Keeping it in VRAM wastes CPU time, because cursor_set ioctl reads handed BO back to RAM, just to write it to actual cursor BO.
Here (nv92/core i7), this patch decreases overall cpu usage of drmmode_load_cursor_argb from 4.6ms to ~90us and lets nv50_crtc_cursor_set disappear from perf traces. --- I considered accelerating kernel-side copying with GPU, but it turns out that: - it's slower (120-150us), with frequent bursts (up to 5ms) - not applicable to <nv50 hw, which needs to transform cursor data Putting cursor BO in GART does not conflict with accelarating kernel side copying - times do not change, so it's safe to apply it. --- src/drmmode_display.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/drmmode_display.c b/src/drmmode_display.c index 4d2d09d..ee0805d 100644 --- a/src/drmmode_display.c +++ b/src/drmmode_display.c @@ -567,7 +567,7 @@ drmmode_crtc_init(ScrnInfoPtr pScrn, drmmode_ptr drmmode, int num) drmmode->mode_res->crtcs[num]); drmmode_crtc->drmmode = drmmode; - ret = nouveau_bo_new(pNv->dev, NOUVEAU_BO_VRAM | NOUVEAU_BO_MAP, 0, + ret = nouveau_bo_new(pNv->dev, NOUVEAU_BO_GART | NOUVEAU_BO_MAP, 0, 64*64*4, NULL, &drmmode_crtc->cursor); assert(ret == 0); -- _______________________________________________ Nouveau mailing list Nouveau@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/nouveau