Messages in this thread | | | Subject | Re: [PATCH rdma-next 00/10] Enable relaxed ordering for ULPs | From | Tom Talpey <> | Date | Wed, 14 Apr 2021 10:16:28 -0400 |
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On 4/12/2021 6:48 PM, Jason Gunthorpe wrote: > On Mon, Apr 12, 2021 at 04:20:47PM -0400, Tom Talpey wrote: > >> So the issue is only in testing all the providers and platforms, >> to be sure this new behavior isn't tickling anything that went >> unnoticed all along, because no RDMA provider ever issued RO. > > The mlx5 ethernet driver has run in RO mode for a long time, and it > operates in basically the same way as RDMA. The issues with Haswell > have been worked out there already. > > The only open question is if the ULPs have errors in their > implementation, which I don't think we can find out until we apply > this series and people start running their tests aggressively.
I agree that the core RO support should go in. But turning it on by default for a ULP should be the decision of each ULP maintainer. It's a huge risk to shift all the storage drivers overnight. How do you propose to ensure the aggressive testing happens?
One thing that worries me is the patch02 on-by-default for the dma_lkey. There's no way for a ULP to prevent IB_ACCESS_RELAXED_ORDERING from being set in __ib_alloc_pd().
Tom.
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