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.

7 files changed, 378 insertions, 199 deletions

diff --git a/runtime/ChangeLog b/runtime/ChangeLog
index 6871025f..66519fa8 100644
--- a/runtime/ChangeLog
+++ b/runtime/ChangeLog
@@ -1,3 +1,18 @@
+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.
+
 2006-10-10  Frank Ch. Eigler  <fche@elastic.org>
 
 	* runtime/lket/b2a/lket_b2a.c: Add several missing #ifdef HAS_MYSQL.
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
+}
diff --git a/runtime/stack-ia64.c b/runtime/stack-ia64.c
new file mode 100644
index 00000000..f941869e
--- /dev/null
+++ b/runtime/stack-ia64.c
@@ -0,0 +1,65 @@
+/* -*- linux-c -*-
+ * ia64 stack tracing functions
+ * Copyright (C) 2005 Intel Corporation.
+ *
+ * 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.
+ */
+
+struct dump_para{
+	unsigned long *sp;
+	String str;
+};
+
+static void __stp_show_stack_sym(struct unw_frame_info *info, void *arg)
+{
+	unsigned long ip, skip=1;
+	String str = ((struct dump_para*)arg)->str;
+	struct pt_regs *regs = container_of(((struct dump_para*)arg)->sp, struct pt_regs, r12);
+
+	do {
+		unw_get_ip(info, &ip);
+		if (ip == 0) break;
+                if (skip){
+			if (ip == REG_IP(regs))
+				skip = 0;
+                        else continue;
+                }
+		_stp_string_cat(str, " ");
+		_stp_symbol_sprint(str, ip);
+		_stp_string_cat (str, "\n");
+        } while (unw_unwind(info) >= 0);
+}
+
+static void __stp_show_stack_addr(struct unw_frame_info *info, void *arg)
+{
+	unsigned long ip, skip=1;
+	String str = ((struct dump_para*)arg)->str;
+	struct pt_regs *regs = container_of(((struct dump_para*)arg)->sp, struct pt_regs, r12);	
+
+	do {
+		unw_get_ip(info, &ip);
+		if (ip == 0) break;
+		if (skip){
+			if (ip == REG_IP(regs))
+				skip = 0;
+			continue;
+		}
+		_stp_sprintf (str, "%lx ", ip);
+	} while (unw_unwind(info) >= 0);
+}
+
+static void __stp_stack_sprint (String str, struct pt_regs *regs, int verbose, int levels)
+{
+	unsigned long *stack = (unsigned long *)&REG_SP(regs);
+	struct dump_para para;
+	
+	para.str = str;
+	para.sp  = stack; 
+	if (verbose)
+		unw_init_running(__stp_show_stack_sym, &para);
+        else
+		unw_init_running(__stp_show_stack_addr, &para);
+}
diff --git a/runtime/stack-ppc64.c b/runtime/stack-ppc64.c
new file mode 100644
index 00000000..0a30bc84
--- /dev/null
+++ b/runtime/stack-ppc64.c
@@ -0,0 +1,62 @@
+/* -*- linux-c -*-
+ * ppc64 stack tracing functions
+ *
+ * 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.
+ */
+
+static void __stp_stack_sprint (String str, struct pt_regs *regs, int verbose, int levels)
+{
+	unsigned long ip, newsp, lr = 0;
+	int count = 0;
+	unsigned long sp = (unsigned long)_sp;
+	int firstframe = 1;
+	unsigned long *_sp = (unsigned long *)&REG_SP(regs);	
+	lr = 0;
+	do {
+		if (sp < KERNELBASE)
+			return;
+		_sp = (unsigned long *) sp;
+		newsp = _sp[0];
+		ip = _sp[2];
+		if (!firstframe || ip != lr) {
+			if (verbose) {
+				_stp_sprintf(str, "[%016lx] [%016lx] ", sp, ip);
+				_stp_symbol_sprint(str, ip);
+				if (firstframe)
+					_stp_string_cat(str, " (unreliable)");
+				_stp_string_cat(str, "\n");
+			}
+			else
+				_stp_sprintf(str,"%lx ", ip);
+		}
+		firstframe = 0;
+		/*
+		 * See if this is an exception frame.
+		 * We look for the "regshere" marker in the current frame.
+		 */
+		if ( _sp[12] == 0x7265677368657265ul) {
+			struct pt_regs *regs = (struct pt_regs *)
+				(sp + STACK_FRAME_OVERHEAD);
+			if (verbose) {
+				_stp_sprintf(str, "--- Exception: %lx at ",
+						regs->trap);
+				_stp_symbol_sprint(str, regs->nip);
+				_stp_string_cat(str, "\n");
+				lr = regs->link;
+				_stp_string_cat(str, "    LR =");
+				_stp_symbol_sprint(str, lr);
+				_stp_string_cat(str, "\n");
+				firstframe = 1;
+			}
+			else {
+				_stp_sprintf(str, "%lx ",regs->nip);
+				_stp_sprintf(str, "%lx ",regs->link);
+			}
+		}
+
+		sp = newsp;
+	} while (str->len < STP_STRING_SIZE);
+}
diff --git a/runtime/stack-x86_64.c b/runtime/stack-x86_64.c
new file mode 100644
index 00000000..3a188c2c
--- /dev/null
+++ b/runtime/stack-x86_64.c
@@ -0,0 +1,72 @@
+/* -*- linux-c -*-
+ * x86_64 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(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))
+			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 void __stp_stack_sprint (String str, struct pt_regs *regs, int verbose, int levels)
+{
+	unsigned long *stack = (unsigned long *)&REG_SP(regs);
+	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");
+
+	while ((long)stack & (THREAD_SIZE-1)) {
+		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);
+		}
+	}
+}
diff --git a/runtime/stack.c b/runtime/stack.c
index 7037fa8f..dbbac9ac 100644
--- a/runtime/stack.c
+++ b/runtime/stack.c
@@ -1,5 +1,6 @@
-/* Stack tracing functions
- * Copyright (C) 2005 Red Hat Inc.
+/*  -*- linux-c -*-
+ * Stack tracing functions
+ * Copyright (C) 2005, 2006 Red Hat Inc.
  * Copyright (C) 2005 Intel Corporation.
  *
  * This file is part of systemtap, and is free software.  You can
@@ -8,7 +9,7 @@
  * later version.
  */
 
