amdkfd: Add packet manager module

[Dan Carpenter]

Hello Ben Goz,

The patch 241f24f82363: "amdkfd: Add packet manager module" from Jul
17, 2014, leads to the following static checker warning:

	drivers/gpu/drm/amd/amdkfd/kfd_packet_manager.c:357 pm_send_set_resources()
	error: potentially using uninitialized 'packet'.

drivers/gpu/drm/amd/amdkfd/kfd_packet_manager.c
   344  int pm_send_set_resources(struct packet_manager *pm,
   345                                  struct scheduling_resources *res)
   346  {
   347          struct pm4_set_resources *packet;
   348  
   349          BUG_ON(!pm || !res);
   350  
   351          pr_debug("kfd: In func %s\n", __func__);
   352  
   353          mutex_lock(&pm->lock);
   354          pm->priv_queue->acquire_packet_buffer(pm->priv_queue,
   355                                          sizeof(*packet) / sizeof(uint32_t),
   356                          (unsigned int **)&packet);

If we added error handling to ->acquire_packet_buffer() or if that
function set packet to NULL on error, either one of those would silence
this static checker warning (from pre-release Smatch checks).

   357          if (packet == NULL) {
   358                  mutex_unlock(&pm->lock);
   359                  pr_err("kfd: failed to allocate buffer on kernel queue\n");
   360                  return -ENOMEM;
   361          }
   362  

regards,
dan carpenter