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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Tue, 13 Feb 2024 09:32:26 -0800
Message-ID: <CAHk-=wjQ9BJKBPi3sJN2Dy5jVwPO03u9aOc6-g8AnLcGq-E4-g@mail.gmail.com>
Subject: Re: [GIT PULL] tracing/tooling: Fixes for v6.8-rc4
To: Steven Rostedt <rostedt@goodmis.org>, Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>, John Kacur <jkacur@redhat.com>, 
	limingming3 <limingming890315@gmail.com>, LKML <linux-kernel@vger.kernel.org>
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On Mon, 12 Feb 2024 at 14:00, Steven Rostedt <rostedt@goodmis.org> wrote:
>
> Tracing tooling updates for 6.8-rc4:

Bah. I've pulled this, but since I did a new system install due to a
disk upgrade some time ago, I once again don't have libtracefs-devel
installed.

And guess what? The dependency rules are - once again  - completely
broken, and trying to build this gets the bad old unhelpful error

   latency-collector.c:26:10: fatal error: tracefs.h: No such file or directory

with no help for the user.

Yes, I know what to do. That isn't the point. And no, this isn't new
to this pull request, it's just that on this machine I haven't tried
building the tracing tools in a while.

Let's not make the user experience for people who want to do kernel
builds any worse than it has to be.

Side note: instead of the (clearly broken) special Makefile rules, can
you please just take a look at the perf code instead?  In fact, maybe
it's time for the kernel tooling people to try to unify and come to an
agreement about these things, and share more of the code.

Because unlike the tracing tools, the perf tools seem to generally get
this part of the build system right, despite (or probably due to)
having a lot *more* (and more complex) library dependencies.

              Linus