From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [PATCHv4 14/14] writeback: add new tracepoints Date: Fri, 23 Jul 2010 12:29:19 -0400 Message-ID: <20100723162919.GD29633@infradead.org> References: <1279897554-1526-1-git-send-email-dedekind1@gmail.com> <1279897554-1526-15-git-send-email-dedekind1@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Jens Axboe , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: Artem Bityutskiy Return-path: Received: from bombadil.infradead.org ([18.85.46.34]:34023 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752727Ab0GWQ3U (ORCPT ); Fri, 23 Jul 2010 12:29:20 -0400 Content-Disposition: inline In-Reply-To: <1279897554-1526-15-git-send-email-dedekind1@gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Fri, Jul 23, 2010 at 06:05:54PM +0300, Artem Bityutskiy wrote: > From: Artem Bityutskiy > > Add 2 new trace points to the periodic write-back wake up case, just like we do > in the 'bdi_queue_work()' function. Namely, introduce: > > 1. trace_writeback_wakeup(bdi) > 2. trace_writeback_wakeup_nothread(bdi) > > The first event is triggered every time we wake up a bdi thread to start > periodic background write-out. The second event is triggered only when the bdi > thread does not exist and should be created by the forker thread. > > This patch was suggested by Dave Chinner As mentioned before doing the wakeup just for the case where we really wake up the flusher thead is much better. It's not 100% clear for bdi_queue_work as we queue the work in either case, but I'd prefer to fix that one up as well (not in your series anyway)