1 files changed, 151 insertions, 0 deletions
diff --git a/lib/tsan/rtl/tsan_platform_posix.cc b/lib/tsan/rtl/tsan_platform_posix.cc
new file mode 100644
index 000000000000..90476cbc5fd5
--- /dev/null
+++ b/lib/tsan/rtl/tsan_platform_posix.cc
@@ -0,0 +1,151 @@
+//===-- tsan_platform_posix.cc --------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of ThreadSanitizer (TSan), a race detector.
+//
+// POSIX-specific code.
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_common/sanitizer_platform.h"
+#if SANITIZER_POSIX
+
+#include "sanitizer_common/sanitizer_common.h"
+#include "sanitizer_common/sanitizer_libc.h"
+#include "sanitizer_common/sanitizer_procmaps.h"
+#include "tsan_platform.h"
+#include "tsan_rtl.h"
+
+namespace __tsan {
+
+#ifndef SANITIZER_GO
+void InitializeShadowMemory() {
+  // Map memory shadow.
+  uptr shadow =
+      (uptr)MmapFixedNoReserve(ShadowBeg(), ShadowEnd() - ShadowBeg(),
+                               "shadow");
+  if (shadow != ShadowBeg()) {
+    Printf("FATAL: ThreadSanitizer can not mmap the shadow memory\n");
+    Printf("FATAL: Make sure to compile with -fPIE and "
+               "to link with -pie (%p, %p).\n", shadow, ShadowBeg());
+    Die();
+  }
+  // This memory range is used for thread stacks and large user mmaps.
+  // Frequently a thread uses only a small part of stack and similarly
+  // a program uses a small part of large mmap. On some programs
+  // we see 20% memory usage reduction without huge pages for this range.
+  // FIXME: don't use constants here.
+#if defined(__x86_64__)
+  const uptr kMadviseRangeBeg  = 0x7f0000000000ull;
+  const uptr kMadviseRangeSize = 0x010000000000ull;
+#elif defined(__mips64)
+  const uptr kMadviseRangeBeg  = 0xff00000000ull;
+  const uptr kMadviseRangeSize = 0x0100000000ull;
+#elif defined(__aarch64__)
+  uptr kMadviseRangeBeg = 0;
+  uptr kMadviseRangeSize = 0;
+  if (vmaSize == 39) {
+    kMadviseRangeBeg  = 0x7d00000000ull;
+    kMadviseRangeSize = 0x0300000000ull;
+  } else if (vmaSize == 42) {
+    kMadviseRangeBeg  = 0x3f000000000ull;
+    kMadviseRangeSize = 0x01000000000ull;
+  } else {
+    DCHECK(0);
+  }
+#elif defined(__powerpc64__)
+  uptr kMadviseRangeBeg = 0;
+  uptr kMadviseRangeSize = 0;
+  if (vmaSize == 44) {
+    kMadviseRangeBeg  = 0x0f60000000ull;
+    kMadviseRangeSize = 0x0010000000ull;
+  } else if (vmaSize == 46) {
+    kMadviseRangeBeg  = 0x3f0000000000ull;
+    kMadviseRangeSize = 0x010000000000ull;
+  } else {
+    DCHECK(0);
+  }
+#endif
+  NoHugePagesInRegion(MemToShadow(kMadviseRangeBeg),
+                      kMadviseRangeSize * kShadowMultiplier);
+  // Meta shadow is compressing and we don't flush it,
+  // so it makes sense to mark it as NOHUGEPAGE to not over-allocate memory.
+  // On one program it reduces memory consumption from 5GB to 2.5GB.
+  NoHugePagesInRegion(MetaShadowBeg(), MetaShadowEnd() - MetaShadowBeg());
+  if (common_flags()->use_madv_dontdump)
+    DontDumpShadowMemory(ShadowBeg(), ShadowEnd() - ShadowBeg());
+  DPrintf("memory shadow: %zx-%zx (%zuGB)\n",
+      ShadowBeg(), ShadowEnd(),
+      (ShadowEnd() - ShadowBeg()) >> 30);
+
+  // Map meta shadow.
+  uptr meta_size = MetaShadowEnd() - MetaShadowBeg();
+  uptr meta =
+      (uptr)MmapFixedNoReserve(MetaShadowBeg(), meta_size, "meta shadow");
+  if (meta != MetaShadowBeg()) {
+    Printf("FATAL: ThreadSanitizer can not mmap the shadow memory\n");
+    Printf("FATAL: Make sure to compile with -fPIE and "
+               "to link with -pie (%p, %p).\n", meta, MetaShadowBeg());
+    Die();
+  }
+  if (common_flags()->use_madv_dontdump)
+    DontDumpShadowMemory(meta, meta_size);
+  DPrintf("meta shadow: %zx-%zx (%zuGB)\n",
+      meta, meta + meta_size, meta_size >> 30);
+
+  InitializeShadowMemoryPlatform();
+}
+
+static void ProtectRange(uptr beg, uptr end) {
+  CHECK_LE(beg, end);
+  if (beg == end)
+    return;
+  if (beg != (uptr)MmapNoAccess(beg, end - beg)) {
+    Printf("FATAL: ThreadSanitizer can not protect [%zx,%zx]\n", beg, end);
+    Printf("FATAL: Make sure you are not using unlimited stack\n");
+    Die();
+  }
+}
+
+void CheckAndProtect() {
+  // Ensure that the binary is indeed compiled with -pie.
+  MemoryMappingLayout proc_maps(true);
+  uptr p, end, prot;
+  while (proc_maps.Next(&p, &end, 0, 0, 0, &prot)) {
+    if (IsAppMem(p))
+      continue;
+    if (p >= HeapMemEnd() &&
+        p < HeapEnd())
+      continue;
+    if (prot == 0)  // Zero page or mprotected.
+      continue;
+    if (p >= VdsoBeg())  // vdso
+      break;
+    Printf("FATAL: ThreadSanitizer: unexpected memory mapping %p-%p\n", p, end);
+    Die();
+  }
+
+  ProtectRange(LoAppMemEnd(), ShadowBeg());
+  ProtectRange(ShadowEnd(), MetaShadowBeg());
+#ifdef TSAN_MID_APP_RANGE
+  ProtectRange(MetaShadowEnd(), MidAppMemBeg());
+  ProtectRange(MidAppMemEnd(), TraceMemBeg());
+#else
+  ProtectRange(MetaShadowEnd(), TraceMemBeg());
+#endif
+  // Memory for traces is mapped lazily in MapThreadTrace.
+  // Protect the whole range for now, so that user does not map something here.
+  ProtectRange(TraceMemBeg(), TraceMemEnd());
+  ProtectRange(TraceMemEnd(), HeapMemBeg());
+  ProtectRange(HeapEnd(), HiAppMemBeg());
+}
+#endif
+
+}  // namespace __tsan
+
+#endif  // SANITIZER_POSIX