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=-5.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, 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 BA169C433DB for ; Mon, 22 Mar 2021 13:46:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6943A6198C for ; Mon, 22 Mar 2021 13:46:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230335AbhCVNpf (ORCPT ); Mon, 22 Mar 2021 09:45:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39638 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230084AbhCVNpE (ORCPT ); Mon, 22 Mar 2021 09:45:04 -0400 Received: from mail-pl1-x62d.google.com (mail-pl1-x62d.google.com [IPv6:2607:f8b0:4864:20::62d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DA5A8C061574 for ; Mon, 22 Mar 2021 06:45:03 -0700 (PDT) Received: by mail-pl1-x62d.google.com with SMTP id ay2so6599651plb.3 for ; Mon, 22 Mar 2021 06:45:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language:content-transfer-encoding; bh=Tli/spzAAOQs7G7CWoRwnyrPheanSBTPWz+PkrqnQDo=; b=EFX0K+T8oib4zxXOK9VJNLMnAGI8JcVikDircjuBD1ULc4BFruDfsq194uDk9M4ugW Mb3mCkBosKECRLlQMeLysv2hqszMlXIUOzXD2ZRTiSUmSBhyto/V3TJoqNdLSYQDePts ex4qCMxdY+ycNRp9qtagtiTMS3EIvF1C6FQRyv/ul7RYL2nsSDVHMPbMfehdYmVg8flG cz/1KVmROdaoBDEmneT5giYzCbYVuAhsAExpONWPsfRamumYFL4mQo6KUF8yVPWy++P9 +L/Xc17zWxC5I82DL0c0fQj69dQkDLPykbMTRAjwpQxsrQjr0Q3etLZ+7Z9+k4PdkoQu Gg8w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=Tli/spzAAOQs7G7CWoRwnyrPheanSBTPWz+PkrqnQDo=; b=QN4RvEjqA3xqEWrSdqD17tw+Vh6FuvrOmwks/UsWNnqwFd5KTg/qBEh0nDnBTD7sSc jt9cIGYEmPTfXguyUnhmkjpIOH4S8fedDo7Ac2VufhfyGD+w4KxTeKYPu+UrI8X/JOKx VlUgbOEOc6JARc2DaZVnuOyRLRZ+WICzgL1gn9+KcbVhdBOQqpCQ7hqnRcWgwnjC5V39 vuxm8NCwbFySjWdeeeuxQCVBBO/Njf3qQCAJi/98q5j6gedGNpsgxt7IxOi6mZzG7AQz o4fHZYE/mpHB37WUVd2Y74gDesjrfxb42g9EvfsF4b2GVLieBfGXmVzUE7+Nq/9nSSKu MS7g== X-Gm-Message-State: AOAM530RiE/Z6w3wy2eimm28vWEQTd+qG0gtkvvkxQV7SEh/xElsjCBo 0I9gI2yAuQ6FKXvvdvRPCO+tGJHBy/KVHg== X-Google-Smtp-Source: ABdhPJyKVi+2HdpHcRj4dueLZcee47ycq9ObEkkDKN2non3W1sJTSicJ2i9xj7Af4uPfoHnViw0jGw== X-Received: by 2002:a17:90a:c201:: with SMTP id e1mr13497867pjt.30.1616420703009; Mon, 22 Mar 2021 06:45:03 -0700 (PDT) Received: from [192.168.1.134] ([66.219.217.173]) by smtp.gmail.com with ESMTPSA id cv3sm14892705pjb.9.2021.03.22.06.45.02 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 22 Mar 2021 06:45:02 -0700 (PDT) Subject: Re: [PATCH 03/11] io_uring: optimise out task_work checks on enter To: Pavel Begunkov , io-uring@vger.kernel.org References: From: Jens Axboe Message-ID: Date: Mon, 22 Mar 2021 07:45:01 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 3/21/21 7:58 PM, Pavel Begunkov wrote: > io_run_task_work() does some extra work for safety, that isn't actually > needed in many cases, particularly when it's known that current is not > exiting and in the TASK_RUNNING state, like in the beginning of a > syscall. Is this really worth it? -- Jens Axboe