Count m(un)map for each stacktrace in MemoryRegionMap instead of HeapProfileTable.

third_party/tcmalloc/chromium/src/heap-profiler.cc

 // Copyright (c) 2005, Google Inc.
 // All rights reserved.
 // 
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 // 
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
@@ skipping 139 matching lines @@
 
 static LowLevelAlloc::Arena* heap_profiler_memory;
 
 static void* ProfilerMalloc(size_t bytes) {
   return LowLevelAlloc::AllocWithArena(bytes, heap_profiler_memory);
 }
 static void ProfilerFree(void* p) {
   LowLevelAlloc::Free(p);
 }
 
-//----------------------------------------------------------------------
-// Another allocator for heap profiler's internal mmap address map
-//
-// Large amount of memory is consumed if we use an arena 'heap_profiler_memory'
-// for the internal mmap address map.  It looks like memory fragmentation
-// because of repeated allocation/deallocation in the arena.
-//
-// 'mmap_heap_profiler_memory' is a dedicated arena for the mmap address map.
-// This arena is reserved for every construction of the mmap address map, and
-// disposed after every use.
-//----------------------------------------------------------------------
-
-static LowLevelAlloc::Arena* mmap_heap_profiler_memory = NULL;
-
-static void* MMapProfilerMalloc(size_t bytes) {
-  return LowLevelAlloc::AllocWithArena(bytes, mmap_heap_profiler_memory);
-}
-static void MMapProfilerFree(void* p) {
-  LowLevelAlloc::Free(p);
-}
-
-// This function should be called from a locked scope.
-// It returns false if failed in deleting the arena.
-static bool DeleteMMapProfilerArenaIfExistsLocked() {
-  if (mmap_heap_profiler_memory == NULL) return true;
-  if (!LowLevelAlloc::DeleteArena(mmap_heap_profiler_memory)) return false;
-  mmap_heap_profiler_memory = NULL;
-  return true;
-}
-
 // We use buffers of this size in DoGetHeapProfile.
 // The size is 1 << 20 in the original google-perftools.  Changed it to
 // 5 << 20 since a larger buffer is requried for deeper profiling in Chromium.
 // The buffer is allocated only when the environment variable HEAPPROFILE is
 // specified to dump heap information.
 static const int kProfileBufferSize = 5 << 20;
 
 // This is a last-ditch buffer we use in DumpProfileLocked in case we
 // can't allocate more memory from ProfilerMalloc.  We expect this
 // will be used by HeapProfileEndWriter when the application has to
@@ skipping 27 matching lines @@
 // Input must be a buffer of size at least 1MB.
 static char* DoGetHeapProfileLocked(char* buf, int buflen) {
   // We used to be smarter about estimating the required memory and
   // then capping it to 1MB and generating the profile into that.
   if (buf == NULL || buflen < 1)
     return NULL;
 
   RAW_DCHECK(heap_lock.IsHeld(), "");
   int bytes_written = 0;
   if (is_on) {
-    if (FLAGS_mmap_profile) {
-      if (!DeleteMMapProfilerArenaIfExistsLocked()) {
-        RAW_LOG(FATAL, "Memory leak in HeapProfiler:");
-      }
-      mmap_heap_profiler_memory =
-          LowLevelAlloc::NewArena(0, LowLevelAlloc::DefaultArena());
-      heap_profile->RefreshMMapData(MMapProfilerMalloc, MMapProfilerFree);
-    }
+    HeapProfileTable::Stats const stats = heap_profile->total();
+    (void)stats;   // avoid an unused-variable warning in non-debug mode.
     if (deep_profile) {
       bytes_written = deep_profile->FillOrderedProfile(buf, buflen - 1);
     } else {
       bytes_written = heap_profile->FillOrderedProfile(buf, buflen - 1);
     }
-    if (FLAGS_mmap_profile) {
-      heap_profile->ClearMMapData();
-      if (!DeleteMMapProfilerArenaIfExistsLocked()) {
-        RAW_LOG(FATAL, "Memory leak in HeapProfiler:");
-      }
-    }
+    // FillOrderedProfile should not reduce the set of active mmap-ed regions,
+    // hence MemoryRegionMap will let us remove everything we've added above:
+    RAW_DCHECK(stats.Equivalent(heap_profile->total()), "");
+    // if this fails, we somehow removed by FillOrderedProfile
+    // more than we have added.
   }
   buf[bytes_written] = '\0';
   RAW_DCHECK(bytes_written == strlen(buf), "");
 
