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Subject: Re: [RFC][PATCH 6/7] perf: use jump_label to optimize the
 scheduler hooks
From: Peter Zijlstra <peterz@infradead.org>
To: Ingo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>, Jason Baron <jbaron@redhat.com>,
        linux-kernel@vger.kernel.org, David Miller <davem@davemloft.net>,
        Mike Galbraith <efault@gmx.de>
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	 <20101014203625.552405859@chello.nl>
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Date: Sun, 17 Oct 2010 11:52:39 +0200
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On Thu, 2010-10-14 at 22:34 +0200, Peter Zijlstra wrote:
> +static inline void perf_event_task_sched_in(struct task_struct *task)
> +{
> +       JUMP_LABEL(&perf_task_events, have_events);
> +       return;
> +
> +have_events:
> +       __perf_event_task_sched_in(task);
> +} 

OK, so I hate the JUMP_LABEL() interface for it means we have to keep
writing these silly stubs.

How about something like:

#define COND_STMT(key, stmt)					\
do {								\
	__label__ jl_enabled;					\
	JUMP_LABEL(key, jl_enabled);				\
	if (0) {						\
jl_enabled:							\
		stmt;						\
	}							\
} while (0)