2006-10-12 Martin Hunt <hunt@redhat.com>

	* stack.c: Reorganize and split arch-specific functions to
	separate files.
	(_stp_kta): Better checking.
	(_stp_stack_sprint): Better handling of return probes.

	* stack-i386.c: New file. Uses 2.6.18 DWARF unwinder if available.
	* stack-x86_64.c: New file. Uses 2.6.18 DWARF unwinder if available.
	* stack-ppc64.c: New file.
	* stack-ia64.c: New file.

	* sym.c (_stp_kallsyms_lookup_name): New function. Like
	kallsyms_lookup_name() except use our internal lookup table.

1 files changed, 102 insertions, 0 deletions

diff --git a/runtime/stack-i386.c b/runtime/stack-i386.c
new file mode 100644
index 00000000..d36f30d2
--- /dev/null
+++ b/runtime/stack-i386.c
@@ -0,0 +1,102 @@
+/* -*- linux-c -*-
+ * i386 stack tracing functions
+ * Copyright (C) 2005, 2006 Red Hat Inc.
+ *
+ * This file is part of systemtap, and is free software.  You can
+ * redistribute it and/or modify it under the terms of the GNU General
+ * Public License (GPL); either version 2, or (at your option) any
+ * later version.
+ */
+#ifdef CONFIG_STACK_UNWIND
+#include <linux/unwind.h>
+
+static inline int _stp_valid_stack_ptr_info(struct unwind_frame_info *info)
+{
+	unsigned long context = (unsigned long)UNW_SP(info) & ~(THREAD_SIZE - 1);
+	unsigned long p = UNW_PC(info);
+	return	p > context && p < context + THREAD_SIZE - 3;
+}
+
+static int
+_stp_show_trace_unwind(String str, struct unwind_frame_info *info, int verbose)
+{
+	int n = 0;
+
+	while (unwind(info) == 0 && UNW_PC(info)) {
+		if (_stp_valid_stack_ptr_info(info))
+			break;
+		n++;
+		if (verbose) {
+			_stp_string_cat(str, " ");
+			_stp_symbol_sprint (str, UNW_PC(info));
+			_stp_string_cat(str, "\n");
+		} else
+			_stp_sprintf (str, "%p ", UNW_PC(info));
+		if (arch_unw_user_mode(info))
+			break;
+	}
+	return n;
+}
+#endif /* CONFIG_STACK_UNWIND */
+
+static inline int _stp_valid_stack_ptr(unsigned long context, unsigned long p)
+{
+	return	p > context && p < context + THREAD_SIZE - 3;
+}
+
+static void __stp_stack_sprint (String str, struct pt_regs *regs, int verbose, int levels)
+{
+	unsigned long *stack = (unsigned long *)&REG_SP(regs);
+	unsigned long context = (unsigned long)stack & ~(THREAD_SIZE - 1);
+	unsigned long addr;
+	int uw_ret = 0;
+
+#ifdef CONFIG_STACK_UNWIND
+	struct unwind_frame_info info;
+	if (unwind_init_frame_info(&info, current, regs) == 0)
+		uw_ret = _stp_show_trace_unwind(str, &info, verbose);
+	stack = (void *)UNW_SP(&info);
+#endif
+
+	if (uw_ret == 0)
+		_stp_string_cat(str, "Inexact backtrace:\n");
+
+#ifdef	CONFIG_FRAME_POINTER
+	{
+		unsigned long ebp;
+		/* Grab ebp right from our regs.*/
+		asm ("movl %%ebp, %0" : "=r" (ebp) : );
+		
+		while (_stp_valid_stack_ptr(context, (unsigned long)ebp)) {
+			addr = *(unsigned long *)(ebp + 4);
+			if (verbose) {
+				if (uw_ret) {
+					uw_ret = 0;
+					_stp_string_cat(str, "Leftover inexact backtrace:\n");
+				}
+				_stp_string_cat(str, " ");
+				_stp_symbol_sprint (str, addr);
+				_stp_string_cat(str, "\n");
+			} else
+				_stp_sprintf (str, "%p ", (void *)addr);
+			ebp = *(unsigned long *)ebp;
+		}
+	}
+#else
+	while (_stp_valid_stack_ptr(context, (unsigned long)stack)) {
+		addr = *stack++;
+		if (_stp_kta(addr)) {
+			if (verbose) {
+				if (uw_ret) {
+					uw_ret = 0;
+					_stp_string_cat(str, "Leftover inexact backtrace:\n");
+				}
+				_stp_string_cat(str, " ");
+				_stp_symbol_sprint(str, addr);
+				_stp_string_cat(str, "\n");
+			} else
+				_stp_sprintf (str, "%p ", (void *)addr);
+		}
+	}
+#endif
+}