cvs commit: src/sys/kern kern_rwlock.c src/sys/sys rwlock.h

[John Baldwin]

jhb         2006-04-19 21:06:52 UTC

  FreeBSD src repository

  Modified files:
    sys/kern             kern_rwlock.c 
    sys/sys              rwlock.h 
  Log:
  Implement rw_try_upgrade() and rw_downgrade().  rw_try_upgrade() makes a
  single attempt at upgrading a read lock to a write lock, and rw_downgrade()
  converts curthread's write lock into a read lock.
  
  Revision  Changes    Path
  1.9       +133 -2    src/sys/kern/kern_rwlock.c
  1.3       +5 -1      src/sys/sys/rwlock.h