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To: Heiko J Schick <schihei@de.ibm.com>
Subject: Re: [openib-general] [PATCH 07/16] ehca: interrupt handling routines
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From: Roland Dreier <rdreier@cisco.com>
Date: Tue, 09 May 2006 09:23:38 -0700
In-Reply-To: <44608C90.30909@de.ibm.com> (Heiko J. Schick's message of "Tue,
	09 May 2006 14:35:28 +0200")
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Cc: linux-kernel@vger.kernel.org, openib-general@openib.org,
	linuxppc-dev@ozlabs.org, Christoph Raisch <RAISCH@de.ibm.com>,
	Hoang-Nam Nguyen <HNGUYEN@de.ibm.com>, Marcus Eder <MEDER@de.ibm.com>
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    Heiko> Yes, I agree. It would not be an optimal solution, because
    Heiko> other upper level protocols (e.g. SDP, SRP, etc.) or
    Heiko> userspace verbs would not be affected by this
    Heiko> changes. Nevertheless, how can an improved "scaling" or
    Heiko> "SMP" version of IPoIB look like. How could it be
    Heiko> implemented?

The trivial way to do it would be to use the same idea as the current
ehca driver: just create a thread for receive CQ events and a thread
for send CQ events, and defer CQ polling into those two threads.

Something even better may be possible by specializing to IPoIB of course.

 - R.