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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 54FFDC433F5 for ; Sat, 16 Oct 2021 23:17:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 21E4660F57 for ; Sat, 16 Oct 2021 23:17:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235661AbhJPXTs (ORCPT ); Sat, 16 Oct 2021 19:19:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38224 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235619AbhJPXTr (ORCPT ); Sat, 16 Oct 2021 19:19:47 -0400 Received: from mail-ed1-x536.google.com (mail-ed1-x536.google.com [IPv6:2a00:1450:4864:20::536]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C6BFDC061765 for ; Sat, 16 Oct 2021 16:17:38 -0700 (PDT) Received: by mail-ed1-x536.google.com with SMTP id g10so54034429edj.1 for ; Sat, 16 Oct 2021 16:17:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=lO+JeZon3Yw+W2Ls04bPNSrFa5gQ48lttN3f2ez8GWI=; b=htF81CK/PiiFz10aajG5iWaEV5VK6wNyfinH08CTh6LuEZbAjdT/gbJ7ktXHwF3oxm lnYwB12eS99gBA3RqR/s+KdVVlpKVMKcSDLKaJ50HcLwONi0XKzS95S1f88VF0QuR0ee YNATFS2vB2cuPd+5Z/hjJpph72lQAY4pwT2WvzrMNeTg0Cy3hkX5xLknm5lLjmC8IYNB DHdWeSy3r2OOXf8bTs1cG/YELM40tNyhLQyiSbkure7otd2kY4H1d/bYtDf9ep5e/TCz rkQwdDZvBS/uDN3OniafeQgHpAG77OpkIz3UTTzzJoa7qjSHSj2HayfmmnprZYmlFMSb UnrA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=lO+JeZon3Yw+W2Ls04bPNSrFa5gQ48lttN3f2ez8GWI=; b=aLyieVs+rh62U+cbT71S072IxUY2QV2xznSFfTcYxRVMIRehoS/M0AegkIkPYzS2xz A9rLElR+3J9d2IEiGSh1OuKf2hvIEz3fyc8ZAKLXEmZd+c955Ir6/tkIXgagp5n5jc3r 6rC86B8Us/IUUxGO1e9t4PAkj/DvcwkTYwXXr/EScRrHXMuPn7E37VoL/oI/EMxH/lr9 w9Kl9v+esW5g7oY146pdjnLuVtTMISF5IODwvFoD2RPDm2e/lVI+KJX6HuKsdIpXoXUv oz40k8/wG1w5ZWvUJ6jHRkAxQr2B/FgHlZv/2xJ7/LqEryAu89CIhVEjkJPjlrcubq2L h5Mg== X-Gm-Message-State: AOAM530XKuB/nFjtb2g2KKkA+WKS/YG7SwW6kh/tdmv+gmg3gBV7NEUh IZ4K2+8cdALZLyryYOJJsZs= X-Google-Smtp-Source: ABdhPJwlNRK0TK7R+oXK0FXvDBdAopvnWwXjHNJAs5jE7zacq57XH4vhVtZE/IX173EGX2jRngROYg== X-Received: by 2002:a17:906:7c86:: with SMTP id w6mr17962183ejo.283.1634426257275; Sat, 16 Oct 2021 16:17:37 -0700 (PDT) Received: from [192.168.8.197] ([185.69.145.201]) by smtp.gmail.com with ESMTPSA id d22sm7078312ejj.47.2021.10.16.16.17.36 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 16 Oct 2021 16:17:36 -0700 (PDT) Message-ID: Date: Sun, 17 Oct 2021 00:16:57 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.1.2 Subject: Re: [PATCH 7/8] io_uring: arm poll for non-nowait files Content-Language: en-US To: Noah Goldstein Cc: "open list:IO_URING" , Jens Axboe References: <6e72153f8de78d836b9b7595a2a6f1c6a9f137b1.1634314022.git.asml.silence@gmail.com> From: Pavel Begunkov In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 10/16/21 23:57, Noah Goldstein wrote: > On Sat, Oct 16, 2021 at 5:19 PM Pavel Begunkov wrote: >> @@ -3238,7 +3220,8 @@ static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter) >> */ >> if (kiocb->ki_flags & IOCB_HIPRI) >> return -EOPNOTSUPP; >> - if (kiocb->ki_flags & IOCB_NOWAIT) >> + if ((kiocb->ki_flags & IOCB_NOWAIT) && >> + !(kiocb->ki_filp->f_flags & O_NONBLOCK)) >> return -EAGAIN; > > Instead of 2x branches on what appears to be the error (not hot path) The whole loop_rw_iter() is a slow path, we don't care enough -- Pavel Begunkov