Module Name: src
Committed By: ahoka
Date: Tue Sep 14 21:35:53 UTC 2010
Modified Files:
src/share/man/man9: mutex.9
Log Message:
add a note on IPL and spinning mutexes
TODO: explain when the IPL will be restored
To generate a diff of this commit:
cvs rdiff -u -r1.22 -r1.23 src/share/man/man9/mutex.9
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/share/man/man9/mutex.9
diff -u src/share/man/man9/mutex.9:1.22 src/share/man/man9/mutex.9:1.23
--- src/share/man/man9/mutex.9:1.22 Tue Feb 16 19:21:30 2010
+++ src/share/man/man9/mutex.9 Tue Sep 14 21:35:53 2010
@@ -1,4 +1,4 @@
-.\" $NetBSD: mutex.9,v 1.22 2010/02/16 19:21:30 rmind Exp $
+.\" $NetBSD: mutex.9,v 1.23 2010/09/14 21:35:53 ahoka Exp $
.\"
.\" Copyright (c) 2007, 2009 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 February 16, 2010
+.Dd September 14, 2010
.Dt MUTEX 9
.Os
.Sh NAME
@@ -162,6 +162,11 @@
.Pp
Adaptive mutexes and other types of lock that can sleep may
not be acquired while a spin mutex is held by the caller.
+.Pp
+When acquiring a spin mutex, the IPL of the current CPU will be raised to
+the level set in
+.Fn mutex_init
+if it is not already equal or higher.
.It Fn mutex_exit "mtx"
.Pp
Release a mutex.
