Re: [PATCH 6/8] drm/i915: reprogram NOA muxes on context switch when using perf

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 25/04/18 12:57, Chris Wilson wrote:
Quoting Lionel Landwerlin (2018-04-25 12:45:19)
If some of the contexts submitting workloads to the GPU have been
configured to shutdown slices/subslices, we might loose the NOA
configurations written in the NOA muxes. We need to reprogram them at
context switch.
On every single batchbuffer, no way. That's around a 33% latency hit,
ignoring the cost of what's inside the wa_bb.

If they are not context saved, userspace isn't going to be allowed to
modify them. So why do we need this? If they not context saved, then the
kernel needs to control them and doesn't need to reset around every
batch, just the one's that want non-default (fancier if we handle
preemption)?
-Chris

These are neither context saved, nor power saved :(

I can't tell whether the GuC might schedule things behind our back.
But eventually that will happen anyway. So that's why I put the reprogramming in per ctx wa.
Agreed, it sucks.

I'll look into the fancier things.

Thanks,

-
Lionel
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx




[Index of Archives]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]
  Powered by Linux