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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 71108C4646D for ; Mon, 6 Aug 2018 16:49:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1E01421A28 for ; Mon, 6 Aug 2018 16:49:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="cTBAz4hX" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1E01421A28 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731810AbeHFS7d (ORCPT ); Mon, 6 Aug 2018 14:59:33 -0400 Received: from mail-io0-f173.google.com ([209.85.223.173]:33919 "EHLO mail-io0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728475AbeHFS7d (ORCPT ); Mon, 6 Aug 2018 14:59:33 -0400 Received: by mail-io0-f173.google.com with SMTP id l7-v6so11612204ioj.1; Mon, 06 Aug 2018 09:49:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=/eKqIfkrpHsq7u3VSrp7q/25kt84IdzZyAUgLYIEoWU=; b=cTBAz4hXFudOyI0l8TXEF/Zw/bT6PB51Pv7MIyHqV4A+IppvjMf8OszG0sMs0O1XJV UAFXwrqv8M3lkVvyjQJQhcu5jVCsQ8JuYFhow5JGjM1BW6QpCXVjs4IYHMnhH66ta7YU 5zmL978bBguEkAnTXiXTUFKAVGQK/AjAlyJSQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=/eKqIfkrpHsq7u3VSrp7q/25kt84IdzZyAUgLYIEoWU=; b=XRvSrlQY5seCCITBC/3+/+kVDt2iz4c61MmZppampkgN/TeExnOSPrK20kB+5Wj4dp cynm9ZeE0gC7nULywNlcoQ5vLXh+pRYSgPdnQ5h4EAyjxPxxuSjiqpumMWQYbq3C11W6 /qmX/Xy4Nu56ItRtPGpq+5veAI7Z0Y+kF6MjrNvQ9ySR3IjsY+Tt0ClEd3OgwUi0sZsa UEkuBltZ3R1gAuJLpPTfmWvn3A0HwyD5d89vzytJUZ5Sk+fvRVhgnAHngREyxmi6e5gv 3pIZl0b4xuwCvQ1CNVzCuP2QHdy82A0+trNLk1vYTqeeSB1AKeufhx0ujZOAt/vZXBLH xhyg== X-Gm-Message-State: AOUpUlEpsdotd0M8cfmM3zrDE6xuBMC9jiKo17r94MyprVWoT3iywePY lsRF7W29HK0Rl8iSELzIKZj5e49GYZxTumHF3eBZwA== X-Google-Smtp-Source: AA+uWPyPK3KELWBwHmSH4ngK1ixA0uW8ishHOIod472CzXgh0JeIzZBCccgJvE9R3Pc/S2is/jxxhGwCnO5E4W1ysHM= X-Received: by 2002:a6b:7a05:: with SMTP id h5-v6mr16473397iom.238.1533574175920; Mon, 06 Aug 2018 09:49:35 -0700 (PDT) MIME-Version: 1.0 References: <20180806083058.14724-1-hch@lst.de> In-Reply-To: <20180806083058.14724-1-hch@lst.de> From: Linus Torvalds Date: Mon, 6 Aug 2018 09:49:24 -0700 Message-ID: Subject: Re: aio poll V22 (aka 2.0) To: Christoph Hellwig Cc: Al Viro , Avi Kivity , linux-aio@kvack.org, linux-fsdevel , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 6, 2018 at 1:31 AM Christoph Hellwig wrote: > > As our dear leader didn't like the ->poll_mask method this tries to > implement the behavior using plain old ->poll which is rather painful. I'm not seeing what's painful for this. Looking at the patches, this is *much* more straightforward than your previous patch, It adds refcounting to aio_iocb, but that's *much* better than messing up every other subsystem. Or is there some follow-up patches that are pending but you didn't post that are the painful part? Because the diffstat says that this second version is *way* less painful, at about 200 lines of code in a couple of files, mostly aio, vs ~700 lines of changes all over the place, together with a performance regression. Linus