Some few zalloc calls to objcache ones replacements
There are two parts of this patch:
1) Which translates sys/netbt from the zone(9) to objcache(9): Why are you using objcache_dtor() instead of objcache_put() in the send/receive paths? Also, have you tried this changes with bluetooth(4)? Does it work properly?
2) Use objcache(9) for the swap pager. Probably not a good idea. After checking with Matt the pager has special requirements and it has to rely on zone(9).
Usually you'd send separate patches that can be logically divided by functionality or kernel subsystems that they deal with.