[PATCH 3/3] drm/amdkfd: add invalid pages debug at vram migration

[Alex Sierra]

This is for debug purposes only.
It conditionally generates partial migrations to test mixed
CPU/GPU memory domain pages in a prange easily.

Signed-off-by: Alex Sierra <alex.sierra at amd.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_migrate.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
index e1cc844b2f4e..4c6e340393fb 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
@@ -403,6 +403,20 @@ svm_migrate_copy_to_vram(struct amdgpu_device *adev, struct svm_range *prange,
 		}
 	}
 
+#ifdef DEBUG_FORCE_MIXED_DOMAINS
+	for (i = 0, j = 0; i < npages; i += 4, j++) {
+		if (j & 1)
+			continue;
+		svm_migrate_put_vram_page(adev, dst[i]);
+		migrate->dst[i] = 0;
+		svm_migrate_put_vram_page(adev, dst[i + 1]);
+		migrate->dst[i + 1] = 0;
+		svm_migrate_put_vram_page(adev, dst[i + 2]);
+		migrate->dst[i + 2] = 0;
+		svm_migrate_put_vram_page(adev, dst[i + 3]);
+		migrate->dst[i + 3] = 0;
+	}
+#endif
 out:
 	return r;
 }
-- 
2.17.1