To better clarify what is happening in this function.

Signed-off-by: Alex Deucher <[email protected]>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index c8ce42200059..3c0bd6472a46 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -1419,6 +1419,9 @@ static int amdgpu_vm_update_ptes(struct 
amdgpu_vm_update_params *params,
                uint64_t incr, entry_end, pe_start;
                struct amdgpu_bo *pt;
 
+               /* make sure that the page tables covering the address range are
+                * actually allocated
+                */
                r = amdgpu_vm_alloc_pts(params->adev, params->vm, &cursor,
                                        params->direct);
                if (r)
@@ -1492,7 +1495,12 @@ static int amdgpu_vm_update_ptes(struct 
amdgpu_vm_update_params *params,
                } while (frag_start < entry_end);
 
                if (amdgpu_vm_pt_descendant(adev, &cursor)) {
-                       /* Free all child entries */
+                       /* Free all child entries.
+                        * Update the tables with the flags and addresses and 
free up subsequent
+                        * tables in the case of huge pages or freed up areas.
+                        * This is the maximum you can free, because all other 
page tables are not
+                        * completely covered by the range and so potentially 
still in use.
+                        */
                        while (cursor.pfn < frag_start) {
                                amdgpu_vm_free_pts(adev, params->vm, &cursor);
                                amdgpu_vm_pt_next(adev, &cursor);
-- 
2.23.0

_______________________________________________
amd-gfx mailing list
[email protected]
https://lists.freedesktop.org/mailman/listinfo/amd-gfx

Reply via email to