Add the reason in heap profiler dumps.

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 207 matching lines @@
 static int64 last_dump_time = 0;      // The time of the last dump
 
 static HeapProfileTable* heap_profile = NULL;  // the heap profile table
 static DeepHeapProfile* deep_profile = NULL;  // deep memory profiler
 
 //----------------------------------------------------------------------
 // Profile generation
 //----------------------------------------------------------------------
 
 // Input must be a buffer of size at least 1MB.
-static char* DoGetHeapProfileLocked(char* buf, int buflen) {
+static char* DoGetHeapProfileLocked(char* buf, int buflen, const char* reason) {

[Alexander Potapenko, 2013/05/27 08:54:44]

It's probably better to put |reason| first. I don't strongly insist on this
neither here, nor in deep-heap-profile.h

[Dai Mikurube (NOT FULLTIME), 2013/05/27 10:08:24]

Reasonable, too.  Done.

   // 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) {
     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);
+      bytes_written = deep_profile->FillOrderedProfile(buf, buflen - 1, reason);
     } else {
       bytes_written = heap_profile->FillOrderedProfile(buf, buflen - 1);
     }
     // 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));
   SpinLockHolder l(&heap_lock);
-  return DoGetHeapProfileLocked(buffer, kProfileBufferSize);
+  return DoGetHeapProfileLocked(buffer, kProfileBufferSize, NULL);

[Alexander Potapenko, 2013/05/27 08:54:44]

/*reason*/NULL

[Dai Mikurube (NOT FULLTIME), 2013/05/27 10:08:24]

Done.

 }
 
 // defined below
 static void NewHook(const void* ptr, size_t size);
 static void DeleteHook(const void* ptr);
 
 // Helper for HeapProfilerDump.
 static void DumpProfileLocked(const char* reason) {
   RAW_DCHECK(heap_lock.IsHeld(), "");
   RAW_DCHECK(is_on, "");
@@ skipping 21 matching lines @@
   }
 
   // This case may be impossible, but it's best to be safe.
   // It's safe to use the global buffer: we're protected by heap_lock.
   if (global_profiler_buffer == NULL) {
     global_profiler_buffer =
         reinterpret_cast<char*>(ProfilerMalloc(kProfileBufferSize));
   }
 
   char* profile = DoGetHeapProfileLocked(global_profiler_buffer,
-                                         kProfileBufferSize);
+                                         kProfileBufferSize, reason);
   RawWrite(fd, profile, strlen(profile));
   RawClose(fd);
 
 #if defined(TYPE_PROFILING)
   if (FLAGS_heap_profile_type_statistics) {
     snprintf(file_name, sizeof(file_name), "%s.%05d.%04d.type",
              filename_prefix, getpid(), dump_count);
     RAW_VLOG(0, "Dumping type statistics to %s", file_name);
     heap_profile->DumpTypeStatistics(file_name);
   }
@@ skipping 352 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;