Retro68/gcc/libsanitizer/tsan/tsan_platform_posix.cc
2017-04-10 13:32:00 +02:00

123 lines
4.3 KiB
C++

//===-- tsan_platform_posix.cc --------------------------------------------===//
//
// 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(kShadowBeg, kShadowEnd - kShadowBeg, "shadow");
if (shadow != kShadowBeg) {
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, kShadowBeg);
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__)
const uptr kMadviseRangeBeg = 0x7e00000000ull;
const uptr kMadviseRangeSize = 0x0100000000ull;
#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(kMetaShadowBeg, kMetaShadowEnd - kMetaShadowBeg);
if (common_flags()->use_madv_dontdump)
DontDumpShadowMemory(kShadowBeg, kShadowEnd - kShadowBeg);
DPrintf("memory shadow: %zx-%zx (%zuGB)\n",
kShadowBeg, kShadowEnd,
(kShadowEnd - kShadowBeg) >> 30);
// Map meta shadow.
uptr meta_size = kMetaShadowEnd - kMetaShadowBeg;
uptr meta =
(uptr)MmapFixedNoReserve(kMetaShadowBeg, meta_size, "meta shadow");
if (meta != kMetaShadowBeg) {
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, kMetaShadowBeg);
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 >= kHeapMemEnd &&
p < HeapEnd())
continue;
if (prot == 0) // Zero page or mprotected.
continue;
if (p >= kVdsoBeg) // vdso
break;
Printf("FATAL: ThreadSanitizer: unexpected memory mapping %p-%p\n", p, end);
Die();
}
ProtectRange(kLoAppMemEnd, kShadowBeg);
ProtectRange(kShadowEnd, kMetaShadowBeg);
ProtectRange(kMetaShadowEnd, kTraceMemBeg);
// Memory for traces is mapped lazily in MapThreadTrace.
// Protect the whole range for now, so that user does not map something here.
ProtectRange(kTraceMemBeg, kTraceMemEnd);
ProtectRange(kTraceMemEnd, kHeapMemBeg);
ProtectRange(HeapEnd(), kHiAppMemBeg);
}
#endif
} // namespace __tsan
#endif // SANITIZER_POSIX