drm/xe: Adjust page count tracepoints in shrinker

Page accounting can change via the shrinker without calling
xe_ttm_tt_unpopulate(), which normally updates page count tracepoints
through update_global_total_pages. Add a call to
update_global_total_pages when the shrinker successfully shrinks a BO.

v2:
 - Don't adjust global accounting when pinning (Stuart)

Cc: stable@vger.kernel.org
Fixes: ce3d39f ("drm/xe/bo: add GPU memory trace points")
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Stuart Summers <stuart.summers@intel.com>
Link: https://patch.msgid.link/20260107205732.2267541-1-matthew.brost@intel.com
(cherry picked from commit cc54eab)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>

Author: mbrost05

drivers/gpu/drm/xe/xe_bo.c

@@ -1055,6 +1055,7 @@ static long xe_bo_shrink_purge(struct ttm_operation_ctx *ctx,
 			       unsigned long *scanned)
 {
 	struct xe_device *xe = ttm_to_xe_device(bo->bdev);
+	struct ttm_tt *tt = bo->ttm;
 	long lret;
 
 	/* Fake move to system, without copying data. */
@@ -1079,8 +1080,10 @@ static long xe_bo_shrink_purge(struct ttm_operation_ctx *ctx,
 			      .writeback = false,
 			      .allow_move = false});
 
-	if (lret > 0)
+	if (lret > 0) {
 		xe_ttm_tt_account_subtract(xe, bo->ttm);
+		update_global_total_pages(bo->bdev, -(long)tt->num_pages);
+	}
 
 	return lret;
 }
@@ -1166,8 +1169,10 @@ long xe_bo_shrink(struct ttm_operation_ctx *ctx, struct ttm_buffer_object *bo,
 	if (needs_rpm)
 		xe_pm_runtime_put(xe);
 
-	if (lret > 0)
+	if (lret > 0) {
 		xe_ttm_tt_account_subtract(xe, tt);
+		update_global_total_pages(bo->bdev, -(long)tt->num_pages);
+	}
 
 out_unref:
 	xe_bo_put(xe_bo);