[compiler-rt] r177278 - tsan: madvise(DONTNEED) shadow memory on munmap()

[Dmitry Vyukov]

Author: dvyukov
Date: Mon Mar 18 06:51:51 2013
New Revision: 177278

URL: http://llvm.org/viewvc/llvm-project?rev=177278&view=rev
Log:
tsan: madvise(DONTNEED) shadow memory on munmap()


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

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=177278&r1=177277&r2=177278&view=diff
==============================================================================
--- compiler-rt/trunk/lib/tsan/rtl/tsan_interceptors.cc (original)
+++ compiler-rt/trunk/lib/tsan/rtl/tsan_interceptors.cc Mon Mar 18 06:51:51 2013
@@ -619,6 +619,11 @@ TSAN_INTERCEPTOR(void*, mmap64, void *ad
 
 TSAN_INTERCEPTOR(int, munmap, void *addr, long_t sz) {
   SCOPED_TSAN_INTERCEPTOR(munmap, addr, sz);
+  // We are about to unmap a chunk of user memory.
+  // Mark the corresponding shadow memory as not needed.
+  uptr shadow_beg = MemToShadow((uptr)addr);
+  uptr shadow_end = MemToShadow((uptr)addr + sz);
+  FlushUnneededShadowMemory(shadow_beg, shadow_end - shadow_beg);
   int res = REAL(munmap)(addr, sz);
   return res;
 }