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Date: Thu, 14 Jan 2010 10:03:27 -0800
Message-ID: <bc915a051001141003s766689beue73800a1308d957e@mail.gmail.com>
Subject: Re: HW breakpoints perf_events request
From: Joshua Pincus <joshua.pincus@gmail.com>
To: Andi Kleen <andi@firstfloor.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
       "K.Prasad" <prasad@linux.vnet.ibm.com>, peterz@infradead.org,
       paulus@samba.org, acme@redhat.com, linux-kernel@vger.kernel.org
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Hi,

On Thu, Jan 14, 2010 at 1:23 AM, Andi Kleen <andi@firstfloor.org> wrote:
>> We would like to avoid using ptrace at all costs.
>> It requires us to have a parent thread running
>> which monitors all the others.  It's not clear that
>> the wait() call by the parent doesn't mask a barrage
>> of signals from various threads and the performance
>
> mask? It'll report them. You expect to have so
> many signals that this would be a problem?

Yes.  We expect to see a zillion of them.

> -Andi
>

Thanks,
JP