[Spice-devel] [vd-agent-win32 2/2] Use CCD API to update the WDDM display modes.

Frediano Ziglio fziglio at redhat.com
Thu Feb 11 12:04:09 CET 2016


> Hi, I answer inline

> El 10/02/16 a las 16:33, Frediano Ziglio escribió:

> > > When a new custom display mode is added, the current WDDM driver notifies
> > 
> 
> > > a disconnection and reconnection of the virtual monitor to force Windows
> > 
> 
> > > to update the display modes. This produces an ugly effect, keeping the
> > 
> 
> > > screen black for up to some seconds and usually not repainting it
> > 
> 
> > > afterwards.
> > 
> 

> > > This patch uses the CCD API to update the display modes, and produces
> > 
> 
> > > just a quick flash followed by a whole screen repaint. For best results,
> > 
> 
> > > it should be used with a driver that does not update the display modes
> > 
> 
> > > by itself, but it is still compatible with the current implementation.
> > 
> 
> > > ---
> > 
> 
> > > common/vdcommon.h          | 40 +++++++++++++++++++++++++++
> > 
> 
> > > vdagent/desktop_layout.cpp | 68
> > 
> 
> > > +++++++++++++++++++++++++++++++++++++++++++++-
> > 
> 
> > > 2 files changed, 107 insertions(+), 1 deletion(-)
> > 
> 

> > > diff --git a/common/vdcommon.h b/common/vdcommon.h
> > 
> 
> > > index f40e68e..29437c3 100644
> > 
> 
> > > --- a/common/vdcommon.h
> > 
> 
> > > +++ b/common/vdcommon.h
> > 
> 
> > > @@ -102,6 +102,46 @@ private:
> > 
> 
> > > PFND3DKMT_OPENADAPTERFROMHDC _pD3DKMTOpenAdapterFromHdc;
> > 
> 
> > > };
> > 
> 
> > > 
> > 
> 
> > > +// CCD API
> > 
> 
> > > +#define SDC_APPLY 0x00000080
> > 
> 
> > > +#define SDC_USE_SUPPLIED_DISPLAY_CONFIG 0x00000020
> > 
> 
> > > +#define SDC_FORCE_MODE_ENUMERATION 0x00001000
> > 
> 
> > > +#define QDC_ALL_PATHS 1
> > 
> 
> > > +struct DISPLAYCONFIG_PATH_INFO;
> > 
> 
> > > +struct DISPLAYCONFIG_MODE_INFO;
> > 
> 
> > > +struct DISPLAYCONFIG_TOPOLOGY_ID;
> > 
> 
> > > +typedef LONG (*PFNGETDISPLAYCONFIGBUFFERSIZES)(UINT32, UINT32*,
> > > UINT32*);
> > 
> 
> > > +typedef LONG (*PFNQUERYDISPLAYCONFIG)(UINT32, UINT32*,
> > 
> 
> > > DISPLAYCONFIG_PATH_INFO*, UINT32*,
> > 
> 
> > > +                                      DISPLAYCONFIG_MODE_INFO*,
> > 
> 
> > > DISPLAYCONFIG_TOPOLOGY_ID*);
> > 
> 
> > > +typedef LONG (*PFNSETDISPLAYCONFIG)(UINT32, DISPLAYCONFIG_PATH_INFO*,
> > 
> 
> > > UINT32,
> > 
> 
> > > +                                    DISPLAYCONFIG_MODE_INFO*, UINT32);
> > 
> 

So your system headers does not have definitions for these! 
My MingW have these definition in wingdi.h but you have to define WINVER >= 0x0601 before including the file. 
If your environment does not have such defines I would suggest to put these into a compat_ccd.h (for instance) file so 
is easy to remove in a future. 

