From 0e6644c3880be9684f37f48da84907bb67112514 Mon Sep 17 00:00:00 2001 From: Ben Pfaff Date: Fri, 13 May 2011 11:55:22 -0700 Subject: [PATCH] backtrace: Make backtrace_capture() work on more systems. The backtrace_capture() implementation only worked properly with GNU C on systems that have a simple stack frame with a frame pointer. Notably, the x86-64 ABI by default has no frame pointer, so this failed on x86-64. However, glibc has a function named backtrace() that does what we want. This commit tests for this function and uses it when it is present, fixing x86-64 backtraces. --- configure.ac | 1 + lib/backtrace.c | 30 +++++++++++++++++++++++++----- m4/openvswitch.m4 | 5 +++++ 3 files changed, 31 insertions(+), 5 deletions(-) diff --git a/configure.ac b/configure.ac index 5b5f47ed..fe91242f 100644 --- a/configure.ac +++ b/configure.ac @@ -61,6 +61,7 @@ AC_CHECK_HEADERS([mntent.h sys/statvfs.h]) OVS_CHECK_PKIDIR OVS_CHECK_RUNDIR +OVS_CHECK_BACKTRACE OVS_CHECK_MALLOC_HOOKS OVS_CHECK_VALGRIND OVS_CHECK_SOCKET_LIBS diff --git a/lib/backtrace.c b/lib/backtrace.c index 91549db3..1c0dfd6c 100644 --- a/lib/backtrace.c +++ b/lib/backtrace.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2008, 2009, 2010 Nicira Networks. + * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. @@ -15,17 +15,34 @@ */ #include + #include "backtrace.h" + #include #include #include #include + #include "compiler.h" #include "vlog.h" VLOG_DEFINE_THIS_MODULE(backtrace); -static uintptr_t OVS_UNUSED +#ifdef HAVE_BACKTRACE +#include +void +backtrace_capture(struct backtrace *b) +{ + void *frames[BACKTRACE_MAX_FRAMES]; + int i; + + b->n_frames = backtrace(frames, BACKTRACE_MAX_FRAMES); + for (i = 0; i < b->n_frames; i++) { + b->frames[i] = (uintptr_t) frames[i]; + } +} +#elif __GNUC__ +static uintptr_t get_max_stack(void) { static const char file_name[] = "/proc/self/maps"; @@ -83,7 +100,6 @@ in_stack(void *p) void backtrace_capture(struct backtrace *backtrace) { -#ifdef __GNUC__ void **frame; size_t n; @@ -96,7 +112,11 @@ backtrace_capture(struct backtrace *backtrace) backtrace->frames[n++] = (uintptr_t) frame[1]; } backtrace->n_frames = n; -#else +} +#else /* !HAVE_BACKTRACE && !__GNUC__ */ +void +backtrace_capture(struct backtrace *backtrace) +{ backtrace->n_frames = 0; -#endif } +#endif diff --git a/m4/openvswitch.m4 b/m4/openvswitch.m4 index e6d03a6b..73db4bba 100644 --- a/m4/openvswitch.m4 +++ b/m4/openvswitch.m4 @@ -152,6 +152,11 @@ AC_DEFUN([OVS_CHECK_LOGDIR], [LOGDIR='${localstatedir}/log/${PACKAGE}']) AC_SUBST([LOGDIR])]) +dnl Defines HAVE_BACKTRACE if backtrace() is declared in +dnl and exists in libc. +AC_DEFUN([OVS_CHECK_BACKTRACE], + [AC_CHECK_HEADER([execinfo.h], [AC_CHECK_FUNCS([backtrace])])]) + dnl Checks for __malloc_hook, etc., supported by glibc. AC_DEFUN([OVS_CHECK_MALLOC_HOOKS], [AC_CACHE_CHECK( -- 2.30.2