From 2eec53d0b9232970fe3d03ce6c8940ebeea44bee Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 23 Mar 2010 17:28:22 +0000 Subject: [PATCH] uxa: Default to using TILING_X for pixmaps. On memory constrained hardware, tiling is vital for good performance as it minimizes cache misses. The downside is that for older hardware (which often suffers from the lack of bandwidth) requires the use of fences for many operations, which are in short supply and so may cause shorter batchbuffers. However our batch buffers are typically short and so this is unlikely to be a concern and not affect the performance wins. A quick bit of testing suggests the effect is inconclusive on firefox/i945: linear tiled xcb 205.470 206.219 xcb-render-0.0 404.704 388.413 xlib 166.410 170.805 A secondary effect of the patch is to workaround a G31 specific hang when attempting to use linear 2048x2048 surfaces. Bonus! Fixes: Bug 25375 - Performance issue using texture from pixmap (tfp) glx extension on 945 http://bugs.freedesktop.org/show_bug.cgi?id=25375 Bug 27100 - GPU Hung copying a 2048x1152 pixmap http://bugs.freedesktop.org/show_bug.cgi?id=27100 Signed-off-by: Chris Wilson Tested-by: John --- src/i830_uxa.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) diff --git a/src/i830_uxa.c b/src/i830_uxa.c index fec53782..22792fea 100644 --- a/src/i830_uxa.c +++ b/src/i830_uxa.c @@ -135,8 +135,20 @@ i830_uxa_pixmap_compute_size(PixmapPtr pixmap, pitch_align = intel->accel_pixmap_pitch_alignment; size = ROUND_TO((w * pixmap->drawable.bitsPerPixel + 7) / 8, pitch_align) * ALIGN (h, 2); - if (size < 4096) + if (!IS_I965G(intel)) { + /* Older hardware requires fences to be pot size + * aligned with a minimum of 1 MiB, so causes + * massive overallocation for small textures. + */ + if (size < 1024*1024/2) + *tiling = I915_TILING_NONE; + } else if (size <= 4096) { + /* Disable tiling beneath a page size, we will not see + * any benefit from reducing TLB misses and instead + * just incur extra cost when we require a fence. + */ *tiling = I915_TILING_NONE; + } } repeat: @@ -863,11 +875,14 @@ i830_uxa_create_pixmap(ScreenPtr screen, int w, int h, int depth, return NullPixmap; } - if (usage == INTEL_CREATE_PIXMAP_TILING_X) - priv->tiling = I915_TILING_X; - else if (usage == INTEL_CREATE_PIXMAP_TILING_Y) + /* Always attempt to tile, compute_size() will remove the + * tiling for pixmaps that are either too large or too small + * to be effectively tiled. + */ + priv->tiling = I915_TILING_X; + if (usage == INTEL_CREATE_PIXMAP_TILING_Y) priv->tiling = I915_TILING_Y; - else + if (usage == UXA_CREATE_PIXMAP_FOR_MAP) priv->tiling = I915_TILING_NONE; size = i830_uxa_pixmap_compute_size(pixmap, w, h,