   return buf;
 }
 
 extern "C" char* GetHeapProfile() {
   // Use normal malloc: we return the profile to the user to free it:
   char* buffer = reinterpret_cast<char*>(malloc(kProfileBufferSize));
@@ skipping 229 matching lines @@
   // call new, and we want that to be accounted for correctly.
   MallocExtension::Initialize();
 
   if (FLAGS_only_mmap_profile) {
     FLAGS_mmap_profile = true;
   }
 
   if (FLAGS_mmap_profile) {
     // Ask MemoryRegionMap to record all mmap, mremap, and sbrk
     // call stack traces of at least size kMaxStackDepth:
-    MemoryRegionMap::Init(HeapProfileTable::kMaxStackDepth);
+    MemoryRegionMap::Init(HeapProfileTable::kMaxStackDepth,
+                          /* use_buckets */ true);
   }
 
   if (FLAGS_mmap_log) {
     // Install our hooks to do the logging:
     RAW_CHECK(MallocHook::AddMmapHook(&MmapHook), "");
     RAW_CHECK(MallocHook::AddMremapHook(&MremapHook), "");
     RAW_CHECK(MallocHook::AddMunmapHook(&MunmapHook), "");
     RAW_CHECK(MallocHook::AddSbrkHook(&SbrkHook), "");
   }
 
   heap_profiler_memory =
     LowLevelAlloc::NewArena(0, LowLevelAlloc::DefaultArena());
 
   // Reserve space now for the heap profiler, so we can still write a
   // heap profile even if the application runs out of memory.
   global_profiler_buffer =
       reinterpret_cast<char*>(ProfilerMalloc(kProfileBufferSize));
 
   heap_profile = new(ProfilerMalloc(sizeof(HeapProfileTable)))
-                   HeapProfileTable(ProfilerMalloc, ProfilerFree);
+      HeapProfileTable(ProfilerMalloc, ProfilerFree, FLAGS_mmap_profile);
 
   last_dump_alloc = 0;
   last_dump_free = 0;
   high_water_mark = 0;
   last_dump_time = 0;
 
   if (FLAGS_deep_heap_profile) {
     // Initialize deep memory profiler
     RAW_VLOG(0, "[%d] Starting a deep memory profiler", getpid());
     deep_profile = new(ProfilerMalloc(sizeof(DeepHeapProfile)))
@@ skipping 51 matching lines @@
 
   if (deep_profile) {
     // free deep memory profiler
     deep_profile->~DeepHeapProfile();
     ProfilerFree(deep_profile);
     deep_profile = NULL;
   }
 
   // free profile
   heap_profile->~HeapProfileTable();
-  if (!DeleteMMapProfilerArenaIfExistsLocked()) {
-    RAW_LOG(FATAL, "Memory leak in HeapProfiler:");
-  }
   ProfilerFree(heap_profile);
   heap_profile = NULL;
 
   // free output-buffer memory
   ProfilerFree(global_profiler_buffer);
 
   // free prefix
   ProfilerFree(filename_prefix);
   filename_prefix = NULL;
 
@@ skipping 76 matching lines @@
 
 // class used for finalization -- dumps the heap-profile at program exit
 struct HeapProfileEndWriter {
   ~HeapProfileEndWriter() { HeapProfilerDump("Exiting"); }
 };
 
 // We want to make sure tcmalloc is up and running before starting the profiler
 static const TCMallocGuard tcmalloc_initializer;
 REGISTER_MODULE_INITIALIZER(heapprofiler, HeapProfilerInit());
 static HeapProfileEndWriter heap_profile_end_writer;