NetBSD/share/man/man9/preempt.9

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.\" $NetBSD: preempt.9,v 1.6 2008/04/30 13:10:58 martin Exp $
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.Dd July 3, 2007
.Dt PREEMPT 9
.Os
.Sh NAME
.Nm preempt ,
.Nm yield
.Nd general preempt and yield functions
.Sh SYNOPSIS
.In sys/sched.h
.Ft void
.Fn preempt "void"
.In sys/proc.h
.Ft void
.Fn yield "void"
.Sh DESCRIPTION
The
.Fn preempt
function puts the current LWP back on the system run queue
and performs an involuntary context switch.
The
.Fn yield
function is mostly same as
.Fn preempt ,
except that it performs a voluntary context switch.
.Pp
These functions drop the kernel lock before switching
and re-acquire it before returning.