[PATCH v4 4/5] drm/xe: Wire up dmem cgroup reclaim for VRAM manager

["Thomas Hellström" <thomas.hellstrom@linux.intel.com>]

Register the VRAM manager with the dmem cgroup reclaim infrastructure
so that lowering dmem.max below current VRAM usage triggers TTM
eviction rather than failing with -EBUSY.

v4:
- Rebased on drm-tip; dropped the XE_PL_STOLEN guard as stolen memory
  uses a separate TTM manager and never calls __xe_ttm_vram_mgr_init().

Assisted-by: GitHub_Copilot:claude-sonnet-4.6
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
---
 drivers/gpu/drm/xe/xe_ttm_vram_mgr.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_ttm_vram_mgr.c b/drivers/gpu/drm/xe/xe_ttm_vram_mgr.c
index b518f7dec680..d8d596d8575b 100644
--- a/drivers/gpu/drm/xe/xe_ttm_vram_mgr.c
+++ b/drivers/gpu/drm/xe/xe_ttm_vram_mgr.c
@@ -299,14 +299,10 @@ int __xe_ttm_vram_mgr_init(struct xe_device *xe, struct xe_ttm_vram_mgr *mgr,
 			   u64 default_page_size)
 {
 	struct ttm_resource_manager *man = &mgr->manager;
+	struct dmem_cgroup_region *cg;
 	const char *name;
 	int err;
 
-	name = mem_type == XE_PL_VRAM0 ? "vram0" : "vram1";
-	man->cg = drmm_cgroup_register_region(&xe->drm, name, size);
-	if (IS_ERR(man->cg))
-		return PTR_ERR(man->cg);
-
 	man->func = &xe_ttm_vram_mgr_func;
 	mgr->mem_type = mem_type;
 	err = drmm_mutex_init(&xe->drm, &mgr->lock);
@@ -317,6 +313,14 @@ int __xe_ttm_vram_mgr_init(struct xe_device *xe, struct xe_ttm_vram_mgr *mgr,
 	mgr->visible_avail = io_size;
 
 	ttm_resource_manager_init(man, &xe->ttm, size);
+
+	name = mem_type == XE_PL_VRAM0 ? "vram0" : "vram1";
+	cg = drmm_cgroup_register_region(&xe->drm, name, size);
+	if (IS_ERR(cg))
+		return PTR_ERR(cg);
+
+	ttm_resource_manager_set_dmem_region(man, cg);
+
 	err = gpu_buddy_init(&mgr->mm, man->size, default_page_size);
 	if (err)
 		return err;
-- 
2.54.0