Roughly half of a typical pmap_mincore() implementation is machine-

independent code.  Move this code into mincore(), and eliminate the
page queues lock from pmap_mincore().

Push down the page queues lock into pmap_clear_modify(),
pmap_clear_reference(), and pmap_is_modified().  Assert that these
functions are never passed an unmanaged page.

Eliminate an inaccurate comment from powerpc/powerpc/mmu_if.m:
Contrary to what the comment says, pmap_mincore() is not simply an
optimization.  Without a complete pmap_mincore() implementation,
mincore() cannot return either MINCORE_MODIFIED or MINCORE_REFERENCED
because only the pmap can provide this information.

Eliminate the page queues lock from vfs_setdirty_locked_object(),
vm_pageout_clean(), vm_object_page_collect_flush(), and
vm_object_page_clean().  Generally speaking, these are all accesses
to the page's dirty field, which are synchronized by the containing
vm object's lock.

Reduce the scope of the page queues lock in vm_object_madvise() and
vm_page_dontneed().

Reviewed by:	kib (an earlier version)

1 files changed, 2 insertions, 1 deletions

diff --git a/sys/vm/pmap.h b/sys/vm/pmap.h
index e4d8e81..82f88c9 100644
--- a/sys/vm/pmap.h
+++ b/sys/vm/pmap.h
@@ -122,6 +122,8 @@ boolean_t	 pmap_is_prefaultable(pmap_t pmap, vm_offset_t va);
 boolean_t	 pmap_is_referenced(vm_page_t m);
 boolean_t	 pmap_ts_referenced(vm_page_t m);
 vm_offset_t	 pmap_map(vm_offset_t *, vm_paddr_t, vm_paddr_t, int);
+int		 pmap_mincore(pmap_t pmap, vm_offset_t addr,
+		    vm_paddr_t *locked_pa);
 void		 pmap_object_init_pt(pmap_t pmap, vm_offset_t addr,
 		    vm_object_t object, vm_pindex_t pindex, vm_size_t size);
 boolean_t	 pmap_page_exists_quick(pmap_t pmap, vm_page_t m);
@@ -141,7 +143,6 @@ void		 pmap_sync_icache(pmap_t, vm_offset_t, vm_size_t);
 void		 pmap_zero_page(vm_page_t);
 void		 pmap_zero_page_area(vm_page_t, int off, int size);
 void		 pmap_zero_page_idle(vm_page_t);
-int		 pmap_mincore(pmap_t pmap, vm_offset_t addr);
 void		 pmap_activate(struct thread *td);
 
 #define	pmap_resident_count(pm)	((pm)->pm_stats.resident_count)