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/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Verify that a single TB spin-loop is properly invalidated,
* releasing the thread from the spin-loop.
*/
#include <assert.h>
#include <sys/mman.h>
#include <pthread.h>
#include <stdint.h>
#include <stdbool.h>
#include <unistd.h>
#include <sched.h>
#ifdef __x86_64__
#define READY 0x000047c6 /* movb $0,0(%rdi) */
#define LOOP 0xfceb9090 /* 1: nop*2; jmp 1b */
#define RETURN 0x909090c3 /* ret; nop*3 */
#define NOP 0x90909090 /* nop*4 */
#elif defined(__aarch64__)
#define READY 0x3900001f /* strb wzr,[x0] */
#define LOOP 0x14000000 /* b . */
#define RETURN 0xd65f03c0 /* ret */
#define NOP 0xd503201f /* nop */
#elif defined(__riscv)
#define READY 0x00050023 /* sb zero, (a0) */
#define LOOP 0x0000006f /* jal zero, #0 */
#define RETURN 0x00008067 /* jalr zero, ra, 0 */
#define NOP 0x00000013 /* nop */
#endif
int main()
{
#ifdef READY
int tmp;
pthread_t thread_id;
bool hold = true;
uint32_t *buf;
buf = mmap(NULL, 3 * sizeof(uint32_t),
PROT_READ | PROT_WRITE | PROT_EXEC,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
assert(buf != MAP_FAILED);
buf[0] = READY;
buf[1] = LOOP;
buf[2] = RETURN;
alarm(2);
tmp = pthread_create(&thread_id, NULL, (void *(*)(void *))buf, &hold);
assert(tmp == 0);
while (hold) {
sched_yield();
}
buf[1] = NOP;
__builtin___clear_cache(&buf[1], &buf[2]);
tmp = pthread_join(thread_id, NULL);
assert(tmp == 0);
#endif
return 0;
}
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