From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 15152 invoked by alias); 19 Oct 2009 08:17:36 -0000 Received: (qmail 15124 invoked by uid 9687); 19 Oct 2009 08:17:35 -0000 Date: Mon, 19 Oct 2009 08:17:00 -0000 Message-ID: <20091019081734.15111.qmail@sourceware.org> From: srikar@sourceware.org To: systemtap-cvs@sourceware.org Subject: [SCM] systemtap: system-wide probe/trace tool branch, master, updated. release-1.0-114-g720bbfc X-Git-Refname: refs/heads/master X-Git-Reftype: branch X-Git-Oldrev: 3c2341daf979fc38fc534ae91e00594a525962e0 X-Git-Newrev: 720bbfc68d9e7dfd8c37587c6a61da75d6aab4fa Mailing-List: contact systemtap-cvs-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: systemtap-cvs-owner@sourceware.org List-Archive: Reply-To: systemtap@sourceware.org X-SW-Source: 2009-q4/txt/msg00049.txt.bz2 This is an automated email from the git hooks/post-receive script. It was generated because a ref change was pushed to the repository containing the project "systemtap: system-wide probe/trace tool". The branch, master has been updated via 720bbfc68d9e7dfd8c37587c6a61da75d6aab4fa (commit) from 3c2341daf979fc38fc534ae91e00594a525962e0 (commit) Those revisions listed above that are new to this repository have not appeared on any other notification email; so we list those revisions in full, below. - Log ----------------------------------------------------------------- commit 720bbfc68d9e7dfd8c37587c6a61da75d6aab4fa Author: Srikar Dronamraju Date: Mon Oct 19 13:44:21 2009 +0530 Avoid lockdep warnings. uprobe_fork_uproc() runs with parent_uproc->rwsem locked. However uprobe_mk_process() that gets called within uprobe_fork_uproc() also locks child_uproc->rwsem after initializing it. Lockdep report confuses this to acquiring a lock that already has been acquired and suggests using sub-classes. The alternatives we have are: 1. use classes level to distinguish different uproc structures. 2. unlock parent_uproc->rwsem before we call uprobe_fork_uproc(). 3. dont try locking child_uproc->rwsem; since we are protected by uproc_mutex as well as parent_uproc->rwsem; We use the last approach. Signed-off-by: Srikar Dronamraju --- ----------------------------------------------------------------------- Summary of changes: runtime/uprobes/uprobes.c | 24 +++++++++++++++++------- runtime/uprobes2/uprobes.c | 24 +++++++++++++++++------- 2 files changed, 34 insertions(+), 14 deletions(-) hooks/post-receive -- systemtap: system-wide probe/trace tool