Files
linux-nvgpu/arch
Sagar Kamble f55fd5dc8c gpu: nvgpu: multiple address spaces support for subcontexts
This patch introduces following relationships among various nvgpu
objects to support multiple address spaces with subcontexts.
IOCTLs setting the relationships are shown in the braces.

nvgpu_tsg             1<---->n nvgpu_tsg_subctx (TSG_BIND_CHANNEL_EX)
nvgpu_tsg             1<---->n nvgpu_gr_ctx_mappings (ALLOC_OBJ_CTX)

nvgpu_tsg_subctx      1<---->1 nvgpu_gr_subctx (ALLOC_OBJ_CTX)
nvgpu_tsg_subctx      1<---->n nvgpu_channel (TSG_BIND_CHANNEL_EX)

nvgpu_gr_ctx_mappings 1<---->n nvgpu_gr_subctx (ALLOC_OBJ_CTX)
nvgpu_gr_ctx_mappings 1<---->1 vm_gk20a (ALLOC_OBJ_CTX)

On unbinding the channel, objects are deleted according
to dependencies.

Without subcontexts, gr_ctx buffers mappings are maintained in the
struct nvgpu_gr_ctx. For subcontexts, they are maintained in the
struct nvgpu_gr_subctx.

Preemption buffer with index NVGPU_GR_CTX_PREEMPT_CTXSW and PM
buffer with index NVGPU_GR_CTX_PM_CTX are to be mapped in all
subcontexts when they are programmed from respective ioctls.

Global GR context buffers are to be programmed only for VEID0.
Based on the channel object class the state is patched in
the patch buffer in every ALLOC_OBJ_CTX call unlike
setting it for only first channel like before.

PM and preemptions buffers programming is protected under TSG
ctx_init_lock.

tsg->vm is now removed. VM reference for gr_ctx buffers mappings
is managed through gr_ctx or gr_subctx mappings object.

For vGPU, gr_subctx and mappings objects are created to reference
VMs for the gr_ctx lifetime.

The functions nvgpu_tsg_subctx_alloc_gr_subctx and nvgpu_tsg_-
subctx_setup_subctx_header sets up the subcontext struct header
for native driver.

The function nvgpu_tsg_subctx_alloc_gr_subctx is called from
vgpu to manage the gr ctx mapping references.

free_subctx is now done when unbinding channel considering
references to the subcontext by other channels. It will unmap
the buffers in native driver case. It will just release the
VM reference in vgpu case.

Note that TEGRA_VGPU_CMD_FREE_CTX_HEADER ioctl is not called
by vgpu any longer as it would be taken care by native driver.

Bug 3677982

Change-Id: Ia439b251ff452a49f8514498832e24d04db86d2f
Signed-off-by: Sagar Kamble <skamble@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvgpu/+/2718760
Reviewed-by: Scott Long <scottl@nvidia.com>
Reviewed-by: Ankur Kishore <ankkishore@nvidia.com>
GVS: Gerrit_Virtual_Submit <buildbot_gerritrpt@nvidia.com>
2022-09-08 20:59:59 -07:00
..
2022-02-01 09:50:45 -08:00