sd-event: improve debug message when we fail to remove and fd from an epoll

Let's help users to debug issues with epoll fd removal by printing the
name of the event source.

diff --git a/src/libsystemd/sd-event/sd-event.c b/src/libsystemd/sd-event/sd-event.c
index 0e33ced342bf4040de3e56898465cf0266665617..c419be820afcf3854f2e36ca702589fd7857098d 100644 (file)
--- a/src/libsystemd/sd-event/sd-event.c
+++ b/src/libsystemd/sd-event/sd-event.c
@@ -481,7 +481,8 @@ static void source_io_unregister(sd_event_source *s) {
                 return;
 
         r = epoll_ctl(s->event->epoll_fd, EPOLL_CTL_DEL, s->io.fd, NULL);
-        assert_log(r >= 0);
+        if (r < 0)
+                log_debug_errno(errno, "Failed to remove source %s from epoll: %m", strna(s->description));
 
         s->io.registered = false;
 }