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Date: Tue, 16 Nov 2010 23:08:51 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <dvhart@linux.intel.com>, Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>,
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        "David S. Miller" <davem@davemloft.net>,
        Christoph Hellwig <hch@lst.de>, Pekka Enberg <penberg@kernel.org>,
        Lai Jiangshan <laijs@cn.fujitsu.com>,
        Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [ANNOUNCE] New utility: 'trace'
Message-ID: <20101116220851.GA15052@elte.hu>
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* Peter Zijlstra <peterz@infradead.org> wrote:

> On Tue, 2010-11-16 at 22:59 +0100, Ingo Molnar wrote:
> > 
> > 
> > Would you be interested in helping out with (and testing) such a more generic 
> > approach?
> 
> how about having perf-record open a named pipe and rewriting everything that comes 
> in through that as an event and storing it in the buffer?

Yeah, that would work too in most cases - except if there's no VFS connection 
between tracer and tracee. (as it might be in the case of say chroot environments, 
etc.)

I think it's better to have kernel solutions that dont modify the VFS beyond the 
trace.data session info. A task could thus generate a user-space event without 
having to negotiate with the tracer.

Thanks,

	Ingo
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