From c233fdd40580baf460b34655aa72a9a489b4501b Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Thu, 7 Mar 2019 09:11:50 +0000 Subject: [PATCH 5/9] vnc: detect and optimize pageflips MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RH-Author: Gerd Hoffmann Message-id: <20190307091150.6551-2-kraxel@redhat.com> Patchwork-id: 84816 O-Subject: [RHEL-8.0/AV qemu-kvm PATCH 1/1] vnc: detect and optimize pageflips Bugzilla: 1666206 RH-Acked-by: Philippe Mathieu-Daudé RH-Acked-by: Stefan Hajnoczi RH-Acked-by: John Snow When size and format of the display surface stays the same we can just tag the guest display as dirty and be done with it. There is no need need to resize the vnc server display or to touch the vnc client dirty bits. On the next refresh cycle vnc_refresh_server_surface() will check for actual display content changes and update the client dirty bits as needed. The desktop resize and framebuffer format notifications to the vnc client will be skipped too. Signed-off-by: Gerd Hoffmann Reviewed-by: Daniel P. Berrangé Message-id: 20190116101049.8929-1-kraxel@redhat.com (cherry picked from commit 61e77a5f0c788495566aecb437bcf6b2cf9cda97) Signed-off-by: Danilo C. L. de Paula --- ui/vnc.c | 25 ++++++++++++++++++++++--- 1 file changed, 22 insertions(+), 3 deletions(-) diff --git a/ui/vnc.c b/ui/vnc.c index d7903a7..765bdc5 100644 --- a/ui/vnc.c +++ b/ui/vnc.c @@ -742,6 +742,17 @@ static void vnc_update_server_surface(VncDisplay *vd) width, height); } +static bool vnc_check_pageflip(DisplaySurface *s1, + DisplaySurface *s2) +{ + return (s1 != NULL && + s2 != NULL && + surface_width(s1) == surface_width(s2) && + surface_height(s1) == surface_height(s2) && + surface_format(s1) == surface_format(s2)); + +} + static void vnc_dpy_switch(DisplayChangeListener *dcl, DisplaySurface *surface) { @@ -749,6 +760,7 @@ static void vnc_dpy_switch(DisplayChangeListener *dcl, "Display output is not active."; static DisplaySurface *placeholder; VncDisplay *vd = container_of(dcl, VncDisplay, dcl); + bool pageflip = vnc_check_pageflip(vd->ds, surface); VncState *vs; if (surface == NULL) { @@ -761,14 +773,21 @@ static void vnc_dpy_switch(DisplayChangeListener *dcl, vnc_abort_display_jobs(vd); vd->ds = surface; - /* server surface */ - vnc_update_server_surface(vd); - /* guest surface */ qemu_pixman_image_unref(vd->guest.fb); vd->guest.fb = pixman_image_ref(surface->image); vd->guest.format = surface->format; + if (pageflip) { + vnc_set_area_dirty(vd->guest.dirty, vd, 0, 0, + surface_width(surface), + surface_height(surface)); + return; + } + + /* server surface */ + vnc_update_server_surface(vd); + QTAILQ_FOREACH(vs, &vd->clients, next) { vnc_colordepth(vs); vnc_desktop_resize(vs); -- 1.8.3.1