117 lines · c
1// SPDX-License-Identifier: GPL-2.02 3#define _GNU_SOURCE4#include <errno.h>5#include <linux/types.h>6#include <poll.h>7#include <signal.h>8#include <stdbool.h>9#include <stdio.h>10#include <stdlib.h>11#include <string.h>12#include <syscall.h>13#include <sys/wait.h>14#include <unistd.h>15 16#include "pidfd.h"17#include "../kselftest.h"18 19static bool timeout;20 21static void handle_alarm(int sig)22{23 timeout = true;24}25 26int main(int argc, char **argv)27{28 struct pollfd fds;29 int iter, nevents;30 int nr_iterations = 10000;31 32 fds.events = POLLIN;33 34 if (argc > 2)35 ksft_exit_fail_msg("Unexpected command line argument\n");36 37 if (argc == 2) {38 nr_iterations = atoi(argv[1]);39 if (nr_iterations <= 0)40 ksft_exit_fail_msg("invalid input parameter %s\n",41 argv[1]);42 }43 44 ksft_print_msg("running pidfd poll test for %d iterations\n",45 nr_iterations);46 47 for (iter = 0; iter < nr_iterations; iter++) {48 int pidfd;49 int child_pid = fork();50 51 if (child_pid < 0) {52 if (errno == EAGAIN) {53 iter--;54 continue;55 }56 ksft_exit_fail_msg(57 "%s - failed to fork a child process\n",58 strerror(errno));59 }60 61 if (child_pid == 0) {62 /* Child process just sleeps for a min and exits */63 sleep(60);64 exit(EXIT_SUCCESS);65 }66 67 /* Parent kills the child and waits for its death */68 pidfd = sys_pidfd_open(child_pid, 0);69 if (pidfd < 0)70 ksft_exit_fail_msg("%s - pidfd_open failed\n",71 strerror(errno));72 73 /* Setup 3 sec alarm - plenty of time */74 if (signal(SIGALRM, handle_alarm) == SIG_ERR)75 ksft_exit_fail_msg("%s - signal failed\n",76 strerror(errno));77 alarm(3);78 79 /* Send SIGKILL to the child */80 if (sys_pidfd_send_signal(pidfd, SIGKILL, NULL, 0))81 ksft_exit_fail_msg("%s - pidfd_send_signal failed\n",82 strerror(errno));83 84 /* Wait for the death notification */85 fds.fd = pidfd;86 nevents = poll(&fds, 1, -1);87 88 /* Check for error conditions */89 if (nevents < 0)90 ksft_exit_fail_msg("%s - poll failed\n",91 strerror(errno));92 93 if (nevents != 1)94 ksft_exit_fail_msg("unexpected poll result: %d\n",95 nevents);96 97 if (!(fds.revents & POLLIN))98 ksft_exit_fail_msg(99 "unexpected event type received: 0x%x\n",100 fds.revents);101 102 if (timeout)103 ksft_exit_fail_msg(104 "death notification wait timeout\n");105 106 close(pidfd);107 /* Wait for child to prevent zombies */108 if (waitpid(child_pid, NULL, 0) < 0)109 ksft_exit_fail_msg("%s - waitpid failed\n",110 strerror(errno));111 112 }113 114 ksft_test_result_pass("pidfd poll test: pass\n");115 ksft_exit_pass();116}117