blob: 180d87b79934ff0161d231c645e3f330a8a15f80 [file] [log] [blame]
//===-- tsan_interface_atomic.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.
//
//===----------------------------------------------------------------------===//
// ThreadSanitizer atomic operations are based on C++11/C1x standards.
// For background see C++11 standard. A slightly older, publically
// available draft of the standard (not entirely up-to-date, but close enough
// for casual browsing) is available here:
// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3242.pdf
// The following page contains more background information:
// http://www.hpl.hp.com/personal/Hans_Boehm/c++mm/
#include "sanitizer_common/sanitizer_placement_new.h"
#include "sanitizer_common/sanitizer_stacktrace.h"
#include "tsan_interface_atomic.h"
#include "tsan_flags.h"
#include "tsan_rtl.h"
using namespace __tsan; // NOLINT
#define SCOPED_ATOMIC(func, ...) \
const uptr callpc = (uptr)__builtin_return_address(0); \
uptr pc = __sanitizer::StackTrace::GetCurrentPc(); \
mo = ConvertOrder(mo); \
mo = flags()->force_seq_cst_atomics ? (morder)mo_seq_cst : mo; \
ThreadState *const thr = cur_thread(); \
AtomicStatInc(thr, sizeof(*a), mo, StatAtomic##func); \
ScopedAtomic sa(thr, callpc, a, mo, __FUNCTION__); \
return Atomic##func(thr, pc, __VA_ARGS__); \
/**/
// Some shortcuts.
typedef __tsan_memory_order morder;
typedef __tsan_atomic8 a8;
typedef __tsan_atomic16 a16;
typedef __tsan_atomic32 a32;
typedef __tsan_atomic64 a64;
typedef __tsan_atomic128 a128;
const morder mo_relaxed = __tsan_memory_order_relaxed;
const morder mo_consume = __tsan_memory_order_consume;
const morder mo_acquire = __tsan_memory_order_acquire;
const morder mo_release = __tsan_memory_order_release;
const morder mo_acq_rel = __tsan_memory_order_acq_rel;
const morder mo_seq_cst = __tsan_memory_order_seq_cst;
class ScopedAtomic {
public:
ScopedAtomic(ThreadState *thr, uptr pc, const volatile void *a,
morder mo, const char *func)
: thr_(thr) {
CHECK_EQ(thr_->in_rtl, 0);
ProcessPendingSignals(thr);
FuncEntry(thr_, pc);
DPrintf("#%d: %s(%p, %d)\n", thr_->tid, func, a, mo);
thr_->in_rtl++;
}
~ScopedAtomic() {
thr_->in_rtl--;
CHECK_EQ(thr_->in_rtl, 0);
FuncExit(thr_);
}
private:
ThreadState *thr_;
};
static void AtomicStatInc(ThreadState *thr, uptr size, morder mo, StatType t) {
StatInc(thr, StatAtomic);
StatInc(thr, t);
StatInc(thr, size == 1 ? StatAtomic1
: size == 2 ? StatAtomic2
: size == 4 ? StatAtomic4
: size == 8 ? StatAtomic8
: StatAtomic16);
StatInc(thr, mo == mo_relaxed ? StatAtomicRelaxed
: mo == mo_consume ? StatAtomicConsume
: mo == mo_acquire ? StatAtomicAcquire
: mo == mo_release ? StatAtomicRelease
: mo == mo_acq_rel ? StatAtomicAcq_Rel
: StatAtomicSeq_Cst);
}
static bool IsLoadOrder(morder mo) {
return mo == mo_relaxed || mo == mo_consume
|| mo == mo_acquire || mo == mo_seq_cst;
}
static bool IsStoreOrder(morder mo) {
return mo == mo_relaxed || mo == mo_release || mo == mo_seq_cst;
}
static bool IsReleaseOrder(morder mo) {
return mo == mo_release || mo == mo_acq_rel || mo == mo_seq_cst;
}
static bool IsAcquireOrder(morder mo) {
return mo == mo_consume || mo == mo_acquire
|| mo == mo_acq_rel || mo == mo_seq_cst;
}
static bool IsAcqRelOrder(morder mo) {
return mo == mo_acq_rel || mo == mo_seq_cst;
}
static morder ConvertOrder(morder mo) {
if (mo > (morder)100500) {
mo = morder(mo - 100500);
if (mo == morder(1 << 0))
mo = mo_relaxed;
else if (mo == morder(1 << 1))
mo = mo_consume;
else if (mo == morder(1 << 2))
mo = mo_acquire;
else if (mo == morder(1 << 3))
mo = mo_release;
else if (mo == morder(1 << 4))
mo = mo_acq_rel;
else if (mo == morder(1 << 5))
mo = mo_seq_cst;
}
CHECK_GE(mo, mo_relaxed);
CHECK_LE(mo, mo_seq_cst);
return mo;
}
template<typename T> T func_xchg(volatile T *v, T op) {
T res = __sync_lock_test_and_set(v, op);
// __sync_lock_test_and_set does not contain full barrier.
