- Emulate Linux mutex API using sx(9) locks with only exclusive operations
instead of mutex(9), in Linux mutexes are sleepable.
- Emulate Linux rwlock_t using rwlock(9) instead of sx(9). rwlock_t
in Linux are spin locks
years for head. However, it is continuously misused as the mpsafe argument
for callout_init(9). Deprecate the flag and clean up callout_init() calls
to make them more consistent.
Differential Revision: https://reviews.freebsd.org/D2613
Reviewed by: jhb
MFC after: 2 weeks