> > > +class CCDLibrary {
> > 
> 
> > > +public:
> > 
> 
> > > +    ~CCDLibrary();
> > 
> 
> > > +    static CCDLibrary& singleton() {
> > 
> 
> > > +        static CCDLibrary instance;
> > 
> 
> > > +        return instance;
> > 
> 
> > > +    }
> > 
> 
> > > +    bool found() {
> > 
> 
> > > +        return _hUser32 && _pGetDisplayConfigBufferSizes &&
> > 
> 
> > > +               _pQuieryDisplayConfig && _pSetDisplayConfig;
> > 
> 
> > > +    }
> > 
> 

Why don't you return a CCDLibrary* from singleton returning NULL if you couldn't find the required APIs? 
This would avoid to expose a not initialized object and would remove the need for a found method. 

> > > +    LONG get_display_config_buffer_sizes(UINT32* num_paths, UINT32*
> > 
> 
> > > num_modes);
> > 
> 
> > > +    LONG query_display_config(UINT32* num_paths,
> > > DISPLAYCONFIG_PATH_INFO*
> > 
> 
> > > paths,
> > 
> 
> > > +                              UINT32* num_modes,
> > > DISPLAYCONFIG_MODE_INFO*
> > 
> 
> > > modes);
> > 
> 
> > > +    LONG set_display_config(UINT32 num_paths, DISPLAYCONFIG_PATH_INFO*
> > 
> 
> > > paths,
> > 
> 
> > > +                            UINT32 num_modes, DISPLAYCONFIG_MODE_INFO*
> > 
> 
> > > modes,
> > 
> 
> > > +                            UINT32 flags);
> > 
> 
> > > +
> > 
> 
> > > +private:
> > 
> 
> > > +    CCDLibrary();
> > 
> 

probably here you want also the copy constructor and assignment operator. 

> > > +
> > 
> 
> > > +    HINSTANCE _hUser32;
> > 
> 
> > > +    PFNGETDISPLAYCONFIGBUFFERSIZES _pGetDisplayConfigBufferSizes;
> > 
> 
> > > +    PFNQUERYDISPLAYCONFIG _pQuieryDisplayConfig;
> > 
> 
> > > +    PFNSETDISPLAYCONFIG _pSetDisplayConfig;
> > 
> 
> > > +};
> > 
> 
> > > +
> > 
> 
> > > #if defined __GNUC__
> > 
> 
> > > #define ALIGN_GCC __attribute__ ((packed))
> > 
> 
> > > #define ALIGN_VC
> > 
> 
> > > diff --git a/vdagent/desktop_layout.cpp b/vdagent/desktop_layout.cpp
> > 
> 
> > > index b5e8cfa..92493f3 100644
> > 
> 
> > > --- a/vdagent/desktop_layout.cpp
> > 
> 
> > > +++ b/vdagent/desktop_layout.cpp
> > 
> 
> > > @@ -312,6 +312,70 @@ NTSTATUS D3DKMTLibrary::close_adapter(D3DKMT_HANDLE
> > 
> 
> > > adapter)
> > 
> 
> > > return _pD3DKMTCloseAdapter(&func_params);
> > 
> 
> > > }
> > 
> 
> > > 
> > 
> 
> > > +CCDLibrary::CCDLibrary()
> > 
> 
> > > +    : _pGetDisplayConfigBufferSizes(NULL)
> > 
> 
> > > +    , _pQuieryDisplayConfig(NULL)
> > 
> 
> > > +    , _pSetDisplayConfig(NULL)
> > 
> 
> > > +{
> > 
> 
> > > +    _hUser32 = LoadLibrary(L"User32.dll");
> > 
> 

