On Fri, Feb 27, 2015 at 10:22:10AM -0800, Ben Widawsky wrote: > From the comments in the code: > > Called from intel_batchbuffer_flush before emitting MI_BATCHBUFFER_END and > sending it off. > > This fixes a possible, unlikely infinite recursion in our batch flush path. > More > importantly it allows me to add some code here. > > The relevant part of the call chain for flush > intel_batchbuffer_flush()->brw_finish_batch(). The problem arises if anything > in > the time from intel_batchbuffer_flush, until brw_finish_batch ends up calling > itself. This can happen as a result of a call to > intel_batchbuffer_begin()->intel_batchbuffer_require_space()->intel_batchbuffer_flush(). > > There are two possible cases today which can spawn this recursion. > 1. There is a ring switch occurring (impossible, see below) > 2. The ring is out of space (fairly unlikely)
Just discussed this with krh. #2 cannot occur because of the BATCH_RESERVE. So only case #1 is possible, and only after the next patch. Also, there is probably a cleaner way to do this (I'm thinking modify the ring variable in a different place), but this is cleaner, and I'd like to see if it fixes anything first _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
