[src/trunk]: src/sys/uvm uvm_fault_upper_lookup, uvm_fault_upper_neighbor: Th...

[uebayasi <uebayasi%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/b3d43c7dbbd8
branches:  trunk
changeset: 752350:b3d43c7dbbd8
user:      uebayasi <uebayasi%NetBSD.org@localhost>
date:      Wed Feb 24 06:18:19 2010 +0000

description:
uvm_fault_upper_lookup, uvm_fault_upper_neighbor: There is no point to call
pmap_update() without calling pmap_enter().

(Probably calling only once after loop (as done in uvm_fault_lower_lookup())
is enough.  If done so, other threads see entered neighbor pages as reflected
a little latter.)

diffstat:

 sys/uvm/uvm_fault.c |  19 +++++++++----------
 1 files changed, 9 insertions(+), 10 deletions(-)

diffs (54 lines):

diff -r a48741225d63 -r b3d43c7dbbd8 sys/uvm/uvm_fault.c
--- a/sys/uvm/uvm_fault.c       Wed Feb 24 06:05:35 2010 +0000
+++ b/sys/uvm/uvm_fault.c       Wed Feb 24 06:18:19 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uvm_fault.c,v 1.171 2010/02/24 05:26:28 uebayasi Exp $ */
+/*     $NetBSD: uvm_fault.c,v 1.172 2010/02/24 06:18:19 uebayasi Exp $ */
 
 /*
  *
@@ -39,7 +39,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uvm_fault.c,v 1.171 2010/02/24 05:26:28 uebayasi Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uvm_fault.c,v 1.172 2010/02/24 06:18:19 uebayasi Exp $");
 
 #include "opt_uvmhist.h"
 
@@ -1111,8 +1111,13 @@
                        struct vm_anon *anon = anons[lcv];
 
                        mutex_enter(&anon->an_lock);
-                       uvm_fault_upper_neighbor(ufi, flt, currva,
-                           anon->an_page, anon->an_ref > 1);
+                       struct vm_page *pg = anon->an_page;
+
+                       /* ignore loaned and busy pages */
+                       if (pg != NULL && pg->loan_count == 0 &&
+                           (pg->flags & PG_BUSY) == 0)
+                               uvm_fault_upper_neighbor(ufi, flt, currva,
+                                   pg, anon->an_ref > 1);
                        mutex_exit(&anon->an_lock);
                }
        }
@@ -1141,11 +1146,6 @@
 {
        UVMHIST_FUNC("uvm_fault_upper_neighbor"); UVMHIST_CALLED(maphist);
 
-       /* ignore loaned and busy pages */
-       if (pg == NULL || pg->loan_count != 0 ||
-           (pg->flags & PG_BUSY) != 0)
-               goto uvm_fault_upper_lookup_enter_done;
-
        mutex_enter(&uvm_pageqlock);
        uvm_pageenqueue(pg);
        mutex_exit(&uvm_pageqlock);
@@ -1166,7 +1166,6 @@
            flt->enter_prot,
            PMAP_CANFAIL | (flt->wire_mapping ? PMAP_WIRED : 0));
 
-uvm_fault_upper_lookup_enter_done:
        pmap_update(ufi->orig_map->pmap);
 }