[PATCH] drm/amdgpu: only update spm vmid at first time

[Yintian Tao]

Original idea is from Monk which only update spm vmid
at first time which can release the frequent r/w register
burden under virtualization.

v2: set spm_vmid_updated to false when job timedout

Signed-off-by: Yintian Tao <yttao at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_job.c | 3 +++
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c  | 8 ++++++--
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h  | 2 ++
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
index 35c381ec0423..3bf59dfef05d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
@@ -50,6 +50,9 @@ static void amdgpu_job_timedout(struct drm_sched_job *s_job)
 	DRM_ERROR("Process information: process %s pid %d thread %s pid %d\n",
 		  ti.process_name, ti.tgid, ti.task_name, ti.pid);
 
+	if (job->vm)
+		job->vm->spm_vmid_updated = false;
+
 	if (amdgpu_device_should_recover_gpu(ring->adev)) {
 		amdgpu_device_gpu_recover(ring->adev, job);
 	} else {
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index accbb34ea670..636a6d23fd96 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -1080,11 +1080,14 @@ int amdgpu_vm_flush(struct amdgpu_ring *ring, struct amdgpu_job *job,
 	struct dma_fence *fence = NULL;
 	bool pasid_mapping_needed = false;
 	unsigned patch_offset = 0;
-	bool update_spm_vmid_needed = (job->vm && (job->vm->reserved_vmid[vmhub] != NULL));
+	bool update_spm_vmid_needed = (job->vm && (job->vm->reserved_vmid[vmhub] != NULL) &&
+				       !job->vm->spm_vmid_updated);
 	int r;
 
-	if (update_spm_vmid_needed && adev->gfx.rlc.funcs->update_spm_vmid)
+	if (update_spm_vmid_needed && adev->gfx.rlc.funcs->update_spm_vmid) {
 		adev->gfx.rlc.funcs->update_spm_vmid(adev, job->vmid);
+		job->vm->spm_vmid_updated = true;
+	}
 
 	if (amdgpu_vmid_had_gpu_reset(adev, id)) {
 		gds_switch_needed = true;
@@ -2797,6 +2800,7 @@ int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm,
 	int r, i;
 
 	vm->va = RB_ROOT_CACHED;
+	vm->spm_vmid_updated = false;
 	for (i = 0; i < AMDGPU_MAX_VMHUBS; i++)
 		vm->reserved_vmid[i] = NULL;
 	INIT_LIST_HEAD(&vm->evicted);
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
index ea771d84bf2b..02409e0ecf2c 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
@@ -319,6 +319,8 @@ struct amdgpu_vm {
 	bool			bulk_moveable;
 	/* Flag to indicate if VM is used for compute */
 	bool			is_compute_context;
+	/* flag to represent whether spm vmid has been updated */
+	bool			spm_vmid_updated;
 };
 
 struct amdgpu_vm_manager {
-- 
2.17.1