__sync_synchronize();
return res;
}
template<typename T> T func_add(volatile T *v, T op) {
return __sync_fetch_and_add(v, op);
}
template<typename T> T func_sub(volatile T *v, T op) {
return __sync_fetch_and_sub(v, op);
}
template<typename T> T func_and(volatile T *v, T op) {
return __sync_fetch_and_and(v, op);
}
template<typename T> T func_or(volatile T *v, T op) {
return __sync_fetch_and_or(v, op);
}
template<typename T> T func_xor(volatile T *v, T op) {
return __sync_fetch_and_xor(v, op);
}
template<typename T> T func_nand(volatile T *v, T op) {
// clang does not support __sync_fetch_and_nand.
T cmp = *v;
for (;;) {
T newv = ~(cmp & op);
T cur = __sync_val_compare_and_swap(v, cmp, newv);
if (cmp == cur)
return cmp;
cmp = cur;
}
}
template<typename T> T func_cas(volatile T *v, T cmp, T xch) {
return __sync_val_compare_and_swap(v, cmp, xch);
}
// clang does not support 128-bit atomic ops.
// Atomic ops are executed under tsan internal mutex,
// here we assume that the atomic variables are not accessed
// from non-instrumented code.
#ifndef __GCC_HAVE_SYNC_COMPARE_AND_SWAP_16
a128 func_xchg(volatile a128 *v, a128 op) {
a128 cmp = *v;
*v = op;
return cmp;
}
a128 func_add(volatile a128 *v, a128 op) {
a128 cmp = *v;
*v = cmp + op;
return cmp;
}
a128 func_sub(volatile a128 *v, a128 op) {
a128 cmp = *v;
*v = cmp - op;
return cmp;
}
a128 func_and(volatile a128 *v, a128 op) {
a128 cmp = *v;
*v = cmp & op;
return cmp;
}
a128 func_or(volatile a128 *v, a128 op) {
a128 cmp = *v;
*v = cmp | op;
return cmp;
}
a128 func_xor(volatile a128 *v, a128 op) {
a128 cmp = *v;
*v = cmp ^ op;
return cmp;
}
a128 func_nand(volatile a128 *v, a128 op) {
a128 cmp = *v;
*v = ~(cmp & op);
return cmp;
}
a128 func_cas(volatile a128 *v, a128 cmp, a128 xch) {
a128 cur = *v;
if (cur == cmp)
*v = xch;
return cur;
}
#endif
template<typename T>
static int SizeLog() {
if (sizeof(T) <= 1)
return kSizeLog1;
else if (sizeof(T) <= 2)
return kSizeLog2;
else if (sizeof(T) <= 4)
return kSizeLog4;
else
return kSizeLog8;
// For 16-byte atomics we also use 8-byte memory access,
// this leads to false negatives only in very obscure cases.
