console: add graphic_hw_update_done()

Add a function to be called when a graphic update is done.

Declare the QXL renderer as async: render_update_cookie_num counts the
number of outstanding updates, and graphic_hw_update_done() is called
when it reaches none.

(note: this is preliminary work for asynchronous screendump support)

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>

hw/display/qxl-render.c

@@ -109,7 +109,7 @@ static void qxl_render_update_area_unlocked(PCIQXLDevice *qxl)
                                                 qxl->guest_primary.surface.mem,
                                                 MEMSLOT_GROUP_GUEST);
         if (!qxl->guest_primary.data) {
-            return;
+            goto end;
         }
         qxl_set_rect_to_surface(qxl, &qxl->dirty[0]);
         qxl->num_dirty_rects = 1;
@@ -137,7 +137,7 @@ static void qxl_render_update_area_unlocked(PCIQXLDevice *qxl)
     }
 
     if (!qxl->guest_primary.data) {
-        return;
+        goto end;
     }
     for (i = 0; i < qxl->num_dirty_rects; i++) {
         if (qemu_spice_rect_is_empty(qxl->dirty+i)) {
@@ -158,6 +158,11 @@ static void qxl_render_update_area_unlocked(PCIQXLDevice *qxl)
                        qxl->dirty[i].bottom - qxl->dirty[i].top);
     }
     qxl->num_dirty_rects = 0;
+
+end:
+    if (qxl->render_update_cookie_num == 0) {
+        graphic_hw_update_done(qxl->ssd.dcl.con);
+    }
 }
 
 /*

hw/display/qxl.c

@@ -1181,6 +1181,7 @@ static const QXLInterface qxl_interface = {
 
 static const GraphicHwOps qxl_ops = {
     .gfx_update  = qxl_hw_update,
+    .gfx_update_async = true,
 };
 
 static void qxl_enter_vga_mode(PCIQXLDevice *d)

include/ui/console.h

@@ -365,6 +365,7 @@ static inline void console_write_ch(console_ch_t *dest, uint32_t ch)
 typedef struct GraphicHwOps {
     void (*invalidate)(void *opaque);
     void (*gfx_update)(void *opaque);
+    bool gfx_update_async; /* if true, calls graphic_hw_update_done() */
     void (*text_update)(void *opaque, console_ch_t *text);
     void (*update_interval)(void *opaque, uint64_t interval);
     int (*ui_info)(void *opaque, uint32_t head, QemuUIInfo *info);
@@ -380,6 +381,7 @@ void graphic_console_set_hwops(QemuConsole *con,
 void graphic_console_close(QemuConsole *con);
 
 void graphic_hw_update(QemuConsole *con);
+void graphic_hw_update_done(QemuConsole *con);
 void graphic_hw_invalidate(QemuConsole *con);
 void graphic_hw_text_update(QemuConsole *con, console_ch_t *chardata);
 void graphic_hw_gl_block(QemuConsole *con, bool block);

ui/console.c

@@ -259,13 +259,22 @@ static void gui_setup_refresh(DisplayState *ds)
     ds->have_text = have_text;
 }
 
+void graphic_hw_update_done(QemuConsole *con)
+{
+}
+
 void graphic_hw_update(QemuConsole *con)
 {
+    bool async = false;
     if (!con) {
         con = active_console;
     }
     if (con && con->hw_ops->gfx_update) {
         con->hw_ops->gfx_update(con->hw);
+        async = con->hw_ops->gfx_update_async;
+    }
+    if (!async) {
+        graphic_hw_update_done(con);
     }
 }