lib: print a stack trace when a test assertion fails

Add an optional dependency on libunwind to print stack traces when a
test assertion fails.

Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Thomas Wood <thomas.wood@intel.com>

benchmarks/Makefile.am

@@ -2,5 +2,5 @@
 include Makefile.sources
 
 AM_CPPFLAGS = -I$(top_srcdir) -I$(top_srcdir)/lib
-AM_CFLAGS = $(DRM_CFLAGS) $(CWARNFLAGS) $(CAIRO_CFLAGS)
+AM_CFLAGS = $(DRM_CFLAGS) $(CWARNFLAGS) $(CAIRO_CFLAGS) $(LIBUNWIND_CFLAGS)
-LDADD = $(top_builddir)/lib/libintel_tools.la $(DRM_LIBS) $(PCIACCESS_LIBS) $(CAIRO_LIBS)
+LDADD = $(top_builddir)/lib/libintel_tools.la $(DRM_LIBS) $(PCIACCESS_LIBS) $(CAIRO_LIBS) $(LIBUNWIND_LIBS)

configure.ac

@@ -187,6 +187,15 @@ AM_CONDITIONAL(BUILD_SHADER_DEBUGGER, [test "x$BUILD_SHADER_DEBUGGER" != xno])
 AS_IF([test "x$BUILD_SHADER_DEBUGGER" != xno],
       [enable_debugger=yes], [enable_debugger=no])
 
+AC_ARG_WITH(libunwind,
+	    AS_HELP_STRING([--without-libunwind],
+			   [Build tests without libunwind support]),
+	    [], [with_libunwind=yes])
+if test "x$with_libunwind" = xyes; then
+	PKG_CHECK_MODULES(LIBUNWIND, libunwind, AC_DEFINE(HAVE_LIBUNWIND, 1, [libunwind support]),
+			  AC_MSG_ERROR([libunwind not found. Use --without-libunwind to disable libunwind support.]))
+fi
+
 # -----------------------------------------------------------------------------
 
 # To build multithread code, gcc uses -pthread, Solaris Studio cc uses -mt
@@ -243,6 +252,7 @@ echo ""
 echo " • Tests:"
 echo "       Build tests        : ${BUILD_TESTS}"
 echo "       Compile prime tests: ${NOUVEAU}"
+echo "       Print stack traces : ${with_libunwind}"
 echo ""
 echo " • Tools:"
 echo "       Assembler          : ${enable_assembler}"

debugger/Makefile.am

@@ -12,6 +12,7 @@ AM_CFLAGS = 			\
 	$(DRM_CFLAGS) 		\
 	$(PCIACCESS_CFLAGS) 	\
 	$(CAIRO_CFLAGS)		\
+	$(LIBUNWIND_CFLAGS)	\
 	$(CWARNFLAGS)
 
-LDADD = $(top_builddir)/lib/libintel_tools.la $(DRM_LIBS) $(PCIACCESS_LIBS) $(CAIRO_LIBS)
+LDADD = $(top_builddir)/lib/libintel_tools.la $(DRM_LIBS) $(PCIACCESS_LIBS) $(CAIRO_LIBS) $(LIBUNWIND_LIBS)

demos/Makefile.am

@@ -3,5 +3,5 @@ bin_PROGRAMS = 				\
 	$(NULL)
 
 AM_CPPFLAGS = -I$(top_srcdir) -I$(top_srcdir)/lib
-AM_CFLAGS = $(DRM_CFLAGS) $(PCIACCESS_CFLAGS) $(CWARNFLAGS) $(CAIRO_CFLAGS)
+AM_CFLAGS = $(DRM_CFLAGS) $(PCIACCESS_CFLAGS) $(CWARNFLAGS) $(CAIRO_CFLAGS) $(LIBUNWIND_CFLAGS)
-LDADD = $(top_builddir)/lib/libintel_tools.la $(DRM_LIBS) $(PCIACCESS_LIBS) $(CAIRO_LIBS)
+LDADD = $(top_builddir)/lib/libintel_tools.la $(DRM_LIBS) $(PCIACCESS_LIBS) $(CAIRO_LIBS) $(LIBUNWIND_LIBS)

lib/Makefile.am

@@ -9,12 +9,11 @@ noinst_LTLIBRARIES = libintel_tools.la
 noinst_HEADERS = check-ndebug.h
 
