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=-5.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 9C92BC433E0 for ; Tue, 11 Aug 2020 14:05:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 65FF82076C for ; Tue, 11 Aug 2020 14:05:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="V16zZAFK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728705AbgHKOFp (ORCPT ); Tue, 11 Aug 2020 10:05:45 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:57868 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728622AbgHKOFo (ORCPT ); Tue, 11 Aug 2020 10:05:44 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1597154742; 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=eaUyZri1JTLFO+mMoLsk80VcTVuthOVVi1PbXrcLMgg=; b=V16zZAFKkvVPhHNfH6faZw0yrrmi2qI//5yK5u+nM0jTlsy4PcYSAXHiLa8ZK1Qqxxxid/ PEbOzkr8HDopX7Ob3NuLjy7nseYrt1qL0OPcpkNk+CzDtw/Bzp7YLpWwH8InCPSQ4/EUHK L4mYvLM+H97/97/I9jPUHCwkDWWRPsY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-530-gpgahVDuPAGrX-0e__X6yA-1; Tue, 11 Aug 2020 10:05:40 -0400 X-MC-Unique: gpgahVDuPAGrX-0e__X6yA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7FF038031DC; Tue, 11 Aug 2020 14:05:28 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.40.192.186]) by smtp.corp.redhat.com (Postfix) with SMTP id C889260E1C; Tue, 11 Aug 2020 14:05:26 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Tue, 11 Aug 2020 16:05:28 +0200 (CEST) Date: Tue, 11 Aug 2020 16:05:25 +0200 From: Oleg Nesterov To: Jens Axboe Cc: Peter Zijlstra , Jann Horn , io-uring , stable , Josef Subject: Re: [PATCH 2/2] io_uring: use TWA_SIGNAL for task_work if the task isn't running Message-ID: <20200811140525.GE21797@redhat.com> References: <1629f8a9-cee0-75f1-810a-af32968c4055@kernel.dk> <20200811064516.GA21797@redhat.com> <20200811065659.GQ3982@worktop.programming.kicks-ass.net> <20200811071401.GB21797@redhat.com> <20200811074538.GS3982@worktop.programming.kicks-ass.net> <20200811081033.GD21797@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 08/11, Jens Axboe wrote: > > I'd really like to get this done at the same time as the io_uring > change. Are you open to doing the READ_ONCE() based JOBCTL_TASK_WORK > addition for 5.9? Yes, the patch looks fine to me. In fact I was going to add this optimization from the very beginning, but then decided to make that patch as simple as possible. And in any case I personally like this change much more than 1/2 + 2/2 which I honestly don't understand ;) Oleg.