drm/amdgpu: remove VM fault_credit handling

printk_ratelimit() is much better suited to limit the number of reported
VM faults.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c

@@ -3052,7 +3052,6 @@ int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm,
 	}
 
 	INIT_KFIFO(vm->faults);
-	vm->fault_credit = 16;
 
 	return 0;
 
@@ -3264,42 +3263,6 @@ void amdgpu_vm_fini(struct amdgpu_device *adev, struct amdgpu_vm *vm)
 		amdgpu_vmid_free_reserved(adev, vm, i);
 }
 
-/**
- * amdgpu_vm_pasid_fault_credit - Check fault credit for given PASID
- *
- * @adev: amdgpu_device pointer
- * @pasid: PASID do identify the VM
- *
- * This function is expected to be called in interrupt context.
- *
- * Returns:
- * True if there was fault credit, false otherwise
- */
-bool amdgpu_vm_pasid_fault_credit(struct amdgpu_device *adev,
-				  unsigned int pasid)
-{
-	struct amdgpu_vm *vm;
-
-	spin_lock(&adev->vm_manager.pasid_lock);
-	vm = idr_find(&adev->vm_manager.pasid_idr, pasid);
-	if (!vm) {
-		/* VM not found, can't track fault credit */
-		spin_unlock(&adev->vm_manager.pasid_lock);
-		return true;
-	}
-
-	/* No lock needed. only accessed by IRQ handler */
-	if (!vm->fault_credit) {
-		/* Too many faults in this VM */
-		spin_unlock(&adev->vm_manager.pasid_lock);
-		return false;
-	}
-
-	vm->fault_credit--;
-	spin_unlock(&adev->vm_manager.pasid_lock);
-	return true;
-}
-
 /**
  * amdgpu_vm_manager_init - init the VM manager
  *

drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h

@@ -229,9 +229,6 @@ struct amdgpu_vm {
 	/* Up to 128 pending retry page faults */
 	DECLARE_KFIFO(faults, u64, 128);
 
-	/* Limit non-retry fault storms */
-	unsigned int		fault_credit;
-
 	/* Points to the KFD process VM info */
 	struct amdkfd_process_info *process_info;
 
@@ -299,8 +296,6 @@ int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm,
 int amdgpu_vm_make_compute(struct amdgpu_device *adev, struct amdgpu_vm *vm, unsigned int pasid);
 void amdgpu_vm_release_compute(struct amdgpu_device *adev, struct amdgpu_vm *vm);
 void amdgpu_vm_fini(struct amdgpu_device *adev, struct amdgpu_vm *vm);
-bool amdgpu_vm_pasid_fault_credit(struct amdgpu_device *adev,
-				  unsigned int pasid);
 void amdgpu_vm_get_pd_bo(struct amdgpu_vm *vm,
 			 struct list_head *validated,
 			 struct amdgpu_bo_list_entry *entry);

drivers/gpu/drm/amd/amdgpu/cik_ih.c

@@ -237,23 +237,7 @@ static u32 cik_ih_get_wptr(struct amdgpu_device *adev)
  */
 static bool cik_ih_prescreen_iv(struct amdgpu_device *adev)
 {
-	u32 ring_index = adev->irq.ih.rptr >> 2;
-	u16 pasid;
-
-	switch (le32_to_cpu(adev->irq.ih.ring[ring_index]) & 0xff) {
-	case 146:
-	case 147:
-		pasid = le32_to_cpu(adev->irq.ih.ring[ring_index + 2]) >> 16;
-		if (!pasid || amdgpu_vm_pasid_fault_credit(adev, pasid))
-			return true;
-		break;
-	default:
-		/* Not a VM fault */
-		return true;
-	}
-
-	adev->irq.ih.rptr += 16;
-	return false;
+	return true;
 }
 
  /**

drivers/gpu/drm/amd/amdgpu/cz_ih.c

@@ -216,23 +216,7 @@ static u32 cz_ih_get_wptr(struct amdgpu_device *adev)
  */
 static bool cz_ih_prescreen_iv(struct amdgpu_device *adev)
 {
-	u32 ring_index = adev->irq.ih.rptr >> 2;
-	u16 pasid;
-
-	switch (le32_to_cpu(adev->irq.ih.ring[ring_index]) & 0xff) {
-	case 146:
-	case 147:
-		pasid = le32_to_cpu(adev->irq.ih.ring[ring_index + 2]) >> 16;
-		if (!pasid || amdgpu_vm_pasid_fault_credit(adev, pasid))
-			return true;
-		break;
-	default:
-		/* Not a VM fault */
-		return true;
-	}
-
-	adev->irq.ih.rptr += 16;
-	return false;
+	return true;
 }
 
 /**

drivers/gpu/drm/amd/amdgpu/iceland_ih.c

@@ -216,23 +216,7 @@ static u32 iceland_ih_get_wptr(struct amdgpu_device *adev)
  */
 static bool iceland_ih_prescreen_iv(struct amdgpu_device *adev)
 {
-	u32 ring_index = adev->irq.ih.rptr >> 2;
-	u16 pasid;
-
-	switch (le32_to_cpu(adev->irq.ih.ring[ring_index]) & 0xff) {
-	case 146:
-	case 147:
-		pasid = le32_to_cpu(adev->irq.ih.ring[ring_index + 2]) >> 16;
-		if (!pasid || amdgpu_vm_pasid_fault_credit(adev, pasid))
-			return true;
-		break;
-	default:
-		/* Not a VM fault */
-		return true;
-	}
-
-	adev->irq.ih.rptr += 16;
-	return false;
+	return true;
 }
 
 /**

drivers/gpu/drm/amd/amdgpu/tonga_ih.c

@@ -227,23 +227,7 @@ static u32 tonga_ih_get_wptr(struct amdgpu_device *adev)
  */
 static bool tonga_ih_prescreen_iv(struct amdgpu_device *adev)
 {
-	u32 ring_index = adev->irq.ih.rptr >> 2;
-	u16 pasid;
-
-	switch (le32_to_cpu(adev->irq.ih.ring[ring_index]) & 0xff) {
-	case 146:
-	case 147:
-		pasid = le32_to_cpu(adev->irq.ih.ring[ring_index + 2]) >> 16;
-		if (!pasid || amdgpu_vm_pasid_fault_credit(adev, pasid))
-			return true;
-		break;
-	default:
-		/* Not a VM fault */
-		return true;
-	}
-
-	adev->irq.ih.rptr += 16;
-	return false;
+	return true;
 }
 
 /**

drivers/gpu/drm/amd/amdgpu/vega10_ih.c

@@ -258,12 +258,9 @@ static bool vega10_ih_prescreen_iv(struct amdgpu_device *adev)
 	if (!pasid)
 		return true;
 
-	/* Not a retry fault, check fault credit */
-	if (!(dw5 & 0x80)) {
-		if (!amdgpu_vm_pasid_fault_credit(adev, pasid))
-			goto ignore_iv;
+	/* Not a retry fault */
+	if (!(dw5 & 0x80))
 		return true;
-	}
 
 	/* Track retry faults in per-VM fault FIFO. */
 	spin_lock(&adev->vm_manager.pasid_lock);