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 7AEADC433FE for ; Mon, 21 Nov 2022 17:10:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229721AbiKURKK (ORCPT ); Mon, 21 Nov 2022 12:10:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60496 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229586AbiKURKJ (ORCPT ); Mon, 21 Nov 2022 12:10:09 -0500 Received: from mail-il1-x134.google.com (mail-il1-x134.google.com [IPv6:2607:f8b0:4864:20::134]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 336F5DED0 for ; Mon, 21 Nov 2022 09:10:09 -0800 (PST) Received: by mail-il1-x134.google.com with SMTP id x13so2642891ilp.8 for ; Mon, 21 Nov 2022 09:10:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:mime-version:date:message-id:subject :references:in-reply-to:to:from:from:to:cc:subject:date:message-id :reply-to; bh=EtkWtcbaJkBmtGU/sjvsDJMEYXWMEHtOYjWjLql/jWM=; b=u6ToD3K3HLr55Fbq2ZXMTEjJ8SI6oftuawXhN0txHczgJ5WrclEks6mjqNgtmvdKlW +/Z4Q4bTIKHYV/fopN124P4hSUd7gloi9W+DBe3/looaRetKHQhaik0YXD495IzeYjDT OPaLi+GQrsdlKVaWjiIiXvGsplurb/F5bPQK41uoDRjuUhl5xmOLZe6VTltd+zY12JBS Y5mw2cOoudnoYEcdf1c/4TONiORWUR7TtgM0dv3UvxJWKECVPIh9vqv9eq2DoQptfnPi THgem2JoHOtFOLCmrf6oPbM9HWFKhXWQx7LcTi7ZzSouJShftc5Qz1jAjCHD78XcUwLR ttzg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:date:message-id:subject :references:in-reply-to:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=EtkWtcbaJkBmtGU/sjvsDJMEYXWMEHtOYjWjLql/jWM=; b=Y/Bo0TUxKle4KLUJRrKbHYZj3LXN/LA+Ml78aPtMsmUPgc4NHk7XAaeAtVewItWCNf MhrLKZnS/EBkMJBLzQxMADjyUpuLGZMlzfuWjtjHT33uBo+JhrQg9gUjIq63FL0pglG9 QPHsgqh2synqAp/UTd/6z34EwiSVYTsiOvzTyRKixm2uiacdkEZgsiVEYUt23jsMc1bx t2+scOOG/yoIP/tdJtj+Srh1kFxu4Z90ynR86wvFKHU+K8ap8acNfrMsZ6ohRiGhXSl3 /oJozAJH5Wee7sVRsOAh6vTjIPpAnJSodIr4QnR1BILIca69+PLWop4j2iDBJRQElIpe bjzA== X-Gm-Message-State: ANoB5pkT/besM/Tb0BoN3vToQgZTEF6XiBVB3gvpvpYaWAy9XjlWTSUy 3xoFUS5CDHvtuqUe19cO07o382SKrjJ6tQ== X-Google-Smtp-Source: AA0mqf4cb2uK7GeXDDGUND89K6QVwZwgZLU7lN7UBQDMLHHHYlo8vg2f1rqXaKSs4w8hyyeYaTLy/g== X-Received: by 2002:a05:6e02:1210:b0:2f9:aecd:6397 with SMTP id a16-20020a056e02121000b002f9aecd6397mr8680225ilq.100.1669050608247; Mon, 21 Nov 2022 09:10:08 -0800 (PST) Received: from [127.0.0.1] ([207.135.234.126]) by smtp.gmail.com with ESMTPSA id f9-20020a056e0204c900b002f916f15625sm4056414ils.23.2022.11.21.09.10.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Nov 2022 09:10:07 -0800 (PST) From: Jens Axboe To: Pavel Begunkov , io-uring@vger.kernel.org In-Reply-To: References: Subject: Re: [PATCH v3 0/2] poll_refs armoring Message-Id: <166905060765.3007.1682250454703276983.b4-ty@kernel.dk> Date: Mon, 21 Nov 2022 10:10:07 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit X-Mailer: b4 0.11.0-dev-28747 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Sun, 20 Nov 2022 16:57:40 +0000, Pavel Begunkov wrote: > Make poll_refs more robust and protected from overflows. The mechanism > description is in 2/2. 1/2 helps to make the second patch a little bit > cleaner by tunnelling all edge cases from arming to a tw. > > A good way to test is to set IO_POLL_REF_BIAS to 0 and 1. 0 will make > the slowpath to be hit every single time, and 1 triggers it in case of > races. > > [...] Applied, thanks! [1/2] io_uring: cmpxchg for poll arm refs release (no commit info) [2/2] io_uring: make poll refs more robust (no commit info) Best regards, -- Jens Axboe