From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f181.google.com (mail-il1-f181.google.com [209.85.166.181]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A83B2FC11 for ; Sat, 6 Apr 2024 02:10:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.181 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712369412; cv=none; b=Im98cmC3MLgTaNrGINSKYnJkOxpMyu1lWO15IWT7uIks5BdLfix9ZIEi5nos1Dc2ICv2tT6E/H+PXlf9q6PyVP4ilHHeWyldUWbG4CSqlAuhh1IWWW2ruT06eZrehYlD2t+prcM9gFsMIWRuLO0S9vuaZG9k7aQqlceoyTtJ1to= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712369412; c=relaxed/simple; bh=iPU1wDle54Dhh2Jag3TFgfIYW2xBm/4/mcjxBC9aWWc=; h=Message-ID:Date:MIME-Version:Subject:To:References:From: In-Reply-To:Content-Type; b=Du63Dech9eHTGqjtOFmVvX+VSoDRUtEPUmBeZJD4OysZwuSFGVlbUTr8HVyhE5m0uKsTHZHW3xDSAt1AnP47jCBysKju6mYHdyilAYuIs5p8c8XbArC3wvSq7wHNkp0MbT0epwslhQlsehcIHyW+TVT0nyPQG5hNeSX2KlWh62E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.dk; spf=pass smtp.mailfrom=kernel.dk; dkim=pass (2048-bit key) header.d=kernel-dk.20230601.gappssmtp.com header.i=@kernel-dk.20230601.gappssmtp.com header.b=OJ/f+Zky; arc=none smtp.client-ip=209.85.166.181 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.dk Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kernel.dk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20230601.gappssmtp.com header.i=@kernel-dk.20230601.gappssmtp.com header.b="OJ/f+Zky" Received: by mail-il1-f181.google.com with SMTP id e9e14a558f8ab-36990f24098so87365ab.0 for ; Fri, 05 Apr 2024 19:10:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1712369410; x=1712974210; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:references:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=1cCv5VcWhStgJ4vCE9L+2KiQe3Q2pQoluor1fRLFK9E=; b=OJ/f+ZkyG3cZl6xcriW+jcc5SzhHLzcRQhi4fk7Wo9GO3OqPAWei4wZJcBu+EYhHgG MFU8hxTWQNk/NWoWVCqwhKqsZPEjT2XPZD9cPzWzWBmTdTlxze0gMBuh01qdzXosDhEL f8z51TZAf1NUyWvujlh9X+B3rq3zj0DJOW5Wi8TyjmmFEJRZ4YJm5LhU3PraFSd/ryPR NIT3sAEFz3Q1LVFDYlYMJqgRqpUxivQaNzHft/4cgtoOMpDhjCcjVSIq08I20raUkyZz JyF2SwSTlylM/0jByHXdj3wCSJ2DE7XHXFwyt9DbZmF/gBO/qqINzFBDNB216HhkTDjh R+dw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1712369410; x=1712974210; h=content-transfer-encoding:in-reply-to:from:references: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=1cCv5VcWhStgJ4vCE9L+2KiQe3Q2pQoluor1fRLFK9E=; b=ldVmev5YwdsaGWMc2SPhV4rwjBsGUXSDO8j4ce+GlthKUSFJC8VXSWGAJ0k1kLwpX4 URV3e5ORaLZmmS2EzjP4SCAfGOO277Smsqni5E9mP3/Z19K3k81KAZUIHnlNmcY15t4g GuhfHkoaUXQc3v6jeGeHm07/gcQm1B33mELaNYHE3/GJb6aEo6JKEzLUhGAKsCcwT0Jn wcDIfJTUem7pu71HC2rz64iE8C9hK+UvvUqlexAHj0z77cPRL/Ogea9VQrNAI9YO7Mmd Fbv3Hv7m3jSnXJDngRZLxSbpP2hzAbdcH2d+a7kcKXe1RsEjfRcxFFKXh+olU+v3jo/L IbYg== X-Forwarded-Encrypted: i=1; AJvYcCWeKofc6Ct9YTFh5kjV9kb9owCj+y/5uCiZJnGfwxf0i6sEagLw6h9eNYhQAS98K6R9yrnkKpQshLHWGnl+uwxEahEbE8q8 