}
template<typename T>
static T AtomicLoad(ThreadState *thr, uptr pc, const volatile T *a,
morder mo) {
CHECK(IsLoadOrder(mo));
// This fast-path is critical for performance.
// Assume the access is atomic.
if (!IsAcquireOrder(mo) && sizeof(T) <= sizeof(a)) {
MemoryReadAtomic(thr, pc, (uptr)a, SizeLog<T>());
return *a; // as if atomic
}
SyncVar *s = CTX()->synctab.GetOrCreateAndLock(thr, pc, (uptr)a, false);
AcquireImpl(thr, pc, &s->clock);
T v = *a;
s->mtx.ReadUnlock();
__sync_synchronize();
MemoryReadAtomic(thr, pc, (uptr)a, SizeLog<T>());
return v;
}
template<typename T>
static void AtomicStore(ThreadState *thr, uptr pc, volatile T *a, T v,
morder mo) {
CHECK(IsStoreOrder(mo));
MemoryWriteAtomic(thr, pc, (uptr)a, SizeLog<T>());
// This fast-path is critical for performance.
// Assume the access is atomic.
// Strictly saying even relaxed store cuts off release sequence,
// so must reset the clock.
if (!IsReleaseOrder(mo) && sizeof(T) <= sizeof(a)) {
*a = v; // as if atomic
return;
}
__sync_synchronize();
SyncVar *s = CTX()->synctab.GetOrCreateAndLock(thr, pc, (uptr)a, true);
thr->fast_state.IncrementEpoch();
// Can't increment epoch w/o writing to the trace as well.
TraceAddEvent(thr, thr->fast_state, EventTypeMop, 0);
ReleaseImpl(thr, pc, &s->clock);
*a = v;
s->mtx.Unlock();
// Trainling memory barrier to provide sequential consistency
// for Dekker-like store-load synchronization.
__sync_synchronize();
}
template<typename T, T (*F)(volatile T *v, T op)>
static T AtomicRMW(ThreadState *thr, uptr pc, volatile T *a, T v, morder mo) {
MemoryWriteAtomic(thr, pc, (uptr)a, SizeLog<T>());
SyncVar *s = 0;
if (mo != mo_relaxed) {
s = CTX()->synctab.GetOrCreateAndLock(thr, pc, (uptr)a, true);
thr->fast_state.IncrementEpoch();
// Can't increment epoch w/o writing to the trace as well.
TraceAddEvent(thr, thr->fast_state, EventTypeMop, 0);
if (IsAcqRelOrder(mo))
AcquireReleaseImpl(thr, pc, &s->clock);
else if (IsReleaseOrder(mo))
ReleaseImpl(thr, pc, &s->clock);
else if (IsAcquireOrder(mo))
AcquireImpl(thr, pc, &s->clock);
}
v = F(a, v);
if (s)
s->mtx.Unlock();
return v;
}
template<typename T>
static T AtomicExchange(ThreadState *thr, uptr pc, volatile T *a, T v,
morder mo) {
return AtomicRMW<T, func_xchg>(thr, pc, a, v, mo);
}
template<typename T>
static T AtomicFetchAdd(ThreadState *thr, uptr pc, volatile T *a, T v,
morder mo) {
return AtomicRMW<T, func_add>(thr, pc, a, v, mo);
}
template<typename T>
static T AtomicFetchSub(ThreadState *thr, uptr pc, volatile T *a, T v,
morder mo) {
return AtomicRMW<T, func_sub>(thr, pc, a, v, mo);
}
template<typename T>
static T AtomicFetchAnd(ThreadState *thr, uptr pc, volatile T *a, T v,
morder mo) {
return AtomicRMW<T, func_and>(thr, pc, a, v, mo);
}
template<typename T>
static T AtomicFetchOr(ThreadState *thr, uptr pc, volatile T *a, T v,
morder mo) {
return AtomicRMW<T, func_or>(thr, pc, a, v, mo);
}
template<typename T>
static T AtomicFetchXor(ThreadState *thr, uptr pc, volatile T *a, T v,
morder mo) {
return AtomicRMW<T, func_xor>(thr, pc, a, v, mo);
}
template<typename T>
static T AtomicFetchNand(ThreadState *thr, uptr pc, volatile T *a, T v,
morder mo) {
return AtomicRMW<T, func_nand>(thr, pc, a, v, mo);
}
template<typename T>
static bool AtomicCAS(ThreadState *thr, uptr pc,
volatile T *a, T *c, T v, morder mo, morder fmo) {
(void)fmo; // Unused because llvm does not pass it yet.
