From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1D933C4363D for ; Fri, 2 Oct 2020 19:10:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B394A20795 for ; Fri, 2 Oct 2020 19:10:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="UO32msFo"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="kyckBGqy" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387692AbgJBTKn (ORCPT ); Fri, 2 Oct 2020 15:10:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41850 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726215AbgJBTKn (ORCPT ); Fri, 2 Oct 2020 15:10:43 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 333B3C0613D0; Fri, 2 Oct 2020 12:10:43 -0700 (PDT) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1601665840; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=eJktxSNhWJM/BgeMFlAldxUGknWBDzKoGcVcbfFdWEU=; b=UO32msFoUsnCGcCU/nloBL/pLMHuNB23dbBu2ZIdqhsgz9R9A47l+q5WEy5Wb5i5jVkG/t tyIp+WV6ug3qNcoGQqihonvjKn1XL3j/7WK9/0n3+yxMQuRwcYTuDBzCwBOO8kmM+7Q9Vp KNkeJos/TCphe8Lx/DxqHll/LW0UdwymfyzgzcCVpfAZJRzMl3ZY+k+mzVjr0txX7lHzsM gPPQl2Ohob8X6I7oCEmllAvLmo1CYaURiXlcF8Y9HmO1ceRGr6Ku27AV68XPLGjj/KsMgs 2yGmUh8SVcU8aEM07fXjecPGvRlQpwG7ki2y87i6EEjuRGmJhwe882dwOEH4fA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1601665840; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=eJktxSNhWJM/BgeMFlAldxUGknWBDzKoGcVcbfFdWEU=; b=kyckBGqyHRgAFJ5nX3wgecTnJO8ACh6+1GODnqeRu6rUz0IBTSZYtE6DSkEdH4UCm/ne+m 8CJrryjS68tFs6Cg== To: Jens Axboe , Oleg Nesterov Cc: linux-kernel@vger.kernel.org, io-uring@vger.kernel.org, peterz@infradead.org Subject: Re: [PATCH 3/3] task_work: use TIF_TASKWORK if available In-Reply-To: <4c9dbcc4-cae7-c7ad-8066-31d49239750a@kernel.dk> References: <20201001194208.1153522-1-axboe@kernel.dk> <20201001194208.1153522-4-axboe@kernel.dk> <20201002151415.GA29066@redhat.com> <871rigejb8.fsf@nanos.tec.linutronix.de> <4c9dbcc4-cae7-c7ad-8066-31d49239750a@kernel.dk> Date: Fri, 02 Oct 2020 21:10:40 +0200 Message-ID: <87y2kocukv.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Fri, Oct 02 2020 at 09:52, Jens Axboe wrote: > On 10/2/20 9:31 AM, Thomas Gleixner wrote: >>> This way task_work_run() doesn't need to clear TIF_NOTIFY_SIGNAL and it can >>> have more users. >> >> I think it's fundamentaly wrong that we have several places and several >> flags which handle task_work_run() instead of having exactly one place >> and one flag. > > I don't disagree with that. I know it's not happening in this series, but > if we to the TIF_NOTIFY_SIGNAL route and get all archs supporting that, > then we can kill the signal and notify resume part of running task_work. > And that leaves us with exactly one place that runs it. > > So we can potentially improve the current situation in that regard. I'll think about it over the weekend.