Add ubacktrace(), print_ustack() and print_ubacktrace().

* runtime/sym.c (_stp_usymbol_print): New function.
* tapset/ucontext-unwind.stp (print_ubacktrace): New tapset function.
  (ubacktrace): Likewise.
* tapset/ucontext-symbols.stp (print_ustack): Likewise.
* testsuite/buildok/ustack.stp: New test for above three functions.

1 files changed, 26 insertions, 0 deletions

diff --git a/runtime/sym.c b/runtime/sym.c
index fe9b800c..013edd0c 100644
--- a/runtime/sym.c
+++ b/runtime/sym.c
@@ -329,6 +329,32 @@ 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,
                            struct task_struct *task)