diff options
Diffstat (limited to 'runtime/stack-x86_64.c')
| -rw-r--r-- | runtime/stack-x86_64.c | 36 |
1 files changed, 30 insertions, 6 deletions
diff --git a/runtime/stack-x86_64.c b/runtime/stack-x86_64.c index 186b2ad4..ae8e446d 100644 --- a/runtime/stack-x86_64.c +++ b/runtime/stack-x86_64.c @@ -1,6 +1,6 @@ /* -*- linux-c -*- * x86_64 stack tracing functions - * Copyright (C) 2005, 2006, 2007 Red Hat Inc. + * Copyright (C) 2005-2008 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 @@ -8,13 +8,37 @@ * later version. */ -static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels) +/* DWARF unwinder failed. Just dump intereting addresses on kernel stack. */ +static void _stp_stack_print_fallback(unsigned long stack, int verbose) { - unsigned long *stack = (unsigned long *)REG_SP(regs); unsigned long addr; + while (stack & (THREAD_SIZE - 1)) { + if (unlikely(_stp_read_address(addr, (unsigned long *)stack, KERNEL_DS))) { + /* cannot access stack. give up. */ + return; + } + _stp_func_print(addr, verbose, 0); + stack++; + } +} + +static void __stp_stack_print(struct pt_regs *regs, int verbose, int levels) +{ + // FIXME: large stack allocation + struct unwind_frame_info info; + arch_unw_init_frame_info(&info, regs); - while ((long)stack & (THREAD_SIZE-1)) { - addr = *stack++; - _stp_func_print(addr, verbose, 1); + while (!arch_unw_user_mode(&info)) { + int ret = unwind(&info); + 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); + 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)) + _stp_stack_print_fallback(UNW_SP(&info), verbose); + break; } } |