[PATCH 3/3] drm/amdkfd: don't sleep when event age unmatch

[James Zhu]

Don't sleep when event age unmatch, and update last_event_age.
It is only for KFD_EVENT_TYPE_SIGNAL which is checked by user space.

Signed-off-by: James Zhu <James.Zhu at amd.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_events.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_events.c b/drivers/gpu/drm/amd/amdkfd/kfd_events.c
index b27a79c5f826..23e154811471 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_events.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_events.c
@@ -964,6 +964,19 @@ int kfd_wait_on_events(struct kfd_process *p,
 					event_data.event_id);
 		if (ret)
 			goto out_unlock;
+
+		/* last_event_age = 0 reserved for backward compatible */
+		if (event_data.last_event_age &&
+			event_waiters[i].event->event_age != event_data.last_event_age) {
+			event_data.last_event_age = event_waiters[i].event->event_age;
+			WRITE_ONCE(event_waiters[i].activated, true);
+
+			if (copy_to_user(&events[i], &event_data,
+				sizeof(struct kfd_event_data))) {
+				ret = -EFAULT;
+				goto out_unlock;
+			}
+		}
 	}
 
 	/* Check condition once. */
-- 
2.34.1