Module Name: src
Committed By: yamt
Date: Mon Oct 24 07:25:51 UTC 2011
Modified Files:
src/share/man/man9: xcall.9
Log Message:
- document XC_HIGHPRI
- explicitly note that xc_wait requires thread context.
To generate a diff of this commit:
cvs rdiff -u -r1.7 -r1.8 src/share/man/man9/xcall.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/xcall.9
diff -u src/share/man/man9/xcall.9:1.7 src/share/man/man9/xcall.9:1.8
--- src/share/man/man9/xcall.9:1.7 Thu Dec 2 12:54:13 2010
+++ src/share/man/man9/xcall.9 Mon Oct 24 07:25:51 2011
@@ -1,4 +1,4 @@
-.\" $NetBSD: xcall.9,v 1.7 2010/12/02 12:54:13 wiz Exp $
+.\" $NetBSD: xcall.9,v 1.8 2011/10/24 07:25:51 yamt Exp $
.\"
.\" Copyright (c) 2010 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 May 16, 2010
+.Dd October 24, 2011
.Dt XCALL 9
.Os
.Sh NAME
@@ -81,6 +81,15 @@ context, and not from a software interru
not interrupting other code running on the CPU, and so has exclusive
access to the CPU.
Keep in mind that unless disabled, it may cause a kernel preemption.
+.Pp
+.Nm
+also provides a mechanism for making
+.Dq "high priority"
+cross calls.
+The function to be executed runs on the remote CPU within a
+.Dv IPL_SOFTCLOCK
+software interrupt context, possibly interrupting other lower-priority
+code running on the CPU.
.Sh NOTES
Functions being called should be relatively lightweight.
They may block on locks, but carefully and minimally, to not interfere
@@ -101,7 +110,9 @@ to
.Fn xc_wait
on for the cross-call to complete.
.Fa flags
-should be 0.
+should be
+.Dv XC_HIGHPRI
+for a "high priority" call, and 0 for a "low priority" call.
.Fn xc_broadcast
should not be called from interrupt context.
.It Fn xc_unicast "flags" "func" "arg1" "arg2" "ci"
@@ -122,6 +133,8 @@ returned by a prior
or
.Fn xc_unicast
for the corresponding cross-call to complete.
+.Fn xc_wait
+should be called from a thread context.
.El
.Sh CODE REFERENCES
The
