Puthikorn Voravootivat | 84d5afc | 2020-01-14 14:50:19 -0800 | [diff] [blame^] | 1 | |
| 2 | // This is required on Mac OS X for getting PRI* macros #defined. |
| 3 | #define __STDC_FORMAT_MACROS |
| 4 | |
| 5 | #include <assert.h> |
| 6 | #include <fcntl.h> |
| 7 | #include <inttypes.h> |
| 8 | #include <stdint.h> |
| 9 | #include <stdio.h> |
| 10 | #include <stdlib.h> |
| 11 | #include <string.h> |
| 12 | #include <sys/mount.h> |
| 13 | #include <sys/mman.h> |
| 14 | #include <sys/time.h> |
| 15 | #include <sys/stat.h> |
| 16 | #include <sys/wait.h> |
| 17 | #include <time.h> |
| 18 | #include <unistd.h> |
| 19 | |
| 20 | const size_t mem_size = (1 << 30)/4; |
| 21 | const int toggles = 540000; |
| 22 | |
| 23 | const uint64_t pte_pattern = 0xb7d02580000003C5; |
| 24 | char *g_mem; |
| 25 | |
| 26 | // Pick a random page in the memory region. |
| 27 | uint8_t* pick_addr(uint8_t* area_base, uint64_t mem_size) { |
| 28 | size_t offset = (rand() << 12) % mem_size; |
| 29 | return area_base + offset; |
| 30 | } |
| 31 | |
| 32 | class Timer { |
| 33 | struct timeval start_time_; |
| 34 | |
| 35 | public: |
| 36 | Timer() { |
| 37 | // Note that we use gettimeofday() (with microsecond resolution) |
| 38 | // rather than clock_gettime() (with nanosecond resolution) so |
| 39 | // that this works on Mac OS X, because OS X doesn't provide |
| 40 | // clock_gettime() and we don't really need nanosecond resolution. |
| 41 | int rc = gettimeofday(&start_time_, NULL); |
| 42 | assert(rc == 0); |
| 43 | } |
| 44 | |
| 45 | double get_diff() { |
| 46 | struct timeval end_time; |
| 47 | int rc = gettimeofday(&end_time, NULL); |
| 48 | assert(rc == 0); |
| 49 | return (end_time.tv_sec - start_time_.tv_sec |
| 50 | + (double) (end_time.tv_usec - start_time_.tv_usec) / 1e6); |
| 51 | } |
| 52 | |
| 53 | void print_iters(uint64_t iterations) { |
| 54 | double total_time = get_diff(); |
| 55 | double iter_time = total_time / iterations; |
| 56 | printf("%.3fns,%g,%" PRIu64, |
| 57 | iter_time * 1e9, total_time, iterations); |
| 58 | } |
| 59 | }; |
| 60 | |
| 61 | uint64_t get_physical_address(uint64_t virtual_address) { |
| 62 | int fd = open("/proc/self/pagemap", O_RDONLY); |
| 63 | assert(fd >=0); |
| 64 | |
| 65 | off_t pos = lseek(fd, (virtual_address / 0x1000) * 8, SEEK_SET); |
| 66 | assert(pos >= 0); |
| 67 | uint64_t value; |
| 68 | int got = read(fd, &value, 8); |
| 69 | |
| 70 | close(fd); |
| 71 | assert(got == 8); |
| 72 | return ((value & ((1ULL << 54)-1)) * 0x1000) | |
| 73 | (virtual_address & 0xFFF); |
| 74 | } |
| 75 | |
| 76 | static int sigint = 0; |
| 77 | static void sigint_handler(int signum) { |
| 78 | sigint = 1; |
| 79 | } |
| 80 | static int sigquit = 0; |
| 81 | static void sigquit_handler(int signum) { |
| 82 | sigint = 1; |
| 83 | sigquit = 1; |
| 84 | } |
| 85 | |
| 86 | static void toggle(int iterations, int addr_count) { |
| 87 | Timer t; |
| 88 | for (int j = 0; j < iterations; j++) { |
| 89 | volatile uint32_t *addrs[addr_count]; |
| 90 | for (int a = 0; a < addr_count; a++) { |
| 91 | addrs[a] = (uint32_t *) pick_addr((uint8_t*)g_mem, mem_size); |
| 92 | //printf(" Hammering virtual address %16lx, physical address %16lx\n", |
| 93 | //(uint64_t)addrs[a], get_physical_address((uint64_t)addrs[a])); |
| 94 | } |
| 95 | |
| 96 | // TODO(wad) try the approach from github.com/CMU-SAFARI/rowhammer |
