Pass task from tapset, through stack and unwind functions for lookup.

* runtime/stack-arm.c (__stp_stack_print): Take struct task_struct *.
* runtime/stack-ia64.c (__stp_stack_print): Likewise.
* runtime/stack-ppc64.c (__stp_stack_print): Likewise.
* runtime/stack-s390.c (__stp_stack_print): Likewise.
* runtime/stack-i386.c (__stp_stack_print): Likewise.
  And add check and pass to unwind() and _stp_func_print().
* runtime/stack-x86_64.c: Likewise.
* runtime/stack.c *_stp_stack_print): Take and pass on task_struct.
  (_stp_stack_snprint): Likewise.
* runtime/unwind.c (unwind): Take and use task_struct for
  _stp_mod_sec_lookup().
* tapset/context-unwind.stp (print_backtrace): Pass NULL to
  _stp_stack_print().
  (backtrace): Pass NULL to _stp_stack_snprint().

8 files changed, 25 insertions, 19 deletions

diff --git a/runtime/stack-arm.c b/runtime/stack-arm.c
index 9b0b772d..fcff0a3b 100644
--- a/runtime/stack-arm.c
+++ b/runtime/stack-arm.c
@@ -31,7 +31,8 @@ static int __init find_str_pc_offset(void)
 }
 
 
-static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels)
+static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels,
+                               struct task_struct *tsk)
 {
 #ifdef STP_USE_FRAME_POINTER
 	int		pc_offset = find_str_pc_offset();
diff --git a/runtime/stack-i386.c b/runtime/stack-i386.c
index a37ddd72..6fd1613f 100644
--- a/runtime/stack-i386.c
+++ b/runtime/stack-i386.c
@@ -30,7 +30,8 @@ static void _stp_stack_print_fallback(unsigned long stack, int verbose, int leve
 }
 #endif
 
-static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels)
+static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels,
+                               struct task_struct *tsk)
 {
 	unsigned long context = (unsigned long)&REG_SP(regs) & ~(THREAD_SIZE - 1);
 
@@ -60,11 +61,11 @@ static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels)
 	struct unwind_frame_info info;
 	arch_unw_init_frame_info(&info, regs);
 
-	while (levels && !arch_unw_user_mode(&info)) {
-		int ret = unwind(&info);
+	while (levels && (tsk || !arch_unw_user_mode(&info))) {
+		int ret = unwind(&info, tsk);
 		dbug_unwind(1, "ret=%d PC=%lx SP=%lx\n", ret, UNW_PC(&info), UNW_SP(&info));
 		if (ret == 0) {
-			_stp_func_print(UNW_PC(&info), verbose, 1, current);
+			_stp_func_print(UNW_PC(&info), verbose, 1, tsk);
 			levels--;
 			continue;
 		}
diff --git a/runtime/stack-ia64.c b/runtime/stack-ia64.c
index ca9d25a6..a04355fa 100644
--- a/runtime/stack-ia64.c
+++ b/runtime/stack-ia64.c
@@ -48,7 +48,8 @@ static void __stp_show_stack_addr(struct unw_frame_info *info, void *arg)
 	} while (unw_unwind(info) >= 0);
 }
 
-static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels)
+static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels,
+                               struct task_struct *tsk)
 {
 	unsigned long *stack = (unsigned long *)&REG_SP(regs);
 	struct dump_para para;
diff --git a/runtime/stack-ppc64.c b/runtime/stack-ppc64.c
index 3dc38526..3267194e 100644
--- a/runtime/stack-ppc64.c
+++ b/runtime/stack-ppc64.c
@@ -7,7 +7,8 @@
  * later version.
  */
 
-static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels)
+static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels,
+                               struct task_struct *tsk)
 {
 	unsigned long ip, newsp, lr = 0;
 	int count = 0;
diff --git a/runtime/stack-s390.c b/runtime/stack-s390.c
index c9654102..14e9b7d8 100644
--- a/runtime/stack-s390.c
+++ b/runtime/stack-s390.c
@@ -66,7 +66,8 @@ __stp_show_stack (unsigned long sp, unsigned long low,
 }
  
 static void __stp_stack_print (struct pt_regs *regs,
-			       int verbose, int levels)
+			       int verbose, int levels,
+	                       struct task_struct *tsk)
 {
 		unsigned long *_sp = (unsigned long *)&REG_SP(regs);
 		unsigned long sp = (unsigned long)_sp;
diff --git a/runtime/stack-x86_64.c b/runtime/stack-x86_64.c
index 33928677..03eb33e8 100644
--- a/runtime/stack-x86_64.c
+++ b/runtime/stack-x86_64.c
@@ -27,18 +27,19 @@ static void _stp_stack_print_fallback(unsigned long stack, int verbose, int leve
 #endif
 
