[src/trunk]: src/sys/arch/xen/x86 cpu_load_pmap() should not be used to load ...

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

details:   https://anonhg.NetBSD.org/src/rev/dd700c2cfffc
branches:  trunk
changeset: 777558:dd700c2cfffc
user:      cherry <cherry%NetBSD.org@localhost>
date:      Thu Feb 23 04:10:51 2012 +0000

description:
cpu_load_pmap() should not be used to load pmap_kernel(), since in the
x86 model, its mappings are shared across pmaps. KASSERT() for this
and remove unused codepaths.

diffstat:

 sys/arch/xen/x86/cpu.c |  16 ++++++----------
 1 files changed, 6 insertions(+), 10 deletions(-)

diffs (44 lines):

diff -r 70be566ebc32 -r dd700c2cfffc sys/arch/xen/x86/cpu.c
--- a/sys/arch/xen/x86/cpu.c    Thu Feb 23 00:22:07 2012 +0000
+++ b/sys/arch/xen/x86/cpu.c    Thu Feb 23 04:10:51 2012 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: cpu.c,v 1.83 2012/02/22 18:29:31 bouyer Exp $  */
+/*     $NetBSD: cpu.c,v 1.84 2012/02/23 04:10:51 cherry Exp $  */
 /* NetBSD: cpu.c,v 1.18 2004/02/20 17:35:01 yamt Exp  */
 
 /*-
@@ -66,7 +66,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.83 2012/02/22 18:29:31 bouyer Exp $");
+__KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.84 2012/02/23 04:10:51 cherry Exp $");
 
 #include "opt_ddb.h"
 #include "opt_multiprocessor.h"
@@ -1176,6 +1176,8 @@
 void
 cpu_load_pmap(struct pmap *pmap, struct pmap *oldpmap)
 {
+       KASSERT(pmap != pmap_kernel());
+       
 #if defined(__x86_64__) || defined(PAE)
        struct cpu_info *ci = curcpu();
        uint32_t cpumask = ci->ci_cpumask;
@@ -1226,14 +1228,8 @@
                        }
                }
 
-               if (__predict_true(pmap != pmap_kernel())) {
-                       xen_set_user_pgd(pmap_pdirpa(pmap, 0));
-                       ci->ci_xen_current_user_pgd = pmap_pdirpa(pmap, 0);
-               }
-               else {
-                       xpq_queue_pt_switch(l4_pd_ma);
-                       ci->ci_xen_current_user_pgd = 0;
-               }
+               xen_set_user_pgd(pmap_pdirpa(pmap, 0));
+               ci->ci_xen_current_user_pgd = pmap_pdirpa(pmap, 0);
 
                tlbflush();
        }