svn commit: r324189 - head/sys/dev/md

[Alan Cox]

Author: alc
Date: Mon Oct  2 07:14:32 2017
New Revision: 324189
URL: https://svnweb.freebsd.org/changeset/base/324189

Log:
  When mdstart_swap() accesses a page that is already in the active queue,
  mark the page as referenced rather than calling vm_page_activate().  This
  allows the page's act_count to grow beyond ACT_INIT and better reflect
  its usage.  (See also r324146, which modified a function used by tmpfs,
  uiomove_object_page(), to behave in the same way.)
  
  Reviewed by:	kib, markj
  MFC after:	2 weeks

Modified:
  head/sys/dev/md/md.c

Modified: head/sys/dev/md/md.c
==============================================================================
--- head/sys/dev/md/md.c	Mon Oct  2 06:48:56 2017	(r324188)
+++ head/sys/dev/md/md.c	Mon Oct  2 07:14:32 2017	(r324189)
@@ -1111,7 +1111,10 @@ mdstart_swap(struct md_s *sc, struct bio *bp)
 		if (m != NULL) {
 			vm_page_xunbusy(m);
 			vm_page_lock(m);
-			vm_page_activate(m);
+			if (vm_page_active(m))
+				vm_page_reference(m);
+			else
+				vm_page_activate(m);
 			vm_page_unlock(m);
 		}