diff options
Diffstat (limited to 'src/nouveau_dri2.c')
| -rw-r--r-- | src/nouveau_dri2.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/src/nouveau_dri2.c b/src/nouveau_dri2.c index f0c7fec..7878a5a 100644 --- a/src/nouveau_dri2.c +++ b/src/nouveau_dri2.c @@ -445,6 +445,26 @@ nouveau_dri2_schedule_swap(ClientPtr client, DrawablePtr draw, if (*target_msc == 0) *target_msc = 1; +#if DRI2INFOREC_VERSION >= 6 + /* Is this a swap in the future, ie. the vblank event will + * not be immediately dispatched, but only at a future vblank? + * If so, we need to temporarily lower the swaplimit to 1, so + * that DRI2GetBuffersWithFormat() requests from the client get + * deferred in the x-server until the vblank event has been + * dispatched to us and nouveau_dri2_finish_swap() is done. If + * we wouldn't do this, DRI2GetBuffersWithFormat() would operate + * on wrong (pre-swap) buffers, and cause a segfault later on in + * nouveau_dri2_finish_swap(). Our vblank event handler restores + * the old swaplimit immediately after nouveau_dri2_finish_swap() + * is done, so we still get 1 video refresh cycle worth of + * triple-buffering. For a swap at next vblank, dispatch of the + * vblank event happens immediately, so there isn't any need + * for this lowered swaplimit. + */ + if (current_msc < *target_msc - 1) + DRI2SwapLimit(draw, 1); +#endif + /* Request a vblank event one frame before the target */ ret = nouveau_wait_vblank(draw, DRM_VBLANK_ABSOLUTE | DRM_VBLANK_EVENT, @@ -557,6 +577,12 @@ nouveau_dri2_vblank_handler(int fd, unsigned int frame, switch (s->action) { case SWAP: nouveau_dri2_finish_swap(draw, frame, tv_sec, tv_usec, s); +#if DRI2INFOREC_VERSION >= 6 + /* Restore real swap limit on drawable, now that it is safe. */ + ScrnInfoPtr scrn = xf86Screens[draw->pScreen->myNum]; + DRI2SwapLimit(draw, NVPTR(scrn)->swap_limit); +#endif + break; case WAIT: |