| 1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| 2 | /* |
| 3 | * Verify that a single TB spin-loop is properly invalidated, |
| 4 | * releasing the thread from the spin-loop. |
| 5 | */ |
| 6 | |
| 7 | #include <assert.h> |
| 8 | #include <sys/mman.h> |
| 9 | #include <pthread.h> |
| 10 | #include <stdint.h> |
| 11 | #include <stdbool.h> |
| 12 | #include <unistd.h> |
| 13 | #include <sched.h> |
| 14 | |
| 15 | |
| 16 | #ifdef __x86_64__ |
| 17 | #define READY 0x000047c6 /* movb $0,0(%rdi) */ |
| 18 | #define LOOP 0xfceb9090 /* 1: nop*2; jmp 1b */ |
| 19 | #define RETURN 0x909090c3 /* ret; nop*3 */ |
| 20 | #define NOP 0x90909090 /* nop*4 */ |
| 21 | #elif defined(__aarch64__) |
| 22 | #define READY 0x3900001f /* strb wzr,[x0] */ |
| 23 | #define LOOP 0x14000000 /* b . */ |
| 24 | #define RETURN 0xd65f03c0 /* ret */ |
| 25 | #define NOP 0xd503201f /* nop */ |
| 26 | #elif defined(__riscv) |
| 27 | #define READY 0x00050023 /* sb zero, (a0) */ |
| 28 | #define LOOP 0x0000006f /* jal zero, #0 */ |
| 29 | #define RETURN 0x00008067 /* jalr zero, ra, 0 */ |
| 30 | #define NOP 0x00000013 /* nop */ |
| 31 | #endif |
| 32 | |
| 33 | |
| 34 | int main() |
| 35 | { |
| 36 | #ifdef READY |
| 37 | int tmp; |
| 38 | pthread_t thread_id; |
| 39 | bool hold = true; |
| 40 | uint32_t *buf; |
| 41 | |
| 42 | buf = mmap(NULL, 3 * sizeof(uint32_t), |
| 43 | PROT_READ | PROT_WRITE | PROT_EXEC, |
| 44 | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); |
| 45 | assert(buf != MAP_FAILED); |
| 46 | |
| 47 | buf[0] = READY; |
| 48 | buf[1] = LOOP; |
| 49 | buf[2] = RETURN; |
| 50 | |
| 51 | alarm(2); |
| 52 | |
| 53 | tmp = pthread_create(&thread_id, NULL, (void *(*)(void *))buf, &hold); |
| 54 | assert(tmp == 0); |
| 55 | |
| 56 | while (hold) { |
| 57 | sched_yield(); |
| 58 | } |
| 59 | |
| 60 | buf[1] = NOP; |
| 61 | __builtin___clear_cache(&buf[1], &buf[2]); |
| 62 | |
| 63 | tmp = pthread_join(thread_id, NULL); |
| 64 | assert(tmp == 0); |
| 65 | #endif |
| 66 | return 0; |
| 67 | } |