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Date:   Tue, 11 Jul 2023 14:34:33 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Zehao Zhang <zhangzehao@vivo.com>
Cc:     linkinjeon@kernel.org, sj1557.seo@samsung.com, rostedt@goodmis.org,
        mhiramat@kernel.org, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-trace-kernel@vger.kernel.org
Subject: Re: [PATCH v2] exfat: Add ftrace support for exfat and add some
 tracepoints
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On Tue, Jul 11, 2023 at 08:22:08PM +0800, Zehao Zhang wrote:
> Add ftrace support for exFAT file system,
> and add some tracepoints:

Why?  I don't believe these are useful.  Because if you actually had use
for them, you would have noticed that you're missing 99% of the reads
issued to the filesystem from the VFS -- through exfat_readahead(),
which you didn't instrument.

So what do you actually want to know, and why can't you get that
information already?