If the os fence is the only kind that's supported, fail a submit if the
user wants fences but doesn't explicitly request sync fences, expecting
syncpoints. Syncpoint support is advertised to userspace in the gpu
characteristics, so userspace already has the knowledge to request the
correct sync type.
Do this check at the ioctl level. The in-kernel stuff that needs submits
(cde, copyengine) can work without syncpoints and sync fences are used
only in userspace.
Fail a submit also if CONFIG_SYNC is not set and sync fences are
requested. Lack of kernel support doesn't guarantee that userspace would
still wrongly want that.
Clarify the deferred cleanup requirements. The sync framework is needed
only for post sync fences, but deferred cleanup is still always needed
with semaphores because the internal tracking is done with dynamically
allocated (although small) objects.
Jira NVGPU-4548
Change-Id: I2e5a6554930cb413b2bb46ddfe388e41390bc7e4
Signed-off-by: Konsta Hölttä <kholtta@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvgpu/+/2321715
(cherry picked from commit d870956170906eae1088846ec05266c859669771)
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvgpu/+/2318157
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
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