[src/trunk]: src/sys/arch/alpha/alpha - Revert previous, and do debugger entr...

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

details:   https://anonhg.NetBSD.org/src/rev/27553949a8cf
branches:  trunk
changeset: 472091:27553949a8cf
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Tue Apr 20 21:16:59 1999 +0000

description:
- Revert previous, and do debugger entry if kernel BUGCHK or BPT traps
  happen.  If the debugger doesn't handle the trap, arrange things so the
  debugger won't be called again before we panic.
- Before panic'ing, give the debugger a chance to field the trap, and
  if the debugger has handled things, allow the kernel to continue running,
  like the i386 port does.

diffstat:

 sys/arch/alpha/alpha/trap.c |  46 +++++++++++++++++++++++++++-----------------
 1 files changed, 28 insertions(+), 18 deletions(-)

diffs (82 lines):

diff -r ba083e081442 -r 27553949a8cf sys/arch/alpha/alpha/trap.c
--- a/sys/arch/alpha/alpha/trap.c       Tue Apr 20 21:11:59 1999 +0000
+++ b/sys/arch/alpha/alpha/trap.c       Tue Apr 20 21:16:59 1999 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: trap.c,v 1.43 1999/04/19 23:24:14 thorpej Exp $ */
+/* $NetBSD: trap.c,v 1.44 1999/04/20 21:16:59 thorpej Exp $ */
 
 /*
  * Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University.
@@ -34,7 +34,7 @@
 
 #include <sys/cdefs.h>                 /* RCS ID & Copyright macro defns */
 
-__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.43 1999/04/19 23:24:14 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.44 1999/04/20 21:16:59 thorpej Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -216,6 +216,9 @@
        u_int64_t ucode;
        u_quad_t sticks;
        int user;
+#if defined(DDB)
+       int call_debugger = 1;
+#endif
 
        uvmexp.traps++;
        p = curproc;
@@ -284,8 +287,23 @@
                 * These are always fatal in kernel, and should never
                 * happen.  (Debugger entry is handled in XentIF.)
                 */
-               if (!user)
+               if (!user) {
+#if defined(DDB)
+                       /*
+                        * ...unless a debugger is configured.  It will
+                        * inform us if the trap was handled.
+                        */
+                       if (alpha_debug(a0, a1, a2, entry, framep))
+                               goto out;
+
+                       /*
+                        * Debugger did NOT handle the trap, don't
+                        * call the debugger again!
+                        */
+                       call_debugger = 0;
+#endif
                        goto dopanic;
+               }
                i = 0;
                switch (a0) {
                case ALPHA_IF_CODE_GENTRAP:
@@ -475,21 +493,13 @@
 
        /* XXX dump registers */
 
-#ifdef DDB
-       /* XXX
-        * Really would like to be able to indicate that the
-        * kernel should _not_ panic, here.  However, two problems
-        * exist:
-        *
-        *      (a) There is not currently a way for DDB to distinguish
-        *          between "continue and panic" and "continue, and
-        *          don't panic".
-        *
-        *      (b) panic() will again invoke the debugger, so calling
-        *          it here is silly.
-        *
-        * For now, we just do nothing.
-        */
+#if defined(DDB)
+       if (call_debugger && alpha_debug(a0, a1, a2, entry, framep)) {
+               /*
+                * The debugger has handled the trap; just return.
+                */
+               goto out;
+       }
 #endif
 
        panic("trap");