From 4c5ce7a55108edb5203b3d69949f09c2284f1963 Mon Sep 17 00:00:00 2001 From: Tim Moore Date: Wed, 16 Dec 2009 18:04:34 +0100 Subject: backtrace through uprobes trampoline. Only works in uretprobes for the moment. * runtime/stack-x86_64.c (__stp_stack_print): Rewrite trampoline PC addresses if necessary. * runtime/stack-i386.c (__stp_stack_print): ditto * runtime/stack-arm.c (__stp_stack_print): Add extra argument * runtime/stack-ppc.c (__stp_stack_print): ditto * runtime/stack-s390.c (__stp_stack_print): ditto * runtime/stack.c (_stap_stack_print): call __stp_stack_print with uretprobe_instance. * testsuite/systemtap.context/uprobe_backtrace.stp: new test --- runtime/stack-x86_64.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'runtime/stack-x86_64.c') diff --git a/runtime/stack-x86_64.c b/runtime/stack-x86_64.c index 914242e0..3fc203f7 100644 --- a/runtime/stack-x86_64.c +++ b/runtime/stack-x86_64.c @@ -28,15 +28,25 @@ static void _stp_stack_print_fallback(unsigned long stack, int verbose, int leve static void __stp_stack_print(struct pt_regs *regs, int verbose, int levels, - struct task_struct *tsk) + struct task_struct *tsk, struct uretprobe_instance *ri) { #ifdef STP_USE_DWARF_UNWINDER + int start_levels = levels; // FIXME: large stack allocation struct unwind_frame_info info; arch_unw_init_frame_info(&info, regs); while (levels && (tsk || !arch_unw_user_mode(&info))) { int ret = unwind(&info, tsk); + unsigned long maybe_pc = 0; + if (ri) { + maybe_pc = uprobe_get_pc(ri, UNW_PC(&info), + UNW_SP(&info)); + if (!maybe_pc) + printk("SYSTEMTAP ERROR: uprobe_get_return returned 0\n"); + else + UNW_PC(&info) = maybe_pc; + } 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, tsk); -- cgit From d5a2bd44d30b45b6829eb27d70ffb6ceaa70c5bd Mon Sep 17 00:00:00 2001 From: Tim Moore Date: Thu, 17 Dec 2009 16:18:34 +0100 Subject: support for a brief backtrace format This only prints symbol+offset, or an address if the symbol isn't known. * runtime/runtime.h (SYM_VERBOSE_NO, SYM_VERBOSE_FULL, SYM_VERBOSE_BRIEF): new constants * runtime/stack.c (_stp_stack_print): support brief format * runtime/sym.c (_stp_func_print): ditto * tapset/ucontext-unwind.stp (print_ubacktrace_brief): new function * testsuite/systemtap.context/fib.c: new test program * testsuite/systemtap.context/fib.stp: new test * testsuite/systemtap.context/fib.exp: new test --- runtime/stack-x86_64.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'runtime/stack-x86_64.c') diff --git a/runtime/stack-x86_64.c b/runtime/stack-x86_64.c index 3fc203f7..80ebd3e7 100644 --- a/runtime/stack-x86_64.c +++ b/runtime/stack-x86_64.c @@ -38,6 +38,7 @@ static void __stp_stack_print(struct pt_regs *regs, int verbose, int levels, while (levels && (tsk || !arch_unw_user_mode(&info))) { int ret = unwind(&info, tsk); +#if UPROBES_API_VERSION > 1 unsigned long maybe_pc = 0; if (ri) { maybe_pc = uprobe_get_pc(ri, UNW_PC(&info), @@ -47,6 +48,7 @@ static void __stp_stack_print(struct pt_regs *regs, int verbose, int levels, else UNW_PC(&info) = maybe_pc; } +#endif 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, tsk); -- cgit