lkml.org 
[lkml]   [2022]   [Oct]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [RFC PATCH 0/3] new subsystem for compute accelerator devices
On Tue, Oct 25, 2022 at 7:15 AM Jason Gunthorpe <jgg@nvidia.com> wrote:
>
> On Tue, Oct 25, 2022 at 12:27:11PM +1000, Dave Airlie wrote:
>
> > The userspace for those is normally bespoke like ROCm, which uses
> > amdkfd, and amdkfd doesn't operate like most device files from what I
> > know, so I'm not sure we'd want it to operate as an accel device.
>
> I intensely dislike this direction that drivers will create their own
> char devs buried inside their device driver with no support or
> supervision.
>
> We've been here before with RDMA and it is just a complete mess.
>
> Whatever special non-drm stuff amdkfd need to do should be supported
> through the new subsystem, in a proper maintainable way.

We plan to eventually move ROCm over the drm interfaces once we get
user mode queues working on non-compute queues which is already in
progress. ROCm already uses the existing drm nodes and libdrm for a
number of things today (buffer sharing, media and compute command
submission in certain cases, etc.). I don't see much value in the
accel nodes for AMD products at this time. Even when we transition,
there are still a bunch of things that we'd need to think about, so
the current kfd node may stick around until we figure out a plan for
those areas. E.g., the kfd node provides platform level compute
topology information; e.g., the NUMA details for connected GPUs and
CPUs, non-GPU compute node information, cache level topologies, etc.

Alex

>
> Jason

\
 
 \ /
  Last update: 2022-10-25 16:22    [W:0.056 / U:0.108 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site