CVS commit: src

["Juergen Hannken-Illjes" <hannken%netbsd.org@localhost>]

Module Name:    src
Committed By:   hannken
Date:           Thu Dec  1 14:49:04 UTC 2016

Modified Files:
        src/sys/kern: vfs_vnode.c
        src/tests/fs/puffs: t_basic.c

Log Message:
- Change vcache_reclaim() to always call VOP_INACTIVE() before VOP_RECLAIM().
  When called from vrecycle() or vgone() there is a window where the refcount
  is greater than zero and another thread could get and release a reference
  that would miss VOP_INACTIVE() as the refcount doesn't drop to zero.

  Adjust test fs/puffs/t_basic:  test VOP_INACTIVE count being greater zero.

- Make vrecycle() more robust by checking v_usecount first and preventing
  further references across vn_lock().  Fixes a deadlock where one thread
  starts unmount, second thread locks a directory and allocates a vnode
  and first thread tries to vrecycle() the directory.
  First thread holds vfs_busy and wants vnode, second thread holds vnode
  and wants vfs_busy.

- With these fixes in place change cleanvnode() to use vget()/vrecycle()
  to reclaim the vnode.


To generate a diff of this commit:
cvs rdiff -u -r1.59 -r1.60 src/sys/kern/vfs_vnode.c
cvs rdiff -u -r1.12 -r1.13 src/tests/fs/puffs/t_basic.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.