From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753733Ab1J0QRI (ORCPT ); Thu, 27 Oct 2011 12:17:08 -0400 Received: from mail-qy0-f174.google.com ([209.85.216.174]:42791 "EHLO mail-qy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751094Ab1J0QRH (ORCPT ); Thu, 27 Oct 2011 12:17:07 -0400 Date: Thu, 27 Oct 2011 09:17:01 -0700 From: Tejun Heo To: Vivek Goyal Cc: axboe@kernel.dk, ctalbott@google.com, rni@google.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH UPDATED 10/13] block, cfq: unlink cfq_io_context's immediately Message-ID: <20111027161701.GB29899@google.com> References: <1319593719-19132-1-git-send-email-tj@kernel.org> <1319593719-19132-11-git-send-email-tj@kernel.org> <20111026213107.GI24261@google.com> <20111027143119.GD7491@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20111027143119.GD7491@redhat.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Thu, Oct 27, 2011 at 10:31:19AM -0400, Vivek Goyal wrote: > On Wed, Oct 26, 2011 at 02:31:07PM -0700, Tejun Heo wrote: > > BUG_ON(atomic_long_read(&ioc->refcount) <= 0); > > + if (locked_q) > > + lockdep_assert_held(locked_q->queue_lock); > > > > Looks like lockdep_assert_held() can't be used if !CONFIG_LOCKDEP. So > Jens had put following patch to fix one compilation issue. You might > want to provide a null definition of lockdep_assert_held() in case > of !CONFIG_LOCKDEP. > > commit 334c2b0b8b2ab186fa198413386cba41fffcb4f2 > Author: Jens Axboe > Date: Tue Oct 25 15:51:48 2011 +0200 > > blk-throttle: use queue_is_locked() instead of lockdep_is_held() > > We can't use the latter if !CONFIG_LOCKDEP. > > Reported-by: Sedat Dilek > Signed-off-by: Jens Axboe Eh? lockdep.h has dummy definition if !CONFIG_LOCKDEP. If lockdep_is_held() is causing compilation failure on !CONFIG_LOCKDEP, it's more likely to be have been caused by missing include than anything else. Jens, what was the failure? lockdep_is_held() provides way better protection against locking mistakes than spin_is_locked(). Thanks. -- tejun