Tejal Kudav ab2b0b5949 gpu: nvgpu: Set unserviceable flag early during RC ...

During recovery, we set ch->unserviceable at the end after we preempt
the TSG and reset the engines. It might be too late and user-space
might submit more work to the broken channel which is not desirable.
Move setting this unserviceable flag right at the start
of recovery sequence.
Another thread doing a submit can still read the unserviceable flag
just before it is set here, leaving that submit stuck if recovery
completes before the submit thread advances enough to set up a post
fence visible for other threads. This could be fixed with a big lock
or with a double check at the end of the submit code after the job
data has been made visible.
We still release the fences, semaphore and error notifier wait queues
at the end; so user-space would not trigger channel unbind while
channel is being recovered.

Also, change the handle_mmu_fault APIs to return void as the
debug_dump return value is not used in any of the caller APIs.

JIRA NVGPU-5843

Change-Id: Ib42c2816dd1dca542e4f630805411cab75fad90e
Signed-off-by: Tejal Kudav <tkudav@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvgpu/+/2385256
Reviewed-by: automaticguardword <automaticguardword@nvidia.com>
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
Reviewed-by: svc-mobile-misra <svc-mobile-misra@nvidia.com>
Reviewed-by: svc-mobile-cert <svc-mobile-cert@nvidia.com>
Reviewed-by: Konsta Holtta <kholtta@nvidia.com>
Reviewed-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
GVS: Gerrit_Virtual_Submit
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

2020-12-15 14:13:28 -06:00

60 KiB

Raw Blame History

View Raw