-#ifndef _STACK_C_ /* -*- linux-c -*- */
+#ifndef _STACK_C_
 #define _STACK_C_
 
 
@@ -29,222 +30,65 @@
 
 #include "sym.c"
 #include "regs.h"
-
-static int _stp_kta(unsigned long addr)
-{
-	if (addr >= stap_symbols[0].addr && 
-	    addr <= stap_symbols[stap_num_symbols-1].addr)
-		return 1;
-	return 0;
-}
+static int _stp_kta(unsigned long addr);
 
 #if defined (__x86_64__)
-
-static void __stp_stack_sprint (String str, unsigned long *stack, int verbose, int levels)
-{
-	unsigned long addr;
-	while (((long) stack & (THREAD_SIZE-1)) != 0) {
-		addr = *stack++;
-		if (_stp_kta(addr)) {
-			if (verbose) {
-				_stp_string_cat(str, " ");
-				_stp_symbol_sprint (str, addr);
-				_stp_string_cat (str, "\n");
-			} else 
-				_stp_sprintf (str, "%lx ", addr);
-		}
-	}
-}
-
+#include "stack-x86_64.c"
 #elif defined (__ia64__)
-struct dump_para{
-  unsigned long *sp;
-  String str;
-};
-
-static void __stp_show_stack_sym(struct unw_frame_info *info, void *arg)
-{
-   unsigned long ip, skip=1;
-   String str = ((struct dump_para*)arg)->str;
-   struct pt_regs *regs = container_of(((struct dump_para*)arg)->sp, struct pt_regs, r12);
-
-	do {
-		unw_get_ip(info, &ip);
-		if (ip == 0) break;
-                if (skip){
-			if (ip == REG_IP(regs))
-				skip = 0;
-                        else continue;
-                }
-		_stp_string_cat(str, " ");
-		_stp_symbol_sprint(str, ip);
-		_stp_string_cat (str, "\n");
-        } while (unw_unwind(info) >= 0);
-}
-
-static void __stp_show_stack_addr(struct unw_frame_info *info, void *arg)
-{
-   unsigned long ip, skip=1;
-   String str = ((struct dump_para*)arg)->str;
-   struct pt_regs *regs = container_of(((struct dump_para*)arg)->sp, struct pt_regs, r12);	
-
-	do {
-		unw_get_ip(info, &ip);
-		if (ip == 0) break;
-		if (skip){
-			if (ip == REG_IP(regs))
-				skip = 0;
-			continue;
-		}
-		_stp_sprintf (str, "%lx ", ip);
-	} while (unw_unwind(info) >= 0);
-}
-
-static void __stp_stack_sprint (String str, unsigned long *stack, int verbose, int levels)
-{
-  struct dump_para para;
-
-	para.str = str;
-	para.sp  = stack; 
-	if (verbose)
-	    unw_init_running(__stp_show_stack_sym, &para);
-        else
-	    unw_init_running(__stp_show_stack_addr, &para);
-}
-
+#include "stack-ia64.c"
 #elif  defined (__i386__)
-
-static inline int valid_stack_ptr(struct thread_info *tinfo, void *p)
-{
-	return	p > (void *)tinfo &&
-		p < (void *)tinfo + THREAD_SIZE - 3;
-}
-
-static inline unsigned long print_context_stack(String str, struct thread_info *tinfo,
-						unsigned long *stack, unsigned long ebp, int verbose)
-{
-	unsigned long addr;
-
-#ifdef	CONFIG_FRAME_POINTER
-	while (valid_stack_ptr(tinfo, (void *)ebp)) {
-		addr = *(unsigned long *)(ebp + 4);
-		if (verbose) {
-			_stp_string_cat(str, " ");
-			_stp_symbol_sprint (str, addr);
-			_stp_string_cat(str, "\n");
-		} else
-			_stp_sprintf (str, "%lx ", addr);
-		ebp = *(unsigned long *)ebp;
-	}
+#include "stack-i386.c"
+#elif defined (__powerpc64__)
+#include "stack-ppc64.c"
 #else
-	while (valid_stack_ptr(tinfo, stack)) {
-		addr = *stack++;
-		if (_stp_kta(addr)) {
-			if (verbose) {
-				_stp_string_cat(str, " ");
-				_stp_symbol_sprint(str, addr);
-				_stp_string_cat(str, "\n");
-			} else
-				_stp_sprintf (str, "%lx ", addr);
-		}
-	}
+#error "Unsupported architecture"
 #endif
-	return ebp;
-}
 
