1ff636
From 4c6c21f92a8204abf031e42bb4949a0ecf039f7a Mon Sep 17 00:00:00 2001
1ff636
From: David Herrmann <dh.herrmann@gmail.com>
1ff636
Date: Wed, 11 Mar 2015 13:53:21 +0100
1ff636
Subject: [PATCH] bus-proxy: complain only once about queue overflows
1ff636
1ff636
If the local peer does not dispatch its incoming queue, the bus-proxy will
1ff636
slowly fill its outgoing queue. Once its full, it will continously
1ff636
complain that it cannot forward its messages.
1ff636
1ff636
As it turns out, pulseaudio does have an idle background dbus connection
1ff636
that is not integrated into any mainloop (and given that gdbus and
1ff636
libdbus1 both support background shared connections, PA is probably not
1ff636
the only example), therefore, the bus-proxy will loudly complain if it
1ff636
cannot forward NameOwnerChanged events once the queue is full.
1ff636
1ff636
This commit makes the proxy track queue-state and complain only once the
1ff636
queue runs full, not if it is already full.
1ff636
1ff636
A PA bug-report (and patch) has been filed, and other applications should
1ff636
be fixed similarly. Hence, lets keep the error message, instead of
1ff636
dropping it. It's unused resources we really want to get rid of, so
1ff636
silencing the message does not really help (which is actually what
1ff636
dbus-daemon does).
1ff636
1ff636
(cherry picked from commit ec2c7b56599981a7d9e76b15c75af3e1af3e6f81)
1ff636
---
1ff636
 src/bus-proxyd/proxy.c | 16 ++++++++++++----
1ff636
 src/bus-proxyd/proxy.h |  1 +
1ff636
 2 files changed, 13 insertions(+), 4 deletions(-)
1ff636
1ff636
diff --git a/src/bus-proxyd/proxy.c b/src/bus-proxyd/proxy.c
Pablo Greco 48fc63
index 3dea908f5b..e13cf5e2ea 100644
1ff636
--- a/src/bus-proxyd/proxy.c
1ff636
+++ b/src/bus-proxyd/proxy.c
1ff636
@@ -729,13 +729,21 @@ static int proxy_process_destination_to_local(Proxy *p) {
1ff636
 
1ff636
                 /* Return the error to the client, if we can */
1ff636
                 synthetic_reply_method_errnof(m, r, "Failed to forward message we got from destination: %m");
1ff636
-                log_error_errno(r,
1ff636
-                         "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",
1ff636
-                         p->local_creds.uid, p->local_creds.gid, bus_message_type_to_string(m->header->type),
1ff636
-                         strna(m->destination), strna(m->path), strna(m->interface), strna(m->member));
1ff636
+                if (r == -ENOBUFS) {
1ff636
+                        /* if local dbus1 peer does not dispatch its queue, warn only once */
1ff636
+                        if (!p->queue_overflow)
1ff636
+                                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);
1ff636
+                        p->queue_overflow = true;
1ff636
+                } else
1ff636
+                        log_error_errno(r,
1ff636
+                                 "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",
1ff636
+                                 p->local_creds.uid, p->local_creds.gid, bus_message_type_to_string(m->header->type),
1ff636
+                                 strna(m->destination), strna(m->path), strna(m->interface), strna(m->member));
1ff636
+
1ff636
                 return 1;
1ff636
         }
1ff636
 
1ff636
+        p->queue_overflow = false;
1ff636
         return 1;
1ff636
 }
1ff636
 
1ff636
diff --git a/src/bus-proxyd/proxy.h b/src/bus-proxyd/proxy.h
Pablo Greco 48fc63
index 913d47071b..782c4e60b3 100644
1ff636
--- a/src/bus-proxyd/proxy.h
1ff636
+++ b/src/bus-proxyd/proxy.h
1ff636
@@ -40,6 +40,7 @@ struct Proxy {
1ff636
         SharedPolicy *policy;
1ff636
 
1ff636
         bool got_hello : 1;
1ff636
+        bool queue_overflow : 1;
1ff636
 };
1ff636
 
1ff636
 int proxy_new(Proxy **out, int in_fd, int out_fd, const char *dest);