From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932092AbVHTHLO (ORCPT ); Sat, 20 Aug 2005 03:11:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932093AbVHTHLO (ORCPT ); Sat, 20 Aug 2005 03:11:14 -0400 Received: from liaag2ag.mx.compuserve.com ([149.174.40.158]:17811 "EHLO liaag2ag.mx.compuserve.com") by vger.kernel.org with ESMTP id S932092AbVHTHLN (ORCPT ); Sat, 20 Aug 2005 03:11:13 -0400 Date: Sat, 20 Aug 2005 03:07:43 -0400 From: Chuck Ebbert <76306.1226@compuserve.com> Subject: Re: [patch 2.6.13-rc6] i386: semaphore ownership tracking To: Andrew Morton Cc: mingo@elte.hu, ak@suse.de, torvalds@osdl.org, linux-kernel@vger.kernel.org Message-ID: <200508200310_MC3-1-A7BC-D1C0@compuserve.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 19 Aug 2005 at 20:02:27 -0700, Andrew Morton wrote: > Chuck Ebbert <76306.1226@compuserve.com> wrote: > > > > This patch enables tracking semaphore ownership. > > Why? I can't think of any bug in recent years which needed this.. It might be useful in new driver development. OTOH it is really ugly even if it's a small patch. I did get an education from it, though. The usb-storage threads on my system were sleeping on semaphores they already owned, making me wonder if my patch really worked. It turns out that code in scsiglue.c does an up() to wake them without ever acquiring the semaphore. __ Chuck