-static void __stp_stack_sprint (String str, unsigned long *stack, int verbose, int levels)
-{
-	unsigned long ebp;
-
-	/* Grab ebp right from our regs */
-	asm ("movl %%ebp, %0" : "=r" (ebp) : );
 
-	while (1) {
-		struct thread_info *context;
-		context = (struct thread_info *)
-			((unsigned long)stack & (~(THREAD_SIZE - 1)));
-		ebp = print_context_stack(str, context, stack, ebp, verbose);
-		stack = (unsigned long*)context->previous_esp;
-		if (!stack)
-			break;
+/* our copy of kernel_text_address() */
+static int _stp_kta(unsigned long addr)
+{
+	static unsigned long stext, etext, sinittext, einittext;
+	static int init = 0;
+	
+	if (init == 0) {
+		init = 1;
+		etext = _stp_kallsyms_lookup_name("_etext");
+		stext = _stp_kallsyms_lookup_name("_stext");
+		sinittext = _stp_kallsyms_lookup_name("_sinittext");
+		einittext = _stp_kallsyms_lookup_name("_einittext");
 	}
-}
-#elif defined (__powerpc64__)
 
-static void __stp_stack_sprint (String str, unsigned long *_sp,
-				int verbose, int levels)
-{
-	unsigned long ip, newsp, lr = 0;
-	int count = 0;
-	unsigned long sp = (unsigned long)_sp;
-	int firstframe = 1;
+	if (addr >= stext && addr <= etext)
+		return 1;
 
-	lr = 0;
-	do {
-		if (sp < KERNELBASE)
-			return;
-		_sp = (unsigned long *) sp;
-		newsp = _sp[0];
-		ip = _sp[2];
-		if (!firstframe || ip != lr) {
-			if (verbose) {
-				_stp_sprintf(str, "[%016lx] [%016lx] ", sp, ip);
-				_stp_symbol_sprint(str, ip);
-				if (firstframe)
-					_stp_string_cat(str, " (unreliable)");
-			}
-			else
-				_stp_sprintf(str,"%lx ", ip);
-		}
-		firstframe = 0;
-		/*
-		 * See if this is an exception frame.
-		 * We look for the "regshere" marker in the current frame.
-		 */
-		if ( _sp[12] == 0x7265677368657265ul) {
-			struct pt_regs *regs = (struct pt_regs *)
-				(sp + STACK_FRAME_OVERHEAD);
-			if (verbose) {
-				_stp_sprintf(str, "--- Exception: %lx at ",
-						regs->trap);
-				_stp_symbol_sprint(str, regs->nip);
-				_stp_string_cat(str, "\n");
-				lr = regs->link;
-				_stp_string_cat(str, "    LR =");
-				_stp_symbol_sprint(str, lr);
-				_stp_string_cat(str, "\n");
-				firstframe = 1;
-			}
-			else {
-				_stp_sprintf(str, "%lx ",regs->nip);
-				_stp_sprintf(str, "%lx ",regs->link);
-			}
-		}
+	if (addr >= sinittext && addr <= einittext)
+		return 1;
 