MemoryWriteAtomic(thr, pc, (uptr)a, SizeLog<T>());
SyncVar *s = 0;
if (mo != mo_relaxed) {
s = CTX()->synctab.GetOrCreateAndLock(thr, pc, (uptr)a, true);
thr->fast_state.IncrementEpoch();
// Can't increment epoch w/o writing to the trace as well.
TraceAddEvent(thr, thr->fast_state, EventTypeMop, 0);
if (IsAcqRelOrder(mo))
AcquireReleaseImpl(thr, pc, &s->clock);
else if (IsReleaseOrder(mo))
ReleaseImpl(thr, pc, &s->clock);
else if (IsAcquireOrder(mo))
AcquireImpl(thr, pc, &s->clock);
}
T cc = *c;
T pr = func_cas(a, cc, v);
if (s)
s->mtx.Unlock();
if (pr == cc)
return true;
*c = pr;
return false;
}
template<typename T>
static T AtomicCAS(ThreadState *thr, uptr pc,
volatile T *a, T c, T v, morder mo, morder fmo) {
AtomicCAS(thr, pc, a, &c, v, mo, fmo);
return c;
}
static void AtomicFence(ThreadState *thr, uptr pc, morder mo) {
// FIXME(dvyukov): not implemented.
__sync_synchronize();
}
a8 __tsan_atomic8_load(const volatile a8 *a, morder mo) {
SCOPED_ATOMIC(Load, a, mo);
}
a16 __tsan_atomic16_load(const volatile a16 *a, morder mo) {
SCOPED_ATOMIC(Load, a, mo);
}
a32 __tsan_atomic32_load(const volatile a32 *a, morder mo) {
SCOPED_ATOMIC(Load, a, mo);
}
a64 __tsan_atomic64_load(const volatile a64 *a, morder mo) {
SCOPED_ATOMIC(Load, a, mo);
}
#if __TSAN_HAS_INT128
a128 __tsan_atomic128_load(const volatile a128 *a, morder mo) {
SCOPED_ATOMIC(Load, a, mo);
}
#endif
void __tsan_atomic8_store(volatile a8 *a, a8 v, morder mo) {
SCOPED_ATOMIC(Store, a, v, mo);
}
void __tsan_atomic16_store(volatile a16 *a, a16 v, morder mo) {
SCOPED_ATOMIC(Store, a, v, mo);
}
void __tsan_atomic32_store(volatile a32 *a, a32 v, morder mo) {
SCOPED_ATOMIC(Store, a, v, mo);
}
void __tsan_atomic64_store(volatile a64 *a, a64 v, morder mo) {
SCOPED_ATOMIC(Store, a, v, mo);
}
#if __TSAN_HAS_INT128
void __tsan_atomic128_store(volatile a128 *a, a128 v, morder mo) {
SCOPED_ATOMIC(Store, a, v, mo);
}
#endif
a8 __tsan_atomic8_exchange(volatile a8 *a, a8 v, morder mo) {
SCOPED_ATOMIC(Exchange, a, v, mo);
}
a16 __tsan_atomic16_exchange(volatile a16 *a, a16 v, morder mo) {
SCOPED_ATOMIC(Exchange, a, v, mo);
}
a32 __tsan_atomic32_exchange(volatile a32 *a, a32 v, morder mo) {
SCOPED_ATOMIC(Exchange, a, v, mo);
}
a64 __tsan_atomic64_exchange(volatile a64 *a, a64 v, morder mo) {
SCOPED_ATOMIC(Exchange, a, v, mo);
}
#if __TSAN_HAS_INT128
a128 __tsan_atomic128_exchange(volatile a128 *a, a128 v, morder mo) {
SCOPED_ATOMIC(Exchange, a, v, mo);
}
#endif
a8 __tsan_atomic8_fetch_add(volatile a8 *a, a8 v, morder mo) {
SCOPED_ATOMIC(FetchAdd, a, v, mo);
}
a16 __tsan_atomic16_fetch_add(volatile a16 *a, a16 v, morder mo) {
