From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from cloud48395.mywhc.ca (cloud48395.mywhc.ca [173.209.37.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F3B5C195 for ; Wed, 14 Aug 2024 00:09:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=173.209.37.211 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723594187; cv=none; b=pIH3REJh98BBedzqVJZOgt3EvPrPDpHlP1n/yaP0Z103+qsy1xFLxnOLsWmOABIjy1xhcI6295rKnVLZZ306s0hxsVhEEz2r+DhNzt0X/nTmh64bnMDdn6+YewnzS7r6hVrG7GG/cxO4iev+NrQOWZLnfI4EJPPnZnFa8BTNJkc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723594187; c=relaxed/simple; bh=w5BRKB/qXJqkIiZknMLkaY1g+GowXtdrpHVYYWiXp/8=; h=Message-ID:Subject:From:To:Date:In-Reply-To:References: Content-Type:MIME-Version; b=f+RKTXbC4uJlPpvoYblDsqiWwO9lLKqesRKOO0u6hmxsm6ftI1DtA4MWzpOz7+h0bTORHbw5/uESUiIgbJrVgiul97ahm24ZeZN72px+CcmRHxl1A7ib0KtxOo5lEjwmxJJ/bp/zCRT2aIfxriMlXr1CtdS1QEmefdEmClQidYE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=trillion01.com; spf=pass smtp.mailfrom=trillion01.com; arc=none smtp.client-ip=173.209.37.211 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=trillion01.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=trillion01.com Received: from [45.44.224.220] (port=58188 helo=[192.168.1.177]) by cloud48395.mywhc.ca with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96.2) (envelope-from ) id 1se1aB-0003mc-12; Tue, 13 Aug 2024 20:09:43 -0400 Message-ID: Subject: Re: [PATCH] io_uring/napi: remove duplicate io_napi_entry timeout assignation From: Olivier Langlois To: Jens Axboe , Pavel Begunkov , io-uring@vger.kernel.org Date: Tue, 13 Aug 2024 20:09:42 -0400 In-Reply-To: References: <145b54ff179f87609e20dffaf5563c07cdbcad1a.1723423275.git.olivier@trillion01.com> <05255cc5136254574b884b5e10aae7cf8301662a.camel@trillion01.com> <8c1ee6ab-8425-4d13-80f5-ff085d12dc91@kernel.dk> <8887f2d97c1dafb6ceaf9f5c492457f642f532dd.camel@trillion01.com> <5730c0c1-73cb-42b5-8af3-afe60529f57d@kernel.dk> Autocrypt: addr=olivier@trillion01.com; prefer-encrypt=mutual; keydata=mQINBFYd0ycBEAC53xedP1NExPwtBnDkVuMZgRiLmWoQQ8U7vEwt6HVGSsMRHx9smD76i 5rO/iCT6tDIpZoyJsTOh1h2NTn6ZkoFSn9lNOJksE77/n7HNaNxiBfvZHsuNuI53CkYFix9JhzP3t g5nV/401re30kRfA8OPivpnj6mZhU/9RTwjbVPPb8dPlm2gFLXwGPeDITgSRs+KJ0mM37fW8EatJs 0a8J1Nk8wBvT7ce+S2lOrxDItra9pW3ukze7LMirwvdMRC5bdlw2Lz03b5NrOUq+Wxv7szn5Xr9f/ HdaCH7baWNAO6H/O5LbJ3zndewokEmKk+oCIcXjaH0U6QK5gJoO+3Yt5dcTo92Vm3VMxzK2NPFXgp La7lR9Ei0hzQ0zptyFFyftt9uV71kMHldaQaSfUTsu9dJbnS2kI/j+F2S1q6dgKi3DEm0ZRGvjsSG rkgPJ5T16GI1cS2iQntawdr0A1vfXiB9xZ1SMGxL/l6js9BVlIx/CBGOJ4L190QmxJlcAZ2VnQzrl ramRUv01xb00IPJ5TBft5IJ+SY0FnY9pIERIl6w9khwLt/oGuKNmUHmzJGYoJHYfh72Mm8RQ1R/JS o6v85ULBGdEC3pQq1j//OPyH3egiXIwFq6BtULH5CvsxQkSqgj1MpjwfgVJ8VbjNwqwBXHjooEORj vFQqWQki6By3QARAQABtDJPbGl2aWVyIExhbmdsb2lzIChNeSBrZXkpIDxvbGl2aWVyQHRyaWxsaW 9uMDEuY29tPokCNwQTAQgAIQUCVh3TJwIbAwULCQgHAwUVCgkICwUWAgMBAAIeAQIXgAAKCRBlaka GGsWHEI1AD/9sbj+vnFU29WemVqB4iW+9RrHIcbXI4Jg8WaffTQ8KvVeCJ4otzgVT2nHC2A82t4PF 0tp21Ez17CKDNilMvOt8zq6ZHx36CPjoqUVjAdozOiBDpC4qB6ZKYn+gqSENO4hqmmaOW57wT9vII v6mtHmnFvgpOEJl6wbs8ArHDt0BLSjc8QQfvBhoKoWs+ijQTyvFGlQl0oWxEbUkR1J3gdft9Oj9xQ G4OFo73WaSEK/L9IalU2ulCBC+ucSP9McoDxy1i1u8HUDrV5wBY1zafc9zVBcMNH6+ZjxwQmZXqtz ATzB3RbSFHAdmvxl8q6MeS2yx7Atk0CXgW9z5k2KeuZhz5rVV5A+D19SSGzW11uYXsibZx/Wjr9xB KHB6U7qh5sRHaQS191NPonKcsXXAziR+vxwQTP7ZKfy+g5N/e6uivoUnQrl9uvUDDPXEpwVNSoVws