drm/amdgpu: fix concurrent VM flushes on Vega/Navi v2

commit 20a5f5a98e1bb3d40acd97e89299e8c2d22784be upstream.

Starting with Vega the hardware supports concurrent flushes
of VMID which can be used to implement per process VMID
allocation.

But concurrent flushes are mutual exclusive with back to
back VMID allocations, fix this to avoid a VMID used in
two ways at the same time.

v2: don't set ring to NULL

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: James Zhu <James.Zhu@amd.com>
Tested-by: James Zhu <James.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

3 files changed, 18 insertions, 8 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
index 6e9a9e5dbea0..90e16d14e6c3 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
@@ -215,7 +215,11 @@ static int amdgpu_vmid_grab_idle(struct amdgpu_vm *vm,
 	/* Check if we have an idle VMID */
 	i = 0;
 	list_for_each_entry((*idle), &id_mgr->ids_lru, list) {
-		fences[i] = amdgpu_sync_peek_fence(&(*idle)->active, ring);
+		/* Don't use per engine and per process VMID at the same time */
+		struct amdgpu_ring *r = adev->vm_manager.concurrent_flush ?
+			NULL : ring;
+
+		fences[i] = amdgpu_sync_peek_fence(&(*idle)->active, r);
 		if (!fences[i])
 			break;
 		++i;
@@ -280,7 +284,7 @@ static int amdgpu_vmid_grab_reserved(struct amdgpu_vm *vm,
 	if (updates && (*id)->flushed_updates &&
 	    updates->context == (*id)->flushed_updates->context &&
 	    !dma_fence_is_later(updates, (*id)->flushed_updates))
-	    updates = NULL;
+		updates = NULL;
 
 	if ((*id)->owner != vm->immediate.fence_context ||
 	    job->vm_pd_addr != (*id)->pd_gpu_addr ||
@@ -289,6 +293,10 @@ static int amdgpu_vmid_grab_reserved(struct amdgpu_vm *vm,
 	     !dma_fence_is_signaled((*id)->last_flush))) {
 		struct dma_fence *tmp;
 
+		/* Don't use per engine and per process VMID at the same time */
+		if (adev->vm_manager.concurrent_flush)
+			ring = NULL;
+
 		/* to prevent one context starved by another context */
 		(*id)->pd_gpu_addr = 0;
 		tmp = amdgpu_sync_peek_fence(&(*id)->active, ring);
@@ -364,12 +372,7 @@ static int amdgpu_vmid_grab_used(struct amdgpu_vm *vm,
 		if (updates && (!flushed || dma_fence_is_later(updates, flushed)))
 			needs_flush = true;
 
-		/* Concurrent flushes are only possible starting with Vega10 and
-		 * are broken on Navi10 and Navi14.
-		 */
-		if (needs_flush && (adev->asic_type < CHIP_VEGA10 ||
-				    adev->asic_type == CHIP_NAVI10 ||
-				    adev->asic_type == CHIP_NAVI14))
+		if (needs_flush && !adev->vm_manager.concurrent_flush)
 			continue;
 
 		/* Good, we can use this VMID. Remember this submission as
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 605d1545274c..b47829ff30af 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -3173,6 +3173,12 @@ void amdgpu_vm_manager_init(struct amdgpu_device *adev)
 {
 	unsigned i;
 
+	/* Concurrent flushes are only possible starting with Vega10 and
+	 * are broken on Navi10 and Navi14.
+	 */
+	adev->vm_manager.concurrent_flush = !(adev->asic_type < CHIP_VEGA10 ||
+					      adev->asic_type == CHIP_NAVI10 ||
+					      adev->asic_type == CHIP_NAVI14);
 	amdgpu_vmid_mgr_init(adev);
 
 	adev->vm_manager.fence_context =
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
index 58c83a7ad0fd..c4218800e043 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
@@ -325,6 +325,7 @@ struct amdgpu_vm_manager {
 	/* Handling of VMIDs */
 	struct amdgpu_vmid_mgr			id_mgr[AMDGPU_MAX_VMHUBS];
 	unsigned int				first_kfd_vmid;
+	bool					concurrent_flush;
 
 	/* Handling of VM fences */
 	u64					fence_context;