[src/trunk]: src/sys/uvm PR kern/48044: panic: kernel diagnostic assertion "u...

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

details:   https://anonhg.NetBSD.org/src/rev/7d00b4d46a94
branches:  trunk
changeset: 847529:7d00b4d46a94
user:      ad <ad%NetBSD.org@localhost>
date:      Fri Dec 27 00:46:38 2019 +0000

description:
PR kern/48044: panic: kernel diagnostic assertion "uvmexp.swpgonly + npages <= uvmexp.swpginuse" failed

swpgonly is updated asynchronously with regard to swap use.  We can't assert
this condition with confidence in the post-5.0 world, at least not without
broader changes.  swpgonly's ultimate use is of a heuristic nature so this
is no problem at all.

diffstat:

 sys/uvm/uvm_pager.c |  5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)

diffs (26 lines):

diff -r ecb091f7ffd5 -r 7d00b4d46a94 sys/uvm/uvm_pager.c
--- a/sys/uvm/uvm_pager.c       Fri Dec 27 00:35:05 2019 +0000
+++ b/sys/uvm/uvm_pager.c       Fri Dec 27 00:46:38 2019 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uvm_pager.c,v 1.117 2019/12/21 14:41:44 ad Exp $       */
+/*     $NetBSD: uvm_pager.c,v 1.118 2019/12/27 00:46:38 ad Exp $       */
 
 /*
  * Copyright (c) 1997 Charles D. Cranor and Washington University.
@@ -32,7 +32,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uvm_pager.c,v 1.117 2019/12/21 14:41:44 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uvm_pager.c,v 1.118 2019/12/27 00:46:38 ad Exp $");
 
 #include "opt_uvmhist.h"
 #include "opt_readahead.h"
@@ -464,7 +464,6 @@
 
                /* these pages are now only in swap. */
                if (error != ENOMEM) {
-                       KASSERT(uvmexp.swpgonly + npages <= uvmexp.swpginuse);
                        atomic_add_int(&uvmexp.swpgonly, npages);
                }
                if (error) {