From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Masami Hiramatsu <mhiramat@kernel.org>,
linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org
Subject: Re: [PATCH 6/6] eventfs: clean up dentry ops and add revalidate function
Date: Thu, 1 Feb 2024 08:07:15 +0900 [thread overview]
Message-ID: <20240201080715.80fadd15f38396c95bf39a00@kernel.org> (raw)
In-Reply-To: <20240131130039.241c8978@gandalf.local.home>
On Wed, 31 Jan 2024 13:00:39 -0500
Steven Rostedt <rostedt@goodmis.org> wrote:
> On Tue, 30 Jan 2024 11:03:55 -0800
> Linus Torvalds <torvalds@linux-foundation.org> wrote:
>
> > It would probably be cleaner to make eventfs its own filesystem, or at
> > least set its own dentry ops when looking up eventfs files. But as it
> > is, only eventfs dentries use d_fsdata, so we don't really need to split
> > these things up by use.
>
> BTW, I have been thinking about making eventfs a completely separate file
> system that could be mounted outside of tracefs. One that is readonly that
> only contains the "id" and "format" files and nothing more.
>
> Why? Because perf and powertop both use those files to know how to parse
> the raw event formats. I don't think there's anything in there that
> requires root privileges to read. They should not be exposing any internal
> kernel information besides the event format layouts, and it would be nice
> to have a /sys/kernel/events directory that only had that.
That's a good idea! So maybe we can allow perf to read it without root user.
>
> Making eventfs a separate file system where, when added to tracefs, has the
> control files for the specific trace_array, but for the /sys/kernel
> directory, only cares about the trace format files.
>
> Then tracefs could be nicely converted over to kernfs, and eventfs would be
> its own entity.
If so, maybe we can just make symlinks to the 'id' and 'format' from events
under tracefs? :)
Thank you,
>
> -- Steve
--
Masami Hiramatsu (Google) <mhiramat@kernel.org>
next prev parent reply other threads:[~2024-01-31 23:07 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-01-30 19:03 [PATCH 1/6] tracefs: avoid using the ei->dentry pointer unnecessarily Linus Torvalds
2024-01-30 19:03 ` [PATCH 2/6] eventfsfs: initialize the tracefs inode properly Linus Torvalds
2024-01-30 19:48 ` Steven Rostedt
2024-01-30 19:56 ` Steven Rostedt
2024-01-30 19:49 ` Steven Rostedt
2024-01-30 19:03 ` [PATCH 3/6] tracefs: dentry lookup crapectomy Linus Torvalds
2024-01-30 23:26 ` Al Viro
2024-01-30 23:55 ` Steven Rostedt
2024-01-31 0:07 ` Al Viro
2024-01-31 0:23 ` Al Viro
2024-01-31 0:39 ` Linus Torvalds
2024-01-30 19:03 ` [PATCH 4/6] eventfs: remove unused 'd_parent' pointer field Linus Torvalds
2024-01-30 19:03 ` [PATCH 5/6] eventfs: get rid of dentry pointers without refcounts Linus Torvalds
2024-01-30 20:55 ` Steven Rostedt
2024-01-30 21:52 ` Linus Torvalds
2024-01-30 22:56 ` Steven Rostedt
2024-01-30 22:58 ` Linus Torvalds
2024-01-30 23:04 ` Steven Rostedt
2024-01-30 22:56 ` Linus Torvalds
2024-01-30 23:06 ` Linus Torvalds
2024-01-30 23:10 ` Steven Rostedt
2024-01-30 23:25 ` Linus Torvalds
2024-01-31 0:48 ` Al Viro
2024-01-31 5:09 ` Steven Rostedt
2024-01-31 5:25 ` Linus Torvalds
2024-01-31 5:33 ` Steven Rostedt
2024-01-31 5:57 ` Linus Torvalds
2024-01-31 6:20 ` Linus Torvalds
2024-01-31 12:57 ` Steven Rostedt
2024-01-31 13:14 ` Steven Rostedt
2024-01-31 18:08 ` Linus Torvalds
2024-01-31 18:39 ` Steven Rostedt
2024-01-30 19:03 ` [PATCH 6/6] eventfs: clean up dentry ops and add revalidate function Linus Torvalds
2024-01-30 21:25 ` Steven Rostedt
2024-01-30 21:36 ` Linus Torvalds
2024-01-31 1:12 ` Al Viro
2024-01-31 2:37 ` Linus Torvalds
2024-01-31 2:46 ` Al Viro
2024-01-31 3:39 ` Linus Torvalds
2024-01-31 4:28 ` Al Viro
2024-01-31 18:00 ` Steven Rostedt
2024-01-31 23:07 ` Masami Hiramatsu [this message]
2024-01-31 23:23 ` Steven Rostedt
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