[src/trunk]: src/sys/arch/i386/i386 Improve readability of trap() by extracti...

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

details:   https://anonhg.NetBSD.org/src/rev/e4d358060ec7
branches:  trunk
changeset: 747915:e4d358060ec7
user:      dyoung <dyoung%NetBSD.org@localhost>
date:      Mon Oct 05 19:04:14 2009 +0000

description:
Improve readability of trap() by extracting two subroutines,
trap_print() and check_dr0().

diffstat:

 sys/arch/i386/i386/trap.c |  60 ++++++++++++++++++++++++++++------------------
 1 files changed, 36 insertions(+), 24 deletions(-)

diffs (89 lines):

diff -r 2e023897cc55 -r e4d358060ec7 sys/arch/i386/i386/trap.c
--- a/sys/arch/i386/i386/trap.c Mon Oct 05 17:58:15 2009 +0000
+++ b/sys/arch/i386/i386/trap.c Mon Oct 05 19:04:14 2009 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: trap.c,v 1.247 2009/07/29 18:47:15 rmind Exp $ */
+/*     $NetBSD: trap.c,v 1.248 2009/10/05 19:04:14 dyoung Exp $        */
 
 /*-
  * Copyright (c) 1998, 2000, 2005, 2006, 2007, 2008 The NetBSD Foundation, Inc.
@@ -68,7 +68,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.247 2009/07/29 18:47:15 rmind Exp $");
+__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.248 2009/10/05 19:04:14 dyoung Exp $");
 
 #include "opt_ddb.h"
 #include "opt_kgdb.h"
@@ -252,6 +252,37 @@
        return NULL;
 }
 
+static void
+trap_print(int type, struct trapframe *frame)
+{
+       if (frame->tf_trapno < trap_types)
+               printf("fatal %s", trap_type[frame->tf_trapno]);
+       else
+               printf("unknown trap %d", frame->tf_trapno);
+       printf(" in %s mode\n", (type & T_USER) ? "user" : "supervisor");
+       printf("trap type %d code %x eip %x cs %x eflags %x cr2 %lx ilevel %x\n",
+           type, frame->tf_err, frame->tf_eip, frame->tf_cs,
+           frame->tf_eflags, (long)rcr2(), curcpu()->ci_ilevel);
+}
+
+static void
+check_dr0(void)
+{
+#ifdef KSTACK_CHECK_DR0
+       u_int mask, dr6 = rdr6();
+
+       mask = 1 << 0; /* dr0 */
+       if (dr6 & mask) {
+               panic("trap on DR0: maybe kernel stack overflow\n");
+#if 0
+               dr6 &= ~mask;
+               ldr6(dr6);
+               return;
+#endif
+       }
+#endif
+}
+
 /*
  * trap(frame): exception, fault, and trap interface to BSD kernel.
  *
@@ -314,29 +345,10 @@
 
        default:
        we_re_toast:
-#ifdef KSTACK_CHECK_DR0
-               if (type == T_TRCTRAP) {
-                       u_int mask, dr6 = rdr6();
-
-                       mask = 1 << 0; /* dr0 */
-                       if (dr6 & mask) {
-                               panic("trap on DR0: maybe kernel stack overflow\n");
-#if 0
-                               dr6 &= ~mask;
-                               ldr6(dr6);
-                               return;
-#endif
-                       }
-               }
-#endif
-               if (frame->tf_trapno < trap_types)
-                       printf("fatal %s", trap_type[frame->tf_trapno]);
+               if (type == T_TRCTRAP)
+                       check_dr0();
                else
-                       printf("unknown trap %d", frame->tf_trapno);
-               printf(" in %s mode\n", (type & T_USER) ? "user" : "supervisor");
-               printf("trap type %d code %x eip %x cs %x eflags %x cr2 %lx ilevel %x\n",
-                   type, frame->tf_err, frame->tf_eip, frame->tf_cs,
-                   frame->tf_eflags, (long)rcr2(), curcpu()->ci_ilevel);
+                       trap_print(type, frame);
 #ifdef DDB
                if (kdb_trap(type, 0, frame))
                        return;