We want to be able to use the bufmgr from multiple threads for GL, and thus
we need to protect the internal structures.
The pthread-stubs package is used so that programs not linked against
pthreads get weak symbols to stubs and don't eat most of the cost.
I'd swapped the operands, so if we weren't in lockstep with the hardware we
said the sequence was always passed. Additionally, a race was available that
we might have failed at recovering from. Instead, I've replaced the logic
with new stuff that should be more robust and not rely on all the parties in
userland following the same IRQ_EMIT() == 1 protocol. Also, in a radical
departure from past efforts, include a long comment describing the failure
modes and how we're working around them.
Thanks to haihao for catching the original issue.
dri_bufmgr.h is replaced by intel_bufmgr.h, and several functions are renamed,
though the structures and many functions remain dri_bufmgr_* and dri_bo_*
This is the create (may want location flags), pread/pwrite/mmap
(performance tuning hints), and set_domain (will 32 bits be enough for
everyone?) ioctls. Left in the generic set are just flink/open/close.
The 2D driver must be updated for this change, and API but not ABI is broken
for 3D. The driver version is bumped to mark this.
Eric Anholt
Dave Airlie
Xiang, Haihao