X-Gm-Message-State: AOJu0YzZnQJdZtgA9ENkcKmsXjtcBfc/LBlAhRV84rVo8TxYZji+RWJn UZKIjczBw/qM8SrS3zUbi37QdpsHRCqUhcR+ftLRPBU+yJkydRbYaZn6XKtGZj0= X-Google-Smtp-Source: AGHT+IGN8BSnqjv3LU00TTGUDfx8VQfSQp0U3i+zESsBq9d8LHP4DpckfjoiRKtuga7gxqJKeYYQEg== X-Received: by 2002:a05:6e02:19cd:b0:368:9b64:fa7a with SMTP id r13-20020a056e0219cd00b003689b64fa7amr3938452ill.0.1712369409735; Fri, 05 Apr 2024 19:10:09 -0700 (PDT) Received: from [172.19.0.169] ([99.196.135.167]) by smtp.gmail.com with ESMTPSA id s5-20020a92cb05000000b0036a0e23db86sm612548ilo.33.2024.04.05.19.10.02 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 05 Apr 2024 19:10:09 -0700 (PDT) Message-ID: Date: Fri, 5 Apr 2024 20:10:02 -0600 Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 6.8 015/715] io_uring: remove unconditional looping in local task_work handling Content-Language: en-US To: Jiri Slaby , Sasha Levin , linux-kernel@vger.kernel.org, stable@vger.kernel.org References: <20240324223455.1342824-1-sashal@kernel.org> <20240324223455.1342824-16-sashal@kernel.org> <2ff5d891-2120-475d-be8e-82bf20a8b7b7@kernel.dk> <29df48ef-aafe-4918-b903-0aabda94fd0b@kernel.org> From: Jens Axboe In-Reply-To: <29df48ef-aafe-4918-b903-0aabda94fd0b@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 4/4/24 1:06 AM, Jiri Slaby wrote: > On 02. 04. 24, 15:41, Jens Axboe wrote: >> On 4/2/24 2:12 AM, Jiri Slaby wrote: >>> On 24. 03. 24, 23:23, Sasha Levin wrote: >>>> From: Jens Axboe >>>> >>>> [ Upstream commit 9fe3eaea4a3530ca34a8d8ff00b1848c528789ca ] >>>> >>>> If we have a ton of notifications coming in, we can be looping in here >>>> for a long time. This can be problematic for various reasons, mostly >>>> because we can starve userspace. If the application is waiting on N >>>> events, then only re-run if we need more events. >>> >>> This commit breaks test/recv-multishot.c from liburing: >>> early error: res 4 >>> test stream=1 wait_each=0 recvmsg=0 early_error=0 defer=1 failed >>> >>> The behaviour is the same in 6.9-rc2 (which contains the commit too). >>> >>> Reverting the commit on the top of 6.8.2 makes it pass again. >>> >>> Should the test be updated or is the commit wrong? >> >> The commit is fine, it's the test that is buggy. Sometimes test cases >> make odd assumptions that are just wrong but happen to work, for some >> definition of work. Eg it would work fine on an idle system, but not >> necessarily if not. For this one, the fix is in liburing: >> >> https://git.kernel.dk/cgit/liburing/commit/test/recv-multishot.c?id=a1d5e4b863a60af93d0cab9d4bbf578733337a90 > > Thanks, that worked. > > Any plans to release 2.6 with the above? > > Note that for 2.4->2.5 update I also needed to take 9dc95a03e4a76 from > post-2.5. Yep, 2.6 should be released very soon. -- Jens Axboe