[src/trunk]: src/lib/libc/sys Add a disclaimer if using on a multiprocessor m...

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

details:   https://anonhg.NetBSD.org/src/rev/c2cfb2edd4df
branches:  trunk
changeset: 536434:c2cfb2edd4df
user:      gmcgarry <gmcgarry%NetBSD.org@localhost>
date:      Sun Sep 15 23:05:13 2002 +0000

description:
Add a disclaimer if using on a multiprocessor machine.  Based on
comments by Bill Sommerfeld on tech-kern.

diffstat:

 lib/libc/sys/rasctl.2 |  9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)

diffs (23 lines):

diff -r 0d89aad8cbb1 -r c2cfb2edd4df lib/libc/sys/rasctl.2
--- a/lib/libc/sys/rasctl.2     Sun Sep 15 21:55:41 2002 +0000
+++ b/lib/libc/sys/rasctl.2     Sun Sep 15 23:05:13 2002 +0000
@@ -1,4 +1,4 @@
-.\"     $NetBSD: rasctl.2,v 1.3 2002/09/01 02:50:33 gmcgarry Exp $
+.\"     $NetBSD: rasctl.2,v 1.4 2002/09/15 23:05:13 gmcgarry Exp $
 .\"
 .\" Copyright (c) 2002 The NetBSD Foundation, Inc.
 .\" All rights reserved.
@@ -104,6 +104,13 @@
 Remove all registers sequences for this process.
 .El
 .Pp
+The RAS_PURGE and RAS_PURGE_ALL operations should be considered to have
+undefined behaviour if there are any other runnable threads in the
+address space which might be executing within the restartable atomic
+sequence(s) at the time of the purge.  The caller must be responsible
+for ensuring that there is some form of coordination with other threads
+to prevent unexpected behaviour.
+.Pp
 To preserve the atomicity of sequences, the kernel attempts to protect
 the sequences from alteration by the
 .Xr ptrace 2