Re: kernel memory registration

2015-07-14 Thread Sagi Grimberg
Having a few schemes availabe in the core code that the driver can chose from seems like a much more sensible option. I think that makes sense, but several of the schemes we are working with are effectively single-vendor schemes. Indirect MR and DIX are good examples of things that only one

Re: kernel memory registration

2015-07-14 Thread Jason Gunthorpe
On Tue, Jul 14, 2015 at 11:24:26AM +0300, Sagi Grimberg wrote: Having a few schemes availabe in the core code that the driver can chose from seems like a much more sensible option. I think that makes sense, but several of the schemes we are working with are effectively single-vendor

Re: kernel memory registration (was: RDMA/core: Transport-independent access flags)

2015-07-13 Thread Jason Gunthorpe
On Sat, Jul 11, 2015 at 03:31:53AM -0700, 'Christoph Hellwig' wrote: I'm not too excited about moving the code in the drivers. The RDMA subsystem actually has a lot more hardware drivers than ULDs, so moving logic into them seems like a major step backwards. From my journeys into the drivers

Re: kernel memory registration (was: RDMA/core: Transport-independent access flags)

2015-07-11 Thread 'Christoph Hellwig'
On Fri, Jul 10, 2015 at 11:55:29AM +0300, Sagi Grimberg wrote: If there is one thing worse than a complicated API, it is a restrictive one. I'd much rather ULPs just having a simple API for registering memory. Quite to the contrary. The complex API almost asks for weird abuses and twists.

kernel memory registration (was: RDMA/core: Transport-independent access flags)

2015-07-10 Thread Sagi Grimberg
On 7/9/2015 8:01 PM, Jason Gunthorpe wrote: On Thu, Jul 09, 2015 at 02:02:03PM +0300, Sagi Grimberg wrote: We have protocol that involves remote memory keys transfer in their standards so I don't see how we can remove it altogether from ULPs. This is why I've been talking about local and

Re: kernel memory registration (was: RDMA/core: Transport-independent access flags)

2015-07-10 Thread Jason Gunthorpe
On Fri, Jul 10, 2015 at 11:55:29AM +0300, Sagi Grimberg wrote: IMHO, memory registration is memory registration. The fact that we are distinguishing between local and remote might be a sign that this might be a wrong direction to take. Sorry. I belive they are very different, yes, if you sit