Merge branch 'master' of git://sources.redhat.com/git/systemtap

10 files changed, 92 insertions, 58 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 5a18c9d8..69623765 100644
--- a/runtime/stack-i386.c
+++ b/runtime/stack-i386.c
@@ -23,14 +23,15 @@ static void _stp_stack_print_fallback(unsigned long stack, int verbose, int leve
 			/* cannot access stack.  give up. */
 			return;
 		}
-		if (_stp_func_print(addr, verbose, 0))
+		if (_stp_func_print(addr, verbose, 0, NULL))
 			levels--;
 		stack++;
 	}
 }
 #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);
 
@@ -43,7 +44,7 @@ static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels)
 			/* cannot access stack.  give up. */
 			return;
 		}
-		_stp_func_print(addr, verbose, 1);
+		_stp_func_print(addr, verbose, 1, NULL);
 		if (unlikely(_stp_read_address(next_fp, (unsigned long *)fp, KERNEL_DS))) {
 			/* cannot access stack.  give up. */
 			return;
@@ -60,19 +61,23 @@ 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);
+			_stp_func_print(UNW_PC(&info), verbose, 1, tsk);
 			levels--;
 			continue;
 		}
-		/* If an error happened or we hit a kretprobe trampoline, use fallback backtrace */
-		/* FIXME: is there a way to unwind across kretprobe trampolines? */
-		if (ret < 0 || (ret > 0 && UNW_PC(&info) == _stp_kretprobe_trampoline))
+		/* If an error happened or we hit a kretprobe trampoline,
+		 * use fallback backtrace, unless user task backtrace.
+		 * FIXME: is there a way to unwind across kretprobe
+		 * trampolines? */
+		if ((ret < 0
+		     || (ret > 0 && UNW_PC(&info) == _stp_kretprobe_trampoline))
+		    && ! (tsk || arch_unw_user_mode(&info)))
 			_stp_stack_print_fallback(UNW_SP(&info), verbose, levels);
-		break;
+		return;
 	}
 #else /* ! STP_USE_DWARF_UNWINDER */
 	_stp_stack_print_fallback((unsigned long)&REG_SP(regs), verbose, levels);
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 03d88ef0..9afdf38a 100644
--- a/runtime/stack-x86_64.c
+++ b/runtime/stack-x86_64.c
@@ -19,7 +19,7 @@ static void _stp_stack_print_fallback(unsigned long stack, int verbose, int leve
 			/* cannot access stack.  give up. */
 			return;
 		}
-		if (_stp_func_print(addr, verbose, 0))
+		if (_stp_func_print(addr, verbose, 0, NULL))
 			levels--;
 		stack++;
 	}
@@ -27,26 +27,31 @@ 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);
+			_stp_func_print(UNW_PC(&info), verbose, 1, tsk);
 			levels--;
 			continue;
 		}
-		/* If an error happened or we hit a kretprobe trampoline, use fallback backtrace */
-		/* FIXME: is there a way to unwind across kretprobe trampolines? */
-		if (ret < 0 || (ret > 0 && UNW_PC(&info) == _stp_kretprobe_trampoline))
+		/* If an error happened or we hit a kretprobe trampoline,
+		 * use fallback backtrace, unless user task backtrace.
+		 * FIXME: is there a way to unwind across kretprobe
+		 * trampolines? */
+		if ((ret < 0
+		     || (ret > 0 && UNW_PC(&info) == _stp_kretprobe_trampoline))
+		    && ! (tsk || arch_unw_user_mode(&info)))
 			_stp_stack_print_fallback(UNW_SP(&info), verbose, levels);
-		break;
+		return;
 	}
 #else /* ! STP_USE_DWARF_UNWINDER */
 	_stp_stack_print_fallback(REG_SP(regs), verbose, levels);
diff --git a/runtime/stack.c b/runtime/stack.c
index 68fb9b1f..042f44c7 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
@@ -77,7 +77,7 @@ static void print_stack_address(void *data, unsigned long addr, int reliable)
 {
 	struct print_stack_data *sdata = data;
         if (sdata->level++ < sdata->max_level)
-                _stp_func_print(addr,sdata->verbose, 0);
+                _stp_func_print(addr, sdata->verbose, 0, NULL);
 }
 
 static const struct stacktrace_ops print_stack_ops = {
@@ -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 */
@@ -118,7 +118,10 @@ static void _stp_stack_print(struct pt_regs *regs, int verbose, struct kretprobe
 			_stp_symbol_print((unsigned long)_stp_ret_addr_r(pi));
 		} else {
 			_stp_print_char(' ');
-			_stp_symbol_print(REG_IP(regs));
+			if (tsk)
+			  _stp_usymbol_print(REG_IP(regs), tsk);
+			else
+			  _stp_symbol_print(REG_IP(regs));
 		}
 		_stp_print_char('\n');
 	} else if (pi)
@@ -126,7 +129,7 @@ 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
@@ -135,37 +138,20 @@ 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;
 }
 
