drm/amdgpu: cleanup and simplify amdgpu_vmid_grab_reserved

Drop the "_locked" from the name, cleanup and simplify the logic a bit.
Add missing comments.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Chunming Zhou <david1.zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
index 5761a65..51633fc 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
@@ -248,12 +248,22 @@ static int amdgpu_vmid_grab_idle(struct amdgpu_vm *vm,
        return 0;
 }
 
-/* idr_mgr->lock must be held */
-static int amdgpu_vmid_grab_reserved_locked(struct amdgpu_vm *vm,
-                                           struct amdgpu_ring *ring,
-                                           struct amdgpu_sync *sync,
-                                           struct dma_fence *fence,
-                                           struct amdgpu_job *job)
+/**
+ * amdgpu_vm_grab_reserved - try to assign reserved VMID
+ *
+ * @vm: vm to allocate id for
+ * @ring: ring we want to submit job to
+ * @sync: sync object where we add dependencies
+ * @fence: fence protecting ID from reuse
+ * @job: job who wants to use the VMID
+ *
+ * Try to assign a reserved VMID.
+ */
+static int amdgpu_vmid_grab_reserved(struct amdgpu_vm *vm,
+                                    struct amdgpu_ring *ring,
+                                    struct amdgpu_sync *sync,
+                                    struct dma_fence *fence,
+                                    struct amdgpu_job *job)
 {
        struct amdgpu_device *adev = ring->adev;
        unsigned vmhub = ring->funcs->vmhub;
@@ -261,18 +271,21 @@ static int amdgpu_vmid_grab_reserved_locked(struct amdgpu_vm *vm,
        struct amdgpu_vmid *id = vm->reserved_vmid[vmhub];
        struct amdgpu_vmid_mgr *id_mgr = &adev->vm_manager.id_mgr[vmhub];
        struct dma_fence *updates = sync->last_vm_update;
-       int r = 0;
-       struct dma_fence *flushed, *tmp;
        bool needs_flush = vm->use_cpu_for_update;
+       int r = 0;
+
+       if (updates && id->flushed_updates &&
+           updates->context == id->flushed_updates->context &&
+           !dma_fence_is_later(updates, id->flushed_updates))
+           updates = NULL;
+
+       if (id->owner != vm->entity.fence_context ||
+           job->vm_pd_addr != id->pd_gpu_addr ||
+           updates || !id->last_flush ||
+           (id->last_flush->context != fence_context &&
+            !dma_fence_is_signaled(id->last_flush))) {
+               struct dma_fence *tmp;
 
-       flushed  = id->flushed_updates;
-       if ((id->owner != vm->entity.fence_context) ||
-           (job->vm_pd_addr != id->pd_gpu_addr) ||
-           (updates && (!flushed || updates->context != flushed->context ||
-                       dma_fence_is_later(updates, flushed))) ||
-           (!id->last_flush || (id->last_flush->context != fence_context &&
-                                !dma_fence_is_signaled(id->last_flush)))) {
-               needs_flush = true;
                /* to prevent one context starved by another context */
                id->pd_gpu_addr = 0;
                tmp = amdgpu_sync_peek_fence(&id->active, ring);
@@ -280,6 +293,7 @@ static int amdgpu_vmid_grab_reserved_locked(struct amdgpu_vm *vm,
                        r = amdgpu_sync_fence(adev, sync, tmp, false);
                        return r;
                }
+               needs_flush = true;
        }
 
        /* Good we can use this VMID. Remember this submission as
@@ -287,10 +301,9 @@ static int amdgpu_vmid_grab_reserved_locked(struct amdgpu_vm *vm,
        */
        r = amdgpu_sync_fence(ring->adev, &id->active, fence, false);
        if (r)
-               goto out;
+               return r;
 
-       if (updates && (!flushed || updates->context != flushed->context ||
-                       dma_fence_is_later(updates, flushed))) {
+       if (updates) {
                dma_fence_put(id->flushed_updates);
                id->flushed_updates = dma_fence_get(updates);
        }
@@ -304,8 +317,7 @@ static int amdgpu_vmid_grab_reserved_locked(struct amdgpu_vm *vm,
        job->vmid = id - id_mgr->ids;
        job->pasid = vm->pasid;
        trace_amdgpu_vm_grab_id(vm, ring, job);
-out:
-       return r;
+       return 0;
 }
 
 /**
@@ -315,6 +327,7 @@ out:
  * @ring: ring we want to submit job to
  * @sync: sync object where we add dependencies
  * @fence: fence protecting ID from reuse
+ * @job: job who wants to use the VMID
  *
  * Allocate an id for the vm, adding fences to the sync obj as necessary.
  */
@@ -336,8 +349,7 @@ int amdgpu_vmid_grab(struct amdgpu_vm *vm, struct amdgpu_ring *ring,
                goto error;
 
        if (vm->reserved_vmid[vmhub]) {
-               r = amdgpu_vmid_grab_reserved_locked(vm, ring, sync,
-                                                    fence, job);
+               r = amdgpu_vmid_grab_reserved(vm, ring, sync, fence, job);
                mutex_unlock(&id_mgr->lock);
                return r;
        }