 AM_CPPFLAGS = -I$(top_srcdir)
-AM_CFLAGS = $(DRM_CFLAGS) $(CWARNFLAGS)  \
+AM_CFLAGS = $(DRM_CFLAGS) $(CWARNFLAGS) $(LIBUNWIND_CFLAGS) \
 	    -DIGT_DATADIR=\""$(abs_top_srcdir)/tests"\" \
 	    -DIGT_LOG_DOMAIN=\""$(subst _,-,$*)"\" \
 	    -pthread
 
-
+LDADD = $(CAIRO_LIBS) $(LIBUNWIND_LIBS)
-LDADD = $(CAIRO_LIBS)
 AM_CFLAGS += $(CAIRO_CFLAGS)
 

lib/igt_core.c

@@ -962,6 +962,33 @@ static bool run_under_gdb(void)
 		strncmp(basename(buf), "gdb", 3) == 0);
 }
 
+#ifdef HAVE_LIBUNWIND
+#define UNW_LOCAL_ONLY
+#include <libunwind.h>
+
+static void print_backtrace(void)
+{
+	unw_cursor_t cursor;
+	unw_context_t uc;
+	int stack_num = 0;
+
+	printf("Stack trace:\n");
+
+	unw_getcontext(&uc);
+	unw_init_local(&cursor, &uc);
+	while (unw_step(&cursor) > 0) {
+		char name[255];
+		unw_word_t off;
+
+		if (unw_get_proc_name(&cursor, name, 255, &off) < 0)
+			strcpy(name, "<unknown>");
+
+		printf("  #%d [%s+0x%x]\n", stack_num++, name,
+		       (unsigned int) off);
+	}
+}
+#endif
+
 void __igt_fail_assert(int exitcode, const char *domain, const char *file,
 		       const int line, const char *func, const char *assertion,
 		       const char *f, ...)
@@ -983,6 +1010,10 @@ void __igt_fail_assert(int exitcode, const char *domain, const char *file,
 		va_end(args);
 	}
 
+#ifdef HAVE_LIBUNWIND
+	print_backtrace();
+#endif
+
 	if (run_under_gdb())
 		abort();
 	igt_fail(exitcode);

tests/Makefile.am

@@ -37,9 +37,10 @@ AM_CFLAGS = $(DRM_CFLAGS) $(CWARNFLAGS) \
 	-I$(srcdir)/../lib \
 	-include "$(srcdir)/../lib/check-ndebug.h" \
 	-DIGT_DATADIR=\""$(abs_srcdir)"\" \
+	$(LIBUNWIND_CFLAGS) \
 	$(NULL)
 
-LDADD = ../lib/libintel_tools.la $(PCIACCESS_LIBS) $(DRM_LIBS) 
+LDADD = ../lib/libintel_tools.la $(PCIACCESS_LIBS) $(DRM_LIBS) $(LIBUNWIND_LIBS)
 
 LDADD += $(CAIRO_LIBS) $(LIBUDEV_LIBS) $(GLIB_LIBS)
 AM_CFLAGS += $(CAIRO_CFLAGS) $(LIBUDEV_CFLAGS) $(GLIB_CFLAGS)

tools/Makefile.am

@@ -7,6 +7,6 @@ SUBDIRS += quick_dump
 endif
 
 AM_CPPFLAGS = -I$(top_srcdir) -I$(top_srcdir)/lib
-AM_CFLAGS = $(DRM_CFLAGS) $(PCIACCESS_CFLAGS) $(CWARNFLAGS) $(CAIRO_CFLAGS)
+AM_CFLAGS = $(DRM_CFLAGS) $(PCIACCESS_CFLAGS) $(CWARNFLAGS) $(CAIRO_CFLAGS) $(LIBUNWIND_CFLAGS)
-LDADD = $(top_builddir)/lib/libintel_tools.la $(DRM_LIBS) $(PCIACCESS_LIBS) $(CAIRO_LIBS) $(LIBUDEV_LIBS)
+LDADD = $(top_builddir)/lib/libintel_tools.la $(DRM_LIBS) $(PCIACCESS_LIBS) $(CAIRO_LIBS) $(LIBUDEV_LIBS) $(LIBUNWIND_LIBS)