Date: Thu, 9 Apr 2015 10:01:23 -0600
From: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
To: Doug Ledford <dledford@redhat.com>
Cc: Michael Wang <yun.wang@profitbricks.com>,
        Roland Dreier <roland@kernel.org>, Sean Hefty <sean.hefty@intel.com>,
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        Hal Rosenstock <hal.rosenstock@gmail.com>,
        Tom Tucker <tom@opengridcomputing.com>,
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        Hoang-Nam Nguyen <hnguyen@de.ibm.com>,
        Christoph Raisch <raisch@de.ibm.com>,
        Mike Marciniszyn <infinipath@intel.com>, Eli Cohen <eli@mellanox.com>,
        Faisal Latif <faisal.latif@intel.com>,
        Upinder Malhi <umalhi@cisco.com>,
        Trond Myklebust <trond.myklebust@primarydata.com>,
        "J. Bruce Fields" <bfields@fieldses.org>,
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        Tom Gundersen <teg@jklm.no>, Chuck Lever <chuck.lever@oracle.com>
Subject: Re: [PATCH v2 01/17] IB/Verbs: Implement new callback
 query_transport() for each HW
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On Thu, Apr 09, 2015 at 10:34:30AM -0400, Doug Ledford wrote:

> These are exactly the tests I proposed Jason.  I'm not sure I see your
> point here.  I guess my point is that although the scenario of all the
> different items seems complex, it really does boil down to needing only
> exactly what I proposed earlier to fulfill the entire test matrix.

I have no problem with minimizing a bitmap, but I want the accessors
to make sense first.

My specific problem with your suggestion was combining cap_ib_mad,
cap_ib_sa, and cap_ib_smi into rdma_port_ib_fabric_mgmt.

Not only do the three cap things not return the same value for all
situations, the documentary knowledge is lost by the reduction.

I'd prefer we look at this from a 'what do the call sites need' view,
not a 'how do we minimize' view.

I've written this before: The mess here is that it is too hard to know
what the call sites are actually checking for when it is some baroque
conditional.

Jason