[src/trunk]: src/share/man/man9 Be explcit that all calls to pmap_activate() ...

[thorpej <thorpej%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/56cdf22b6ca8
branches:  trunk
changeset: 974913:56cdf22b6ca8
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Sun Aug 16 16:48:08 2020 +0000

description:
Be explcit that all calls to pmap_activate() and pmap_deactivate()
from MI code are made with preemption disabled and with l == curlwp.

diffstat:

 share/man/man9/pmap.9 |  22 ++++++++++------------
 1 files changed, 10 insertions(+), 12 deletions(-)

diffs (55 lines):

diff -r 7a7c1b9462c4 -r 56cdf22b6ca8 share/man/man9/pmap.9
--- a/share/man/man9/pmap.9     Sun Aug 16 16:01:35 2020 +0000
+++ b/share/man/man9/pmap.9     Sun Aug 16 16:48:08 2020 +0000
@@ -1,4 +1,4 @@
-.\"    $NetBSD: pmap.9,v 1.47 2020/03/14 14:05:42 ad Exp $
+.\"    $NetBSD: pmap.9,v 1.48 2020/08/16 16:48:08 thorpej Exp $
 .\"
 .\" Copyright (c) 2000, 2001, 2002, 2020 The NetBSD Foundation, Inc.
 .\" All rights reserved.
@@ -27,7 +27,7 @@
 .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 .\" POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd March 14, 2020
+.Dd August 16, 2020
 .Dt PMAP 9
 .Os
 .Sh NAME
@@ -766,18 +766,16 @@
 .It void Fn "pmap_activate" "struct lwp *l"
 Activate the physical map used by the process behind lwp
 .Fa l .
+on the current CPU.
 This is called by the virtual memory system when the
 virtual memory context for a process is changed, and is also
-often used by machine-dependent context switch code to program
-the memory management hardware with the process's page table
-base, etc.
-Note that
+used by the context switch code to program the memory management hardware
+with the process's page table base, etc.
+All calls to
 .Fn pmap_activate
-may not always be called when
+from machine-independent code are made with preemption disabled and with
 .Fa l
-is the current lwp.
-.Fn pmap_activate
-must be able to handle this scenario.
+as the current lwp.
 .Pp
 The
 .Fn pmap_activate
@@ -792,9 +790,9 @@
 Like
 .Fn pmap_activate ,
 .Fn pmap_deactivate
-may not always be called when
+is called by machine-independent code with preemption disabled and with
 .Fa l
-is the current lwp.
+as the current lwp.
 .Pp
 As above,
 .Fn pmap_deactivate