drm/amdgpu: change vm->task_info handling

This patch changes the handling and lifecycle of vm->task_info object.
The major changes are:
- vm->task_info is a dynamically allocated ptr now, and its uasge is
  reference counted.
- introducing two new helper funcs for task_info lifecycle management
    - amdgpu_vm_get_task_info: reference counts up task_info before
      returning this info
    - amdgpu_vm_put_task_info: reference counts down task_info
- last put to task_info() frees task_info from the vm.

This patch also does logistical changes required for existing usage
of vm->task_info.

V2: Do not block all the prints when task_info not found (Felix)

V3: Fixed review comments from Felix
   - Fix wrong indentation
   - No debug message for -ENOMEM
   - Add NULL check for task_info
   - Do not duplicate the debug messages (ti vs no ti)
   - Get first reference of task_info in vm_init(), put last
     in vm_fini()

V4: Fixed review comments from Felix
   - fix double reference increment in create_task_info
   - change amdgpu_vm_get_task_info_pasid
   - additional changes in amdgpu_gem.c while porting

Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Shashank Sharma <shashank.sharma@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 14 insertions, 7 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
index 9f6b5e1ccf34..7f95039bb37d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
@@ -203,10 +203,11 @@ struct amdgpu_vm_pte_funcs {
 };
 
 struct amdgpu_task_info {
-	char	process_name[TASK_COMM_LEN];
-	char	task_name[TASK_COMM_LEN];
-	pid_t	pid;
-	pid_t	tgid;
+	char		process_name[TASK_COMM_LEN];
+	char		task_name[TASK_COMM_LEN];
+	pid_t		pid;
+	pid_t		tgid;
+	struct kref	refcount;
 };
 
 /**
@@ -370,7 +371,7 @@ struct amdgpu_vm {
 	uint64_t		pd_phys_addr;
 
 	/* Some basic info about the task */
-	struct amdgpu_task_info task_info;
+	struct amdgpu_task_info *task_info;
 
 	/* Store positions of group of BOs */
 	struct ttm_lru_bulk_move lru_bulk_move;
@@ -511,8 +512,14 @@ bool amdgpu_vm_need_pipeline_sync(struct amdgpu_ring *ring,
 				  struct amdgpu_job *job);
 void amdgpu_vm_check_compute_bug(struct amdgpu_device *adev);
 
-void amdgpu_vm_get_task_info(struct amdgpu_device *adev, u32 pasid,
-			     struct amdgpu_task_info *task_info);
+struct amdgpu_task_info *
+amdgpu_vm_get_task_info_pasid(struct amdgpu_device *adev, u32 pasid);
+
+struct amdgpu_task_info *
+amdgpu_vm_get_task_info_vm(struct amdgpu_vm *vm);
+
+void amdgpu_vm_put_task_info(struct amdgpu_task_info *task_info);
+
 bool amdgpu_vm_handle_fault(struct amdgpu_device *adev, u32 pasid,
 			    u32 vmid, u32 node_id, uint64_t addr,
 			    bool write_fault);