Differentiate between interrupt frames, trap interrupt frames and timer

frame in the kgdb, to allow it to properly backtrace over the interrupt
stacks.

Noted and reviewed by:	tegge
Tested by:	pho
MFC after:	1 week

1 files changed, 33 insertions, 3 deletions

diff --git a/gnu/usr.bin/gdb/kgdb/trgt_i386.c b/gnu/usr.bin/gdb/kgdb/trgt_i386.c
index 879caea..4a66906 100644
--- a/gnu/usr.bin/gdb/kgdb/trgt_i386.c
+++ b/gnu/usr.bin/gdb/kgdb/trgt_i386.c
@@ -242,10 +242,14 @@ static const struct frame_unwind kgdb_trgt_dblfault_unwind = {
 };
 
 struct kgdb_frame_cache {
-	int		intrframe;
+	int		frame_type;
 	CORE_ADDR	pc;
 	CORE_ADDR	sp;
 };
+#define	FT_NORMAL		1
+#define	FT_INTRFRAME		2
+#define	FT_INTRTRAPFRAME	3
+#define	FT_TIMERFRAME		4
 
 static int kgdb_trgt_frame_offset[15] = {
 	offsetof(struct trapframe, tf_eax),
@@ -278,7 +282,17 @@ kgdb_trgt_frame_cache(struct frame_info *next_frame, void **this_cache)
 		*this_cache = cache;
 		cache->pc = frame_func_unwind(next_frame);
 		find_pc_partial_function(cache->pc, &pname, NULL, NULL);
-		cache->intrframe = (pname[0] == 'X') ? 1 : 0;
+		if (pname[0] != 'X')
+			cache->frame_type = FT_NORMAL;
+		else if (strcmp(pname, "Xtimerint") == 0)
+			cache->frame_type = FT_TIMERFRAME;
+		else if (strcmp(pname, "Xcpustop") == 0 ||
+		    strcmp(pname, "Xrendezvous") == 0 ||
+		    strcmp(pname, "Xipi_intr_bitmap_handler") == 0 ||
+		    strcmp(pname, "Xlazypmap") == 0)
+			cache->frame_type = FT_INTRTRAPFRAME;
+		else
+			cache->frame_type = FT_INTRFRAME;
 		frame_unwind_register(next_frame, SP_REGNUM, buf);
 		cache->sp = extract_unsigned_integer(buf,
 		    register_size(current_gdbarch, SP_REGNUM));
@@ -321,7 +335,23 @@ kgdb_trgt_trapframe_prev_register(struct frame_info *next_frame,
 		return;
 
 	cache = kgdb_trgt_frame_cache(next_frame, this_cache);
-	*addrp = cache->sp + ofs + (cache->intrframe ? 4 : 0);
+	switch (cache->frame_type) {
+	case FT_NORMAL:
+		break;
+	case FT_INTRFRAME:
+		ofs += 4;
+		break;
+	case FT_TIMERFRAME:
+		break;
+	case FT_INTRTRAPFRAME:
+		ofs -= ofs_fix;
+		break;
+	default:
+		fprintf_unfiltered(gdb_stderr, "Correct FT_XXX frame offsets "
+		   "for %d\n", cache->frame_type);
+		break;
+	}
+	*addrp = cache->sp + ofs;
 	*lvalp = lval_memory;
 	target_read_memory(*addrp, valuep, regsz);
 }