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| author | Christian Brauner <brauner@kernel.org> | 2025-03-20 16:24:09 +0300 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2025-03-20 17:32:43 +0300 |
| commit | db7ce91e226df0fec200bd2a0eb87eed7c5d3adb (patch) | |
| tree | b8d183702d2fed5dfe1ec1cff9a28a3c42f47f20 /tools/testing/selftests/pidfd/pidfd_info_test.c | |
| parent | 0fb482728ba1ee2130eaa461bf551f014447997c (diff) | |
| download | linux-db7ce91e226df0fec200bd2a0eb87eed7c5d3adb.tar.xz | |
selftests/pidfd: first test for multi-threaded exec polling
Add first test for premature thread-group leader exit.
Link: https://lore.kernel.org/r/20250320-work-pidfs-thread_group-v4-2-da678ce805bf@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'tools/testing/selftests/pidfd/pidfd_info_test.c')
| -rw-r--r-- | tools/testing/selftests/pidfd/pidfd_info_test.c | 38 |
1 files changed, 31 insertions, 7 deletions
diff --git a/tools/testing/selftests/pidfd/pidfd_info_test.c b/tools/testing/selftests/pidfd/pidfd_info_test.c index 09bc4ae7aed5..28a28ae4686a 100644 --- a/tools/testing/selftests/pidfd/pidfd_info_test.c +++ b/tools/testing/selftests/pidfd/pidfd_info_test.c @@ -236,7 +236,7 @@ static void *pidfd_info_pause_thread(void *arg) TEST_F(pidfd_info, thread_group) { - pid_t pid_leader, pid_thread; + pid_t pid_leader, pid_poller, pid_thread; pthread_t thread; int nevents, pidfd_leader, pidfd_thread, pidfd_leader_thread, ret; int ipc_sockets[2]; @@ -262,6 +262,35 @@ TEST_F(pidfd_info, thread_group) syscall(__NR_exit, EXIT_SUCCESS); } + /* + * Opening a PIDFD_THREAD aka thread-specific pidfd based on a + * thread-group leader must succeed. + */ + pidfd_leader_thread = sys_pidfd_open(pid_leader, PIDFD_THREAD); + ASSERT_GE(pidfd_leader_thread, 0); + + pid_poller = fork(); + ASSERT_GE(pid_poller, 0); + if (pid_poller == 0) { + /* + * We can't poll and wait for the old thread-group + * leader to exit using a thread-specific pidfd. The + * thread-group leader exited prematurely and + * notification is delayed until all subthreads have + * exited. + */ + fds.events = POLLIN; + fds.fd = pidfd_leader_thread; + nevents = poll(&fds, 1, 10000 /* wait 5 seconds */); + if (nevents != 0) + _exit(EXIT_FAILURE); + if (fds.revents & POLLIN) + _exit(EXIT_FAILURE); + if (fds.revents & POLLHUP) + _exit(EXIT_FAILURE); + _exit(EXIT_SUCCESS); + } + /* Retrieve the tid of the thread. */ EXPECT_EQ(close(ipc_sockets[1]), 0); ASSERT_EQ(read_nointr(ipc_sockets[0], &pid_thread, sizeof(pid_thread)), sizeof(pid_thread)); @@ -275,12 +304,7 @@ TEST_F(pidfd_info, thread_group) pidfd_thread = sys_pidfd_open(pid_thread, PIDFD_THREAD); ASSERT_GE(pidfd_thread, 0); - /* - * Opening a PIDFD_THREAD aka thread-specific pidfd based on a - * thread-group leader must succeed. - */ - pidfd_leader_thread = sys_pidfd_open(pid_leader, PIDFD_THREAD); - ASSERT_GE(pidfd_leader_thread, 0); + ASSERT_EQ(wait_for_pid(pid_poller), 0); /* * Note that pidfd_leader is a thread-group pidfd, so polling on it |