[LTP] [PATCH v5 0/2] Rewrite exit_group01 test

[LTP] [PATCH v5 0/2] Rewrite exit_group01 test

[Andrea Cervesato]

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

exit_group01 test has been completely rewritten and tst_gettid() has been added
to support missing gettid() syscall from GLIBC

Andrea Cervesato (2):
  Add tst_gettid wrapper around gettid syscall
  Refactor exit_group01 using new API

 include/tst_pid.h                             |   8 +
 lib/tst_pid.c                                 |   5 +
 testcases/kernel/syscalls/exit_group/Makefile |   2 +
 .../kernel/syscalls/exit_group/exit_group01.c | 161 ++++++++++++------
 4 files changed, 125 insertions(+), 51 deletions(-)

-- 
2.35.3


-- 
Mailing list info: https://lists.linux.it/listinfo/ltp

[LTP] [PATCH v5 1/2] Add tst_gettid wrapper around gettid syscall

[Andrea Cervesato]

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

Signed-off-by: Andrea Cervesato <andrea.cervesato@suse.com>
---
 include/tst_pid.h | 8 ++++++++
 lib/tst_pid.c     | 5 +++++
 2 files changed, 13 insertions(+)

diff --git a/include/tst_pid.h b/include/tst_pid.h
index 774c845ce..951138abc 100644
--- a/include/tst_pid.h
+++ b/include/tst_pid.h
@@ -50,4 +50,12 @@ static inline int tst_get_free_pids(void (*cleanup_fn)(void))
  */
 pid_t tst_getpid(void);
 
+/*
+ * Direct gettid() syscall. Some glibc versions cache gettid() return value
+ * which can cause confusing issues for example in processes created by
+ * direct clone() syscall (without using the glibc wrapper). Use this function
+ * whenever the current process may be a thread of the main test process.
+ */
+pid_t tst_gettid(void);
+
 #endif /* TST_PID_H__ */
diff --git a/lib/tst_pid.c b/lib/tst_pid.c
index cfaa5db36..4e9dc7a52 100644
--- a/lib/tst_pid.c
+++ b/lib/tst_pid.c
@@ -166,3 +166,8 @@ pid_t tst_getpid(void)
 {
 	return syscall(SYS_getpid);
 }
+
+pid_t tst_gettid(void)
+{
+	return syscall(SYS_gettid);
+}
-- 
2.35.3


-- 
Mailing list info: https://lists.linux.it/listinfo/ltp

[LTP] [PATCH v5 2/2] Refactor exit_group01 using new API

[Andrea Cervesato]

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>
---
 testcases/kernel/syscalls/exit_group/Makefile |   2 +
 .../kernel/syscalls/exit_group/exit_group01.c | 161 ++++++++++++------
 2 files changed, 112 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..0fb1b284c 100644
--- a/testcases/kernel/syscalls/exit_group/exit_group01.c
+++ b/testcases/kernel/syscalls/exit_group/exit_group01.c
@@ -1,68 +1,127 @@
-/******************************************************************************
- * 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 <sched.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include "tst_test.h"
 #include "lapi/syscalls.h"
+#include "tst_safe_pthread.h"
+
+static int cpu_count;
 
-char *TCID = "exit_group01";
-int testno;
-int TST_TOTAL = 1;
+static struct worker_data {
+	pid_t tid;
+	int counter;
+} *workers_data;
 
-static void verify_exit_group(void)
+static void *worker(void *arg)
 {
-	pid_t cpid, w;
-	int status;
+	struct worker_data *data;
 
-	cpid = fork();
-	if (cpid == -1)
-		tst_brkm(TFAIL | TERRNO, NULL, "fork failed");
+	data = (struct worker_data *)arg;
+	data->tid = tst_gettid();
 
-	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);
+	while (1) {
+		tst_atomic_inc(&data->counter);
+		sched_yield();
+	}
+
+	return arg;
+}
+
+static void spawn_threads(void)
+{
+	pthread_t threads[cpu_count];
+
+	for (int i = 0; i < cpu_count; i++)
+		SAFE_PTHREAD_CREATE(&threads[i], NULL, worker, (void *)(workers_data + i));
+}
+
+static void check_counters(void)
+{
+	struct worker_data data_copy[cpu_count];
+
+	memset(data_copy, 0, sizeof(struct worker_data) * cpu_count);
+	memcpy(data_copy, workers_data, sizeof(struct worker_data) * cpu_count);
+
+	tst_res(TINFO, "Checking if threads are still running");
+	usleep(100000);
+
+	struct worker_data *old_data;
+	struct worker_data *new_data;
+
+	for (int i = 0; i < cpu_count; i++) {
+		old_data = data_copy + i;
+		new_data = workers_data + i;
+
+		if (old_data->counter != new_data->counter) {
+			tst_res(TFAIL, "Counter value has changed for thread[%d]", i);
+			return;
 		}
 	}
+
+	tst_res(TINFO, "Threads counters value didn't change");
 }
 
-int main(int ac, char **av)
+static void run(void)
 {
-	int lc;
+	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;
+	}
 
-	tst_parse_opts(ac, av, NULL, NULL);
+	SAFE_WAITPID(pid, &status, 0);
 
-	for (lc = 0; TEST_LOOPING(lc); lc++)
-		verify_exit_group();
+	TST_EXP_EXPR(WIFEXITED(status) && WEXITSTATUS(status) == 4,
+		"exit_group() succeeded");
 
-	tst_exit();
+	check_counters();
 }
+
+static void setup(void)
+{
+	cpu_count = tst_ncpus();
+
+	workers_data = SAFE_MMAP(
+		NULL,
+		sizeof(struct worker_data) * cpu_count,
+		PROT_READ | PROT_WRITE,
+		MAP_SHARED | MAP_ANONYMOUS,
+		-1, 0);
+}
+
+static void cleanup(void)
+{
+	SAFE_MUNMAP(workers_data, sizeof(struct worker_data) * cpu_count);
+}
+
+static struct tst_test test = {
+	.setup = setup,
+	.cleanup = cleanup,
+	.test_all = run,
+	.forks_child = 1,
+	.needs_checkpoints = 1,
+};
-- 
2.35.3


-- 
Mailing list info: https://lists.linux.it/listinfo/ltp

Re: [LTP] [PATCH v5 0/2] Rewrite exit_group01 test

[Richard Palethorpe]

Hello,

Merged, thanks!

Andrea Cervesato <andrea.cervesato@suse.de> writes:

> From: Andrea Cervesato <andrea.cervesato@suse.com>
>
> exit_group01 test has been completely rewritten and tst_gettid() has been added
> to support missing gettid() syscall from GLIBC
>
> Andrea Cervesato (2):
>   Add tst_gettid wrapper around gettid syscall
>   Refactor exit_group01 using new API
>
>  include/tst_pid.h                             |   8 +
>  lib/tst_pid.c                                 |   5 +
>  testcases/kernel/syscalls/exit_group/Makefile |   2 +
>  .../kernel/syscalls/exit_group/exit_group01.c | 161 ++++++++++++------
>  4 files changed, 125 insertions(+), 51 deletions(-)
>
> -- 
> 2.35.3


-- 
Thank you,
Richard.

-- 
Mailing list info: https://lists.linux.it/listinfo/ltp