[PATCH v4 29/33] drm/xe: Basic SVM BO eviction

[Matthew Brost <matthew.brost@xxxxxxxxx>]

Wire xe_bo_move to GPU SVM migration via new helper xe_svm_bo_evict.

v2:
 - Use xe_svm_bo_evict
 - Drop bo->range
v3:
 - Kernel doc (Thomas)
v4:
 - Add missing xe_bo.c code

Signed-off-by: Matthew Brost <matthew.brost@xxxxxxxxx>
---
 drivers/gpu/drm/xe/xe_bo.c  | 19 +++++++++++++++++++
 drivers/gpu/drm/xe/xe_svm.c | 15 ++++++++++++++-
 drivers/gpu/drm/xe/xe_svm.h |  3 +++
 3 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c
index 20c96709e267..657687ee70d0 100644
--- a/drivers/gpu/drm/xe/xe_bo.c
+++ b/drivers/gpu/drm/xe/xe_bo.c
@@ -255,6 +255,8 @@ int xe_bo_placement_for_flags(struct xe_device *xe, struct xe_bo *bo,
 static void xe_evict_flags(struct ttm_buffer_object *tbo,
 			   struct ttm_placement *placement)
 {
+	struct xe_bo *bo;
+
 	if (!xe_bo_is_xe_bo(tbo)) {
 		/* Don't handle scatter gather BOs */
 		if (tbo->type == ttm_bo_type_sg) {
@@ -266,6 +268,12 @@ static void xe_evict_flags(struct ttm_buffer_object *tbo,
 		return;
 	}
 
+	bo = ttm_to_xe_bo(tbo);
+	if (bo->flags & XE_BO_FLAG_CPU_ADDR_MIRROR) {
+		*placement = sys_placement;
+		return;
+	}
+
 	/*
 	 * For xe, sg bos that are evicted to system just triggers a
 	 * rebind of the sg list upon subsequent validation to XE_PL_TT.
@@ -710,6 +718,17 @@ static int xe_bo_move(struct ttm_buffer_object *ttm_bo, bool evict,
 		goto out;
 	}
 
+	if (!move_lacks_source && (bo->flags & XE_BO_FLAG_CPU_ADDR_MIRROR) &&
+	    new_mem->mem_type == XE_PL_SYSTEM) {
+		ret = xe_svm_bo_evict(bo);
+		if (!ret) {
+			drm_dbg(&xe->drm, "Evict system allocator BO success\n");
+			ttm_bo_move_null(ttm_bo, new_mem);
+		}
+
+		goto out;
+	}
+
 	if (old_mem_type == XE_PL_SYSTEM && new_mem->mem_type == XE_PL_TT && !handle_system_ccs) {
 		ttm_bo_move_null(ttm_bo, new_mem);
 		goto out;
diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c
index fc030855d078..dafc5061eb42 100644
--- a/drivers/gpu/drm/xe/xe_svm.c
+++ b/drivers/gpu/drm/xe/xe_svm.c
@@ -768,6 +768,20 @@ bool xe_svm_has_mapping(struct xe_vm *vm, u64 start, u64 end)
 	return drm_gpusvm_has_mapping(&vm->svm.gpusvm, start, end);
 }
 
+/**
+ * xe_svm_bo_evict() - SVM evict BO to system memory
+ * @bo: BO to evict
+ *
+ * SVM evict BO to system memory. GPU SVM layer ensures all device pages
+ * are evicted before returning.
+ *
+ * Return: 0 on success standard error code otherwise
+ */
+int xe_svm_bo_evict(struct xe_bo *bo)
+{
+	return drm_gpusvm_evict_to_ram(&bo->devmem_allocation);
+}
+
 #if IS_ENABLED(CONFIG_DRM_XE_DEVMEM_MIRROR)
 static struct drm_pagemap_dma_addr
 xe_drm_pagemap_map_dma(struct drm_pagemap *dpagemap,
@@ -795,7 +809,6 @@ static const struct drm_pagemap_ops xe_drm_pagemap_ops = {
 	.map_dma = xe_drm_pagemap_map_dma,
 };
 
->>>>>>> 133db8ade5f0 (drm/xe: Add drm_pagemap ops to SVM)
 /**
  * xe_devm_add: Remap and provide memmap backing for device memory
  * @tile: tile that the memory region belongs to
diff --git a/drivers/gpu/drm/xe/xe_svm.h b/drivers/gpu/drm/xe/xe_svm.h
index 4c2576162c39..77dec5aae0ee 100644
--- a/drivers/gpu/drm/xe/xe_svm.h
+++ b/drivers/gpu/drm/xe/xe_svm.h
@@ -11,6 +11,7 @@
 
 #define XE_INTERCONNECT_VRAM DRM_INTERCONNECT_DRIVER
 
+struct xe_bo;
 struct xe_mem_region;
 struct xe_tile;
 struct xe_vm;
@@ -56,6 +57,8 @@ int xe_svm_handle_pagefault(struct xe_vm *vm, struct xe_vma *vma,
 
 bool xe_svm_has_mapping(struct xe_vm *vm, u64 start, u64 end);
 
+int xe_svm_bo_evict(struct xe_bo *bo);
+
 static inline bool xe_svm_range_pages_valid(struct xe_svm_range *range)
 {
 	return drm_gpusvm_range_pages_valid(range->base.gpusvm, &range->base);
-- 
2.34.1