fix test assert for total malloc amounts

Author: roberttoyonaga

test/hotspot/gtest/nmt/test_nmt_chunk_accounting.cpp

@@ -98,7 +98,7 @@ TEST_VM(NMTChunkAccounting, standard_chunks) {
     return;
   }
   static const size_t GROW_SIZE = Chunk::size;
-  static const size_t NUM_ALLOCS = 64;
+  static const size_t NUM_ALLOCS = 512;
   CountersSnapshot after_grow;
   Arena::suspend_chunk_pool_cleaning(true);
   {
@@ -119,9 +119,9 @@ TEST_VM(NMTChunkAccounting, standard_chunks) {
     // mtTest should grow matching arena size.
     EXPECT_EQ(arena.size_in_bytes(), expected_arena_size);
     EXPECT_EQ(after_grow.mtTest_arena_size, arena.size_in_bytes());
-    // Total malloc counters should have grown too.
-    EXPECT_GE(after_grow.all_mallocs_size, baseline.all_mallocs_size + expected_arena_size / 2);
-    EXPECT_GE(after_grow.all_mallocs_count, baseline.all_mallocs_count + NUM_ALLOCS / 2);
+    // Total malloc counters should have grown too, but ensure we account for free chunks pre-existing in the pool.
+    EXPECT_GE(after_grow.all_mallocs_size, baseline.all_mallocs_size + expected_arena_size / 2 -  baseline.mtChunk_malloc_size);
+    EXPECT_GE(after_grow.all_mallocs_count, baseline.all_mallocs_count + NUM_ALLOCS / 2 - baseline.mtChunk_malloc_count);
   }
 
   const CountersSnapshot after_destroy = take_snapshot();