[Isolates] RegExpStack and memory allocation limits (statics #6)

src/platform-linux.cc

Index: src/platform-linux.cc
===================================================================
--- src/platform-linux.cc	(revision 5002)
+++ src/platform-linux.cc	(working copy)
@@ -72,6 +72,9 @@
 }
 
 
+static Mutex* limit_mutex = NULL;
+
+
 void OS::Setup() {
   // Seed the random number generator.
   // Convert the current time to a 64-bit integer first, before converting it
@@ -80,6 +83,7 @@
   // call this setup code within the same millisecond.
   uint64_t seed = static_cast<uint64_t>(TimeCurrentMillis());
   srandom(static_cast<unsigned int>(seed));
+  limit_mutex = CreateMutex();
 }
 
 
@@ -215,6 +219,9 @@
 
 
 static void UpdateAllocatedSpaceLimits(void* address, int size) {
+  ASSERT(limit_mutex != NULL);
+  ScopedLock lock(limit_mutex);
+
   lowest_ever_allocated = Min(lowest_ever_allocated, address);
   highest_ever_allocated =
       Max(highest_ever_allocated,