[Spice-devel] [spice v1 1/2] display-channel: monitors_config: add 200ms delay

[Victor Toso]

From: Victor Toso <me at victortoso.com>

The device driver might take a few interactions to reconfigure all
displays but in each change it can send it down to spice-server. The
client is not interested in temporary states, only the final monitor
config can be helpful.

This patch adds a 200ms delay to wait for more changes from guest
device. Tested only with QXL in Fedora 29.

Simple example below, with 4 displays enabled but removing the display 1
(starting from 0), spice server receives:

 | 16:50:14.964: display-channel.c:173:monitors_config_unref: freeing monitors config
 | 16:50:14.964: display-channel.c:181:monitors_config_debug: monitors config count:3 max:4
 | 16:50:14.964: display-channel.c:185:monitors_config_debug: +0+0 960x997
 | 16:50:14.964: display-channel.c:185:monitors_config_debug: +960+0 1024x740
 | 16:50:14.964: display-channel.c:185:monitors_config_debug: +1984+0 1024x740

Sends to the client #1

 | 16:50:14.965: display-channel.c:173:monitors_config_unref: freeing monitors config
 | 16:50:14.965: display-channel.c:181:monitors_config_debug: monitors config count:3 max:4
 | 16:50:14.965: display-channel.c:185:monitors_config_debug: +0+0 960x997
 | 16:50:14.965: display-channel.c:185:monitors_config_debug: +0+0 0x0
 | 16:50:14.965: display-channel.c:185:monitors_config_debug: +1984+0 1024x740

Sends to the client #2

 | 16:50:14.966: red-worker.c:475:dev_create_primary_surface: trace
 | 16:50:14.967: display-channel.c:173:monitors_config_unref: freeing monitors config
 | 16:50:14.967: display-channel.c:181:monitors_config_debug: monitors config count:1 max:4
 | 16:50:14.967: display-channel.c:185:monitors_config_debug: +0+0 3008x997
 | 16:50:14.972: display-channel.c:173:monitors_config_unref: freeing monitors config
 | 16:50:14.972: display-channel.c:181:monitors_config_debug: monitors config count:3 max:4
 | 16:50:14.972: display-channel.c:185:monitors_config_debug: +0+0 960x997
 | 16:50:14.973: display-channel.c:185:monitors_config_debug: +0+0 0x0
 | 16:50:14.973: display-channel.c:185:monitors_config_debug: +960+0 1024x740

Sends to the client #3

 | 16:50:14.973: display-channel.c:2462:display_channel_update_monitors_config: Will update monitors in 200ms ~~
 | 16:50:14.975: display-channel.c:173:monitors_config_unref: freeing monitors config
 | 16:50:14.975: display-channel.c:181:monitors_config_debug: monitors config count:4 max:4
 | 16:50:14.975: display-channel.c:185:monitors_config_debug: +0+0 960x997
 | 16:50:14.975: display-channel.c:185:monitors_config_debug: +0+0 0x0
 | 16:50:14.975: display-channel.c:185:monitors_config_debug: +960+0 1024x740
 | 16:50:14.975: display-channel.c:185:monitors_config_debug: +1984+0 1024x740

Sends to the client #4 and final

With this patch, only the last one is sent.
Resolves: rhbz#1673072
Signed-off-by: Victor Toso <victortoso at redhat.com>
---
 server/display-channel-private.h |  2 ++
 server/display-channel.c         | 16 +++++++++++++---
 server/display-channel.h         |  2 +-
 3 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/server/display-channel-private.h b/server/display-channel-private.h
index 58179531..f1a4314c 100644
--- a/server/display-channel-private.h
+++ b/server/display-channel-private.h
@@ -118,6 +118,8 @@ struct DisplayChannelPrivate
 
     int gl_draw_async_count;
 
+    guint monitors_config_update_delay_id;
+
 /* TODO: some day unify this, make it more runtime.. */
     stat_info_t add_stat;
     stat_info_t exclude_stat;
diff --git a/server/display-channel.c b/server/display-channel.c
index e68ed10f..7e2584ec 100644
--- a/server/display-channel.c
+++ b/server/display-channel.c
@@ -2430,13 +2430,17 @@ gboolean display_channel_validate_surface(DisplayChannel *display, uint32_t surf
     return TRUE;
 }
 
-void display_channel_push_monitors_config(DisplayChannel *display)
+gboolean display_channel_push_monitors_config(gpointer userdata)
 {
     DisplayChannelClient *dcc;
+    DisplayChannel *display = userdata;
+
+    display->priv->monitors_config_update_delay_id = 0;
 
     FOREACH_DCC(display, dcc) {
         dcc_push_monitors_config(dcc);
     }
+    return G_SOURCE_REMOVE;
 }
 
 void display_channel_update_monitors_config(DisplayChannel *display,
@@ -2444,13 +2448,19 @@ void display_channel_update_monitors_config(DisplayChannel *display,
                                             uint16_t count, uint16_t max_allowed)
 {
 
-    if (display->priv->monitors_config)
+    if (display->priv->monitors_config) {
         monitors_config_unref(display->priv->monitors_config);
+    }
 
     display->priv->monitors_config =
         monitors_config_new(config->heads, count, max_allowed);
 
-    display_channel_push_monitors_config(display);
+    if (display->priv->monitors_config_update_delay_id != 0) {
+        g_source_remove(display->priv->monitors_config_update_delay_id);
+    }
+
+    display->priv->monitors_config_update_delay_id =
+        g_timeout_add (200, display_channel_push_monitors_config, display);
 }
 
 void display_channel_set_monitors_config_to_primary(DisplayChannel *display)
diff --git a/server/display-channel.h b/server/display-channel.h
index 948018cf..1d64afce 100644
--- a/server/display-channel.h
+++ b/server/display-channel.h
@@ -149,7 +149,7 @@ void                       display_channel_gl_draw_done              (DisplayCha
 void display_channel_update_monitors_config(DisplayChannel *display, QXLMonitorsConfig *config,
                                             uint16_t count, uint16_t max_allowed);
 void display_channel_set_monitors_config_to_primary(DisplayChannel *display);
-void display_channel_push_monitors_config(DisplayChannel *display);
+gboolean display_channel_push_monitors_config(gpointer display);
 
 gboolean display_channel_validate_surface(DisplayChannel *display, uint32_t surface_id);
 gboolean display_channel_surface_has_canvas(DisplayChannel *display, uint32_t surface_id);
-- 
2.20.1