This update adds explanations to key functions that manage how the Kernel Fusion Driver (KFD) and Kernel Graphics Driver (KGD) share the GPU. amdgpu_gfx_enforce_isolation_wait_for_kfd: Controls the waiting period for KFD to ensure it takes turns with KGD in using the GPU. It uses a mutex to safely manage shared data, like timing and state, and tracks when KFD starts and stops waiting. amdgpu_gfx_enforce_isolation_ring_begin_use: Ensures KFD has enough time to run before new tasks are submitted to the GPU ring. It uses a mutex to synchronize access and may adjust the KFD scheduler. amdgpu_gfx_enforce_isolation_ring_end_use: Handles cleanup and state updates when finishing the use of a GPU ring. It may also adjust the KFD scheduler, using a mutex to manage shared data access. Cc: Christian König <christian.koenig@xxxxxxx> Cc: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx> Suggested-by: Alex Deucher <alexander.deucher@xxxxxxx> --- v2: - Incorporated feedbacks for function descriptions (Alex) drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c | 29 +++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c index e54f42e3797e..b1b133affbf9 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c @@ -1940,6 +1940,17 @@ void amdgpu_gfx_enforce_isolation_handler(struct work_struct *work) mutex_unlock(&adev->enforce_isolation_mutex); } +/** + * amdgpu_gfx_enforce_isolation_wait_for_kfd - Manage KFD wait period for process isolation + * @adev: amdgpu_device pointer + * @idx: Index of the GPU partition + * + * When kernel submissions come in, the jobs are given a time slice and once + * that time slice is up, if there are KFD user queues active, kernel + * submissions are blocked until KFD has had its time slice. Once the KFD time + * slice is up, KFD user queues are preempted and kernel submissions are + * unblocked and allowed to run again. + */ static void amdgpu_gfx_enforce_isolation_wait_for_kfd(struct amdgpu_device *adev, u32 idx) @@ -1985,6 +1996,15 @@ amdgpu_gfx_enforce_isolation_wait_for_kfd(struct amdgpu_device *adev, msleep(GFX_SLICE_PERIOD_MS); } +/** + * amdgpu_gfx_enforce_isolation_ring_begin_use - Begin use of a ring with enforced isolation + * @ring: Pointer to the amdgpu_ring structure + * + * Ring begin_use helper implementation for gfx which serializes access to the + * gfx IP between kernel submission IOCTLs and KFD user queues when isolation + * enforcement is enabled. The kernel submission IOCTLs and KFD user queues + * each get a time slice when both are active. + */ void amdgpu_gfx_enforce_isolation_ring_begin_use(struct amdgpu_ring *ring) { struct amdgpu_device *adev = ring->adev; @@ -2012,6 +2032,15 @@ void amdgpu_gfx_enforce_isolation_ring_begin_use(struct amdgpu_ring *ring) mutex_unlock(&adev->enforce_isolation_mutex); } +/** + * amdgpu_gfx_enforce_isolation_ring_end_use - End use of a ring with enforced isolation + * @ring: Pointer to the amdgpu_ring structure + * + * Ring end_use helper implementation for gfx which serializes access to the + * gfx IP between kernel submission IOCTLs and KFD user queues when isolation + * enforcement is enabled. The kernel submission IOCTLs and KFD user queues + * each get a time slice when both are active. + */ void amdgpu_gfx_enforce_isolation_ring_end_use(struct amdgpu_ring *ring) { struct amdgpu_device *adev = ring->adev; -- 2.34.1