[src/trunk]: src/sys/uvm uvm_pageidlezero: grab kernel_lock before uvm.fpageq...

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

details:   https://anonhg.NetBSD.org/src/rev/1ddb19032682
branches:  trunk
changeset: 570678:1ddb19032682
user:      yamt <yamt%NetBSD.org@localhost>
date:      Sat Oct 23 21:29:27 2004 +0000

description:
uvm_pageidlezero: grab kernel_lock before uvm.fpageqlock.  PR/27259.

diffstat:

 sys/uvm/uvm_page.c |  29 +++++++++++++++--------------
 1 files changed, 15 insertions(+), 14 deletions(-)

diffs (91 lines):

diff -r 5cc91ac6a053 -r 1ddb19032682 sys/uvm/uvm_page.c
--- a/sys/uvm/uvm_page.c        Sat Oct 23 21:27:33 2004 +0000
+++ b/sys/uvm/uvm_page.c        Sat Oct 23 21:29:27 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uvm_page.c,v 1.100 2004/09/17 20:46:03 yamt Exp $      */
+/*     $NetBSD: uvm_page.c,v 1.101 2004/10/23 21:29:27 yamt Exp $      */
 
 /*
  * Copyright (c) 1997 Charles D. Cranor and Washington University.
@@ -71,7 +71,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uvm_page.c,v 1.100 2004/09/17 20:46:03 yamt Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uvm_page.c,v 1.101 2004/10/23 21:29:27 yamt Exp $");
 
 #include "opt_uvmhist.h"
 
@@ -1550,32 +1550,29 @@
        int free_list, s, firstbucket;
        static int nextbucket;
 
+       KERNEL_LOCK(LK_EXCLUSIVE | LK_CANRECURSE);
        s = uvm_lock_fpageq();
        firstbucket = nextbucket;
        do {
-               if (sched_whichqs != 0) {
-                       uvm_unlock_fpageq(s);
-                       return;
-               }
+               if (sched_whichqs != 0)
+                       goto quit;
                if (uvmexp.zeropages >= UVM_PAGEZERO_TARGET) {
                        uvm.page_idle_zero = FALSE;
-                       uvm_unlock_fpageq(s);
-                       return;
+                       goto quit;
                }
                for (free_list = 0; free_list < VM_NFREELIST; free_list++) {
                        pgfl = &uvm.page_free[free_list];
                        while ((pg = TAILQ_FIRST(&pgfl->pgfl_buckets[
                            nextbucket].pgfl_queues[PGFL_UNKNOWN])) != NULL) {
-                               if (sched_whichqs != 0) {
-                                       uvm_unlock_fpageq(s);
-                                       return;
-                               }
+                               if (sched_whichqs != 0)
+                                       goto quit;
 
                                TAILQ_REMOVE(&pgfl->pgfl_buckets[
                                    nextbucket].pgfl_queues[PGFL_UNKNOWN],
                                    pg, pageq);
                                uvmexp.free--;
                                uvm_unlock_fpageq(s);
+                               KERNEL_UNLOCK();
 #ifdef PMAP_PAGEIDLEZERO
                                if (!PMAP_PAGEIDLEZERO(VM_PAGE_TO_PHYS(pg))) {
 
@@ -1586,20 +1583,22 @@
                                         * process now ready to run.
                                         */
 
+                                       KERNEL_LOCK(
+                                           LK_EXCLUSIVE | LK_CANRECURSE);
                                        s = uvm_lock_fpageq();
                                        TAILQ_INSERT_HEAD(&pgfl->pgfl_buckets[
                                            nextbucket].pgfl_queues[
                                            PGFL_UNKNOWN], pg, pageq);
                                        uvmexp.free++;
                                        uvmexp.zeroaborts++;
-                                       uvm_unlock_fpageq(s);
-                                       return;
+                                       goto quit;
                                }
 #else
                                pmap_zero_page(VM_PAGE_TO_PHYS(pg));
 #endif /* PMAP_PAGEIDLEZERO */
                                pg->flags |= PG_ZERO;
 
+                               KERNEL_LOCK(LK_EXCLUSIVE | LK_CANRECURSE);
                                s = uvm_lock_fpageq();
                                TAILQ_INSERT_HEAD(&pgfl->pgfl_buckets[
                                    nextbucket].pgfl_queues[PGFL_ZEROS],
@@ -1610,5 +1609,7 @@
                }
                nextbucket = (nextbucket + 1) & uvmexp.colormask;
        } while (nextbucket != firstbucket);
+quit:
        uvm_unlock_fpageq(s);
+       KERNEL_UNLOCK();
 }