> > probably you want a GetModuleHandle, user32 have to be already available.
> 

> Ok, I'll send another patch

> > > +    if (_hUser32) {
> > 
> 
> > > +        _pGetDisplayConfigBufferSizes =
> > 
> 
> > > (PFNGETDISPLAYCONFIGBUFFERSIZES)GetProcAddress(_hUser32,
> > 
> 
> > > "GetDisplayConfigBufferSizes");
> > 
> 
> > > +        _pQuieryDisplayConfig =
> > 
> 
> > > (PFNQUERYDISPLAYCONFIG)GetProcAddress(_hUser32, "QueryDisplayConfig");
> > 
> 
> > > +        _pSetDisplayConfig =
> > > (PFNSETDISPLAYCONFIG)GetProcAddress(_hUser32,
> > 
> 
> > > "SetDisplayConfig");
> > 
> 
> > > +    }
> > 
> 
> > > +}
> > 
> 
> > > +
> > 
> 
> > > +
> > 
> 
> > > +CCDLibrary::~CCDLibrary()
> > 
> 
> > > +{
> > 
> 
> > > +    if (_hUser32)
> > 
> 
> > > +        FreeLibrary(_hUser32);
> > 
> 

> > If you use GetModuleHandle this is not necessary
> 

> > > +}
> > 
> 
> > > +
> > 
> 
> > > +LONG CCDLibrary::get_display_config_buffer_sizes(UINT32* num_paths,
> > > UINT32*
> > 
> 
> > > num_modes)
> > 
> 
> > > +{
> > 
> 
> > > +    return _pGetDisplayConfigBufferSizes(QDC_ALL_PATHS, num_paths,
> > 
> 
> > > num_modes);
> > 
> 
> > > +}
> > 
> 
> > > +
> > 
> 
> > > +LONG CCDLibrary::query_display_config(UINT32* num_paths,
> > 
> 
> > > DISPLAYCONFIG_PATH_INFO* paths,
> > 
> 
> > > +                                      UINT32* num_modes,
> > 
> 
> > > DISPLAYCONFIG_MODE_INFO* modes)
> > 
> 
> > > +{
> > 
> 
> > > +    return _pQuieryDisplayConfig(QDC_ALL_PATHS, num_paths, paths,
> > > num_modes,
> > 
> 
> > > modes, NULL);
> > 
> 
> > > +}
> > 
> 
> > > +
> > 
> 
> > > +LONG CCDLibrary::set_display_config(UINT32 num_paths,
> > 
> 
> > > DISPLAYCONFIG_PATH_INFO* paths,
> > 
> 
> > > +                                    UINT32 num_modes,
> > 
> 
> > > DISPLAYCONFIG_MODE_INFO* modes,
> > 
> 
> > > +                                    UINT32 flags)
> > 
> 
> > > +{
> > 
> 
> > > +    return _pSetDisplayConfig(num_paths, paths, num_modes, modes,
> > > flags);
> > 
> 
> > > +}
> > 
> 
> > > +
> > 
> 
> > > +static void update_display_modes()
> > 
> 
> > > +{
> > 
> 
> > > +    // The trick here is to call SetDisplayConfig with the current
> > > config
> > 
> 
> > > and
> > 
> 
> > > +    // the SDC_FORCE_MODE_ENUMERATION flag
> > 
> 
> > > +    CCDLibrary& ccd = CCDLibrary::singleton();
> > 
> 
> > > +    if (!ccd.found()) return;
> > 
> 
> > > +    UINT32 num_paths = 0, num_modes = 0;
> > 
> 
> > > +    DISPLAYCONFIG_PATH_INFO * paths;
> > 
> 
> > > +    DISPLAYCONFIG_MODE_INFO * modes;
> > 
> 
> > > +    LONG status = ccd.get_display_config_buffer_sizes(&num_paths,
> > 
> 
> > > &num_modes);
> > 
> 
> > > +    if (NT_SUCCESS(status)) {
> > 
> 
> > > +        // Being conservative, struct sizes are under 100 bytes
> > 
> 
> > > +        paths = reinterpret_cast<DISPLAYCONFIG_PATH_INFO *>(new
> > 
> 
> > > char[num_paths * 100]);
> > 
> 
> > > +        modes = reinterpret_cast<DISPLAYCONFIG_MODE_INFO *>(new
> > 
> 
> > > char[num_modes * 100]);
> > 
> 

> > why not
> 

> > paths = new DISPLAYCONFIG_PATH_INFO[num_paths];
> 
> > modes = new DISPLAYCONFIG_MODE_INFO[num_modes];
> 

once defined the types you could also use 

std::vector<DISPLAYCONFIG_PATH_INFO> paths(num_paths); 
std::vector<DISPLAYCONFIG_MODE_INFO> modes(num_modes); 

> This is to avoid having to fully define both DISPLAYCONFIG_PATH_INFO and
> DISPLAYCONFIG_MODE_INFO structs. The definition is quite long, and I am not
> using any of their members. Just filling two buffers with
> query_display_config and passing them to set_display_config. But if you
> think it is cleaner to include the full definition, I can do so in the next
> version of the patch.

