NAME
vm_page_hold,
vm_page_unhold —
update a page's hold count
SYNOPSIS
#include
<sys/param.h>
#include <vm/vm.h>
#include <vm/vm_page.h>
void
vm_page_hold(vm_page_t
m);
void
vm_page_unhold(vm_page_t
m);
DESCRIPTION
Thevm_page_hold()
function increases the hold count on a page. This prevents the page daemon
from freeing the page.
vm_page_hold()
should only be used for very temporary wiring of a page, as that page will
not be considered for paging or reallocation for as long as its hold count
is greater than zero. Also note that while wired pages are removed from
whatever queue they are on, vm_page_hold() does not
affect the location of the page. If it is on a queue prior to the call, it
will still be there afterward.
If the page needs to be held for a long period of time, vm_page_wire(9) should be used.
vm_page_unhold()
function reduces the hold count on a page. If the hold count is zero it is
possible that the page will be freed by the page daemon.
SEE ALSO
AUTHORS
This manual page was written by Chad David <davidc@acns.ab.ca>.