drm/amdgpu/userq: fix double jiffies conversion in hang detect timeout

Function amdgpu_userq_start_hang_detect_work() calls msecs_to_jiffies()
on adev->gfx_timeout/compute_timeout/sdma_timeout before arming
hang_detect_work. These timeout values already hold jiffies values from
amdgpu_device_get_job_timeout_settings() at device init.

This silently shrinks the real hang-detect deadline to (2 * HZ) ms
instead of the intended timeout. e.g. 500ms instead of the 2000ms
default on a CONFIG_HZ=250 kernel, only coincidentally correct at
HZ=1000. The shortened window is easily exceeded by ordinary
fence-completion latency, causing hang_detect_work to fire and
trigger a per-queue or full GPU reset for queues that are not
actually hung.

Pass the jiffies value directly to queue_delayed_work() instead of
converting it a second time.

Fixes: fc3336be9c62 ("drm/amd/amdgpu: Add independent hang detect work for user queue fence")
Signed-off-by: Sunil Khatri <sunil.khatri@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 6 insertions, 6 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c
index 5d07320a29b2..75d5ceaa53c6 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c
@@ -184,27 +184,27 @@ static void amdgpu_userq_hang_detect_work(struct work_struct *work)
 void amdgpu_userq_start_hang_detect_work(struct amdgpu_usermode_queue *queue)
 {
 	struct amdgpu_device *adev;
-	unsigned long timeout_ms;
+	unsigned long timeout_jiffies;
 
 	adev = queue->userq_mgr->adev;
 	/* Determine timeout based on queue type */
 	switch (queue->queue_type) {
 	case AMDGPU_RING_TYPE_GFX:
-		timeout_ms = adev->gfx_timeout;
+		timeout_jiffies = adev->gfx_timeout;
 		break;
 	case AMDGPU_RING_TYPE_COMPUTE:
-		timeout_ms = adev->compute_timeout;
+		timeout_jiffies = adev->compute_timeout;
 		break;
 	case AMDGPU_RING_TYPE_SDMA:
-		timeout_ms = adev->sdma_timeout;
+		timeout_jiffies = adev->sdma_timeout;
 		break;
 	default:
-		timeout_ms = adev->gfx_timeout;
+		timeout_jiffies = adev->gfx_timeout;
 		break;
 	}
 
 	queue_delayed_work(adev->reset_domain->wq, &queue->hang_detect_work,
-			   msecs_to_jiffies(timeout_ms));
+			   timeout_jiffies);
 }
 
 void amdgpu_userq_process_fence_irq(struct amdgpu_device *adev, u32 doorbell)