From 541b25038a5de74411a094570b407c5ae018c2ba Mon Sep 17 00:00:00 2001 From: Maarten Maathuis Date: Sun, 30 Jan 2011 14:06:16 +0100 Subject: exa/mixed: Exclude frontbuffer from deferred pixmap handling. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit - Apps like xterm can trigger a lot of fallback rendering. - This can lead to (annoyingly) high latencies, because you have to wait for the block handler. - You need a driver that doesn't directly access the front buffer to trigger this (NV50+ nouveau for example). - Repeatingly doing dmesg on an xterm with a bitmap font will reveal that you never see part of the text. - I have recieved at least one complaint in the past of slow terminal performance, which was related to core font rendering. - This does sacrifice some throughput, roughly 33% slower. Reviewed-by: Michel Dänzer Signed-off-by: Maarten Maathuis Signed-off-by: Keith Packard --- exa/exa_migration_mixed.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) (limited to 'exa') diff --git a/exa/exa_migration_mixed.c b/exa/exa_migration_mixed.c index fb4715135..4f49905d3 100644 --- a/exa/exa_migration_mixed.c +++ b/exa/exa_migration_mixed.c @@ -138,6 +138,7 @@ void exaDamageReport_mixed(DamagePtr pDamage, RegionPtr pRegion, void *closure) { PixmapPtr pPixmap = closure; + ScreenPtr pScreen = pPixmap->drawable.pScreen; ExaPixmapPriv(pPixmap); /* Move back results of software rendering on system memory copy of mixed driver @@ -149,10 +150,18 @@ exaDamageReport_mixed(DamagePtr pDamage, RegionPtr pRegion, void *closure) if (!pExaPixmap->use_gpu_copy && exaPixmapHasGpuCopy(pPixmap)) { ExaScreenPriv(pPixmap->drawable.pScreen); - if (pExaScr->deferred_mixed_pixmap && - pExaScr->deferred_mixed_pixmap != pPixmap) - exaMoveInPixmap_mixed(pExaScr->deferred_mixed_pixmap); - pExaScr->deferred_mixed_pixmap = pPixmap; + /* Front buffer: Don't wait for the block handler to copy back the data. + * This avoids annoying latency if you encounter a lot of software rendering. + */ + if (pPixmap == pScreen->GetScreenPixmap(pScreen)) + exaMoveInPixmap_mixed(pPixmap); + else { + if (pExaScr->deferred_mixed_pixmap && + pExaScr->deferred_mixed_pixmap != pPixmap) + exaMoveInPixmap_mixed(pExaScr->deferred_mixed_pixmap); + + pExaScr->deferred_mixed_pixmap = pPixmap; + } } } -- cgit v1.2.3