From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 995CC2139A2; Tue, 18 Jun 2024 12:11:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718712709; cv=none; b=U4YOgj5NdQjikdU1+dfMVsjL7C0DqEN0bLtxCQ/3QWJrzLZjpDi0dWiRlZxI/VAlWKLjPhlczVf6EvtviD5zSFMNPNoOd26ATegZBWFQKY5XiJ8bgOXVu50ZAE7LsWalfTKwlUM/uWc5EuWp7jvVJbdNtYsHHqFgy7stMKryii4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718712709; c=relaxed/simple; bh=VoZ4zhtJJmaHjupDiKoJdFBRS8zOfKvXjt5MM4X0JmI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Hxvxy78Mn031sGLNuIFxhqhlWwcxp0A5G4LXwvdkWOVXuPuodgOb9s2wGPs5JFchpqZJTtJ/s9NdUgNoMl/eLAAQq23HcaDqAq+l+3IY2FruNqZhXVEyD5uDvCW6MAUS/H9u428scDDqGj0xMMetB89u3rl4lhhyFwwtKfZJOrM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RBcsmtJs; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="RBcsmtJs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8991CC32786; Tue, 18 Jun 2024 12:11:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718712709; bh=VoZ4zhtJJmaHjupDiKoJdFBRS8zOfKvXjt5MM4X0JmI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=RBcsmtJsZer/gER0g2gI3eZ3i6X+NX8nSmwWQko+AxtcmGWL/tUaCZMNQ83dXDTxm El1xc+IIBTGw7fcVJsWaDsJFgbNknq8TRzqI7y94Y+2A3KTeAqeOlu77oBdRw3S7TA j6Efbqi+vUsc+qGlP13SNU0jhrZK7onuaJiCUCfUAO4z1xA/vDqadpPU1EPrsI3J5U RiqefzGbAGPpGCqHVc9twt3wRcwwtNRAQAUeRYCzlqS7nI1LD9Q8lLi1MD6Xee44dE 3Z6WNLHIMszKeEi7Z2ulT0rlw5f9YTXqMEV5WtHyRlXBG2xJ/cynTnVIUZnIr6gQ7t hXbl/A4rXrdgg== Date: Tue, 18 Jun 2024 14:11:44 +0200 From: Christian Brauner To: Linus Torvalds Cc: Mateusz Guzik , viro@zeniv.linux.org.uk, 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: <20240618-spotten-scheren-0c87d248419f@brauner> References: <5cixyyivolodhsru23y5gf5f6w6ov2zs5rbkxleljeu6qvc4gu@ivawdfkvus3p> <20240613-pumpen-durst-fdc20c301a08@brauner> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Thu, Jun 13, 2024 at 12:33:59PM GMT, Linus Torvalds wrote: > On Thu, 13 Jun 2024 at 11:56, Linus Torvalds > wrote: > > > > I didn't *think* anything in the dentry struct should care about > > debugging, but clearly that sequence number thing did. > > Looking at the 32-bit build, it looks like out current 'struct dentry' > is 136 bytes in size, not 128. > > Looks like DNAME_INLINE_LEN should be reduced to 36 on 32-bit. > > And moving d_lockref to after d_fsdata works there too. > > Not that anybody really cares, but let's make sure it's actually > properly done when this is changed. Christian? So I verified that indeed on i386 with CONFIG_SMP we need 36 to get to 128 bytes and yes, moving d_lockref after d_fsdata works. So I've put that patch on top. (Sorry, took a bit. I'm back tomorrow.)