From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [PATCH 1/6] writeback: fix writeback completion notifications Date: Tue, 08 Jun 2010 21:50:31 +0200 Message-ID: <4C0E9F07.1020805@kernel.dk> References: <20100608161424.GA11735@lst.de> <20100608161434.GB11735@lst.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: linux-fsdevel@vger.kernel.org To: Christoph Hellwig Return-path: Received: from 0122700014.0.fullrate.dk ([95.166.99.235]:35170 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754724Ab0FHTuc (ORCPT ); Tue, 8 Jun 2010 15:50:32 -0400 In-Reply-To: <20100608161434.GB11735@lst.de> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On 08/06/10 18.14, Christoph Hellwig wrote: > The code dealing with bdi_work->state and completion of a bdi_work is a > major mess currently. This patch makes sure we directly use one set of > flags to deal with it, and use it consistently, which means: > > - always notify about completion from the rcu callback. We only ever > wait for it from on-stack callers, so this simplification does not > even cause a theoretical slowdown currently. It also makes sure we > don't miss out on the notification if we ever add other callers to > wait for it. It's still more costly to actually do the rcu callback, but I guess it's not too big of a deal. > - make earlier completion notification depending on the on-stack > allocation, not the sync mode. If we introduce new callers that > want to do WB_SYNC_NONE writeback from on-stack callers this will > be nessecary. > > Also rename bdi_wait_on_work_clear to bdi_wait_on_work_done and inline > a few small functions into their only caller to make the code > understandable. Looks good to me. -- Jens Axboe