qcacmn: Implement a freelist for net buf tracking
The net buf tracking feature spend most of its time allocating
tracking cookies. By not tracking these tracking cookies in
qdf we achieve a 90% time saving. By keeping a freelist and
avoiding allocations altoogether, we save another 90%. This
feature is 99% cheaper. Throughput suffers less under when
the driver is forced to be cpu bound (eg. by mucking with the clockspeed).
Change-Id: If3268bdbbcf39aeb7278b1e51e17955eb2b47510
CRs-Fixed: 1024277
2 files changed