[src/trunk]: src/sys/arch/x86/x86 - (ab)use pserialize instead of home-grown one

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

details:   https://anonhg.NetBSD.org/src/rev/52dda1fa3fea
branches:  trunk
changeset: 770316:52dda1fa3fea
user:      yamt <yamt%NetBSD.org@localhost>
date:      Wed Oct 12 00:07:29 2011 +0000

description:
- (ab)use pserialize instead of home-grown one
- add an explicit membar

diffstat:

 sys/arch/x86/x86/nmi.c |  29 +++++++++++++++++------------
 1 files changed, 17 insertions(+), 12 deletions(-)

diffs (80 lines):

diff -r d68fa05af226 -r 52dda1fa3fea sys/arch/x86/x86/nmi.c
--- a/sys/arch/x86/x86/nmi.c    Wed Oct 12 00:03:47 2011 +0000
+++ b/sys/arch/x86/x86/nmi.c    Wed Oct 12 00:07:29 2011 +0000
@@ -1,7 +1,7 @@
-/*     $Id: nmi.c,v 1.2 2009/02/24 10:37:27 yamt Exp $ */
+/*     $Id: nmi.c,v 1.3 2011/10/12 00:07:29 yamt Exp $ */
 
 /*-
- * Copyright (c)2009 YAMAMOTO Takashi,
+ * Copyright (c)2009,2011 YAMAMOTO Takashi,
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: nmi.c,v 1.2 2009/02/24 10:37:27 yamt Exp $");
+__KERNEL_RCSID(0, "$NetBSD: nmi.c,v 1.3 2011/10/12 00:07:29 yamt Exp $");
 
 /*
  * nmi dispatcher.
@@ -46,7 +46,7 @@
 #include <sys/atomic.h>
 #include <sys/kmem.h>
 #include <sys/mutex.h>
-#include <sys/xcall.h>
+#include <sys/pserialize.h>
 
 #include <x86/nmi.h>
 
@@ -57,6 +57,7 @@
 };
 
 static kmutex_t nmi_list_lock; /* serialize establish and disestablish */
+static pserialize_t nmi_psz;
 static nmi_handler_t *nmi_handlers; /* list of handlers */
 
 /*
@@ -131,13 +132,7 @@
         * in the middle of nmi_dispatch.
         */
 
-       if (mp_online) {
-               uint64_t h;
-
-               h = xc_broadcast(0, (xcfunc_t)nullop, NULL, NULL);
-               xc_wait(h);
-       }
-
+       pserialize_perform(nmi_psz);
        kmem_free(n, sizeof(*n));
 }
 
@@ -153,9 +148,18 @@
        const struct nmi_handler *n;
        int handled = 0;
 
+       /*
+        * XXX abstraction violation
+        *
+        * we don't bother to call pserialize_read_enter/pserialize_read_exit
+        * because they are not necessary here as we are sure our IPL is
+        * higher than IPL_SOFTCLOCK.  better to avoid unnecessary calls as
+        * we are in a dangerous context. (NMI)
+        */
+
        for (n = nmi_handlers; /* atomic load */
            n != NULL;
-           n = n->n_next) { /* atomic load */
+           membar_consumer(), n = n->n_next) { /* atomic load */
                handled |= (*n->n_func)(tf, n->n_arg);
        }
        return handled;
@@ -166,4 +170,5 @@
 {
 
        mutex_init(&nmi_list_lock, MUTEX_DEFAULT, IPL_NONE);
+       nmi_psz = pserialize_create();
 }