[llvm-commits] [compiler-rt] r168987 - in /compiler-rt/trunk/lib/tsan/rtl: tsan_flags.h tsan_interceptors.cc

[Dmitry Vyukov]

Author: dvyukov
Date: Fri Nov 30 00:50:15 2012
New Revision: 168987

URL: http://llvm.org/viewvc/llvm-project?rev=168987&view=rev
Log:
tsan: intercept mlock() because of the kernel bug

Modified:
    compiler-rt/trunk/lib/tsan/rtl/tsan_flags.h
    compiler-rt/trunk/lib/tsan/rtl/tsan_interceptors.cc

Modified: compiler-rt/trunk/lib/tsan/rtl/tsan_flags.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/tsan/rtl/tsan_flags.h?rev=168987&r1=168986&r2=168987&view=diff
==============================================================================
--- compiler-rt/trunk/lib/tsan/rtl/tsan_flags.h (original)
+++ compiler-rt/trunk/lib/tsan/rtl/tsan_flags.h Fri Nov 30 00:50:15 2012
@@ -52,7 +52,7 @@
   // Write logs to "log_path.pid".
   // The special values are "stdout" and "stderr".
   // The default is "stderr".
-  const char *log_path;  
+  const char *log_path;
   // Sleep in main thread before exiting for that many ms
   // (useful to catch "at exit" races).
   int atexit_sleep_ms;

Modified: compiler-rt/trunk/lib/tsan/rtl/tsan_interceptors.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/tsan/rtl/tsan_interceptors.cc?rev=168987&r1=168986&r2=168987&view=diff
==============================================================================
--- compiler-rt/trunk/lib/tsan/rtl/tsan_interceptors.cc (original)
+++ compiler-rt/trunk/lib/tsan/rtl/tsan_interceptors.cc Fri Nov 30 00:50:15 2012
@@ -1349,6 +1349,35 @@
   return REAL(gettimeofday)(tv, tz);
 }
 
+// Linux kernel has a bug that leads to kernel deadlock if a process
+// maps TBs of memory and then calls mlock().
+static void MlockIsUnsupported() {
+  static atomic_uint8_t printed;
+  if (atomic_exchange(&printed, 1, memory_order_relaxed))
+    return;
+  Printf("INFO: ThreadSanitizer ignores mlock/mlockall/munlock/munlockall\n");
+}
+
+TSAN_INTERCEPTOR(int, mlock, const void *addr, uptr len) {
+  MlockIsUnsupported();
+  return 0;
+}
+
+TSAN_INTERCEPTOR(int, munlock, const void *addr, uptr len) {
+  MlockIsUnsupported();
+  return 0;
+}
+
+TSAN_INTERCEPTOR(int, mlockall, int flags) {
+  MlockIsUnsupported();
+  return 0;
+}
+
+TSAN_INTERCEPTOR(int, munlockall, void) {
+  MlockIsUnsupported();
+  return 0;
+}
+
 namespace __tsan {
 
 void ProcessPendingSignals(ThreadState *thr) {
@@ -1526,6 +1555,11 @@
   TSAN_INTERCEPT(nanosleep);
   TSAN_INTERCEPT(gettimeofday);
 
+  TSAN_INTERCEPT(mlock);
+  TSAN_INTERCEPT(munlock);
+  TSAN_INTERCEPT(mlockall);
+  TSAN_INTERCEPT(munlockall);
+
   atexit_ctx = new(internal_alloc(MBlockAtExit, sizeof(AtExitContext)))
       AtExitContext();