Changeset 275924 in webkit

Timestamp:

Apr 13, 2021, 7:19:29 PM (4 years ago)

Author:

mark.lam@apple.com

Message:

The watchdog should not fire when it's not active.
​https://bugs.webkit.org/show_bug.cgi?id=224494
rdar://76581259

Reviewed by Saam Barati and Yusuke Suzuki.

The watchdog is only active when we have entered the VM. If we haven't entered
the VM, we postpone starting the watchdog. For example, see Watchdog::enteredVM()
and Watchdog::exitedVM().

The underlying timer may still fire the NeedWatchdogCheck event after
Watchdog::stopTimer() is called. So, we need to just ignore the event if the
watchdog isn't active.

• runtime/VMTraps.cpp:

(JSC::VMTraps::handleTraps):

• runtime/Watchdog.h:

(JSC::Watchdog::isActive const):

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• runtime/VMTraps.cpp (modified) (1 diff)
• runtime/Watchdog.h (modified) (2 diffs)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2021-04-13  Mark Lam  <mark.lam@apple.com>
+
+        The watchdog should not fire when it's not active.
+        https://bugs.webkit.org/show_bug.cgi?id=224494
+        rdar://76581259
+
+        Reviewed by Saam Barati and Yusuke Suzuki.
+
+        The watchdog is only active when we have entered the VM.  If we haven't entered
+        the VM, we postpone starting the watchdog.  For example, see Watchdog::enteredVM()
+        and Watchdog::exitedVM().
+
+        The underlying timer may still fire the NeedWatchdogCheck event after
+        Watchdog::stopTimer() is called.  So, we need to just ignore the event if the
+        watchdog isn't active.
+
+        * runtime/VMTraps.cpp:
+        (JSC::VMTraps::handleTraps):
+        * runtime/Watchdog.h:
+        (JSC::Watchdog::isActive const):
+
 2021-04-13  Ross Kirsling  <ross.kirsling@sony.com>
 

trunk/Source/JavaScriptCore/runtime/VMTraps.cpp

@@ -381 +381 @@
         case NeedWatchdogCheck:
             ASSERT(vm.watchdog());
-            ASSERT(vm.entryScope->globalObject());
-            if (LIKELY(!vm.watchdog()->shouldTerminate(vm.entryScope->globalObject())))
+            if (LIKELY(!vm.watchdog()->isActive() || !vm.watchdog()->shouldTerminate(vm.entryScope->globalObject())))
                 continue;
             vm.setTerminationInProgress(true);

trunk/Source/JavaScriptCore/runtime/Watchdog.h

@@ -1 +1 @@
 /*
- * Copyright (C) 2013-2017 Apple Inc. All rights reserved.
+ * Copyright (C) 2013-2021 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -51 +51 @@
     bool shouldTerminate(JSGlobalObject*);
 
+    bool isActive() const { return m_hasEnteredVM; }
+
     bool hasTimeLimit();
     void enteredVM();