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Date:   Wed, 31 Aug 2022 04:42:30 -0400
From:   Kent Overstreet <kent.overstreet@linux.dev>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Suren Baghdasaryan <surenb@google.com>, akpm@linux-foundation.org,
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Subject: Re: [RFC PATCH 00/30] Code tagging framework and applications
Message-ID: <20220831084230.3ti3vitrzhzsu3fs@moria.home.lan>
References: <20220830214919.53220-1-surenb@google.com>
 <Yw8P8xZ4zqu121xL@hirez.programming.kicks-ass.net>
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On Wed, Aug 31, 2022 at 09:38:27AM +0200, Peter Zijlstra wrote:
> On Tue, Aug 30, 2022 at 02:48:49PM -0700, Suren Baghdasaryan wrote:
> > ===========================
> > Code tagging framework
> > ===========================
> > Code tag is a structure identifying a specific location in the source code
> > which is generated at compile time and can be embedded in an application-
> > specific structure. Several applications of code tagging are included in
> > this RFC, such as memory allocation tracking, dynamic fault injection,
> > latency tracking and improved error code reporting.
> > Basically, it takes the old trick of "define a special elf section for
> > objects of a given type so that we can iterate over them at runtime" and
> > creates a proper library for it.
> 
> I might be super dense this morning, but what!? I've skimmed through the
> set and I don't think I get it.
> 
> What does this provide that ftrace/kprobes don't already allow?

You're kidding, right?