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Subject: Re: Q: perf_install_in_context/perf_event_enable are racy?
From: Peter Zijlstra <peterz@infradead.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>, Ingo Molnar <mingo@elte.hu>,
        Alan Stern <stern@rowland.harvard.edu>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
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        Roland McGrath <roland@redhat.com>, linux-kernel@vger.kernel.org
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Date: Wed, 26 Jan 2011 20:38:03 +0100
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On Wed, 2011-01-26 at 20:33 +0100, Peter Zijlstra wrote:

> Wouldn't something like the below cure things too?

> +struct task_function_call {
> +	struct task_struct *p;
> +	void (*func)(void *info);
> +	void *info;
> +};
> +
> +void task_function_trampoline(void *data)
> +{
> +	struct task_function_call *tfc = data;
> +
> +	if (this_rq()->curr != tfc->p)
> +		return;
> +
> +	tfc->func(tfc->data);
> +}

tfc->info of course ;-)