 
-static void __stp_stack_print(struct pt_regs *regs, int verbose, int levels)
+static void __stp_stack_print(struct pt_regs *regs, int verbose, int levels,
+                              struct task_struct *tsk)
 {
 #ifdef STP_USE_DWARF_UNWINDER
 	// FIXME: large stack allocation
 	struct unwind_frame_info info;
 	arch_unw_init_frame_info(&info, regs);
 
-	while (levels && !arch_unw_user_mode(&info)) {
-		int ret = unwind(&info);
+	while (levels && (tsk || !arch_unw_user_mode(&info))) {
+		int ret = unwind(&info, tsk);
 		dbug_unwind(1, "ret=%d PC=%lx SP=%lx\n", ret, UNW_PC(&info), UNW_SP(&info));
 		if (ret == 0) {
-			_stp_func_print(UNW_PC(&info), verbose, 1, current);
+			_stp_func_print(UNW_PC(&info), verbose, 1, tsk);
 			levels--;
 			continue;
 		}
diff --git a/runtime/stack.c b/runtime/stack.c
index 5dd0cbdc..ee10e25f 100644
--- a/runtime/stack.c
+++ b/runtime/stack.c
@@ -1,6 +1,6 @@
 /*  -*- linux-c -*-
  * Stack tracing functions
- * Copyright (C) 2005-2008 Red Hat Inc.
+ * Copyright (C) 2005-2009 Red Hat Inc.
  * Copyright (C) 2005 Intel Corporation.
  *
  * This file is part of systemtap, and is free software.  You can
@@ -107,7 +107,7 @@ static void _stp_stack_print_fallback(unsigned long stack, int verbose, int leve
  * @param regs A pointer to the struct pt_regs.
  */
 
-static void _stp_stack_print(struct pt_regs *regs, int verbose, struct kretprobe_instance *pi, int levels)
+static void _stp_stack_print(struct pt_regs *regs, int verbose, struct kretprobe_instance *pi, int levels, struct task_struct *tsk)
 {
 	if (verbose) {
 		/* print the current address */
@@ -126,7 +126,7 @@ static void _stp_stack_print(struct pt_regs *regs, int verbose, struct kretprobe
 	else 
 		_stp_printf("%p ", (int64_t) REG_IP(regs));
 
-	__stp_stack_print(regs, verbose, levels);
+	__stp_stack_print(regs, verbose, levels, tsk);
 }
 
 /** Writes stack backtrace to a string
@@ -135,14 +135,14 @@ static void _stp_stack_print(struct pt_regs *regs, int verbose, struct kretprobe
  * @param regs A pointer to the struct pt_regs.
  * @returns void
  */
-static void _stp_stack_snprint(char *str, int size, struct pt_regs *regs, int verbose, struct kretprobe_instance *pi, int levels)
+static void _stp_stack_snprint(char *str, int size, struct pt_regs *regs, int verbose, struct kretprobe_instance *pi, int levels, struct task_struct *tsk)
 {
 	/* To get a string, we use a simple trick. First flush the print buffer, */
 	/* then call _stp_stack_print, then copy the result into the output string  */
 	/* and clear the print buffer. */
 	_stp_pbuf *pb = per_cpu_ptr(Stp_pbuf, smp_processor_id());
 	_stp_print_flush();
-	_stp_stack_print(regs, verbose, pi, levels);
+	_stp_stack_print(regs, verbose, pi, levels, tsk);
 	strlcpy(str, pb->buf, size < (int)pb->len ? size : (int)pb->len);
 	pb->len = 0;
 }
diff --git a/runtime/unwind.c b/runtime/unwind.c
index 7914c77d..aacd56f1 100644
--- a/runtime/unwind.c
+++ b/runtime/unwind.c
@@ -568,7 +568,7 @@ static char *_stp_eh_enc_name(signed type)
 /* Unwind to previous to frame.  Returns 0 if successful, negative
  * number in case of an error.  A positive return means unwinding is finished; 
  * don't try to fallback to dumping addresses on the stack. */
-static int unwind(struct unwind_frame_info *frame)
+static int unwind(struct unwind_frame_info *frame, struct task_struct *tsk)
 {
 #define FRAME_REG(r, t) (((t *)frame)[reg_info[r].offs])
 	const u32 *fde, *cie = NULL;
@@ -587,7 +587,7 @@ static int unwind(struct unwind_frame_info *frame)
 	if (UNW_PC(frame) == 0)
 		return -EINVAL;
 
-	m = _stp_mod_sec_lookup (pc, current, &s);
+	m = _stp_mod_sec_lookup (pc, tsk, &s);
 	if (unlikely(m == NULL)) {
 		dbug_unwind(1, "No module found for pc=%lx", pc);
 		return -EINVAL;