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Date: Mon, 15 Jul 2024 18:30:03 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Kyle Huey <me@kylehuey.com>
Cc: Jiri Olsa <olsajiri@gmail.com>, khuey@kylehuey.com,
	Ingo Molnar <mingo@redhat.com>, Namhyung Kim <namhyung@kernel.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	robert@ocallahan.org, Joe Damato <jdamato@fastly.com>,
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	"Liang, Kan" <kan.liang@linux.intel.com>,
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	linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org,
	bpf@vger.kernel.org
Subject: Re: [PATCH] perf/bpf: Don't call bpf_overflow_handler() for tracing
 events
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On Mon, Jul 15, 2024 at 08:19:44AM -0700, Kyle Huey wrote:

> I think this would probably work but stealing the bit seems far more
> complicated than just gating on perf_event_is_tracing().

perf_event_is_tracing() is something like 3 branches. It is not a simple
conditional. Combined with that re-load and the wrong return value, this
all wants a cleanup.

Using that LSB works, it's just that the code aint pretty.