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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CD06FC47088 for ; Thu, 1 Dec 2022 18:41:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230190AbiLASlT (ORCPT ); Thu, 1 Dec 2022 13:41:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38846 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229722AbiLASlQ (ORCPT ); Thu, 1 Dec 2022 13:41:16 -0500 Received: from mail-io1-xd2a.google.com (mail-io1-xd2a.google.com [IPv6:2607:f8b0:4864:20::d2a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 99E6ABB7E0 for ; Thu, 1 Dec 2022 10:41:15 -0800 (PST) Received: by mail-io1-xd2a.google.com with SMTP id b2so1612207iof.12 for ; Thu, 01 Dec 2022 10:41:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=FJcBqkJuc1O3n5xY+XGahxTgpCrWh2DUx8QxErVJvjI=; b=5ZelWTK9N5aqGvkSgZAU0x3yqA3FgGhaYF70hbG1rXpM2OciDQ3QPvIoWnFsVCBsW7 nGSCU9A757Z7mGhq0N4B1OMMwAOwiiGEyn9wMuBwuSp2CxsOJsMgEw9tJ9jXuUbyS9PF HtmAM5Wsjwc+i5nrNuR0CO5t9OT3GqmNTuGFmxoc/wGVkVYxSZd8KyBHKPO2SLQIw2sa vbK//4f/er5pz2KCZTOonrELgX7vtUb/ygq5w6+M5GFsnjonzY1hkv2p7o8yEv6cNpvy ojv5o28x2Ds6RUBC8uDS/Av0RsDhYmgrrt0BsIMIbwKJ4TnUDiqdtdSAVrtA6sCra4Uo XyHQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=FJcBqkJuc1O3n5xY+XGahxTgpCrWh2DUx8QxErVJvjI=; b=hzQqgLBWV/yFVpEL9Fk1IkHu00CNEM+WtPGMEPldZCmqQCDvl7pnixEvb/U5m1Fo2I XqY5knuDohfL79k2K4sOt1eZG1WkZgijDnYotGEMZmyBTTIXipuBmhnixW9roxxnL5yp 8Epx2poMscQgoHwfy5IBGviWvb6+0uYEXnHNoC1D5oluMN9sjvOBOoaxwN8MiowR52cm aAcIlVfQL7sID97t9pp2KMeaX9z7qeFM2anVxrCdk1i+OZCadtxX53jlG7rNgBYYSZ40 kU62vYKDIS3qKeKcYVFbMBAKXEymNK/HQcpfo32QYVpZyX0gx7vaEQoHHa4frdEXDeYd F0Ug== X-Gm-Message-State: ANoB5pks2yWWYop/coRIrqNaUYtUV7FRd8c2auqKo12i45C3aDIdXGyj viDzyxm/m/f13kG+GcRGU/0atw== X-Google-Smtp-Source: AA0mqf4HLgYNYDjyELelhCkWMtLx4c8wyj24KGj8KIHy9QjMYn0XtSZvrgYqG8Jfh8WgMvo3/CBClA== X-Received: by 2002:a02:5442:0:b0:389:d81a:1d80 with SMTP id t63-20020a025442000000b00389d81a1d80mr11528617jaa.80.1669920074867; Thu, 01 Dec 2022 10:41:14 -0800 (PST) Received: from [192.168.1.94] ([207.135.234.126]) by smtp.gmail.com with ESMTPSA id cn23-20020a0566383a1700b00374bf3b62a0sm1889875jab.99.2022.12.01.10.41.13 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 01 Dec 2022 10:41:14 -0800 (PST) Message-ID: Date: Thu, 1 Dec 2022 11:41:13 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:102.0) Gecko/20100101 Thunderbird/102.5.0 Subject: Re: [PATCH 6/6] eventpoll: add support for min-wait Content-Language: en-US To: Soheil Hassas Yeganeh Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Willem de Bruijn , Shakeel Butt References: <20221030220203.31210-1-axboe@kernel.dk> <20221030220203.31210-7-axboe@kernel.dk> <4764dcbf-c735-bbe2-b60e-b64c789ffbe6@kernel.dk> <8d195905-a93f-d342-abb0-dd0e0f5a5764@kernel.dk> From: Jens Axboe In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/1/22 11:39 AM, Soheil Hassas Yeganeh wrote: > On Thu, Dec 1, 2022 at 1:00 PM Jens Axboe wrote: >> >>>>> @@ -1845,6 +1891,18 @@ static int ep_poll(struct eventpoll *ep, struct epoll_event __user *events, >>>>> ewq.timed_out = true; >>>>> } >>>>> >>>>> + /* >>>>> + * If min_wait is set for this epoll instance, note the min_wait >>>>> + * time. Ensure the lowest bit is set in ewq.min_wait_ts, that's >>>>> + * the state bit for whether or not min_wait is enabled. >>>>> + */ >>>>> + if (ep->min_wait_ts) { >>>> >>>> Can we limit this block to "ewq.timed_out && ep->min_wait_ts"? >>>> AFAICT, the code we run here is completely wasted if timeout is 0. >>> >>> Yep certainly, I can gate it on both of those conditions. >> Looking at this for a respin, I think it should be gated on >> !ewq.timed_out? timed_out == true is the path that it's wasted on >> anyway. > > Ah, yes, that's a good point. The check should be !ewq.timed_out. The just posted v4 has the check (and the right one :-)) -- Jens Axboe