81 lines · cpp
1// Synthetic benchmark for __tsan_read/write{1,2,4,8}.2// As compared to mini_bench_local/shared.cc this benchmark passes through3// deduplication logic (ContainsSameAccess).4// First argument is access size (1, 2, 4, 8). Second optional arg switches5// from writes to reads.6 7#include <pthread.h>8#include <stdlib.h>9#include <stdio.h>10#include <unistd.h>11#include <linux/futex.h>12#include <sys/syscall.h>13#include <sys/time.h>14 15template<typename T, bool write>16void* thread(void *arg) {17 const int kSize = 2 << 10;18 static volatile long data[kSize];19 static volatile long turn;20 const int kRepeat = 1 << 17;21 const int id = !!arg;22 for (int i = 0; i < kRepeat; i++) {23 for (;;) {24 int t = __atomic_load_n(&turn, __ATOMIC_ACQUIRE);25 if (t == id)26 break;27 syscall(SYS_futex, &turn, FUTEX_WAIT, t, 0, 0, 0);28 }29 for (int j = 0; j < kSize; j++) {30 if (write) {31 ((volatile T*)&data[j])[0] = 1;32 ((volatile T*)&data[j])[sizeof(T) == 8 ? 0 : 1] = 1;33 } else {34 T v0 = ((volatile T*)&data[j])[0];35 T v1 = ((volatile T*)&data[j])[sizeof(T) == 8 ? 0 : 1];36 (void)v0;37 (void)v1;38 }39 }40 __atomic_store_n(&turn, 1 - id, __ATOMIC_RELEASE);41 syscall(SYS_futex, &turn, FUTEX_WAKE, 0, 0, 0, 0);42 }43 return 0;44}45 46template<typename T, bool write>47void test() {48 pthread_t th;49 pthread_create(&th, 0, thread<T, write>, (void*)1);50 thread<T, write>(0);51 pthread_join(th, 0); 52}53 54template<bool write>55void testw(int size) {56 switch (size) {57 case 1: return test<char, write>();58 case 2: return test<short, write>();59 case 4: return test<int, write>();60 case 8: return test<long long, write>();61 }62}63 64int main(int argc, char** argv) {65 int size = 8;66 bool write = true;67 if (argc > 1) {68 size = atoi(argv[1]);69 if (size != 1 && size != 2 && size != 4 && size != 8)70 size = 8;71 }72 if (argc > 2)73 write = false;74 printf("%s%d\n", write ? "write" : "read", size);75 if (write)76 testw<true>(size);77 else78 testw<false>(size);79 return 0;80}81