8324828: Avoid multiple search of reserved regions during splitting

Reviewed-by: stuefe, jsjolen

src/hotspot/share/cds/metaspaceShared.cpp

@@ -1327,6 +1327,9 @@ char* MetaspaceShared::reserve_address_space_for_archives(FileMapInfo* static_ma
       release_reserved_spaces(total_space_rs, archive_space_rs, class_space_rs);
       return nullptr;
     }
+    // NMT: fix up the space tags
+    MemTracker::record_virtual_memory_type(archive_space_rs.base(), mtClassShared);
+    MemTracker::record_virtual_memory_type(class_space_rs.base(), mtClass);
   } else {
     if (use_archive_base_addr && base_address != nullptr) {
       total_space_rs = ReservedSpace(total_range_size, archive_space_alignment,
@@ -1356,16 +1359,13 @@ char* MetaspaceShared::reserve_address_space_for_archives(FileMapInfo* static_ma
                                                  (size_t)archive_space_alignment);
     class_space_rs = total_space_rs.last_part(ccs_begin_offset);
     MemTracker::record_virtual_memory_split_reserved(total_space_rs.base(), total_space_rs.size(),
-                                                     ccs_begin_offset);
+                                                     ccs_begin_offset, mtClassShared, mtClass);
   }
   assert(is_aligned(archive_space_rs.base(), archive_space_alignment), "Sanity");
   assert(is_aligned(archive_space_rs.size(), archive_space_alignment), "Sanity");
   assert(is_aligned(class_space_rs.base(), class_space_alignment), "Sanity");
   assert(is_aligned(class_space_rs.size(), class_space_alignment), "Sanity");
 
-  // NMT: fix up the space tags
-  MemTracker::record_virtual_memory_type(archive_space_rs.base(), mtClassShared);
-  MemTracker::record_virtual_memory_type(class_space_rs.base(), mtClass);
 
   return archive_space_rs.base();
 

src/hotspot/share/nmt/memTracker.hpp

@@ -175,12 +175,12 @@ class MemTracker : AllStatic {
   //
   // The two new memory regions will be both registered under stack and
   //  memory flags of the original region.
-  static inline void record_virtual_memory_split_reserved(void* addr, size_t size, size_t split) {
+  static inline void record_virtual_memory_split_reserved(void* addr, size_t size, size_t split, MEMFLAGS flag, MEMFLAGS split_flag) {
     assert_post_init();
     if (!enabled()) return;
     if (addr != nullptr) {
       ThreadCritical tc;
-      VirtualMemoryTracker::split_reserved_region((address)addr, size, split);
+      VirtualMemoryTracker::split_reserved_region((address)addr, size, split, flag, split_flag);
     }
   }
 

src/hotspot/share/nmt/virtualMemoryTracker.cpp

@@ -560,7 +560,7 @@ bool VirtualMemoryTracker::remove_released_region(address addr, size_t size) {
 // Given an existing memory mapping registered with NMT, split the mapping in
 //  two. The newly created two mappings will be registered under the call
 //  stack and the memory flags of the original section.
-bool VirtualMemoryTracker::split_reserved_region(address addr, size_t size, size_t split) {
+bool VirtualMemoryTracker::split_reserved_region(address addr, size_t size, size_t split, MEMFLAGS flag, MEMFLAGS split_flag) {
 
   ReservedMemoryRegion  rgn(addr, size);
   ReservedMemoryRegion* reserved_rgn = _reserved_regions->find(rgn);
@@ -576,8 +576,8 @@ bool VirtualMemoryTracker::split_reserved_region(address addr, size_t size, size
   log_debug(nmt)("Split region \'%s\' (" INTPTR_FORMAT ", " SIZE_FORMAT ")  with size " SIZE_FORMAT,
                 name, p2i(rgn.base()), rgn.size(), split);
   // Now, create two new regions.
-  add_reserved_region(addr, split, original_stack, original_flags);
-  add_reserved_region(addr + split, size - split, original_stack, original_flags);
+  add_reserved_region(addr, split, original_stack, flag);
+  add_reserved_region(addr + split, size - split, original_stack, split_flag);
 
   return true;
 }

src/hotspot/share/nmt/virtualMemoryTracker.hpp

@@ -390,7 +390,7 @@ class VirtualMemoryTracker : AllStatic {
   // Given an existing memory mapping registered with NMT, split the mapping in
   //  two. The newly created two mappings will be registered under the call
   //  stack and the memory flags of the original section.
-  static bool split_reserved_region(address addr, size_t size, size_t split);
+  static bool split_reserved_region(address addr, size_t size, size_t split, MEMFLAGS flag, MEMFLAGS split_flag);
 
   // Walk virtual memory data structure for creating baseline, etc.
   static bool walk_virtual_memory(VirtualMemoryWalker* walker);