SCOPED_ATOMIC(FetchAdd, a, v, mo);
}
a32 __tsan_atomic32_fetch_add(volatile a32 *a, a32 v, morder mo) {
SCOPED_ATOMIC(FetchAdd, a, v, mo);
}
a64 __tsan_atomic64_fetch_add(volatile a64 *a, a64 v, morder mo) {
SCOPED_ATOMIC(FetchAdd, a, v, mo);
}
#if __TSAN_HAS_INT128
a128 __tsan_atomic128_fetch_add(volatile a128 *a, a128 v, morder mo) {
SCOPED_ATOMIC(FetchAdd, a, v, mo);
}
#endif
a8 __tsan_atomic8_fetch_sub(volatile a8 *a, a8 v, morder mo) {
SCOPED_ATOMIC(FetchSub, a, v, mo);
}
a16 __tsan_atomic16_fetch_sub(volatile a16 *a, a16 v, morder mo) {
SCOPED_ATOMIC(FetchSub, a, v, mo);
}
a32 __tsan_atomic32_fetch_sub(volatile a32 *a, a32 v, morder mo) {
SCOPED_ATOMIC(FetchSub, a, v, mo);
}
a64 __tsan_atomic64_fetch_sub(volatile a64 *a, a64 v, morder mo) {
SCOPED_ATOMIC(FetchSub, a, v, mo);
}
#if __TSAN_HAS_INT128
a128 __tsan_atomic128_fetch_sub(volatile a128 *a, a128 v, morder mo) {
SCOPED_ATOMIC(FetchSub, a, v, mo);
}
#endif
a8 __tsan_atomic8_fetch_and(volatile a8 *a, a8 v, morder mo) {
SCOPED_ATOMIC(FetchAnd, a, v, mo);
}
a16 __tsan_atomic16_fetch_and(volatile a16 *a, a16 v, morder mo) {
SCOPED_ATOMIC(FetchAnd, a, v, mo);
}
a32 __tsan_atomic32_fetch_and(volatile a32 *a, a32 v, morder mo) {
SCOPED_ATOMIC(FetchAnd, a, v, mo);
}
a64 __tsan_atomic64_fetch_and(volatile a64 *a, a64 v, morder mo) {
SCOPED_ATOMIC(FetchAnd, a, v, mo);
}
#if __TSAN_HAS_INT128
a128 __tsan_atomic128_fetch_and(volatile a128 *a, a128 v, morder mo) {
SCOPED_ATOMIC(FetchAnd, a, v, mo);
}
#endif
a8 __tsan_atomic8_fetch_or(volatile a8 *a, a8 v, morder mo) {
SCOPED_ATOMIC(FetchOr, a, v, mo);
}
a16 __tsan_atomic16_fetch_or(volatile a16 *a, a16 v, morder mo) {
SCOPED_ATOMIC(FetchOr, a, v, mo);
}
a32 __tsan_atomic32_fetch_or(volatile a32 *a, a32 v, morder mo) {
SCOPED_ATOMIC(FetchOr, a, v, mo);
}
a64 __tsan_atomic64_fetch_or(volatile a64 *a, a64 v, morder mo) {
SCOPED_ATOMIC(FetchOr, a, v, mo);
}
#if __TSAN_HAS_INT128
a128 __tsan_atomic128_fetch_or(volatile a128 *a, a128 v, morder mo) {
SCOPED_ATOMIC(FetchOr, a, v, mo);
}
#endif
a8 __tsan_atomic8_fetch_xor(volatile a8 *a, a8 v, morder mo) {
SCOPED_ATOMIC(FetchXor, a, v, mo);
}
a16 __tsan_atomic16_fetch_xor(volatile a16 *a, a16 v, morder mo) {
SCOPED_ATOMIC(FetchXor, a, v, mo);
}
a32 __tsan_atomic32_fetch_xor(volatile a32 *a, a32 v, morder mo) {
SCOPED_ATOMIC(FetchXor, a, v, mo);
}
a64 __tsan_atomic64_fetch_xor(volatile a64 *a, a64 v, morder mo) {
SCOPED_ATOMIC(FetchXor, a, v, mo);
}
#if __TSAN_HAS_INT128
a128 __tsan_atomic128_fetch_xor(volatile a128 *a, a128 v, morder mo) {
SCOPED_ATOMIC(FetchXor, a, v, mo);
}
#endif
a8 __tsan_atomic8_fetch_nand(volatile a8 *a, a8 v, morder mo) {
