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Date: Wed, 20 Oct 2010 20:40:32 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Jason Baron <jbaron@redhat.com>, LKML <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Arnaldo Carvalho de Melo <acme@redhat.com>
Subject: Re: [PATCH][GIT PULL] tracing: Fix compile issue for
 trace_sched_wakeup.c
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* Steven Rostedt <rostedt@goodmis.org> wrote:

> jump_label_update uses stop_machine to enable each tracepoint. Thus this is 
> stressing stop machine.
> 
> Does this only happen on i386, or do we get this on x86_64 too?

I've only seen it on 32-bit - and this testbox is booting both random 64-bit and 
32-bit kernels, so the test proportion is 50%.

The failures started at around the time Thomas did the big irq/core changes a couple 
of days ago. I first blamed it on him. I.e. it's around:

  12ef49d: Merge branch 'irq/core'

That's right after jump labels and some other tracing changes went in. The compiler 
i'm using is:

  gcc version 4.4.4 20100514 (Red Hat 4.4.4-3) (GCC) 

which doesnt support jump labels.

	Ingo