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.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved.
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.\" $FreeBSD: src/share/man/man9/vm_page_wakeup.9,v 1.3.10.3.2.1 2010/12/21 17:09:25 kensmith Exp $
.\"
.Dd July 14, 2001
.Dt VM_PAGE_BUSY 9
.Os
.Sh NAME
.Nm vm_page_busy ,
.Nm vm_page_flash ,
.Nm vm_page_wakeup
.Nd "handle the busying and unbusying of a page"
.Sh SYNOPSIS
.In sys/param.h
.In vm/vm.h
.In vm/vm_page.h
.Ft void
.Fn vm_page_busy "vm_page_t m"
.Ft void
.Fn vm_page_flash "vm_page_t m"
.Ft void
.Fn vm_page_wakeup "vm_page_t m"
.Sh DESCRIPTION
These functions handle the busying, unbusying and notification of the unbusying
of a page.
.Pp
.Fn vm_page_busy
sets the
.Dv VPO_BUSY
flag in the page.
.Pp
.Fn vm_page_flash
checks to see if there is anybody waiting on the page
.Dv ( VPO_WANTED
will be set), and if so, clears the
.Dv VPO_WANTED
flag and notifies whoever is waiting via
.Fn wakeup .
.Pp
.Fn vm_page_wakeup
clears the
.Dv VPO_BUSY
flag on the page, and calls
.Fn vm_page_flash
in case somebody has been waiting for it.
.Sh SEE ALSO
.Xr vm_page_sleep_if_busy 9 ,
.Xr wakeup 9
.Sh AUTHORS
This manual page was written by
.An Chad David Aq davidc@acns.ab.ca .