-		sp = newsp;
-	} while (str->len < STP_STRING_SIZE);
+	return 0;
 }
 
-#else
-#error "Unsupported architecture"
-#endif
-
-
 /** Writes stack backtrace to a String
  *
  * @param str String
  * @param regs A pointer to the struct pt_regs.
  * @returns Same String as was input with trace info appended,
  */
-String _stp_stack_sprint (String str, struct pt_regs *regs, int verbose)
+String _stp_stack_sprint (String str, struct pt_regs *regs, int verbose, struct kretprobe_instance *pi)
 {
 	if (verbose) {
-		_stp_sprintf (str, "trace for %d (%s)\n ", current->pid, current->comm);
-		_stp_symbol_sprint (str, REG_IP(regs));
+		/* print the current address */
+		if (pi) {
+			_stp_string_cat(str, "Returning from: ");
+			_stp_symbol_sprint(str, (unsigned long)_stp_probe_addr_r(pi));
+			_stp_string_cat(str, "\nReturning to: ");
+			_stp_symbol_sprint(str, (unsigned long)_stp_ret_addr_r(pi));
+		} else
+			_stp_symbol_sprint (str, REG_IP(regs));
 		_stp_string_cat(str, "\n");
 	} else
 		_stp_sprintf (str, "%lx ", REG_IP(regs));
-	__stp_stack_sprint (str, (unsigned long *)&REG_SP(regs), verbose, 0);
+	__stp_stack_sprint (str, regs, verbose, 0);
 	return str;
 }
 
@@ -252,7 +96,7 @@ String _stp_stack_sprint (String str, struct pt_regs *regs, int verbose)
  * @param regs A pointer to the struct pt_regs.
  */
 
-#define _stp_stack_print(regs)	(void)_stp_stack_sprint(_stp_stdout,regs,1)
+#define _stp_stack_print(regs,pi)	(void)_stp_stack_sprint(_stp_stdout,regs,1,pi)
 
 /** Writes stack backtrace to a String.
  * Use this when calling from a jprobe.
@@ -264,7 +108,7 @@ String _stp_stack_sprintj(String str)
 {
 	unsigned long stack;
 	_stp_sprintf (str, "trace for %d (%s)\n", current->pid, current->comm);
-	__stp_stack_sprint (str, &stack, 1, 0);
+/*	__stp_stack_sprint (str, &stack, 1, 0); */
 	return str;
 }
 
diff --git a/runtime/sym.c b/runtime/sym.c
index 3843a3a5..c10e89fd 100644
--- a/runtime/sym.c
+++ b/runtime/sym.c
@@ -20,6 +20,25 @@
  * @{
  */
 
+/* Lookup the kernel address for this symbol. Returns 0 if not found. */
+static unsigned long _stp_kallsyms_lookup_name(const char *name)
+{
+	struct stap_symbol *s = &stap_symbols[0];
+	unsigned num = stap_num_symbols;
+
+	/* Warning: Linear search. If this function ends up being used in */
+	/* time-critical places, maybe we need to create a new symbol table */
+	/* sorted by name. */
+
+	while (num--) {
+		if ((strcmp(name, s->symbol) == 0) && (strcmp(s->modname,"") == 0))
+			return s->addr;
+		s++;
+	}
+
+	return 0;
+}
+
 static const char * _stp_kallsyms_lookup (
 	unsigned long addr,
 	unsigned long *symbolsize,
@@ -80,7 +99,7 @@ String _stp_symbol_sprint (String str, unsigned long address)
 
         name = _stp_kallsyms_lookup(address, &size, &offset, &modname, namebuf);
 
-	_stp_sprintf (str, "0x%lx", address);
+	_stp_sprintf (str, "%p", (void *)address);
 
 	if (name) {		
 		if (modname)
@@ -119,13 +138,13 @@ const char *_stp_symbol_sprint_basic (char *str, size_t len, unsigned long addre
     if (len > KSYM_NAME_LEN) {
         name = _stp_kallsyms_lookup(address, &size, &offset, &modname, str);
         if (!name)
-            snprintf(str, len, "0x%lx", address);
+		snprintf(str, len, "%p", (void *)address);
     } else {
         name = _stp_kallsyms_lookup(address, &size, &offset, &modname, namebuf);
         if (name)
             strlcpy(str, namebuf, len);
         else
-            snprintf(str, len, "0x%lx", address);
+		snprintf(str, len, "%p", (void *)address);
     }
 
     return str;