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Diffstat (limited to 'share/man/man9/vm_page_wire.9')
| -rw-r--r-- | share/man/man9/vm_page_wire.9 | 52 |
1 files changed, 34 insertions, 18 deletions
diff --git a/share/man/man9/vm_page_wire.9 b/share/man/man9/vm_page_wire.9 index 4722f71bdc6a..e3f03ab6b1f8 100644 --- a/share/man/man9/vm_page_wire.9 +++ b/share/man/man9/vm_page_wire.9 @@ -26,12 +26,13 @@ .\" .\" $FreeBSD$ .\" -.Dd July 13, 2001 +.Dd September 9, 2019 .Dt VM_PAGE_WIRE 9 .Os .Sh NAME .Nm vm_page_wire , -.Nm vm_page_unwire +.Nm vm_page_unwire , +.Nm vm_page_unwire_noq .Nd "wire and unwire pages" .Sh SYNOPSIS .In sys/param.h @@ -39,29 +40,44 @@ .In vm/vm_page.h .Ft void .Fn vm_page_wire "vm_page_t m" +.Ft bool +.Fn vm_page_wire_mapped "vm_page_t m" .Ft void -.Fn vm_page_unwire "vm_page_t m" "int activate" +.Fn vm_page_unwire "vm_page_t m" "int queue" +.Ft bool +.Fn vm_page_unwire_noq "vm_page_t m" .Sh DESCRIPTION The .Fn vm_page_wire -function increments the wire count on a page, and removes it from -whatever queue it is on. +and +.Fn vm_page_wire_mapped +function wire the page, prevent it from being reclaimed by the page +daemon or when its containing object is destroyed. +Both functions require that the page belong to an object. +The +.Fn vm_page_wire_mapped +function is for use by the +.Xr pmap 9 +layer following a lookup. +This function may fail if mappings of the page are concurrently +being destroyed, in which case it will return false. .Pp The .Fn vm_page_unwire -function releases one of the wirings on the page. -When -.Va write_count -reaches zero the page is placed back onto either the active queue -(if -.Fa activate -is non-zero) or onto the inactive queue (if -.Fa activate -is zero). -If the page is unmanaged -.Dv ( PG_UNMANAGED -is set) then the page is left on -.Dv PQ_NONE . +and +.Fn vm_page_unwire_noq +functions release a wiring of a page. +The +.Fn vm_page_unwire +function takes a queue index and will insert the page into the +corresponding page queue upon releasing its last wiring. +If the page does not belong to an object and no other references +to the page exist, +.Fn vm_page_unwire +will free the page. +.Fn vm_page_unwire_noq +releases the wiring and returns true if it was the last wiring +of the page. .Sh AUTHORS This manual page was written by .An Chad David Aq Mt davidc@acns.ab.ca . |