RE: [PATCH V5 5/5] RDMA/isert: Limit read depth based on the device max_sge_rd capability

Steve Wise
2015-07-14T19:11:58Z

> -----Original Message-----
> From: linux-rdma-owner@vger.kernel.org [mailto:linux-rdma-owner@vger.kernel.org] On Behalf Of Chuck Lever
> Sent: Tuesday, July 14, 2015 1:47 PM
> To: Steve Wise
> Cc: Christoph Hellwig; Doug Ledford; infinipath@intel.com; Sagi Grimberg; Or Gerlitz; roid@mellanox.com; linux-rdma; Eli Cohen;
target-
> devel@vger.kernel.org
> Subject: Re: [PATCH V5 5/5] RDMA/isert: Limit read depth based on the device max_sge_rd capability
>
>
> On Jul 14, 2015, at 11:49 AM, Steve Wise <swise@opengridcomputing.com> wrote:
>
> >
> >
> >> -----Original Message-----
> >> From: 'Christoph Hellwig' [mailto:hch@infradead.org]
> >> Sent: Tuesday, July 14, 2015 10:42 AM
> >> To: Steve Wise
> >> Cc: 'Christoph Hellwig'; Chuck Lever; dledford@redhat.com; infinipath@intel.com; sagig@mellanox.com; ogerlitz@mellanox.com;
> >> roid@mellanox.com; linux-rdma@vger.kernel.org; eli@mellanox.com; target-devel@vger.kernel.org
> >> Subject: Re: [PATCH V5 5/5] RDMA/isert: Limit read depth based on the device max_sge_rd capability
> >>
> >> On Tue, Jul 14, 2015 at 09:41:00AM -0500, Steve Wise wrote:
> >>>> Btw, any hance to make the NFS client use these values as well instead
> >>>> of the current rdma_read_max_sge() hack?
> >>>
> >>> Chuck, can you add this to your cleanup list?
> >>
> >> It would be useful to add this to your series so we can get rid of
> >> it for the next merge window instead of introducing a depenency that
> >> would defer it to the next merge window.
> >
> > Ok, I will do this.
>
> Steve, can you review v2 of the nfs-rdma-for-4.3 series I posted
> yesterday? Specifically:
>
> http://git.linux-nfs.org/?p=cel/cel-2.6.git;a=commit;h=6abafb636e03fbb7f93a26796223833581a70190
>
> Which changes the way xprtrdma uses max_sge.
>

Sure, but xprtrdma doesn't issue reads, so max_sge_rd isn't needed. The change Christoph wants is actually in svcrdma. I will
change the server to use max_sge_rd instead of rdma_cap_read_multi_sge().