Chrome.BrowserCrashDumpAttempts needs to account for multiple dumps from the same browser process.

chrome/app/breakpad_win.cc

Index: chrome/app/breakpad_win.cc
diff --git a/chrome/app/breakpad_win.cc b/chrome/app/breakpad_win.cc
index 9fc453127f3215c29f3f2f59fdc8600a7c93f43d..2a616f6ca508d7b4e36e0b8d5050c9d80ae30b49 100644
--- a/chrome/app/breakpad_win.cc
+++ b/chrome/app/breakpad_win.cc
@@ -13,6 +13,7 @@
 #include <algorithm>
 #include <vector>
 
+#include "base/atomicops.h"
 #include "base/basictypes.h"
 #include "base/base_switches.h"
 #include "base/command_line.h"
@@ -127,6 +128,7 @@ static HKEY g_browser_crash_dump_regkey = NULL;
 static const wchar_t kBrowserCrashDumpValueFormatStr[] = L"%08x-%08x";
 static const int kBrowserCrashDumpValueLength = 17;
 static wchar_t g_browser_crash_dump_value[kBrowserCrashDumpValueLength+1] = {0};
+static base::subtle::Atomic32 g_browser_crash_dump_count = 0;

[cpu_(ooo_6.6-7.5), 2013/09/04 23:29:45]

aka int32 btw

[Roger McFarlane (Chromium), 2013/09/05 13:57:53]

Yes, I know. But this communicates the intended usage.

 
 void InitBrowserCrashDumpsRegKey() {
   DCHECK(g_browser_crash_dump_regkey == NULL);
@@ -142,6 +144,7 @@ void InitBrowserCrashDumpsRegKey() {
     return;
   }
 
+  // Hold the registry key in a global for update on crash dump.
   g_browser_crash_dump_regkey = regkey.Take();
 
   // We use the current process id and the curren tick count as a (hopefully)
@@ -159,11 +162,24 @@ void InitBrowserCrashDumpsRegKey() {
 }
 
 void SendSmokeSignalForCrashDump() {
-  if (g_browser_crash_dump_regkey != NULL) {
-    base::win::RegKey regkey(g_browser_crash_dump_regkey);
-    regkey.WriteValue(g_browser_crash_dump_value, 1);
-    g_browser_crash_dump_regkey = NULL;
-  }
+  // If we're not a browser (or the registry is unavailable to us for some
+  // reason) then there's nothing to do.
+  if (g_browser_crash_dump_regkey == NULL)
+    return;
+
+  // Increment the number of crash dumps and persist it to the registry.
+  // Note that there is a race condition here: the final count could be off by
+  // one if two dumps are triggered at the same moment and the registry writes
+  // happen to be committed in the reverse order of the atomic increments.
+  // We'll live with this, as we don't want to attempt any "real" work while
+  // we may be in a crashing state.
+  base::win::RegKey regkey(g_browser_crash_dump_regkey);
+  regkey.WriteValue(
+      g_browser_crash_dump_value,
+      base::subtle::NoBarrier_AtomicIncrement(&g_browser_crash_dump_count, 1));
+
+  // Don't let regkey auto-close the key. More crash dumps may follow.
+  ignore_result(regkey.Take());
 }
 
 // Dumps the current process memory.