| 97 | // as it may be faster. |
| 98 | uint32_t sum = 0; |
| 99 | for (int i = 0; i < toggles; i++) { |
| 100 | for (int a = 0; a < addr_count; a++) |
| 101 | sum += *addrs[a] + 1; |
| 102 | for (int a = 0; a < addr_count; a++) |
| 103 | asm volatile("clflush (%0)" : : "r" (addrs[a]) : "memory"); |
| 104 | } |
| 105 | if (sigint) { |
| 106 | sigint = 0; |
| 107 | break; |
| 108 | } |
| 109 | } |
| 110 | t.print_iters(iterations * addr_count * toggles); |
| 111 | } |
| 112 | |
| 113 | void main_prog() { |
| 114 | g_mem = (char *) mmap(NULL, mem_size, PROT_READ | PROT_WRITE, |
| 115 | MAP_ANON | MAP_PRIVATE, -1, 0); |
| 116 | assert(g_mem != MAP_FAILED); |
| 117 | |
| 118 | // printf("clear\n"); |
| 119 | |
| 120 | //memset(g_mem, 0xff, mem_size); |
| 121 | |
| 122 | // Fill memory with pattern that resembles page tables entries. |
| 123 | // c5 03 00 00 80 25 d0 b7 |
| 124 | for (uint32_t i = 0; i < mem_size; i += 8) { |
| 125 | uint64_t* ptr = (uint64_t*)(&g_mem[i]); |
| 126 | *ptr = pte_pattern; |
| 127 | } |
| 128 | |
| 129 | Timer t; |
| 130 | int iter = 0; |
| 131 | for (;;) { |
| 132 | printf("%d,%.2fs,", iter++, t.get_diff()); |
| 133 | fflush(stdout); |
| 134 | toggle(3000, 4); |
| 135 | |
| 136 | Timer check_timer; |
| 137 | // printf("check\n"); |
| 138 | uint64_t *end = (uint64_t *) (g_mem + mem_size); |
| 139 | uint64_t *ptr; |
| 140 | int errors = 0; |
| 141 | for (ptr = (uint64_t *) g_mem; ptr < end; ptr++) { |
| 142 | uint64_t got = *ptr; |
| 143 | if (got != pte_pattern) { |
| 144 | fprintf(stderr, "error at %p (%16lx): got 0x%" PRIx64 "\n", ptr, get_physical_address((uint64_t)ptr), got); |
| 145 | fprintf(stderr, "after %.2fs\n", t.get_diff()); |
| 146 | errors++; |
| 147 | } |
| 148 | } |
| 149 | printf(",%fs", check_timer.get_diff()); |
| 150 | fflush(stdout); |
| 151 | if (errors) { |
| 152 | printf(",%d\n", errors); |
| 153 | fflush(stdout); |
| 154 | exit(1); |
| 155 | } |
| 156 | printf(",0\n"); |
| 157 | fflush(stdout); |
| 158 | if (sigquit) |
| 159 | break; |
| 160 | } |
| 161 | } |
| 162 | |
| 163 | |
| 164 | int main(int argc, char **argv) { |
| 165 | // In case we are running as PID 1, we fork() a subprocess to run |
| 166 | // the test in. Otherwise, if process 1 exits or crashes, this will |
| 167 | // cause a kernel panic (which can cause a reboot or just obscure |
| 168 | // log output and prevent console scrollback from working). |
| 169 | // Output should look like: |
| 170 | // [iteration #],[relative start offset in sec],[itertime in ns],[total time in s],[iteration count],[check time in s],[error count] |
| 171 | signal(SIGINT, &sigint_handler); |
| 172 | signal(SIGQUIT, &sigquit_handler); |
| 173 | int pid = fork(); |
| 174 | if (pid == 0) { |
| 175 | main_prog(); |
| 176 | _exit(1); |
| 177 | } |
| 178 | |
| 179 | int status; |
| 180 | int sec = argc == 2 ? atoi(argv[1]) : 60*60; |
| 181 | while (sec--) { |
| 182 | if (sigint) { |
| 183 | sigint = 0; |
| 184 | kill(pid, SIGINT); |
| 185 | if (sigquit) |
| 186 | break; |
| 187 | } |
| 188 | if (waitpid(pid, &status, WNOHANG) == pid) { |
| 189 | printf("** exited with status %i (0x%x)\n", status, status); |
| 190 | exit(status); |
| 191 | } |
| 192 | sleep(1); |
| 193 | } |
| 194 | kill(pid, SIGQUIT); |
| 195 | sleep(1); |
| 196 | kill(pid, SIGKILL); |
| 197 | // Let init reap. |
| 198 | return 0; |
| 199 | } |