[src/trunk]: src/sys/kern bt_refill is and must be called with VM_NOSLEEP set...

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

details:   https://anonhg.NetBSD.org/src/rev/5f99623b8222
branches:  trunk
changeset: 328406:5f99623b8222
user:      para <para%NetBSD.org@localhost>
date:      Wed Apr 02 16:14:50 2014 +0000

description:
bt_refill is and must be called with VM_NOSLEEP set, assert this
fix error path if pool_get returns NULL

diffstat:

 sys/kern/subr_vmem.c |  15 ++++++++-------
 1 files changed, 8 insertions(+), 7 deletions(-)

diffs (54 lines):

diff -r 77a7c484560d -r 5f99623b8222 sys/kern/subr_vmem.c
--- a/sys/kern/subr_vmem.c      Wed Apr 02 15:45:51 2014 +0000
+++ b/sys/kern/subr_vmem.c      Wed Apr 02 16:14:50 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: subr_vmem.c,v 1.90 2014/03/20 06:48:22 mlelstv Exp $   */
+/*     $NetBSD: subr_vmem.c,v 1.91 2014/04/02 16:14:50 para Exp $      */
 
 /*-
  * Copyright (c)2006,2007,2008,2009 YAMAMOTO Takashi,
@@ -46,7 +46,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: subr_vmem.c,v 1.90 2014/03/20 06:48:22 mlelstv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_vmem.c,v 1.91 2014/04/02 16:14:50 para Exp $");
 
 #if defined(_KERNEL)
 #include "opt_ddb.h"
@@ -230,6 +230,8 @@
 {
        bt_t *bt;
 
+       KASSERT(flags & VM_NOSLEEP);
+
        VMEM_LOCK(vm);
        if (vm->vm_nfreetags > BT_MINRESERVE) {
                VMEM_UNLOCK(vm);
@@ -251,22 +253,21 @@
        while (vm->vm_nfreetags <= BT_MINRESERVE) {
                VMEM_UNLOCK(vm);
                mutex_enter(&vmem_btag_refill_lock);
-               bt = pool_get(&vmem_btag_pool,
-                   (flags & VM_SLEEP) ? PR_WAITOK: PR_NOWAIT);
+               bt = pool_get(&vmem_btag_pool, PR_NOWAIT);
                mutex_exit(&vmem_btag_refill_lock);
                VMEM_LOCK(vm);
-               if (bt == NULL && (flags & VM_SLEEP) == 0)
+               if (bt == NULL)
                        break;
                LIST_INSERT_HEAD(&vm->vm_freetags, bt, bt_freelist);
                vm->vm_nfreetags++;
        }
 
-       VMEM_UNLOCK(vm);
-
        if (vm->vm_nfreetags == 0) {
+               VMEM_UNLOCK(vm);
                return ENOMEM;
        }
 
+       VMEM_UNLOCK(vm);
 
        if (kmem_meta_arena != NULL) {
                bt_refill(kmem_arena, (flags & ~VM_FITMASK)