> > > +        status = ccd.query_display_config(&num_paths, paths, &num_modes,
> > 
> 
> > > modes);
> > 
> 

Here you would use paths.front() 

> > > +        if (NT_SUCCESS(status)) {
> > 
> 
> > > +            ccd.set_display_config(num_paths, paths, num_modes, modes,
> > 
> 
> > > +                                   SDC_APPLY |
> > 
> 
> > > +                                   SDC_USE_SUPPLIED_DISPLAY_CONFIG |
> > 
> 
> > > +                                   SDC_FORCE_MODE_ENUMERATION);
> > 
> 
> > > +        }
> > 
> 
> > > +        delete[] reinterpret_cast<char *>(paths);
> > 
> 
> > > +        delete[] reinterpret_cast<char *>(modes);
> > 
> 

> > and here
> 

> > delete[] paths;
> 
> > delete[] modes;
> 

And here nothing! 

Frediano 

> Same here

> > Frediano
> 

> > > +    }
> > 
> 
> > > +}
> > 
> 
> > > +
> > 
> 
> > > bool DesktopLayout::init_dev_mode(LPCTSTR dev_name, DEVMODE* dev_mode,
> > 
> 
> > > DisplayMode* mode,
> > 
> 
> > > LONG normal_x, LONG normal_y, bool
> > 
> 
> > > set_pos)
> > 
> 
> > > {
> > 
> 
> > > @@ -384,7 +448,9 @@ bool DesktopLayout::init_dev_mode(LPCTSTR dev_name,
> > 
> 
> > > DEVMODE* dev_mode, DisplayMo
> > 
> 
> > > vd_printf("escape xres = %d, yres = %d, bpp = %d", custom.xres,
> > 
> 
> > > custom.yres, custom.bpp);
> > 
> 
> > > NTSTATUS status = d3dkmt.escape_driver_private(adapter, &custom,
> > 
> 
> > > sizeof(QXLEscapeSetCustomDisplay));
> > 
> 
> > > -            if (!NT_SUCCESS(status)) {
> > 
> 
> > > +            if (NT_SUCCESS(status)) {
> > 
> 
> > > +                update_display_modes();
> > 
> 
> > > +            } else {
> > 
> 
> > > vd_printf("escape failed with error 0x%08X", status);
> > 
> 
> > > }
> > 
> 
> > > }
> > 
> 

> --

> Javier Celaya

> Software Engineer

> j avier.celaya at flexvdi.com

> + 34 876 60 00 73

> @ j_celaya
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/spice-devel/attachments/20160211/fcc6ded9/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: logo.flexvdi.png
Type: image/png
Size: 17075 bytes
Desc: not available
URL: <https://lists.freedesktop.org/archives/spice-devel/attachments/20160211/fcc6ded9/attachment-0004.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: mail.png
Type: image/png
Size: 9350 bytes
Desc: not available
URL: <https://lists.freedesktop.org/archives/spice-devel/attachments/20160211/fcc6ded9/attachment-0005.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: phone.png
Type: image/png
Size: 15099 bytes
Desc: not available
URL: <https://lists.freedesktop.org/archives/spice-devel/attachments/20160211/fcc6ded9/attachment-0006.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: skype.png
Type: image/png
Size: 14444 bytes
Desc: not available
URL: <https://lists.freedesktop.org/archives/spice-devel/attachments/20160211/fcc6ded9/attachment-0007.png>


More information about the Spice-devel mailing list