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// RUN: %clangxx_tsan %s -o %t
// RUN: TSAN_OPTIONS=detect_deadlocks=1 not %t 2>&1 | FileCheck %s
#include <pthread.h>
#undef NDEBUG
#include <assert.h>
#include <stdio.h>
class PaddedLock {
public:
PaddedLock() { assert(0 == pthread_mutex_init(&mu_, 0)); }
~PaddedLock() {
assert(0 == pthread_mutex_destroy(&mu_));
(void)padding_;
}
void lock() { assert(0 == pthread_mutex_lock(&mu_)); }
void unlock() { assert(0 == pthread_mutex_unlock(&mu_)); }
bool try_lock() { return 0 == pthread_mutex_trylock(&mu_); }
private:
pthread_mutex_t mu_;
char padding_[64 - sizeof(pthread_mutex_t)];
};
class LockTest {
public:
LockTest(size_t n) : n_(n), locks_(new PaddedLock[n]) { }
~LockTest() { delete [] locks_; }
void L(size_t i) {
assert(i < n_);
locks_[i].lock();
}
void U(size_t i) {
assert(i < n_);
locks_[i].unlock();
}
void *A(size_t i) {
assert(i < n_);
return &locks_[i];
}
bool T(size_t i) {
assert(i < n_);
return locks_[i].try_lock();
}
// Simple lock order onversion.
void Test1() {
fprintf(stderr, "Starting Test1\n");
// CHECK: Starting Test1
fprintf(stderr, "Expecting lock inversion: %p %p\n", A(0), A(1));
// CHECK: Expecting lock inversion: [[A1:0x[a-f0-9]*]] [[A2:0x[a-f0-9]*]]
Lock_0_1();
Lock_1_0();
// CHECK: WARNING: ThreadSanitizer: lock-order-inversion (potential deadlock)
// CHECK: path: [[M1:M[0-9]+]] => [[M2:M[0-9]+]] => [[M1]]
// CHECK: Mutex [[M1]] ([[A1]]) created at:
// CHECK: Mutex [[M2]] ([[A2]]) created at:
// CHECK-NOT: WARNING: ThreadSanitizer:
}
// Simple lock order inversion with 3 locks.
void Test2() {
fprintf(stderr, "Starting Test2\n");
// CHECK: Starting Test2
fprintf(stderr, "Expecting lock inversion: %p %p %p\n", A(0), A(1), A(2));
// CHECK: Expecting lock inversion: [[A1:0x[a-f0-9]*]] [[A2:0x[a-f0-9]*]] [[A3:0x[a-f0-9]*]]
Lock2(0, 1);
Lock2(1, 2);
Lock2(2, 0);
// CHECK: WARNING: ThreadSanitizer: lock-order-inversion (potential deadlock)
// CHECK: path: [[M1:M[0-9]+]] => [[M2:M[0-9]+]] => [[M3:M[0-9]+]] => [[M1]]
// CHECK: Mutex [[M1]] ([[A1]]) created at:
// CHECK: Mutex [[M2]] ([[A2]]) created at:
// CHECK: Mutex [[M3]] ([[A3]]) created at:
// CHECK-NOT: WARNING: ThreadSanitizer:
}
// Lock order inversion with lots of new locks created (but not used)
// between. Since the new locks are not used we should still detect the
// deadlock.
void Test3() {
fprintf(stderr, "Starting Test3\n");
// CHECK: Starting Test3
Lock_0_1();
L(2);
CreateAndDestroyManyLocks();
U(2);
Lock_1_0();
// CHECK: WARNING: ThreadSanitizer: lock-order-inversion (potential deadlock)
// CHECK-NOT: WARNING: ThreadSanitizer:
}
// lock l0=>l1; then create and use lots of locks; then lock l1=>l0.
