A small program to

tlbshoot.c

/*
 * tlbshoot.c - A program used to test SmartOS TLB shoot down.
 *
 * This program simply creates a shared memory segment of fixed size
 * attaches to the shm segment then detaches repeatedly to cause TLB
 * flushes.
 */

#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/shm.h>

#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>

#define IPCProtection   (0600)  /* access/modify by user only */
#define SHMGET_FLAGS (IPC_CREAT | IPC_EXCL | IPCProtection)

#define SHMAT_FLAGS SHM_SHARE_MMU

int main() {
	int shmid;
	size_t size = 32000000000;
	char *shm;

	/*
	 * Create the segment.
	 */
	if ((shmid = shmget(getpid(), size, SHMGET_FLAGS)) < 0) {
		perror("shmget");
		exit(1);
	}

	for (int i = 0;;i++) {
		printf("Iteration: %d\n", i);
		/*
		 * Now we attach the segment to our data space.
		 */
		if ((shm = shmat(shmid, NULL, SHMAT_FLAGS)) == (char *) -1) {
			perror("shmat");
			exit(1);
		}

		/*
		 * Detach
		 */
		if (shmdt(shm) != 0) {
			perror("shmdt");
			exit(1);
		}
	}

	return 0;
}