Update LICENCE.

FreeBSD: Upgrade to FreeBSD-releng-13.0 compiled, to be tested.

kern_timeout: decrease the cpu usage of timer.

There's a bug of last version, every tick, the timer will traverse all the
entries in callwheel, when lots of connections comming, the callout
process

kern_timeout: decrease the cpu usage of timer.

There's a bug of last version, every tick, the timer will traverse all the
entries in callwheel, when lots of connections comming, the callout
process will use lots of cpu resources.

This commit fixes it, every tick, check the bucket which is hashed with current
tick, if there are entries, compare the callout tick, and invoke
callbacks.

show more ...

kern_timeout: decrease the cpu usage of timer.

There's a bug of last version, every tick, the timer will traverse all the
entries in callwheel, when lots of connections comming, the callout
process

kern_timeout: decrease the cpu usage of timer.

There's a bug of last version, every tick, the timer will traverse all the
entries in callwheel, when lots of connections comming, the callout
process will use lots of cpu resources.

This commit fixes it, every tick, check the bucket which is hashed with current
tick, if there are entries, compare the callout tick, and invoke
callbacks.

show more ...

ff_kern_timeout: optimize the timecounter.

This timecounter implementation retrieves the current time and reports it
as the equivalent number of counts from a counter incrementing at 'hz'.

ff_kern_timeout: optimize the timecounter.

This timecounter implementation retrieves the current time and reports it
as the equivalent number of counts from a counter incrementing at 'hz'.

Fix typo.

init