Module Name: src
Committed By: pooka
Date: Mon Mar 1 17:20:44 UTC 2010
Modified Files:
src/lib/librumpuser: rumpuser.3
Log Message:
Join today's manpage mania by updating this to reflect the current
situation a "little" better.
To generate a diff of this commit:
cvs rdiff -u -r1.1 -r1.2 src/lib/librumpuser/rumpuser.3
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/lib/librumpuser/rumpuser.3
diff -u src/lib/librumpuser/rumpuser.3:1.1 src/lib/librumpuser/rumpuser.3:1.2
--- src/lib/librumpuser/rumpuser.3:1.1 Fri Feb 26 18:54:20 2010
+++ src/lib/librumpuser/rumpuser.3 Mon Mar 1 17:20:44 2010
@@ -1,6 +1,6 @@
-.\" $NetBSD: rumpuser.3,v 1.1 2010/02/26 18:54:20 pooka Exp $
+.\" $NetBSD: rumpuser.3,v 1.2 2010/03/01 17:20:44 pooka Exp $
.\"
-.\" Copyright (c) 2008 Antti Kantee. All rights reserved.
+.\" Copyright (c) 2010 Antti Kantee. All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
@@ -23,28 +23,42 @@
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
-.Dd July 28, 2008
+.Dd March 1, 2010
.Dt RUMPUSER 3
.Os
.Sh NAME
.Nm rumpuser
-.Nd rump user namespace helper routines
+.Nd rump hypervisor interface
.Sh LIBRARY
rump User Library (librumpuser, \-lrumpuser)
.Sh SYNOPSIS
.In rump/rumpuser.h
.Sh DESCRIPTION
.Nm
-is a user namespace helper library for runnable userspace meta programs.
-From rump emulation code compiled with
-.Dv -D_KERNEL
-is it not possible to directly call routines such as system calls
-for reading and writing files or devices.
-This is where
+is the hypervisor interface for
+.Xr rump 3
+style kernel virtualization.
+A virtual rump kernel can make calls to the host operating system
+libraries and kernel (system calls) using
+.Nm
+interfaces.
+Any "slow" hypervisor calls such as file I/O, sychronization wait,
+or sleep will cause rump to unschedule the calling kernel thread
+from the virtual CPU and free it for other consumers.
+When the hypervisor call returns to the kernel, a new scheduling
+operation takes place.
+.Pp
+For example, rump implements kernel threads directly as hypervisor
+calls to host
+.Xr pthread 3 .
+This avoids the common virtualization drawback of multiple overlapping
+and possibly conflicting implementations of same functionality in
+the software stack.
+.Pp
+The
.Nm
-comes into play by providing a bridge between the two namespaces.
-Another example of its services is a way to call pthread routines,
-used for emulating kernel threads and synchronization mechanisms
-in rump.
+interface is still under development and interface documentation
+is available only in source form from
+.Pa src/lib/librumpuser .
.Sh SEE ALSO
.Xr rump 3
