HiCache: avoid unnecessary all-reduce in check_prefetch_progress (#36425)

test/registered/unit/mem_cache/test_unified_radix_cache_unittest.py

@@ -7626,7 +7626,7 @@ class TestPrefetchCommitOrdering(CustomTestCase):
         cache._check_hybrid_prefetch_result.return_value = 8
         cache.cache_controller.prefetch_tokens_occupied = 100
         cache.prefetch_loaded_tokens_by_reqid = {}
-        cache.can_terminate_prefetch.return_value = True
+        cache._can_terminate_prefetch.return_value = True
         cache.pp_rank = 0
 
         order = mock.MagicMock()
@@ -7799,7 +7799,7 @@ class TestUnifiedRadixPrefetchCorruption(CustomTestCase):
         operation.hash_value = hashes
 
         with (
-            mock.patch.object(cache, "can_terminate_prefetch", return_value=True),
+            mock.patch.object(cache, "_can_terminate_prefetch", return_value=True),
             # Isolate the drop-release branch under test from the hybrid-sync
             # step: treat the whole fetched prefix as usable so the insert runs.
             mock.patch.object(