Vn4tNyrGEdN11pHDbH5fSGzdpbY8+yczUoxMmsEQe/fpVwRBZUqafRn2TVUhV0qqzsUuQcTNw1zIZ JgvkqrHgd4ivd2b1bXBczmu/wMGpEnF6cWzSQDiwC1NF3i+gHCuD8IX1ujThWtzXsn0VtrMkrRCbn ponVQ6HcbRYYXPuK0HRRjCSuAKo5porVONepiOSmu0FBrpGqBkpBtLrzKXoi1yt/7a/wGdMcVhYGg vA== Organization: Trillion01 Inc Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.52.4 Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - cloud48395.mywhc.ca X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - trillion01.com X-Get-Message-Sender-Via: cloud48395.mywhc.ca: authenticated_id: olivier@trillion01.com X-Authenticated-Sender: cloud48395.mywhc.ca: olivier@trillion01.com X-Source: X-Source-Args: X-Source-Dir: On Tue, 2024-08-13 at 12:35 -0600, Jens Axboe wrote: > On 8/13/24 11:22 AM, Olivier Langlois wrote: > > On Mon, 2024-08-12 at 14:40 -0600, Jens Axboe wrote: > > >=20 > > >=20 > > > > 3. I am surprised to notice that in __io_napi_do_busy_loop(), > > > > list_for_each_entry_rcu() is called to traverse the list but > > > > the > > > > regular methods list_del() and list_add_tail() are called to > > > > update > > > > the > > > > list instead of their RCU variant. > > >=20 > > > Should all just use rcu variants. > > >=20 > > > Here's a mashup of the changes. Would be great if you can test - > > > I'll > > > do > > > some too, but always good with more than one person testing as it > > > tends > > > to hit more cases. > > >=20 > > Jens, > >=20 > > I have integrated our RCU corrections into > > https://lore.kernel.org/io-uring/5fc9dd07e48a7178f547ed1b2aaa0814607fa2= 46.1723567469.git.olivier@trillion01.com/T/#u > >=20 > > and my testing so far is not showing any problems... > > but I have a very static setup... > > I had no issues too without the corrections... >=20 > Thanks for testing, but regardless of whether that series would go in > or > not, I think those rcu changes should be done separately and upfront > rather than be integrated with other changes. >=20 sorry about that... I am going to share a little bit how I currently feel. I feel disappointed because when I reread your initial reply, I have not been able to spot a single positive thing said about my proposal despite that I have prealably tested the water concerning my idea and the big lines about how I was planning to design it. All, I have been told from Pavel that the idea was so great that he was even currently playing with a prototype around the same concept: https://lore.kernel.org/io-uring/1be64672f22be44fbe1540053427d978c0224dfc.c= amel@trillion01.com/T/#mc7271764641f9c810ea5438ed3dc0662fbc08cb6 you also have to understand that all the small napi issues that I have fixed this week are no stranger from me working on this new idea. The RCU issues that I have reported back have been spotted when I was doing my final code review before testing my patch before submitting it. keep in mind that I am by far a git magician. I am a very casual user... Anything that is outside the usual beaten trails such as reordoring commits or breaking them down feels perilious to me... I had 230+ lines changes committed when you confirmed that few lines should be changed to address this new RCU issue. I did figure that it would not that big a deal to include them with the rest of my change. that being said, if my patch submission is acceptable conditional to needed rework, I am willing to learn how to better use git to meet your requirements. Greetings,