Record Chrome trace events in tcmalloc heap profiles

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 202 matching lines @@
                                       // (NULL if no need for dumping yet)
 static int   dump_count = 0;          // How many dumps so far
 static int64 last_dump_alloc = 0;     // alloc_size when did we last dump
 static int64 last_dump_free = 0;      // free_size when did we last dump
 static int64 high_water_mark = 0;     // In-use-bytes at last high-water dump
 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
 
+// Callback an appplication can use to generate its own "stacks".
+static PseudoStackGenerator pseudo_stack_generator = NULL;
+
 //----------------------------------------------------------------------
 // Profile generation
 //----------------------------------------------------------------------
 
 // 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) {
     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);
+//      bytes_written = heap_profile->FillOrderedProfile(buf, buflen - 1);
+      bytes_written = heap_profile->FillOrderedProfile2(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), "");
 
@@ skipping 111 matching lines @@
       if (inuse_bytes > high_water_mark)
         high_water_mark = inuse_bytes;
     }
   }
 }
 
 // Record an allocation in the profile.
 static void RecordAlloc(const void* ptr, size_t bytes, int skip_count) {
   // Take the stack trace outside the critical section.
   void* stack[HeapProfileTable::kMaxStackDepth];
-  int depth = HeapProfileTable::GetCallerStackTrace(skip_count + 1, stack);
+  //JAMESDEBUG this is the wrong place to do this, look deeper
+  int depth;
+  if (pseudo_stack_generator) {
+    depth = (*pseudo_stack_generator)(stack);
+  } else {
+    stack[0] = NULL;
+    depth = 1;
+  }
+//  int depth = HeapProfileTable::GetCallerStackTrace(skip_count + 1, stack);
   SpinLockHolder l(&heap_lock);
   if (is_on) {
     heap_profile->RecordAlloc(ptr, bytes, depth, stack);
     MaybeDumpProfileLocked();
   }
 }
 
 // Record a deallocation in the profile.
 static void RecordFree(const void* ptr) {
   SpinLockHolder l(&heap_lock);
@@ skipping 246 matching lines @@
 }
 
 extern "C" void HeapProfilerDumpAliveObjects(const char* filename) {
   SpinLockHolder l(&heap_lock);
 
   if (!is_on) return;
 
   heap_profile->DumpMarkedObjects(HeapProfileTable::MARK_TWO, filename);
 }
 
+extern "C" void SetPseudoStackGenerator(PseudoStackGenerator callback) {
+  SpinLockHolder l(&heap_lock);
+  pseudo_stack_generator = callback;
+}
+
 //----------------------------------------------------------------------
 // Initialization/finalization code
 //----------------------------------------------------------------------
 
 // Initialization code
 static void HeapProfilerInit() {
   // Everything after this point is for setting up the profiler based on envvar
   char fname[PATH_MAX];
   if (!GetUniquePathFromEnv(HEAPPROFILE, fname)) {
     return;
@@ skipping 14 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;