service: make main pid guessing optional, and reread pid file after reloads

1 files changed, 16 insertions, 6 deletions

diff --git a/src/service.c b/src/service.c
index 60576dfed7..243e5536a7 100644
--- a/src/service.c
+++ b/src/service.c
@@ -118,6 +118,7 @@ static void service_init(Unit *u) {
         s->sysv_start_priority = -1;
 #endif
         s->socket_fd = -1;
+        s->guess_main_pid = true;
 
         exec_context_init(&s->exec_context);
 
@@ -1151,6 +1152,7 @@ static void service_dump(Unit *u, FILE *f, const char *prefix) {
                 "%sPermissionsStartOnly: %s\n"
                 "%sRootDirectoryStartOnly: %s\n"
                 "%sRemainAfterExit: %s\n"
+                "%sGuessMainPID: %s\n"
                 "%sType: %s\n"
                 "%sRestart: %s\n"
                 "%sNotifyAccess: %s\n",
@@ -1158,6 +1160,7 @@ static void service_dump(Unit *u, FILE *f, const char *prefix) {
                 prefix, yes_no(s->permissions_start_only),
                 prefix, yes_no(s->root_directory_start_only),
                 prefix, yes_no(s->remain_after_exit),
+                prefix, yes_no(s->guess_main_pid),
                 prefix, service_type_to_string(s->type),
                 prefix, service_restart_to_string(s->restart),
                 prefix, notify_access_to_string(s->notify_access));
@@ -1236,11 +1239,6 @@ static int service_load_pid_file(Service *s) {
 
         assert(s);
 
-        if (s->main_pid_known)
-                return 0;
-
-        assert(s->main_pid <= 0);
-
         if (!s->pid_file)
                 return -ENOENT;
 
@@ -1275,9 +1273,14 @@ static int service_search_main_pid(Service *s) {
 
         assert(s);
 
+        /* If we know it anyway, don't ever fallback to unreliable
+         * heuristics */
         if (s->main_pid_known)
                 return 0;
 
+        if (!s->guess_main_pid)
+                return 0;
+
         assert(s->main_pid <= 0);
 
         if ((pid = cgroup_bonding_search_main_pid_list(s->meta.cgroup_bondings)) <= 0)
@@ -2674,9 +2677,16 @@ static void service_sigchld_event(Unit *u, pid_t pid, int code, int status) {
                                                 log_warning("%s: failed to load PID file %s: %s", s->meta.id, s->pid_file, strerror(-r));
                                 }
 
-                                /* Fall through */
+                                s->reload_failure = !success;
+                                service_enter_running(s, true);
+                                break;
 
                         case SERVICE_RELOAD:
+                                if (success) {
+                                        service_load_pid_file(s);
+                                        service_search_main_pid(s);
+                                }
+
                                 s->reload_failure = !success;
                                 service_enter_running(s, true);
                                 break;