git: 20917cac7bcf - main - sysv test: properly wait for children
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Date: Fri, 13 May 2022 21:40:09 UTC
The branch main has been updated by vangyzen:
URL: https://cgit.FreeBSD.org/src/commit/?id=20917cac7bcf216225a7b66f7b3a56f3764c5acc
commit 20917cac7bcf216225a7b66f7b3a56f3764c5acc
Author: Eric van Gyzen <vangyzen@FreeBSD.org>
AuthorDate: 2022-05-12 14:50:02 +0000
Commit: Eric van Gyzen <vangyzen@FreeBSD.org>
CommitDate: 2022-05-13 16:38:26 +0000
sysv test: properly wait for children
In the msg and shm tests, if the child exited before the parent
entered sigsuspend(), the test would hang and time out. This was
also a problem in the sem test, but the misuse of atf_tc_pass()
masked it. Adding a short sleep before the sigsuspend() calls made
the hang 100% reliable. With the same sleep in the new version,
the test passes reliably.
Remove calls to atf_tc_pass(). The call in the sem test broke the test
by exiting prematurely, after only one child out of five had finished.
The other two were harmless but unhelpful.
Reduce a one-second sleep to a more reasonable duration so I can quickly
run many iterations of the test.
Where feasible, assert that wait() returns the child PID. While I'm here,
use the more succinct ATF_REQUIRE* instead of if/atf_tc_fail/else.
Flush stdout before forking to avoid double-flush.
Use errx() when errno is irrelevant.
Don't use ATF_REQUIRE* in children. Apparently, the output doesn't
get saved. The exit status works, so it fails correctly, but silently.
Re-enable the test in CI.
PR: 233649
Reviewed by: markj (previous version)
MFC after: 1 week
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D35187
---
contrib/netbsd-tests/kernel/t_sysv.c | 201 ++++++++++-------------------------
1 file changed, 59 insertions(+), 142 deletions(-)
diff --git a/contrib/netbsd-tests/kernel/t_sysv.c b/contrib/netbsd-tests/kernel/t_sysv.c
index c28e72bfc212..847c9d83824d 100644
--- a/contrib/netbsd-tests/kernel/t_sysv.c
+++ b/contrib/netbsd-tests/kernel/t_sysv.c
@@ -54,11 +54,9 @@
#include <sys/shm.h>
#include <sys/wait.h>
-volatile int did_sigsys, did_sigchild;
-volatile int child_status, child_count;
+volatile int did_sigsys;
void sigsys_handler(int);
-void sigchld_handler(int);
key_t get_ftok(int);
@@ -142,23 +140,6 @@ sigsys_handler(int signo)
did_sigsys = 1;
}
-void
-sigchld_handler(int signo)
-{
- int c_status;
-
- did_sigchild = 1;
- /*
- * Reap the child and return its status
- */
- if (wait(&c_status) == -1)
- child_status = -errno;
- else
- child_status = c_status;
-
- child_count--;
-}
-
key_t get_ftok(int id)
{
int fd;
@@ -205,13 +186,10 @@ ATF_TC_BODY(msg, tc)
struct sigaction sa;
struct msqid_ds m_ds;
struct testmsg m;
- sigset_t sigmask;
int sender_msqid;
int loop;
int c_status;
-
- if (atf_tc_get_config_var_as_bool_wd(tc, "ci", false))
- atf_tc_skip("https://bugs.freebsd.org/233649");
+ pid_t wait_result;
/*
* Install a SIGSYS handler so that we can exit gracefully if
@@ -224,18 +202,6 @@ ATF_TC_BODY(msg, tc)
ATF_REQUIRE_MSG(sigaction(SIGSYS, &sa, NULL) != -1,
"sigaction SIGSYS: %d", errno);
- /*
- * Install a SIGCHLD handler to deal with all possible exit
- * conditions of the receiver.
- */
- did_sigchild = 0;
- child_count = 0;
- sa.sa_handler = sigchld_handler;
- sigemptyset(&sa.sa_mask);
- sa.sa_flags = 0;
- ATF_REQUIRE_MSG(sigaction(SIGCHLD, &sa, NULL) != -1,
- "sigaction SIGCHLD: %d", errno);
-
msgkey = get_ftok(4160);
ATF_REQUIRE_MSG(msgkey != (key_t)-1, "get_ftok failed");
@@ -268,13 +234,14 @@ ATF_TC_BODY(msg, tc)
print_msqid_ds(&m_ds, 0600);
+ fflush(stdout);
+
switch ((child_pid = fork())) {
case -1:
atf_tc_fail("fork: %d", errno);
return;
case 0:
- child_count++;
receiver();
break;
@@ -313,29 +280,18 @@ ATF_TC_BODY(msg, tc)
/*
* Wait for child to finish
*/
- sigemptyset(&sigmask);
- (void) sigsuspend(&sigmask);
+ wait_result = wait(&c_status);
+ ATF_REQUIRE_EQ_MSG(wait_result, child_pid, "wait returned %d (%s)",
+ wait_result, wait_result == -1 ? strerror(errno) : "");
+ ATF_REQUIRE_MSG(WIFEXITED(c_status), "child abnormal exit: %d (sig %d)",
+ c_status, WTERMSIG(c_status));
+ ATF_REQUIRE_EQ_MSG(WEXITSTATUS(c_status), 0, "child status: %d",
+ WEXITSTATUS(c_status));
- /*
- * ...and any other signal is an unexpected error.
