CVS commit: src

[Andrew Doran <ad%netbsd.org@localhost>]

Module Name:    src
Committed By:   ad
Date:           Fri Apr  4 17:25:10 UTC 2008

Modified Files:
        src/sys/kern: kern_rwlock.c
        src/usr.sbin/lockstat: main.c

Log Message:
Do adaptive spinning for rwlocks, but only if the lock is write held and
there are no waiters. This gives a major boost to build.sh on larger
systems as directory vnode locks are exclusive for lookup, but are often
only held for a very short period of time.

This change has the potential to more readily expose lock order reversals
and other types of deadlock.


To generate a diff of this commit:
cvs rdiff -r1.18 -r1.19 src/sys/kern/kern_rwlock.c
cvs rdiff -r1.11 -r1.12 src/usr.sbin/lockstat/main.c

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