTj5as2ypQC7SO+iVeTBglDN6LKer5d9fpTOn8g88AMfO11MB/o8My LMv0KZ5gBVhP9PFZ0fsAy7gxwlrO1j9eMz5YGIEKZg/zuzCACn7JVxyK0atJ/zRFlTUK Ua+rwNBtShPy24sYS8OKu+2z5qP9nMVsvpBMTrJLVYXpRZmgljaNnXEYY3dM6jbo/RPH +2oQ== MIME-Version: 1.0 X-Received: by 10.236.51.71 with SMTP id a47mr7063766yhc.100.1394762195178; Thu, 13 Mar 2014 18:56:35 -0700 (PDT) Received: by 10.170.66.204 with HTTP; Thu, 13 Mar 2014 18:56:35 -0700 (PDT) In-Reply-To: References: Date: Thu, 13 Mar 2014 21:56:35 -0400 Message-ID: Subject: Re: FreeBSD GSOC proposal in 2014 From: yan cui To: freebsd-hackers@freebsd.org, freebsd-current@freebsd.org, soc-status@freebsd.org, jeff@freebsd.org Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.17 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 14 Mar 2014 01:56:36 -0000 Hi all, I write this mail to make my question clear. I know witness can be used to detect wrong lock order in the kernel. However, can it be used to do lock profiling (what I mean is to report the information such as which locks are most contended and print some related statistics such as calling graph, etc)? In other words, is it enough to finish the task by porting witness to the pthread library? Thanks, Yan 2014-03-13 19:19 GMT-04:00 yan cui : > Hi all, > > I have downloaded the newest FreeBSD-release kernel and scanned some > codes. > Wonder to know whether the lock order verification and lock profiling tool > mentioned in > the GSoC idea list is witness? Are there any other tools that needs to > look at in the FreeBSD kernel? > > Thanks, Yan > > > 2014-03-09 15:46 GMT-04:00 yan cui : > > Hi All, >> >> I am a student in Columbia University (Yan Cui), and want to join >> the FreeBSD GSOC 2014. After scanned the idea list posted online, I think I >> am interested in >> the idea titled "user space pthread mutex lock contention profiling and >> lock order verification tools". I have several year experiences in kernel >> and user locking and believe I can complete the task in time. Currently, I >> wonder to know, before submitting an application on GSOC home page, do I >> need to submit some documents in the community (to review?) >> >> Best Wishes! >> Yan >> >> -- >> Think big; Dream impossible; Make it happen. >> > > > > -- > Think big; Dream impossible; Make it happen. > -- Think big; Dream impossible; Make it happen.