On Tue, Oct 22, 2013 at 01:15:32PM +0100, Chris Wilson wrote: > On Tue, Oct 22, 2013 at 12:04:17PM +0000, Siluvery, Arun wrote: > > From: "Siluvery, Arun" <arun.siluvery@xxxxxxxxx> > > > > When a mapping is requested and if there is no space the mapping fails > > and the region is not physically backed. This results in > > signal 7(SIGBUS), code 2 (BUS_ADRERR) when it is actually accessed. > > This patch handles this error, continues to wait and retries to find space. > > Eh, no. The line before will remove everything from the aperture that is > unpinned. Throwing an evict_everything in here breaks reservations, so I > think you are just papering over a bug. If we want to fix this for real (i.e. allow userspace to reliably map stuff, mabye even bigger than the aperture) we need to fall back to suballocating tile-row aligned strides of the buffer (maybe pick the tile row multiply in between 1M-2M). Until that's done userspace can't rely on gtt mmaps relibly working for large buffers. The current heuristics we're using is half of the mappable space, but that's probably a bit too optimistic. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
