[PATCH AUTOSEL for 4.14 010/135] drm/amdgpu: bypass lru touch for KIQ ring submission

From: alexander . levin
Date: Thu Dec 07 2017 - 13:15:38 EST


From: Pixel Ding <Pixel.Ding@xxxxxxx>

[ Upstream commit dce1e131dd4dc68099ff1b70aa03cd2d0acf8639 ]

KIQ ring submission is used for register accessing on SRIOV
VF that could happen both in irq enabled and irq disabled cases.
Inversion lock could happen on adev->ring_lru_list_lock, while
this operation is useless and just adds overhead in this use
case.

Signed-off-by: Pixel Ding <Pixel.Ding@xxxxxxx>
Reviewed-by: Monk Liu <Monk.Liu@xxxxxxx>
Reviewed-by: Christian KÃnig <christian.koenig@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
index 5ce65280b396..90adff83e489 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
@@ -136,7 +136,8 @@ void amdgpu_ring_commit(struct amdgpu_ring *ring)
if (ring->funcs->end_use)
ring->funcs->end_use(ring);

- amdgpu_ring_lru_touch(ring->adev, ring);
+ if (ring->funcs->type != AMDGPU_RING_TYPE_KIQ)
+ amdgpu_ring_lru_touch(ring->adev, ring);
}

/**
--
2.11.0