- */
- if (did_sigchild) {
- c_status = child_status;
- if (c_status < 0)
- atf_tc_fail("waitpid: %d", -c_status);
- else if (WIFEXITED(c_status) == 0)
- atf_tc_fail("child abnormal exit: %d", c_status);
- else if (WEXITSTATUS(c_status) != 0)
- atf_tc_fail("c status: %d", WEXITSTATUS(c_status));
- else {
- ATF_REQUIRE_MSG(msgctl(sender_msqid, IPC_STAT, &m_ds)
- != -1, "msgctl IPC_STAT: %d", errno);
-
- print_msqid_ds(&m_ds, 0600);
- atf_tc_pass();
- }
- } else
- atf_tc_fail("sender: received unexpected signal");
+ ATF_REQUIRE_MSG(msgctl(sender_msqid, IPC_STAT, &m_ds) != -1,
+ "msgctl IPC_STAT: %d", errno);
+
+ print_msqid_ds(&m_ds, 0600);
}
ATF_TC_CLEANUP(msg, tc)
@@ -401,7 +357,7 @@ receiver(void)
printf("%s\n", m.mtext);
if (strcmp(m.mtext, m1_str) != 0)
- err(1, "receiver: message 1 data isn't correct");
+ errx(1, "receiver: message 1 data isn't correct");
m.mtype = MTYPE_1_ACK;
@@ -417,7 +373,7 @@ receiver(void)
printf("%s\n", m.mtext);
if (strcmp(m.mtext, m2_str) != 0)
- err(1, "receiver: message 2 data isn't correct");
+ errx(1, "receiver: message 2 data isn't correct");
m.mtype = MTYPE_2_ACK;
@@ -445,10 +401,11 @@ ATF_TC_BODY(sem, tc)
struct sigaction sa;
union semun sun;
struct semid_ds s_ds;
- sigset_t sigmask;
int sender_semid;
int i;
int c_status;
+ int child_count;
+ pid_t wait_result;
/*
* Install a SIGSYS handler so that we can exit gracefully if
@@ -461,18 +418,6 @@ ATF_TC_BODY(sem, tc)
ATF_REQUIRE_MSG(sigaction(SIGSYS, &sa, NULL) != -1,
"sigaction SIGSYS: %d", errno);
- /*
- * Install a SIGCHLD handler to deal with all possible exit
- * conditions of the receiver.
- */
- did_sigchild = 0;
- child_count = 0;
- sa.sa_handler = sigchld_handler;
- sigemptyset(&sa.sa_mask);
- sa.sa_flags = 0;
- ATF_REQUIRE_MSG(sigaction(SIGCHLD, &sa, NULL) != -1,
- "sigaction SIGCHLD: %d", errno);
-
semkey = get_ftok(4160);
ATF_REQUIRE_MSG(semkey != (key_t)-1, "get_ftok failed");
@@ -508,6 +453,8 @@ ATF_TC_BODY(sem, tc)
print_semid_ds(&s_ds, 0600);
+ fflush(stdout);
+
for (child_count = 0; child_count < 5; child_count++) {
switch ((child_pid = fork())) {
case -1:
@@ -546,34 +493,21 @@ ATF_TC_BODY(sem, tc)
/*
* Wait for all children to finish
*/
- sigemptyset(&sigmask);
- for (;;) {
- (void) sigsuspend(&sigmask);
- if (did_sigchild) {
- c_status = child_status;
- if (c_status < 0)
- atf_tc_fail("waitpid: %d", -c_status);
- else if (WIFEXITED(c_status) == 0)
- atf_tc_fail("c abnormal exit: %d", c_status);
- else if (WEXITSTATUS(c_status) != 0)
- atf_tc_fail("c status: %d",
- WEXITSTATUS(c_status));
- else {
- sun.buf = &s_ds;
- ATF_REQUIRE_MSG(semctl(sender_semid, 0,
- IPC_STAT, sun) != -1,
- "semctl IPC_STAT: %d", errno);
-
- print_semid_ds(&s_ds, 0600);
- atf_tc_pass();
- }
- if (child_count <= 0)
- break;
- did_sigchild = 0;
- } else {
- atf_tc_fail("sender: received unexpected signal");
- break;
- }
+ while (child_count-- > 0) {
+ wait_result = wait(&c_status);
+ ATF_REQUIRE_MSG(wait_result != -1, "wait failed: %s",
+ strerror(errno));
+ ATF_REQUIRE_MSG(WIFEXITED(c_status),
+ "child abnormal exit: %d (sig %d)",
+ c_status, WTERMSIG(c_status));
+ ATF_REQUIRE_EQ_MSG(WEXITSTATUS(c_status), 0, "child status: %d",
+ WEXITSTATUS(c_status));
+
+ sun.buf = &s_ds;
+ ATF_REQUIRE_MSG(semctl(sender_semid, 0, IPC_STAT, sun) != -1,
+ "semctl IPC_STAT: %d", errno);
+
+ print_semid_ds(&s_ds, 0600);
}
}
@@ -640,7 +574,7 @@ waiter(void)
err(1, "waiter: semop -1");
printf("WOO! GOT THE SEMAPHORE!\n");
- sleep(1);
+ usleep(10000);
/*
* Release the semaphore and exit.