// The deadlock epoch should have changed and we should not report anything.
void Test4() {
fprintf(stderr, "Starting Test4\n");
// CHECK: Starting Test4
Lock_0_1();
L(2);
CreateLockUnlockAndDestroyManyLocks();
U(2);
Lock_1_0();
// CHECK-NOT: WARNING: ThreadSanitizer:
}
void Test5() {
fprintf(stderr, "Starting Test5\n");
// CHECK: Starting Test5
RunThreads(&LockTest::Lock_0_1, &LockTest::Lock_1_0);
// CHECK: WARNING: ThreadSanitizer: lock-order-inversion
// CHECK-NOT: WARNING: ThreadSanitizer:
}
void Test6() {
fprintf(stderr, "Starting Test6\n");
// CHECK: Starting Test6
// CHECK-NOT: WARNING: ThreadSanitizer:
RunThreads(&LockTest::Lock1_Loop_0, &LockTest::Lock1_Loop_1,
&LockTest::Lock1_Loop_2);
}
void Test7() {
fprintf(stderr, "Starting Test7\n");
// CHECK: Starting Test7
L(0); T(1); U(1); U(0);
T(1); L(0); U(1); U(0);
// CHECK-NOT: WARNING: ThreadSanitizer:
fprintf(stderr, "No cycle: 0=>1\n");
// CHECK: No cycle: 0=>1
T(2); L(3); U(3); U(2);
L(3); T(2); U(3); U(2);
// CHECK-NOT: WARNING: ThreadSanitizer:
fprintf(stderr, "No cycle: 2=>3\n");
// CHECK: No cycle: 2=>3
T(4); L(5); U(4); U(5);
L(5); L(4); U(4); U(5);
// CHECK: WARNING: ThreadSanitizer: lock-order-inversion
fprintf(stderr, "Have cycle: 4=>5\n");
// CHECK: Have cycle: 4=>5
L(7); L(6); U(6); U(7);
T(6); L(7); U(6); U(7);
// CHECK: WARNING: ThreadSanitizer: lock-order-inversion
fprintf(stderr, "Have cycle: 6=>7\n");
// CHECK: Have cycle: 6=>7
}
private:
void Lock2(size_t l1, size_t l2) { L(l1); L(l2); U(l2); U(l1); }
void Lock_0_1() { Lock2(0, 1); }
void Lock_1_0() { Lock2(1, 0); }
void Lock1_Loop(size_t i, size_t n_iter) {
for (size_t it = 0; it < n_iter; it++) {
// if ((it & (it - 1)) == 0) fprintf(stderr, "%zd", i);
L(i);
U(i);
}
// fprintf(stderr, "\n");
}
void Lock1_Loop_0() { Lock1_Loop(0, 100000); }
void Lock1_Loop_1() { Lock1_Loop(1, 100000); }
void Lock1_Loop_2() { Lock1_Loop(2, 100000); }
void CreateAndDestroyManyLocks() {
PaddedLock create_many_locks_but_never_acquire[kDeadlockGraphSize];
}
void CreateLockUnlockAndDestroyManyLocks() {
PaddedLock many_locks[kDeadlockGraphSize];
for (size_t i = 0; i < kDeadlockGraphSize; i++) {
many_locks[i].lock();
many_locks[i].unlock();
}
}
// LockTest Member function callback.
struct CB {
void (LockTest::*f)();
LockTest *lt;
};
// Thread function with CB.
static void *Thread(void *param) {
CB *cb = (CB*)param;
(cb->lt->*cb->f)();
return NULL;
}
void RunThreads(void (LockTest::*f1)(), void (LockTest::*f2)(),
void (LockTest::*f3)() = 0) {
const int kNumThreads = 3;
pthread_t t[kNumThreads];
CB cb[kNumThreads] = {{f1, this}, {f2, this}, {f3, this}};
for (int i = 0; i < kNumThreads && cb[i].f; i++)
pthread_create(&t[i], 0, Thread, &cb[i]);
for (int i = 0; i < kNumThreads && cb[i].f; i++)
pthread_join(t[i], 0);
}
static const size_t kDeadlockGraphSize = 4096;
size_t n_;
PaddedLock *locks_;
};
int main() {
{ LockTest t(5); t.Test1(); }
{ LockTest t(5); t.Test2(); }
{ LockTest t(5); t.Test3(); }
{ LockTest t(5); t.Test4(); }
{ LockTest t(5); t.Test5(); }
{ LockTest t(5); t.Test6(); }
{ LockTest t(10); t.Test7(); }
fprintf(stderr, "DONE\n");
// CHECK: DONE
}
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