K 10
svn:author
V 7
attilio
K 8
svn:date
V 27
2007-06-26T21:42:01.000000Z
K 7
svn:log
V 627
Fix an old standing LOR between callout_lock and sleepqueues chain (which
could lead to a deadlock).
- sleepq_set_timeout acquires callout_lock (via callout_reset()) only
  with sleepq chain lock held
- msleep_spin in _callout_stop_safe lock the sleepqueue chain with
  callout_lock held

In order to solve this don't use msleep_spin in _callout_stop_safe() but
use directly sleepqueues as inline msleep_spin code. Rearrange the
wakeup path in order to have it consistent too.

Reported by: kris (via stress2 test suite)
Tested by: Timothy Redaelli <drizzt@gufi.org>
Reviewed by: jhb
Approved by: jeff (mentor)
Approved by: re

END