From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=51987 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PgDHR-0008Dy-O9 for qemu-devel@nongnu.org; Fri, 21 Jan 2011 04:27:42 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PgDHQ-0007Oa-3y for qemu-devel@nongnu.org; Fri, 21 Jan 2011 04:27:41 -0500 Received: from mtagate2.uk.ibm.com ([194.196.100.162]:35535) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PgDHP-0007IV-Mx for qemu-devel@nongnu.org; Fri, 21 Jan 2011 04:27:40 -0500 Received: from d06nrmr1307.portsmouth.uk.ibm.com (d06nrmr1307.portsmouth.uk.ibm.com [9.149.38.129]) by mtagate2.uk.ibm.com (8.13.1/8.13.1) with ESMTP id p0L9R492012852 for ; Fri, 21 Jan 2011 09:27:04 GMT Received: from d06av05.portsmouth.uk.ibm.com (d06av05.portsmouth.uk.ibm.com [9.149.37.229]) by d06nrmr1307.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p0L9QwPL1478718 for ; Fri, 21 Jan 2011 09:27:07 GMT Received: from d06av05.portsmouth.uk.ibm.com (loopback [127.0.0.1]) by d06av05.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p0L9QtFG017105 for ; Fri, 21 Jan 2011 02:26:56 -0700 From: Stefan Hajnoczi Date: Fri, 21 Jan 2011 09:26:39 +0000 Message-Id: <1295601999-14280-1-git-send-email-stefanha@linux.vnet.ibm.com> Subject: [Qemu-devel] [PATCH] docs: Document simple trace backend thread-safety limitation List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Stefan Hajnoczi , Prerna Saxena Signed-off-by: Stefan Hajnoczi --- docs/tracing.txt | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/docs/tracing.txt b/docs/tracing.txt index 963c504..d2499d9 100644 --- a/docs/tracing.txt +++ b/docs/tracing.txt @@ -133,6 +133,11 @@ source tree. It may not be as powerful as platform-specific or third-party trace backends but it is portable. This is the recommended trace backend unless you have specific needs for more advanced backends. +This trace backend is not thread-safe. In many cases this is not an issue +since the QEMU global mutex covers much of the codebase. Consider this +limitation when tracing utility functions that may be called from worker +threads with no synchronization. + ==== Monitor commands ==== * info trace -- 1.7.2.3