[LTP] [PATCH v3 2/2] Refactor exit_group01 using new API

Andrea Cervesato
2023-09-08T10:23:58Z

From: Andrea Cervesato <andrea.cervesato@suse.com>

We provided a different approach to exit_group() testing, spawning
multiple threads inside the child and checking if they get killed with
the parent process.

Signed-off-by: Andrea Cervesato <andrea.cervesato@suse.com>
---
Added thread_alive() function that checks existance of running threads, instead
of using kill(tid, 0) method.
tst_gettid() usage

testcases/kernel/syscalls/exit_group/Makefile | 2 +
.../kernel/syscalls/exit_group/exit_group01.c | 160 ++++++++++++------
2 files changed, 111 insertions(+), 51 deletions(-)

diff --git a/testcases/kernel/syscalls/exit_group/Makefile b/testcases/kernel/syscalls/exit_group/Makefile
index 1273a4e9c..adbac3c51 100644
--- a/testcases/kernel/syscalls/exit_group/Makefile
+++ b/testcases/kernel/syscalls/exit_group/Makefile
@@ -3,6 +3,8 @@

top_srcdir ?= ../../../..

+exit_group01: CFLAGS+=-pthread
+
include $(top_srcdir)/include/mk/testcases.mk

include $(top_srcdir)/include/mk/generic_leaf_target.mk
diff --git a/testcases/kernel/syscalls/exit_group/exit_group01.c b/testcases/kernel/syscalls/exit_group/exit_group01.c
index 5bf5b0218..2fcfff2f2 100644
--- a/testcases/kernel/syscalls/exit_group/exit_group01.c
+++ b/testcases/kernel/syscalls/exit_group/exit_group01.c
@@ -1,68 +1,126 @@
-/******************************************************************************
- * Copyright (c) Crackerjack Project., 2007 *
- * Ported to LTP by Manas Kumar Nayak <maknayak@in.ibm.com> *
- * Copyright (C) 2015 Cyril Hrubis <chrubis@suse.cz> *
- * *
- * This program is free software; you can redistribute it and/or modify *
- * it under the terms of the GNU General Public License as published by *
- * the Free Software Foundation; either version 2 of the License, or *
- * (at your option) any later version. *
- * *
- * This program is distributed in the hope that it will be useful, *
- * but WITHOUT ANY WARRANTY; without even the implied warranty of *
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See *
- * the GNU General Public License for more details. *
- * *
- * You should have received a copy of the GNU General Public License *
- * along with this program; if not, write to the Free Software Foundation, *
- * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA *
- * *
- ******************************************************************************/
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) Crackerjack Project., 2007
+ * Ported to LTP by Manas Kumar Nayak <maknayak@in.ibm.com>
+ * Copyright (c) 2015 Linux Test Project
+ * Copyright (C) 2015 Cyril Hrubis <chrubis@suse.cz>
+ * Copyright (C) 2023 SUSE LLC Andrea Cervesato <andrea.cervesato@suse.com>
+ */

-#include <stdio.h>
-#include <errno.h>
-#include <linux/unistd.h>
-#include <sys/wait.h>
+/*\
+ * [Description]
+ *
+ * This test checks if exit_group() correctly ends a spawned child and all its
+ * running threads.
+ */

-#include "test.h"
-#include "safe_macros.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include "tst_safe_pthread.h"
+#include "tst_test.h"
#include "lapi/syscalls.h"

-char *TCID = "exit_group01";
-int testno;
-int TST_TOTAL = 1;
+#define THREADS_NUM 10
+
+static pid_t *tids;

-static void verify_exit_group(void)
+static void thread_alive(const int tid)
{
- pid_t cpid, w;
- int status;
+ char folder[128];
+ struct stat sb;
+ char state;

- cpid = fork();
- if (cpid == -1)
- tst_brkm(TFAIL | TERRNO, NULL, "fork failed");
+ snprintf(folder, sizeof(folder), "/proc/%i/stat", tid);

- if (cpid == 0) {
- TEST(tst_syscall(__NR_exit_group, 4));
- } else {
- w = SAFE_WAIT(NULL, &status);
-
- if (WIFEXITED(status) && (WEXITSTATUS(status) == 4)) {
- tst_resm(TPASS, "exit_group() succeeded");
- } else {
- tst_resm(TFAIL | TERRNO,
- "exit_group() failed (wait status = %d)", w);
+ for (;;) {
+ if (stat(folder, &sb) == -1) {
+ if (errno != ENOENT)
+ tst_brk(TBROK | TERRNO, "stat() error");
+
+ break;
+ }
+
+ SAFE_FILE_SCANF(folder, "%*i %*s %c", &state);
+
+ if (state != 'S') {
+ tst_brk(TBROK,
+ "Thread %d is supposed to sleep but it's in '%c' state",
+ tid, state);
}
+
+ usleep(1000);
}
}

-int main(int ac, char **av)
+static void *worker(void *arg)
{
- int lc;
+ int i = *((int *)arg);

- tst_parse_opts(ac, av, NULL, NULL);
+ tids[i] = tst_gettid();

- for (lc = 0; TEST_LOOPING(lc); lc++)
- verify_exit_group();
+ TST_CHECKPOINT_WAKE(0);
+ pause();

- tst_exit();
+ return arg;
}
+
+static void spawn_threads(void)
+{
+ pthread_t threads[THREADS_NUM];
+
+ for (int i = 0; i < THREADS_NUM; i++) {
+ SAFE_PTHREAD_CREATE(&threads[i], NULL, worker, (void *)&i);
+ TST_CHECKPOINT_WAIT(0);
+
+ /* wait for paused thread */
+ TST_PROCESS_STATE_WAIT(tids[i], 'S', 0);
+ }
+}
+
+static void run(void)
+{
+ pid_t pid;
+ int status;
+
+ pid = SAFE_FORK();
+ if (!pid) {
+ spawn_threads();
+
+ TEST(tst_syscall(__NR_exit_group, 4));
+ if (TST_RET == -1)
+ tst_brk(TBROK | TERRNO, "exit_group() error");
+
+ return;
+ }
+
+ SAFE_WAITPID(pid, &status, 0);
+
+ for (int i = 0; i < THREADS_NUM; i++)
+ thread_alive(tids[i]);
+
+ TST_EXP_EXPR(WIFEXITED(status) && WEXITSTATUS(status) == 4,
+ "exit_group() succeeded");
+}
+
+static void setup(void)
+{
+ tids = SAFE_MMAP(
+ NULL,
+ sizeof(pid_t) * THREADS_NUM,
+ PROT_READ | PROT_WRITE,
+ MAP_SHARED | MAP_ANONYMOUS,
+ -1, 0);
+}
+
+static void cleanup(void)
+{
+ SAFE_MUNMAP(tids, sizeof(pid_t) * THREADS_NUM);
+}
+
+static struct tst_test test = {
+ .setup = setup,
+ .cleanup = cleanup,
+ .test_all = run,
+ .forks_child = 1,
+ .needs_checkpoints = 1,
+};
--
2.35.3