SCOPED_ATOMIC(FetchNand, a, v, mo);
}
a16 __tsan_atomic16_fetch_nand(volatile a16 *a, a16 v, morder mo) {
SCOPED_ATOMIC(FetchNand, a, v, mo);
}
a32 __tsan_atomic32_fetch_nand(volatile a32 *a, a32 v, morder mo) {
SCOPED_ATOMIC(FetchNand, a, v, mo);
}
a64 __tsan_atomic64_fetch_nand(volatile a64 *a, a64 v, morder mo) {
SCOPED_ATOMIC(FetchNand, a, v, mo);
}
#if __TSAN_HAS_INT128
a128 __tsan_atomic128_fetch_nand(volatile a128 *a, a128 v, morder mo) {
SCOPED_ATOMIC(FetchNand, a, v, mo);
}
#endif
int __tsan_atomic8_compare_exchange_strong(volatile a8 *a, a8 *c, a8 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
int __tsan_atomic16_compare_exchange_strong(volatile a16 *a, a16 *c, a16 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
int __tsan_atomic32_compare_exchange_strong(volatile a32 *a, a32 *c, a32 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
int __tsan_atomic64_compare_exchange_strong(volatile a64 *a, a64 *c, a64 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
#if __TSAN_HAS_INT128
int __tsan_atomic128_compare_exchange_strong(volatile a128 *a, a128 *c, a128 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
#endif
int __tsan_atomic8_compare_exchange_weak(volatile a8 *a, a8 *c, a8 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
int __tsan_atomic16_compare_exchange_weak(volatile a16 *a, a16 *c, a16 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
int __tsan_atomic32_compare_exchange_weak(volatile a32 *a, a32 *c, a32 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
int __tsan_atomic64_compare_exchange_weak(volatile a64 *a, a64 *c, a64 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
#if __TSAN_HAS_INT128
int __tsan_atomic128_compare_exchange_weak(volatile a128 *a, a128 *c, a128 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
#endif
a8 __tsan_atomic8_compare_exchange_val(volatile a8 *a, a8 c, a8 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
a16 __tsan_atomic16_compare_exchange_val(volatile a16 *a, a16 c, a16 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
a32 __tsan_atomic32_compare_exchange_val(volatile a32 *a, a32 c, a32 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
a64 __tsan_atomic64_compare_exchange_val(volatile a64 *a, a64 c, a64 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
#if __TSAN_HAS_INT128
a128 __tsan_atomic128_compare_exchange_val(volatile a128 *a, a128 c, a128 v,
morder mo, morder fmo) {
SCOPED_ATOMIC(CAS, a, c, v, mo, fmo);
}
#endif
void __tsan_atomic_thread_fence(morder mo) {
char* a = 0;
SCOPED_ATOMIC(Fence, mo);
}
void __tsan_atomic_signal_fence(morder mo) {
}