[PATCH 1/8] qio: Add trace points to net_listener

[Eric Blake <eblake@redhat.com>]

Upcoming patches will adjust how net_listener watches for new client
connections; adding trace points now makes it easier to debug that the
changes work as intended.  For example, adding
--trace='qio_net_listener*' to the qemu-storage-daemon command line
before --nbd-server will track when the server first starts listening
for clients.

Signed-off-by: Eric Blake <eblake@redhat.com>
---
 io/net-listener.c | 17 +++++++++++++++++
 io/trace-events   |  5 +++++
 2 files changed, 22 insertions(+)

diff --git a/io/net-listener.c b/io/net-listener.c
index 47405965a66..0adbc409cf2 100644
--- a/io/net-listener.c
+++ b/io/net-listener.c
@@ -23,6 +23,7 @@
 #include "io/dns-resolver.h"
 #include "qapi/error.h"
 #include "qemu/module.h"
+#include "trace.h"

 QIONetListener *qio_net_listener_new(void)
 {
@@ -50,6 +51,7 @@ static gboolean qio_net_listener_channel_func(QIOChannel *ioc,
         return TRUE;
     }

+    trace_qio_net_listener_callback(listener, listener->io_func);
     if (listener->io_func) {
         listener->io_func(listener, sioc, listener->io_data);
     }
@@ -124,6 +126,8 @@ void qio_net_listener_add(QIONetListener *listener,
     listener->connected = true;

     if (listener->io_func != NULL) {
+        trace_qio_net_listener_watch_enabled(listener, listener->io_func,
+                                             "add");
         object_ref(OBJECT(listener));
         listener->io_source[listener->nsioc] = qio_channel_add_watch_source(
             QIO_CHANNEL(listener->sioc[listener->nsioc]), G_IO_IN,
@@ -143,6 +147,9 @@ void qio_net_listener_set_client_func_full(QIONetListener *listener,
 {
     size_t i;

+    if (listener->io_func) {
+        trace_qio_net_listener_watch_disabled(listener, "set_client_func");
+    }
     if (listener->io_notify) {
         listener->io_notify(listener->io_data);
     }
@@ -159,6 +166,8 @@ void qio_net_listener_set_client_func_full(QIONetListener *listener,
     }

     if (listener->io_func != NULL) {
+        trace_qio_net_listener_watch_enabled(listener, listener->io_func,
+                                             "set_client_func");
         for (i = 0; i < listener->nsioc; i++) {
             object_ref(OBJECT(listener));
             listener->io_source[i] = qio_channel_add_watch_source(
@@ -218,6 +227,9 @@ QIOChannelSocket *qio_net_listener_wait_client(QIONetListener *listener)
     };
     size_t i;

+    if (listener->io_func) {
+        trace_qio_net_listener_watch_disabled(listener, "wait_client");
+    }
     for (i = 0; i < listener->nsioc; i++) {
         if (listener->io_source[i]) {
             g_source_destroy(listener->io_source[i]);
@@ -248,6 +260,8 @@ QIOChannelSocket *qio_net_listener_wait_client(QIONetListener *listener)
     g_main_context_unref(ctxt);

     if (listener->io_func != NULL) {
+        trace_qio_net_listener_watch_enabled(listener, listener->io_func,
+                                             "wait_client");
         for (i = 0; i < listener->nsioc; i++) {
             object_ref(OBJECT(listener));
             listener->io_source[i] = qio_channel_add_watch_source(
@@ -268,6 +282,9 @@ void qio_net_listener_disconnect(QIONetListener *listener)
         return;
     }

+    if (listener->io_func) {
+        trace_qio_net_listener_watch_disabled(listener, "disconnect");
+    }
     for (i = 0; i < listener->nsioc; i++) {
         if (listener->io_source[i]) {
             g_source_destroy(listener->io_source[i]);
diff --git a/io/trace-events b/io/trace-events
index dc3a63ba1fb..8cc4cae3a5d 100644
--- a/io/trace-events
+++ b/io/trace-events
@@ -72,3 +72,8 @@ qio_channel_command_new_pid(void *ioc, int writefd, int readfd, int pid) "Comman
 qio_channel_command_new_spawn(void *ioc, const char *binary, int flags) "Command new spawn ioc=%p binary=%s flags=%d"
 qio_channel_command_abort(void *ioc, int pid) "Command abort ioc=%p pid=%d"
 qio_channel_command_wait(void *ioc, int pid, int ret, int status) "Command abort ioc=%p pid=%d ret=%d status=%d"
+
+# net-listener.c
+qio_net_listener_watch_enabled(void *listener, void *func, const char *extra) "Net listener=%p watch enabled func=%p by %s"
+qio_net_listener_watch_disabled(void *listener, const char *extra) "Net listener=%p watch disabled by %s"
+qio_net_listener_callback(void *listener, void *func) "Net listener=%p callback forwarding to func=%p"
-- 
2.51.1