[systemd-commits] src/bus-proxyd

[David Herrmann]

 src/bus-proxyd/proxy.c |   16 ++++++++++++----
 src/bus-proxyd/proxy.h |    1 +
 2 files changed, 13 insertions(+), 4 deletions(-)

New commits:
commit ec2c7b56599981a7d9e76b15c75af3e1af3e6f81
Author: David Herrmann <dh.herrmann at gmail.com>
Date:   Wed Mar 11 13:53:21 2015 +0100

    bus-proxy: complain only once about queue overflows
    
    If the local peer does not dispatch its incoming queue, the bus-proxy will
    slowly fill its outgoing queue. Once its full, it will continously
    complain that it cannot forward its messages.
    
    As it turns out, pulseaudio does have an idle background dbus connection
    that is not integrated into any mainloop (and given that gdbus and
    libdbus1 both support background shared connections, PA is probably not
    the only example), therefore, the bus-proxy will loudly complain if it
    cannot forward NameOwnerChanged events once the queue is full.
    
    This commit makes the proxy track queue-state and complain only once the
    queue runs full, not if it is already full.
    
    A PA bug-report (and patch) has been filed, and other applications should
    be fixed similarly. Hence, lets keep the error message, instead of
    dropping it. It's unused resources we really want to get rid of, so
    silencing the message does not really help (which is actually what
    dbus-daemon does).

diff --git a/src/bus-proxyd/proxy.c b/src/bus-proxyd/proxy.c
index 0c851f9..c689618 100644
--- a/src/bus-proxyd/proxy.c
+++ b/src/bus-proxyd/proxy.c
@@ -719,13 +719,21 @@ static int proxy_process_destination_to_local(Proxy *p) {
 
                 /* Return the error to the client, if we can */
                 synthetic_reply_method_errnof(m, r, "Failed to forward message we got from destination: %m");
-                log_error_errno(r,
-                         "Failed to forward message we got from destination: uid=" UID_FMT " gid=" GID_FMT" message=%s destination=%s path=%s interface=%s member=%s: %m",
-                         p->local_creds.uid, p->local_creds.gid, bus_message_type_to_string(m->header->type),
-                         strna(m->destination), strna(m->path), strna(m->interface), strna(m->member));
+                if (r == -ENOBUFS) {
+                        /* if local dbus1 peer does not dispatch its queue, warn only once */
+                        if (!p->queue_overflow)
+                                log_error("Dropped messages due to queue overflow of local peer (pid: "PID_FMT" uid: "UID_FMT")", p->local_creds.pid, p->local_creds.uid);
+                        p->queue_overflow = true;
+                } else
+                        log_error_errno(r,
+                                 "Failed to forward message we got from destination: uid=" UID_FMT " gid=" GID_FMT" message=%s destination=%s path=%s interface=%s member=%s: %m",
+                                 p->local_creds.uid, p->local_creds.gid, bus_message_type_to_string(m->header->type),
+                                 strna(m->destination), strna(m->path), strna(m->interface), strna(m->member));
+
                 return 1;
         }
 
+        p->queue_overflow = false;
         return 1;
 }
 
diff --git a/src/bus-proxyd/proxy.h b/src/bus-proxyd/proxy.h
index 172bc7f..ff278a2 100644
--- a/src/bus-proxyd/proxy.h
+++ b/src/bus-proxyd/proxy.h
@@ -38,6 +38,7 @@ struct Proxy {
         SharedPolicy *policy;
 
         bool got_hello : 1;
+        bool queue_overflow : 1;
 };
 
 int proxy_new(Proxy **out, int in_fd, int out_fd, const char *dest);