Merge pull request #32458 from poettering/manager_get_units_for_pidref

core: split out manager_get_units_for_pidref() and use it at multiple places
This commit is contained in:
Luca Boccassi
2024-04-24 21:28:52 +02:00
committed by GitHub
+82 -66
View File
@@ -2613,6 +2613,59 @@ static void manager_invoke_notify_message(
}
}
static int manager_get_units_for_pidref(Manager *m, const PidRef *pidref, Unit ***ret_units) {
/* Determine array of every unit that is interested in the specified process */
assert(m);
assert(pidref_is_set(pidref));
Unit *u1, *u2, **array;
u1 = manager_get_unit_by_pidref_cgroup(m, pidref);
u2 = hashmap_get(m->watch_pids, pidref);
array = hashmap_get(m->watch_pids_more, pidref);
size_t n = 0;
if (u1)
n++;
if (u2)
n++;
if (array)
for (size_t j = 0; array[j]; j++)
n++;
assert(n <= INT_MAX); /* Make sure we can reasonably return the counter as "int" */
if (ret_units) {
_cleanup_free_ Unit **units = NULL;
if (n > 0) {
units = new(Unit*, n + 1);
if (!units)
return -ENOMEM;
/* We return a dense array, and put the "main" unit first, i.e. unit in whose cgroup
* the process currently is. Note that we do not bother with filtering duplicates
* here. */
size_t i = 0;
if (u1)
units[i++] = u1;
if (u2)
units[i++] = u2;
if (array)
for (size_t j = 0; array[j]; j++)
units[i++] = array[j];
assert(i == n);
units[i] = NULL; /* end array in an extra NULL */
}
*ret_units = TAKE_PTR(units);
}
return (int) n;
}
static int manager_dispatch_notify_fd(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
Manager *m = ASSERT_PTR(userdata);
_cleanup_fdset_free_ FDSet *fds = NULL;
@@ -2632,12 +2685,9 @@ static int manager_dispatch_notify_fd(sd_event_source *source, int fd, uint32_t
struct cmsghdr *cmsg;
struct ucred *ucred = NULL;
_cleanup_free_ Unit **array_copy = NULL;
_cleanup_strv_free_ char **tags = NULL;
Unit *u1, *u2, **array;
int r, *fd_array = NULL;
size_t n_fds = 0;
bool found = false;
ssize_t n;
assert(m->notify_fd == fd);
@@ -2725,37 +2775,20 @@ static int manager_dispatch_notify_fd(sd_event_source *source, int fd, uint32_t
PidRef pidref = PIDREF_MAKE_FROM_PID(ucred->pid);
/* Notify every unit that might be interested, which might be multiple. */
u1 = manager_get_unit_by_pidref_cgroup(m, &pidref);
u2 = hashmap_get(m->watch_pids, &pidref);
array = hashmap_get(m->watch_pids_more, &pidref);
if (array) {
size_t k = 0;
_cleanup_free_ Unit **array = NULL;
while (array[k])
k++;
array_copy = newdup(Unit*, array, k+1);
if (!array_copy)
log_oom();
int n_array = manager_get_units_for_pidref(m, &pidref, &array);
if (n_array < 0) {
log_warning_errno(n_array, "Failed to determine units for PID " PID_FMT ", ignoring: %m", ucred->pid);
return 0;
}
/* And now invoke the per-unit callbacks. Note that manager_invoke_notify_message() will handle
* duplicate units make sure we only invoke each unit's handler once. */
if (u1) {
manager_invoke_notify_message(m, u1, ucred, tags, fds);
found = true;
}
if (u2) {
manager_invoke_notify_message(m, u2, ucred, tags, fds);
found = true;
}
if (array_copy)
for (size_t i = 0; array_copy[i]; i++) {
manager_invoke_notify_message(m, array_copy[i], ucred, tags, fds);
found = true;
}
if (!found)
log_warning("Cannot find unit for notify message of PID "PID_FMT", ignoring.", ucred->pid);
if (n_array == 0)
log_debug("Cannot find unit for notify message of PID "PID_FMT", ignoring.", ucred->pid);
else
/* And now invoke the per-unit callbacks. Note that manager_invoke_notify_message() will handle
* duplicate units – making sure we only invoke each unit's handler once. */
FOREACH_ARRAY(u, array, n_array)
manager_invoke_notify_message(m, *u, ucred, tags, fds);
if (!fdset_isempty(fds))
log_warning("Got extra auxiliary fds with notification message, closing them.");
@@ -2806,10 +2839,7 @@ static int manager_dispatch_sigchld(sd_event_source *source, void *userdata) {
goto turn_off;
if (IN_SET(si.si_code, CLD_EXITED, CLD_KILLED, CLD_DUMPED)) {
_cleanup_free_ Unit **array_copy = NULL;
_cleanup_free_ char *name = NULL;
Unit *u1, *u2, **array;
(void) pid_get_comm(si.si_pid, &name);
log_debug("Child "PID_FMT" (%s) died (code=%s, status=%i/%s)",
@@ -2827,41 +2857,27 @@ static int manager_dispatch_sigchld(sd_event_source *source, void *userdata) {
* pidfd here any more even if we wanted (since the process just exited). */
PidRef pidref = PIDREF_MAKE_FROM_PID(si.si_pid);
/* And now figure out the unit this belongs to, it might be multiple... */
u1 = manager_get_unit_by_pidref_cgroup(m, &pidref);
u2 = hashmap_get(m->watch_pids, &pidref);
array = hashmap_get(m->watch_pids_more, &pidref);
if (array) {
size_t n = 0;
/* Count how many entries the array has */
while (array[n])
n++;
/* Make a copy of the array so that we don't trip up on the array changing beneath us */
array_copy = newdup(Unit*, array, n+1);
if (!array_copy)
log_oom();
}
/* Finally, execute them all. Note that u1, u2 and the array might contain duplicates, but
* that's fine, manager_invoke_sigchld_event() will ensure we only invoke the handlers once for
* each iteration. */
if (u1) {
/* We check for oom condition, in case we got SIGCHLD before the oom notification.
* We only do this for the cgroup the PID belonged to. */
(void) unit_check_oom(u1);
/* And now figure out the units this belongs to, there might be multiple... */
_cleanup_free_ Unit **array = NULL;
int n_array = manager_get_units_for_pidref(m, &pidref, &array);
if (n_array < 0)
log_warning_errno(n_array, "Failed to get units for process " PID_FMT ", ignoring: %m", si.si_pid);
else if (n_array == 0)
log_debug("Got SIGCHLD for process " PID_FMT " we weren't interested in, ignoring.", si.si_pid);
else {
/* We check for an OOM condition, in case we got SIGCHLD before the OOM notification.
* We only do this for the cgroup the PID belonged to, which is the f */
(void) unit_check_oom(array[0]);
/* We check if systemd-oomd performed a kill so that we log and notify appropriately */
(void) unit_check_oomd_kill(u1);
(void) unit_check_oomd_kill(array[0]);
manager_invoke_sigchld_event(m, u1, &si);
/* Finally, execute them all. Note that the array might contain duplicates, but that's fine,
* manager_invoke_sigchld_event() will ensure we only invoke the handlers once for each
* iteration. */
FOREACH_ARRAY(u, array, n_array)
manager_invoke_sigchld_event(m, *u, &si);
}
if (u2)
manager_invoke_sigchld_event(m, u2, &si);
if (array_copy)
for (size_t i = 0; array_copy[i]; i++)
manager_invoke_sigchld_event(m, array_copy[i], &si);
}
/* And now, we actually reap the zombie. */