Re: ib_post_send in drivers

[Jason Gunthorpe <jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>]

On Sat, Nov 21, 2009 at 12:17:32PM +0100, Bart Van Assche wrote:

> ib_post_send() has to request a completion notification for each WR,
> which has a negative performance impact. My opinion is that the
> current behavior makes ib_post_send() easier to implement, while the
> behavior specified in the IBAS is more interesting for applications
> that use the verbs API.

It seems to me an error return from ib_post_send either means the
caller is asking for something impossible, or the QP is wrecked, and
is thus pretty much non-recoverable. For instance all the errors for
mlx4 fit this pattern - and I think that is a reasonable requirement
for any implementation of ib_post_send.

So in that light the absence/presence of a completion does not seem
important - if you get an error back you should always tear down the
QP.

Are SRP/etc calling ib_post_send in a way that ever returns errors?

Jason
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