CVS commit: src/sys/kern

["Taylor R Campbell" <riastradh%netbsd.org@localhost>]

Module Name:    src
Committed By:   riastradh
Date:           Fri Feb 24 11:01:44 UTC 2023

Modified Files:
        src/sys/kern: kern_rwlock.c

Log Message:
rwlock(9): Fix membars.

rw_downgrade must be a release operation, and rw_tryupgrade must be
an acquire operation.  membar_producer is not enough -- need to use
membar_release and membar_acquire.

Discussed on tech-kern:
https://mail-index.netbsd.org/tech-kern/2023/02/22/msg028726.html

XXX pullup-8
XXX pullup-9
XXX pullup-10


To generate a diff of this commit:
cvs rdiff -u -r1.67 -r1.68 src/sys/kern/kern_rwlock.c

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