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 9C2AC537E4 for ; Wed, 17 Apr 2024 05:55:24 +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=1713333324; cv=none; b=p7suKGCHaWYeXbvqkjEJO5wiqnF/i2x+FL8rq51VBB5YsWnF8/cIA8Pp0fdaCQvaeDjrp6iWVx+gjarRhdO+dghgxGD+n4TVmErGQzTG5gSjTY0MzXmcD/LXtkUu6KXoQDFTR53RBlfdmvyKRaFY7sYdc42OM67eGka5zrEOBqE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713333324; c=relaxed/simple; bh=d25SWi9fRD0IJiGbi5USkQLSnRSyPWSSK3DzO9n0l9M=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=OoRUmlZU3ql9WAyKDOfAYXsRFoZflLbPRurzDFIq0fQrTMsUDaq05FFSgdw6Zf/OtnlHi7AOjdMS6iFb8qOn9H1sfhnFoHghTBAD5CX1xwoecsqW4h6nIZY2oIRTW+LRSvd5vk0MPgcgduughrJgzgw3qbr7xn0Aicjg28yjxsc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QfAzklOj; 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="QfAzklOj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1937FC072AA; Wed, 17 Apr 2024 05:55:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1713333324; bh=d25SWi9fRD0IJiGbi5USkQLSnRSyPWSSK3DzO9n0l9M=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=QfAzklOjXdQDa099aotM1oz79wjKSiCYjPvFVyC4OvD21sQEEHZuuaSEzXIJK/LRi Mm4qsRXwcPLJtNfok1wSamk349502OP6bCacsjx3AQMqsPGOl7DVrxJxdEGwKyDAvI 5lIX2hbbFe8YBUsd9woV6EjOS68eoEeGDIy/IkvyhDy5R1lp76VN4cTLd8d7Q6fWqF ZuKSJ9s8+V5sSHOe22sL7xBLee/MDm8TtBNIexKB/KQkMO0aH+/72SNz6bN/0EzRWD WdTdbLTX5T+K+j2uDSBudv4wITCs23sTwg08LlStYuvqcL+/CthVxWBDZJekxYAkEE KEIOjA/psaFHA== Date: Tue, 16 Apr 2024 22:55:23 -0700 From: "Darrick J. Wong" To: Christoph Hellwig Cc: Allison Henderson , catherine.hoang@oracle.com, linux-xfs@vger.kernel.org Subject: Re: [PATCH 27/32] xfs: Add parent pointer ioctls Message-ID: <20240417055523.GQ11948@frogsfrogsfrogs> References: <20240415194036.GD11948@frogsfrogsfrogs> <20240416044716.GA23062@lst.de> <20240416165056.GO11948@frogsfrogsfrogs> <20240416185209.GZ11948@frogsfrogsfrogs> <20240416190733.GC11948@frogsfrogsfrogs> <20240417052245.GP11948@frogsfrogsfrogs> <20240417052918.GA29248@lst.de> Precedence: bulk X-Mailing-List: linux-xfs@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: <20240417052918.GA29248@lst.de> On Wed, Apr 17, 2024 at 07:29:18AM +0200, Christoph Hellwig wrote: > On Tue, Apr 16, 2024 at 10:22:45PM -0700, Darrick J. Wong wrote: > > On Tue, Apr 16, 2024 at 12:14:24PM -0700, Christoph Hellwig wrote: > > > On Tue, Apr 16, 2024 at 12:07:33PM -0700, Darrick J. Wong wrote: > > > > Ohhhh, does that happens outside of XFS then? No wonder I couldn't find > > > > what you were talking about. Ok I'll go look some more. > > > > > > Yes. get_name() in fs/exportfs/expfs.c. > > > > Hmm. Implementing a custom ->get_name for pptrs would work well for > > child files with low hardlink counts. Certainly there are probably a > > lot more large directories than files that are hardlinked many many > > times. At what point does it become cheaper to scan the directory? > > Note that despite my previous confusion get_name is also called for > directories to find the actual name they have in their parent. > > An easy conservative choice would be to always look at the parent > pointers for nlink==1. > > All of that is for later, I don't want to delay the parent pointers > series even further. It won't; I'll need to test the default ->get_name implementation so that I can compare it to the new one, which means I'll have to figure out /how/ to test that. --D