 #endif /* CONFIG_KPROBES */
 
-/** Prints the user stack backtrace
- * @param str string
- * @returns Same string as was input with trace info appended,
- * @note Currently limited to a depth of two. Works from jprobes and kprobes.
- */
-#if 0
-static void _stp_ustack_print(char *str)
-{
-	struct pt_regs *nregs = ((struct pt_regs *)(THREAD_SIZE + (unsigned long)current->thread_info)) - 1;
-	_stp_printf("%p : [user]\n", (int64_t) REG_IP(nregs));
-	if (REG_SP(nregs))
-		_stp_printf("%p : [user]\n", (int64_t) (*(unsigned long *)REG_SP(nregs)));
-}
-#endif /* 0 */
-
-/** @} */
-
 void _stp_stack_print_tsk(struct task_struct *tsk, int verbose, int levels)
 {
 #if defined(STAPCONF_KERNEL_STACKTRACE)
diff --git a/runtime/sym.c b/runtime/sym.c
index f6f97ac2..013edd0c 100644
--- a/runtime/sym.c
+++ b/runtime/sym.c
@@ -329,8 +329,35 @@ static void _stp_symbol_print(unsigned long address)
 	}
 }
 
+/** Print an user space address from a specific task symbolically.
+ * @param address The address to lookup.
+ * @param task The address to lookup.
+ * @note Symbolic lookups should not normally be done within
+ * a probe because it is too time-consuming. Use at module exit time.
+ */
+
+static void _stp_usymbol_print(unsigned long address, struct task_struct *task)
+{
+	const char *modname;
+	const char *name;
+	unsigned long offset, size;
+
+	name = _stp_kallsyms_lookup(address, &size, &offset, &modname, NULL,
+                                    task);
+
+	_stp_printf("%p", (int64_t) address);
+
+	if (name) {
+		if (modname && *modname)
+			_stp_printf(" : %s+%#lx/%#lx [%s]", name, offset, size, modname);
+		else
+			_stp_printf(" : %s+%#lx/%#lx", name, offset, size);
+	}
+}
+
 /* Like _stp_symbol_print, except only print if the address is a valid function address */
-static int _stp_func_print(unsigned long address, int verbose, int exact)
+static int _stp_func_print(unsigned long address, int verbose, int exact,
+                           struct task_struct *task)
 {
 	const char *modname;
 	const char *name;
@@ -342,7 +369,7 @@ static int _stp_func_print(unsigned long address, int verbose, int exact)
 	else
 		exstr = " (inexact)";
 
-	name = _stp_kallsyms_lookup(address, &size, &offset, &modname, NULL, NULL);
+	name = _stp_kallsyms_lookup(address, &size, &offset, &modname, NULL, task);
 
 	if (name) {
 		if (verbose) {
diff --git a/runtime/unwind.c b/runtime/unwind.c
index 41af72a7..aacd56f1 100644
--- a/runtime/unwind.c
+++ b/runtime/unwind.c
@@ -435,12 +435,18 @@ adjustStartLoc (unsigned long startLoc,
 		struct _stp_module *m,
 		struct _stp_section *s)
 {
-  if (startLoc && (strcmp (m->name, "kernel") != 0))
-    {
-      startLoc = _stp_module_relocate (m->name, s->name,
-				       startLoc);
-      startLoc -= m->dwarf_module_base;
-    }
+  /* XXX - some, or all, of this should really be done by
+     _stp_module_relocate. */
+  if (startLoc == 0
+      || strcmp (m->name, "kernel")  == 0
+      || strcmp (s->name, ".absolute") == 0)
+    return startLoc;
+
+  if (strcmp (s->name, ".dynamic") == 0)
+    return startLoc + s->addr;
+
+  startLoc = _stp_module_relocate (m->name, s->name, startLoc);
+  startLoc -= m->dwarf_module_base;
   return startLoc;
 }
 
@@ -562,7 +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;
@@ -581,7 +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;
diff --git a/runtime/uprobes2/uprobes.c b/runtime/uprobes2/uprobes.c
index 9ea05349..07ad3984 100644
--- a/runtime/uprobes2/uprobes.c
+++ b/runtime/uprobes2/uprobes.c
@@ -2239,7 +2239,8 @@ static u32 uprobe_report_exit(enum utrace_resume_action action,
 			}
 		}
 		up_read(&uproc->rwsem);
-		if (utask->state == UPTASK_TRAMPOLINE_HIT)
+		if (utask->state == UPTASK_TRAMPOLINE_HIT ||
+						utask->state == UPTASK_BP_HIT)
 			uprobe_decref_process(uproc);
 	}