[PATCH] drm/amdkfd: fix cp hang in eviction

[Huang, JinHuiEric]

The cp hang occurs in OCL conformance test only on supermicro
platform which has 40 cores and the test generates 40 threads.
The root cause is race condition in non-protected flags.

The fix is to add flags of is_evicted and is_active(init_mqd())
into protected area.

Signed-off-by: Eric Huang <JinhuiEric.Huang at amd.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
index 9ffdda5..f23e17b 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
@@ -1157,12 +1157,7 @@ static int create_queue_cpsch(struct device_queue_manager *dqm, struct queue *q,
 
 	mqd_mgr = dqm->mqd_mgrs[get_mqd_type_from_queue_type(
 			q->properties.type)];
-	/*
-	 * Eviction state logic: mark all queues as evicted, even ones
-	 * not currently active. Restoring inactive queues later only
-	 * updates the is_evicted flag but is a no-op otherwise.
-	 */
-	q->properties.is_evicted = !!qpd->evicted;
+
 	if (q->properties.type == KFD_QUEUE_TYPE_SDMA ||
 		q->properties.type == KFD_QUEUE_TYPE_SDMA_XGMI)
 		dqm->asic_ops.init_sdma_vm(dqm, q, qpd);
@@ -1173,9 +1168,16 @@ static int create_queue_cpsch(struct device_queue_manager *dqm, struct queue *q,
 		retval = -ENOMEM;
 		goto out_deallocate_doorbell;
 	}
+
+	dqm_lock(dqm);
+	/*
+	 * Eviction state logic: mark all queues as evicted, even ones
+	 * not currently active. Restoring inactive queues later only
+	 * updates the is_evicted flag but is a no-op otherwise.
+	 */
+	q->properties.is_evicted = !!qpd->evicted;
 	mqd_mgr->init_mqd(mqd_mgr, &q->mqd, q->mqd_mem_obj,
 				&q->gart_mqd_addr, &q->properties);
-	dqm_lock(dqm);
 
 	list_add(&q->list, &qpd->queues_list);
 	qpd->queue_count++;
-- 
2.7.4