From 7680fd689ecf7d11bf2dfdba41dc2f33cde2bbe7 Mon Sep 17 00:00:00 2001 From: Konsta Holtta Date: Tue, 16 May 2017 13:47:58 +0300 Subject: gpu: nvgpu: hold power ref for deterministic channels To support deterministic channels even with platforms where railgating is supported, have each deterministic-marked channel hold a power reference during their lifetime, and skip taking power refs for jobs in submit path for those. Previously, railgating blocked deterministic submits in general because of gk20a_busy()/gk20a_idle() calls in submit path possibly taking time and more significantly because the gpu may need turning on which takes a nondeterministic and long amount of time. As an exception, gk20a_do_idle() can still block deterministic submits until gk20a_do_unidle() is called. Add a rwsem to guard this. VPR resize needs do_idle, which conflicts with deterministic channels' requirement to keep the GPU on. This is documented in the ioctl header now. Make NVGPU_GPU_FLAGS_SUPPORT_DETERMINISTIC_SUBMIT_NO_JOBTRACKING always set in the gpu characteristics now that it's supported. The only thing left now blocking NVGPU_GPU_FLAGS_SUPPORT_DETERMINISTIC_SUBMIT_FULL is the sync framework. Make the channel debug dump show which channels are deterministic. Bug 200291300 Jira NVGPU-70 Change-Id: I47b6f3a8517cd6e4255f6ca2855e3dd912e4f5f3 Signed-off-by: Konsta Holtta Reviewed-on: http://git-master/r/1483038 Reviewed-by: mobile promotions Tested-by: mobile promotions --- include/uapi/linux/nvgpu.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/nvgpu.h b/include/uapi/linux/nvgpu.h index e7d37221..00081c64 100644 --- a/include/uapi/linux/nvgpu.h +++ b/include/uapi/linux/nvgpu.h @@ -1359,6 +1359,10 @@ struct nvgpu_alloc_gpfifo_ex_args { /* * Channel shall exhibit deterministic behavior in the submit path. * + * NOTE: as an exception, VPR resize may still cause the GPU to reset at any + * time, which is not deterministic behavior. If this is not acceptable, the + * user has to make sure that VPR resize does not occur. + * * With this flag, any submits with in-kernel job tracking also require that * num_inflight_jobs is nonzero, and additionally that * NVGPU_GPU_FLAGS_SUPPORT_DETERMINISTIC_SUBMIT_FULL is found in gpu -- cgit v1.2.2