prefer query Screens::refreshRate()

ScreenInfo::rate is reporting 50Hz (on at least nvidia)
... AGAIN! * sigh*

In addition we check for __GL_SYNC_DISPLAY_DEVICE to pick
the rate of the screen that the driver will actually sync to
(hopefully...)

The patch is limited to nvidia systems for 5.3, applied everywhere
in master (ie. will be in 5.4 unless there's some problem)

BUG: 347360
REVIEW: 123693
This commit is contained in:
Thomas Lübking 2015-05-09 16:46:21 +02:00
parent 3597959c0e
commit 3158e987fa

View file

@ -29,6 +29,7 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
#include <QProcess>
#include "compositingprefs.h"
#include "screens.h"
#include "settings.h"
#include "xcbutils.h"
#include <kwinglplatform.h>
@ -43,21 +44,44 @@ namespace KWin
int currentRefreshRate()
{
int rate = -1;
if (options->refreshRate() > 0) // use manually configured refresh rate
QString syncScreenName(QLatin1String("primary screen"));
if (options->refreshRate() > 0) { // use manually configured refresh rate
rate = options->refreshRate();
else if (Xcb::Extensions::self()->isRandrAvailable()) {
} else if (GLPlatform::instance()->driver() == Driver_NVidia &&
Screens::self()->count() > 0) {
// prefer the refreshrate calculated from the screens mode information
// at least the nvidia driver reports 50Hz BS ... *again*!
int syncScreen = 0;
if (Screens::self()->count() > 1) {
const QByteArray syncDisplayDevice(qgetenv("__GL_SYNC_DISPLAY_DEVICE"));
// if __GL_SYNC_DISPLAY_DEVICE is exported, the GPU shall sync to that device
// so we try to use its refresh rate
if (!syncDisplayDevice.isEmpty()) {
for (int i = 0; i < Screens::self()->count(); ++i) {
if (Screens::self()->name(i) == syncDisplayDevice) {
syncScreenName = Screens::self()->name(i);
syncScreen = i;
break;
}
}
}
}
rate = qRound(Screens::self()->refreshRate(syncScreen)); // TODO forward float precision?
} else if (Xcb::Extensions::self()->isRandrAvailable()) {
// last restort - query XRandR screenInfo rate - probably wrong on nvidia systems
Xcb::RandR::ScreenInfo screenInfo(rootWindow());
rate = screenInfo->rate;
}
// 0Hz or less is invalid, so we fallback to a default rate
if (rate <= 0)
rate = 60;
rate = 60; // and not shitty 50Hz for sure! *grrr*
// QTimer gives us 1msec (1000Hz) at best, so we ignore anything higher;
// however, additional throttling prevents very high rates from taking place anyway
else if (rate > 1000)
rate = 1000;
qCDebug(KWIN_CORE) << "Vertical Refresh rate " << rate << "Hz";
qCDebug(KWIN_CORE) << "Vertical Refresh rate " << rate << "Hz (" << syncScreenName << ")";
return rate;
}