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 6FB041841 for ; Wed, 1 Nov 2023 04:17:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: by smtp.kernel.org (Postfix) with ESMTPSA id 269C5C433C8; Wed, 1 Nov 2023 04:17:01 +0000 (UTC) Date: Wed, 1 Nov 2023 00:16:59 -0400 From: Steven Rostedt To: Al Viro Cc: LKML , Linux Trace Kernel , Masami Hiramatsu , Mark Rutland , Ajay Kaher Subject: Re: [PATCH] eventfs: Process deletion of dentry more thoroughly Message-ID: <20231101001659.1456b3d4@gandalf.local.home> In-Reply-To: <20231101022553.GE1957730@ZenIV> References: <20231031144703.71eef3a0@gandalf.local.home> <20231101022553.GE1957730@ZenIV> X-Mailer: Claws Mail 3.19.1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Wed, 1 Nov 2023 02:25:53 +0000 Al Viro wrote: > On Tue, Oct 31, 2023 at 02:47:03PM -0400, Steven Rostedt wrote: > > From: "Steven Rostedt (Google)" > > > > Looking at how dentry is removed via the tracefs system, I found that > > eventfs does not do everything that it did under tracefs. The tracefs > > removal of a dentry calls simple_recursive_removal() that does a lot more > > than a simple d_invalidate(). > > Umm... Is there any reason not to use simple_recursive_removal() there? Hmm, I may be able to (I'm still a newbie with understanding of the vfs). I did it this way thinking that a dentry may exist in the children but not at a higher level, but I don't think that can be the case. This creates dentries and inodes dynamically when they are referenced. The eventfs_inode maps to each directory (the files of a directory are created from the information from the eventfs_inode). My thought process for doing it this way was if a child created a dentry but the parent did not. But I don't think that can happen, right? So all I may need to do is to check if the ei->dentry exists for the ei that is being deleted, and after marking it and all its children as "freed", I can then call simple_recursive_removal() on the top ei->dentry if it exists, as that will guarantee to get all the dentries of any of the children that exist. Right? -- Steve