@@ -671,10 +605,10 @@ ATF_TC_BODY(shm, tc)
{
struct sigaction sa;
struct shmid_ds s_ds;
- sigset_t sigmask;
char *shm_buf;
int sender_shmid;
int c_status;
+ pid_t wait_result;
/*
* Install a SIGSYS handler so that we can exit gracefully if
@@ -687,18 +621,6 @@ ATF_TC_BODY(shm, tc)
ATF_REQUIRE_MSG(sigaction(SIGSYS, &sa, NULL) != -1,
"sigaction SIGSYS: %d", errno);
- /*
- * Install a SIGCHLD handler to deal with all possible exit
- * conditions of the sharer.
- */
- did_sigchild = 0;
- child_count = 0;
- sa.sa_handler = sigchld_handler;
- sigemptyset(&sa.sa_mask);
- sa.sa_flags = 0;
- ATF_REQUIRE_MSG(sigaction(SIGCHLD, &sa, NULL) != -1,
- "sigaction SIGCHLD: %d", errno);
-
pgsize = sysconf(_SC_PAGESIZE);
shmkey = get_ftok(4160);
@@ -737,6 +659,8 @@ ATF_TC_BODY(shm, tc)
*/
strcpy(shm_buf, m2_str);
+ fflush(stdout);
+
switch ((child_pid = fork())) {
case -1:
atf_tc_fail("fork: %d", errno);
@@ -753,27 +677,18 @@ ATF_TC_BODY(shm, tc)
/*
* Wait for child to finish
*/
- sigemptyset(&sigmask);
- (void) sigsuspend(&sigmask);
-
- if (did_sigchild) {
- c_status = child_status;
- if (c_status < 0)
- atf_tc_fail("waitpid: %d", -c_status);
- else if (WIFEXITED(c_status) == 0)
- atf_tc_fail("c abnormal exit: %d", c_status);
- else if (WEXITSTATUS(c_status) != 0)
- atf_tc_fail("c status: %d", WEXITSTATUS(c_status));
- else {
- ATF_REQUIRE_MSG(shmctl(sender_shmid, IPC_STAT,
- &s_ds) != -1,
- "shmctl IPC_STAT: %d", errno);
-
- print_shmid_ds(&s_ds, 0600);
- atf_tc_pass();
- }
- } else
- atf_tc_fail("sender: received unexpected signal");
+ wait_result = wait(&c_status);
+ ATF_REQUIRE_EQ_MSG(wait_result, child_pid, "wait returned %d (%s)",
+ wait_result, wait_result == -1 ? strerror(errno) : "");
+ ATF_REQUIRE_MSG(WIFEXITED(c_status), "child abnormal exit: %d (sig %d)",
+ c_status, WTERMSIG(c_status));
+ ATF_REQUIRE_EQ_MSG(WEXITSTATUS(c_status), 0, "child status: %d",
+ WEXITSTATUS(c_status));
+
+ ATF_REQUIRE_MSG(shmctl(sender_shmid, IPC_STAT, &s_ds) != -1,
+ "shmctl IPC_STAT: %d", errno);
+
+ print_shmid_ds(&s_ds, 0600);
}
static void
@@ -836,15 +751,17 @@ sharer(void)
void *shm_buf;
shmid = shmget(shmkey, pgsize, 0);
- ATF_REQUIRE_MSG(shmid != -1, "receiver: shmget:%d", errno);
+ if (shmid == -1)
+ err(1, "receiver: shmget");
shm_buf = shmat(shmid, NULL, 0);
- ATF_REQUIRE_MSG(shm_buf != (void *) -1, "receiver: shmat: %d", errno);
+ if (shm_buf == (void *) -1)
+ err(1, "receiver: shmat");
printf("%s\n", (const char *)shm_buf);
-
- ATF_REQUIRE_MSG(strcmp((const char *)shm_buf, m2_str) == 0,
- "receiver: data isn't correct");
+
+ if (strcmp((const char *)shm_buf, m2_str) != 0)
+ errx(1, "receiver: data isn't correct");
exit(0);
}