Re: [PATCH] kselftests/sched: cleanup the child processes

On 9/1/21 10:43 PM, Li Zhijian wrote:

Previously, 'make -C sched run_tests' will block forever when it occurs something wrong where the *selftests framework* is waiting for its child processes to exit.

[root@iaas-rpma sched]# ./cs_prctl_test

## Create a thread/process/process group hiearchy Not a core sched system tid=74985, / tgid=74985 / pgid=74985: ffffffffffffffff Not a core sched system tid=74986, / tgid=74986 / pgid=74985: ffffffffffffffff Not a core sched system tid=74988, / tgid=74986 / pgid=74985: ffffffffffffffff Not a core sched system tid=74989, / tgid=74986 / pgid=74985: ffffffffffffffff Not a core sched system tid=74990, / tgid=74986 / pgid=74985: ffffffffffffffff Not a core sched system tid=74987, / tgid=74987 / pgid=74985: ffffffffffffffff Not a core sched system tid=74991, / tgid=74987 / pgid=74985: ffffffffffffffff Not a core sched system tid=74992, / tgid=74987 / pgid=74985: ffffffffffffffff Not a core sched system tid=74993, / tgid=74987 / pgid=74985: ffffffffffffffff

Not a core sched system (268) FAILED: get_cs_cookie(0) == 0

## Set a cookie on entire process group -1 = prctl(62, 1, 0, 2, 0) core_sched create failed -- PGID: Invalid argument (cs_prctl_test.c:272) - [root@iaas-rpma sched]# ps PID TTY TIME CMD 4605 pts/2 00:00:00 bash 74986 pts/2 00:00:00 cs_prctl_test 74987 pts/2 00:00:00 cs_prctl_test 74999 pts/2 00:00:00 ps

CC: Philip Li philip.li@intel.com Reported-by: kernel test robot lkp@intel.com Signed-off-by: Li Zhijian lizhijian@cn.fujitsu.com

---

tools/testing/selftests/sched/cs_prctl_test.c | 28 ++++++++++++------- 1 file changed, 18 insertions(+), 10 deletions(-)

diff --git a/tools/testing/selftests/sched/cs_prctl_test.c b/tools/testing/selftests/sched/cs_prctl_test.c index 63fe6521c56d..1829383715c6 100644 --- a/tools/testing/selftests/sched/cs_prctl_test.c +++ b/tools/testing/selftests/sched/cs_prctl_test.c @@ -64,6 +64,17 @@ enum pid_type {PIDTYPE_PID = 0, PIDTYPE_TGID, PIDTYPE_PGID}; const int THREAD_CLONE_FLAGS = CLONE_THREAD | CLONE_SIGHAND | CLONE_FS | CLONE_VM | CLONE_FILES; +struct child_args {

• int num_threads;
• int pfd[2];
• int cpid;
• int thr_tids[MAX_THREADS];

+};

+static struct child_args procs[MAX_PROCESSES]; +static int num_processes = 2; +static int need_cleanup = 0;

• static int _prctl(int option, unsigned long arg2, unsigned long arg3, unsigned long arg4, unsigned long arg5) {

@@ -80,8 +91,14 @@ static int _prctl(int option, unsigned long arg2, unsigned long arg3, unsigned l #define handle_error(msg) __handle_error(__FILE__, __LINE__, msg) static void __handle_error(char *fn, int ln, char *msg) {

• int pidx; printf("(%s:%d) - ", fn, ln); perror(msg);
• if (need_cleanup) {

• for (pidx = 0; pidx < num_processes; ++pidx)
  

• 	kill(procs[pidx].cpid, 15);
  

• need_cleanup = 0;
  

• } exit(EXIT_FAILURE); }

@@ -108,13 +125,6 @@ static unsigned long get_cs_cookie(int pid) return cookie; } -struct child_args {

• int num_threads;
• int pfd[2];
• int cpid;
• int thr_tids[MAX_THREADS];

-};

• static int child_func_thread(void __attribute__((unused))*arg) { while (1)

@@ -214,10 +224,7 @@ void _validate(int line, int val, char *msg) int main(int argc, char *argv[]) {

• struct child_args procs[MAX_PROCESSES];
• int keypress = 0;
• int num_processes = 2; int num_threads = 3; int delay = 0; int res = 0;

@@ -264,6 +271,7 @@ int main(int argc, char *argv[]) printf("\n## Create a thread/process/process group hiearchy\n"); create_processes(num_processes, num_threads, procs);

• need_cleanup = 1; disp_processes(num_processes, procs); validate(get_cs_cookie(0) == 0);

Reviewed-by: Chris Hyser chris.hyser@oracle.com