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Date: Thu, 16 Jan 2025 16:53:21 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: Theodore Ts'o <tytso@mit.edu>
Cc: lsf-pc@lists.linux-foundation.org,
	Linux Filesystem Development List <linux-fsdevel@vger.kernel.org>,
	bpf@vger.kernel.org
Subject: Re: [LSF/MM/BPF TOPIC] time to reconsider tracepoints in the vfs?
Message-ID: <20250116165321.GH1977892@ZenIV>
References: <20250116124949.GA2446417@mit.edu>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Thu, Jan 16, 2025 at 07:49:49AM -0500, Theodore Ts'o wrote:

> Secondly, we've had a very long time to let the dentry interface
> mature, and so (a) the fundamental architecture of the dcache hasn't
> been changing as much in the past few years, and (b) we should have
> enough understanding of the interface to understand where we could put
> tracepoints (e.g., close to the syscall interface) which would make it
> much less likely that there would be any need to make
> backwards-incompatible changes to tracepoints.

FWIW, earlier this week I'd been going through the piles of tracepoints
playing with ->d_name.  Mature interface or not, they do manage to
fuck that up...