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Date: Mon, 23 Feb 2009 18:37:14 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Steven Rostedt <rostedt@goodmis.org>,
       Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
       LKML <linux-kernel@vger.kernel.org>,
       Arnaldo Carvalho de Melo <acme@redhat.com>
Subject: Re: [PATCH] tracing/ftrace: add missing wake-up on some callsites
Message-ID: <20090223173714.GA601@elte.hu>
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* Steven Rostedt <rostedt@goodmis.org> wrote:

> > Which would send a delayed work to wake up?
> 
> No, I was thinking that trace_delay_wake_up() would be called 
> by these dangerous call sites. Then a per_cpu flag could be 
> set. We could have a trace point in the scheduler code that is 
> outside holding a runqueue lock, and this trace point would 
> call a trace function that will clear the per cpu flag, and 
> then call trace_wake_up().

No, that's very roundabout and ugly. If we putting a tracepoint 
there we might as well put real scheduler code there that looks 
for such a flag. But i'm not convinced we need a flag ...

	Ingo