1 // RUN: %clangxx_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
2 // Regression test for https://github.com/golang/go/issues/39186
3
4 // pthread barriers are not available on OS X
5 // UNSUPPORTED: darwin
6
7 #include "java.h"
8 #include <string.h>
9
10 struct Heap {
11 uint64_t data;
12 uint64_t ready;
13 uint64_t finalized;
14 uint64_t wg;
15 pthread_barrier_t barrier_finalizer;
16 pthread_barrier_t barrier_ballast;
17 };
18
Thread1(void * p)19 void *Thread1(void *p) {
20 Heap* heap = (Heap*)p;
21 pthread_barrier_wait(&heap->barrier_finalizer);
22 __tsan_java_finalize();
23 __atomic_fetch_add(&heap->wg, 1, __ATOMIC_RELEASE);
24 __atomic_store_n(&heap->finalized, 1, __ATOMIC_RELAXED);
25 return 0;
26 }
27
Thread2(void * p)28 void *Thread2(void *p) {
29 Heap* heap = (Heap*)p;
30 pthread_barrier_wait(&heap->barrier_finalizer);
31 heap->data = 1;
32 __atomic_store_n(&heap->ready, 1, __ATOMIC_RELEASE);
33 return 0;
34 }
35
Thread3(void * p)36 void *Thread3(void *p) {
37 Heap* heap = (Heap*)p;
38 pthread_barrier_wait(&heap->barrier_finalizer);
39 while (__atomic_load_n(&heap->ready, __ATOMIC_ACQUIRE) != 1)
40 pthread_yield();
41 while (__atomic_load_n(&heap->finalized, __ATOMIC_RELAXED) != 1)
42 pthread_yield();
43 __atomic_fetch_add(&heap->wg, 1, __ATOMIC_RELEASE);
44 return 0;
45 }
46
Ballast(void * p)47 void *Ballast(void *p) {
48 Heap* heap = (Heap*)p;
49 pthread_barrier_wait(&heap->barrier_ballast);
50 return 0;
51 }
52
main()53 int main() {
54 Heap* heap = (Heap*)calloc(sizeof(Heap), 2) + 1;
55 __tsan_java_init((jptr)heap, sizeof(*heap));
56 __tsan_java_alloc((jptr)heap, sizeof(*heap));
57 // Ballast threads merely make the bug a bit easier to trigger.
58 const int kBallastThreads = 100;
59 pthread_barrier_init(&heap->barrier_finalizer, 0, 4);
60 pthread_barrier_init(&heap->barrier_ballast, 0, kBallastThreads + 1);
61 pthread_t th[3];
62 pthread_create(&th[0], 0, Thread1, heap);
63 pthread_create(&th[1], 0, Thread2, heap);
64 pthread_t ballast[kBallastThreads];
65 for (int i = 0; i < kBallastThreads; i++)
66 pthread_create(&ballast[i], 0, Ballast, heap);
67 pthread_create(&th[2], 0, Thread3, heap);
68 pthread_barrier_wait(&heap->barrier_ballast);
69 for (int i = 0; i < kBallastThreads; i++)
70 pthread_join(ballast[i], 0);
71 pthread_barrier_wait(&heap->barrier_finalizer);
72 while (__atomic_load_n(&heap->wg, __ATOMIC_ACQUIRE) != 2)
73 pthread_yield();
74 if (heap->data != 1)
75 exit(printf("no data\n"));
76 for (int i = 0; i < 3; i++)
77 pthread_join(th[i], 0);
78 pthread_barrier_destroy(&heap->barrier_ballast);
79 pthread_barrier_destroy(&heap->barrier_finalizer);
80 __tsan_java_free((jptr)heap, sizeof(*heap));
81 fprintf(stderr, "DONE\n");
82 return __tsan_java_fini();
83 }
84
85 // CHECK-NOT: WARNING: ThreadSanitizer: data race
86 // CHECK: DONE
87