.\"     $NetBSD: preempt.9,v 1.4 2005/12/20 19:34:43 rpaulo Exp $
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.\" by Gregory McGarry.
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.Dd December 20, 2005
.Dt PREEMPT 9
.Os
.Sh NAME
.Nm preempt
.Nd general preempt function
.Sh SYNOPSIS
.In sys/sched.h
.Ft void
.Fn preempt "int more"
.Sh DESCRIPTION
The
.Fn preempt
function puts the current process back on the system run queue
and performs an involuntary context switch.
If the specified argument
.Fa more
is not
.Dv 0
then a "voluntary" preemption is made, using
.Fn sa_preempt .
.Xr mi_switch 9
is used to select the new process.
.Pp
The
.Fn preempt
function must not be called with the scheduler lock held.
.Sh SEE ALSO
.Xr mi_switch 9 ,
.Xr setrunqueue 9 ,
.Xr userret 9