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¶
The
vm_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¶
vm_page_unwire(9),
vm_page_wire(9)
AUTHORS¶
This manual page was written by
Chad David
⟨davidc@acns.ab.ca⟩.