From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753543Ab2LYDSm (ORCPT ); Mon, 24 Dec 2012 22:18:42 -0500 Received: from mail-da0-f46.google.com ([209.85.210.46]:56087 "EHLO mail-da0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753483Ab2LYDSk (ORCPT ); Mon, 24 Dec 2012 22:18:40 -0500 Date: Mon, 24 Dec 2012 19:18:35 -0800 From: Tejun Heo To: Borislav Petkov , Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: [PATCH 25/25] ipc: don't use [delayed_]work_pending() Message-ID: <20121225031835.GD10220@mtj.dyndns.org> References: <1356141435-17340-1-git-send-email-tj@kernel.org> <1356141435-17340-26-git-send-email-tj@kernel.org> <20121221181523.0e0998e4.akpm@linux-foundation.org> <20121222022210.GA30177@htj.dyndns.org> <20121222110929.GA3567@liondog.tnic> <20121224183334.GB11817@htj.dyndns.org> <20121224185555.GA5344@liondog.tnic> <20121224190723.GE11817@htj.dyndns.org> <20121224193258.GB5344@liondog.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20121224193258.GB5344@liondog.tnic> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Borislav. On Mon, Dec 24, 2012 at 08:32:58PM +0100, Borislav Petkov wrote: > Ok, understood. I have only one question: how do you make sure > schedule_work() is used only in cold paths? Hot and cold are relative terms and unless someone is doing things like invoking queue_work() from high-frequency interrupt handler, the level of overhead from queue_work() isn't likely to matter. The best way to deal with such hot paths would differ depending on the specifics of each hot path - ie. bouncing to workqueue from IRQ handler would be better handled by threaded IRQ handlers. At this point, especially given how all of work_pending() users are way too cold for any of this to matter, I don't think we need to worry about this. > Btw, there's __cancel_delayed_work() which is not used anywhere and it > could be deleted AFAICT. Yeah, there are several interfaces which are being deprecated. They'll be gone in a few cycles. Thanks. -- tejun