From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932406AbaESNSa (ORCPT ); Mon, 19 May 2014 09:18:30 -0400 Received: from mail-ee0-f43.google.com ([74.125.83.43]:57445 "EHLO mail-ee0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754403AbaESNS2 (ORCPT ); Mon, 19 May 2014 09:18:28 -0400 Message-ID: <537A0495.60107@gmail.com> Date: Mon, 19 May 2014 15:18:13 +0200 From: "Michael Kerrisk (man-pages)" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: Jeff Layton , "linux-man@vger.kernel.org" , lkml , Linux-Fsdevel , Andy Lutomirski CC: mtk.manpages@gmail.com Subject: OFD locks and deadlock detection Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jeff, I just happened to notice : commit 57b65325fe34ec4c917bc4e555144b4a94d9e1f7 Author: Jeff Layton Date: Mon Feb 3 12:13:09 2014 -0500 locks: skip deadlock detection on FL_FILE_PVT locks And then this thread: http://thread.gmane.org/gmane.linux.file-systems/81318/focus=81327 From: Jeff Layton redhat.com> Subject: [PATCH v5 13/14] locks: skip deadlock detection on FL_FILE_PVT locks Date: 2014-01-09 14:19:46 GMT I think it's pretty important to document that. All implementations of traditional process-associated (.k.a. "POSIX") locks that I've ever come across do detect deadlocks, so it's important to note that OFD locks do not. I plan to add the following text to the fcntl(2) page: [[ In the current implementation, no deadlock detection is performed for open file description locks. (This contrasts with process-associated record locks, for which the kernel does perform deadlock detection.) ]] Okay? cheers, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/