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[2604:1380:45d1:ec00::1]) by mx.google.com with ESMTPS id af79cd13be357-798abe5582fsi278349085a.569.2024.06.13.17.53.30 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 13 Jun 2024 17:53:30 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel+bounces-213866-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1; Authentication-Results: mx.google.com; dkim=pass header.i=@linux.org.uk header.s=zeniv-20220401 header.b=TRV4oeXJ; arc=pass (i=1 dkim=pass dkdomain=linux.org.uk dmarc=pass fromdomain=zeniv.linux.org.uk); spf=pass (google.com: domain of linux-kernel+bounces-213866-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) smtp.mailfrom="linux-kernel+bounces-213866-linux.lists.archive=gmail.com@vger.kernel.org"; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=zeniv.linux.org.uk Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ny.mirrors.kernel.org (Postfix) with ESMTPS id 017421C248F5 for ; Thu, 13 Jun 2024 18:56:09 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id F41E914C5BF; Thu, 13 Jun 2024 18:55:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b="TRV4oeXJ" Received: from zeniv.linux.org.uk (zeniv.linux.org.uk [62.89.141.173]) (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 DFB8584A48; Thu, 13 Jun 2024 18:55:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.89.141.173 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718304953; cv=none; b=Ox7+A7wzfJtMF3qchNxRvd8XO8fPvvyFgUvdZfHWr7PreicDxlIvXmT5QuL7wBvAiVU0TZDKdOEoG+Jh6SMu96HcLHHgsNs2VlWdXzqwJDg2tHfsdSfNNKMVQzJ3Ybs0sby6Nb1kiOIb0Ca+vPzqK132Q3/VXGFVyzQZVIm+L88= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718304953; c=relaxed/simple; bh=63ugLzPkZISDkE/R2ja4qO6bJ89KfrEGKAD4KlJR1D8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Et1CEzyt9lqbwZjFLr9YEO38VFEktfS5t74bC69U07sYgjULgGF62cWUIJaQJuKr3N5RCWWPfs9sSToGFgHOJeOaAUUEG5F+ZP8clKZpICdSmEkegIMMIs0oiHC1V5KHBp42RDzNGjm+KF5co0kPhNZcB77zUVXrZM/dJcZNT0c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk; spf=none smtp.mailfrom=ftp.linux.org.uk; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b=TRV4oeXJ; arc=none smtp.client-ip=62.89.141.173 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=ftp.linux.org.uk DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=linux.org.uk; s=zeniv-20220401; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=AY43+HBOJx3kLbSrEpkOfh/9TQVZmcpW+OF54BWBDDQ=; b=TRV4oeXJcTNJAIbe6ATskhY2ag C8V5GUmUSmL8RPcf+68GRFJbhJgOwqhTkDQ+PIESxdG5atvY47szMRa/KEID9XEVHKcrGO9QCtK+D 1eg+90U83W2ORq0rqJyKKeHMKBcGbcnWOGWdFy6LusE8sGW0vZaFy+zLOkBH/Rm8errXpNAyh+JHr rDex33PIa/Gq6orzytnoXse3Jrjq5rslmD+Hhocsb2JyuuvVbp+MDX5Ua2M/zHjBVUFlhEdQVo4DY k7dXy2F7xSRwEjEjhE8xkjyLeLG2lHRICSRKHn/0VyoNRL7nkCH/IGcO2vVLqUklF+bgRQI75nizR v3pehW9Q==; Received: from viro by zeniv.linux.org.uk with local (Exim 4.96 #2 (Red Hat Linux)) id 1sHpbt-00336k-0s; Thu, 13 Jun 2024 18:55:45 +0000 Date: Thu, 13 Jun 2024 19:55:45 +0100 From: Al Viro To: Linus Torvalds Cc: Mateusz Guzik , Christian Brauner , jack@suse.cz, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH 1/2] lockref: speculatively spin waiting for the lock to be released Message-ID: <20240613185545.GI1629371@ZenIV> References: <20240613001215.648829-1-mjguzik@gmail.com> <20240613001215.648829-2-mjguzik@gmail.com> <5cixyyivolodhsru23y5gf5f6w6ov2zs5rbkxleljeu6qvc4gu@ivawdfkvus3p> <20240613-pumpen-durst-fdc20c301a08@brauner> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: Al Viro On Thu, Jun 13, 2024 at 11:43:05AM -0700, Linus Torvalds wrote: > seqcount_spinlock_t d_seq; > > because seqcount_spinlock_t has been entirely broken and went from > being 4 bytes back when, to now being 64 bytes. 1ca7d67cf5d5 "seqcount: Add lockdep functionality to seqcount/seqlock structures"