Revise the interface between vm_object_madvise() and vm_page_dontneed() so

that pointless calls to pmap_is_modified() can be easily avoided when
performing madvise(..., MADV_FREE).

Sponsored by:	EMC / Isilon Storage Division

1 files changed, 2 insertions, 22 deletions

diff --git a/sys/vm/vm_object.c b/sys/vm/vm_object.c
index 9ddd141..97d8557 100644
--- a/sys/vm/vm_object.c
+++ b/sys/vm/vm_object.c
@@ -1175,28 +1175,8 @@ shadowlookup:
 		}
 		if (advise == MADV_WILLNEED) {
 			vm_page_activate(m);
-		} else if (advise == MADV_DONTNEED) {
-			vm_page_dontneed(m);
-		} else if (advise == MADV_FREE) {
-			/*
-			 * Mark the page clean.  This will allow the page
-			 * to be freed up by the system.  However, such pages
-			 * are often reused quickly by malloc()/free()
-			 * so we do not do anything that would cause
-			 * a page fault if we can help it.
-			 *
-			 * Specifically, we do not try to actually free
-			 * the page now nor do we try to put it in the
-			 * cache (which would cause a page fault on reuse).
-			 *
-			 * But we do make the page is freeable as we
-			 * can without actually taking the step of unmapping
-			 * it.
-			 */
-			pmap_clear_modify(m);
-			m->dirty = 0;
-			m->act_count = 0;
-			vm_page_dontneed(m);
+		} else {
+			vm_page_advise(m, advise);
 		}
 		vm_page_unlock(m);
 		if (advise == MADV_FREE && tobject->type == OBJT_SWAP)