[PATCH 12/17] perf, tool: Add libunwind dependency for dwarf cfi unwinding

From: Jiri Olsa
Date: Sun Jul 22 2012 - 08:15:48 EST


Adding libunwind to be linked with perf if available. It's required
for the to get dwarf cfi unwinding support.

Also building perf with the dwarf call frame informations by default,
so that we can unwind callchains in perf itself.

Adding LIBUNWIND_DIR Makefile variable allowing user to specify
the directory with libunwind to be linked. This is used for
debug purposes.

Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
---
tools/perf/Makefile | 30 +++++++++++++++++++++++++++++-
tools/perf/config/feature-tests.mak | 25 +++++++++++++++++++++++++
2 files changed, 54 insertions(+), 1 deletions(-)

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index 576db7e..d0c3291 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -38,6 +38,9 @@ include config/utilities.mak
# Define NO_NEWT if you do not want TUI support.
#
# Define NO_DEMANGLE if you do not want C++ symbol demangling.
+#
+# Define NO_LIBUNWIND if you do not want libunwind dependency for dwarf
+# backtrace post unwind.

$(OUTPUT)PERF-VERSION-FILE: .FORCE-PERF-VERSION-FILE
@$(SHELL_PATH) util/PERF-VERSION-GEN $(OUTPUT)
@@ -59,6 +62,7 @@ AR = $(CROSS_COMPILE)ar
ifeq ($(ARCH),i386)
ARCH := x86
NO_PERF_REGS := 0
+ LIBUNWIND_LIBS = -lunwind -lunwind-x86
endif
ifeq ($(ARCH),x86_64)
ARCH := x86
@@ -72,6 +76,7 @@ ifeq ($(ARCH),x86_64)
ARCH_INCLUDE = ../../arch/x86/lib/memcpy_64.S ../../arch/x86/lib/memset_64.S
endif
NO_PERF_REGS := 0
+ LIBUNWIND_LIBS = -lunwind -lunwind-x86_64
endif

# Treat warnings as errors unless directed not to
@@ -92,7 +97,7 @@ ifdef PARSER_DEBUG
PARSER_DEBUG_CFLAGS := -DPARSER_DEBUG
endif

-CFLAGS = -fno-omit-frame-pointer -ggdb3 -Wall -Wextra -std=gnu99 $(CFLAGS_WERROR) $(CFLAGS_OPTIMIZE) $(EXTRA_WARNINGS) $(EXTRA_CFLAGS) $(PARSER_DEBUG_CFLAGS)
+CFLAGS = -fno-omit-frame-pointer -ggdb3 -funwind-tables -Wall -Wextra -std=gnu99 $(CFLAGS_WERROR) $(CFLAGS_OPTIMIZE) $(EXTRA_WARNINGS) $(EXTRA_CFLAGS) $(PARSER_DEBUG_CFLAGS)
EXTLIBS = -lpthread -lrt -lelf -lm
ALL_CFLAGS = $(CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE
ALL_LDFLAGS = $(LDFLAGS)
@@ -456,6 +461,21 @@ ifneq ($(call try-cc,$(SOURCE_DWARF),$(FLAGS_DWARF)),y)
endif # Dwarf support
endif # NO_DWARF

+ifndef NO_LIBUNWIND
+# for linking with debug library, run like:
+# make DEBUG=1 LIBUNWIND_DIR=/opt/libunwind/
+ifdef LIBUNWIND_DIR
+ LIBUNWIND_CFLAGS := -I$(LIBUNWIND_DIR)/include
+ LIBUNWIND_LDFLAGS := -L$(LIBUNWIND_DIR)/lib
+endif
+
+FLAGS_UNWIND=$(LIBUNWIND_CFLAGS) $(ALL_CFLAGS) $(LIBUNWIND_LDFLAGS) $(ALL_LDFLAGS) $(EXTLIBS) $(LIBUNWIND_LIBS)
+ifneq ($(call try-cc,$(SOURCE_LIBUNWIND),$(FLAGS_UNWIND)),y)
+ msg := $(warning No libunwind found. Please install libunwind >= 0.99);
+ NO_LIBUNWIND := 1
+endif # Libunwind support
+endif # NO_LIBUNWIND
+
-include arch/$(ARCH)/Makefile

ifneq ($(OUTPUT),)
@@ -487,6 +507,14 @@ else
endif # PERF_HAVE_DWARF_REGS
endif # NO_DWARF

+ifdef NO_LIBUNWIND
+ BASIC_CFLAGS += -DNO_LIBUNWIND_SUPPORT
+else
+ EXTLIBS += $(LIBUNWIND_LIBS)
+ BASIC_CFLAGS := $(LIBUNWIND_CFLAGS) $(BASIC_CFLAGS)
+ BASIC_LDFLAGS := $(LIBUNWIND_LDFLAGS) $(BASIC_LDFLAGS)
+endif
+
ifdef NO_NEWT
BASIC_CFLAGS += -DNO_NEWT_SUPPORT
else
diff --git a/tools/perf/config/feature-tests.mak b/tools/perf/config/feature-tests.mak
index 6c18785..2f1156a 100644
--- a/tools/perf/config/feature-tests.mak
+++ b/tools/perf/config/feature-tests.mak
@@ -154,3 +154,28 @@ int main(void)
return 0;
}
endef
+
+ifndef NO_LIBUNWIND
+define SOURCE_LIBUNWIND
+#include <libunwind.h>
+#include <stdlib.h>
+
+extern int UNW_OBJ(dwarf_search_unwind_table) (unw_addr_space_t as,
+ unw_word_t ip,
+ unw_dyn_info_t *di,
+ unw_proc_info_t *pi,
+ int need_unwind_info, void *arg);
+
+
+#define dwarf_search_unwind_table UNW_OBJ(dwarf_search_unwind_table)
+
+int main(void)
+{
+ unw_addr_space_t addr_space;
+ addr_space = unw_create_addr_space(NULL, 0);
+ unw_init_remote(NULL, addr_space, NULL);
+ dwarf_search_unwind_table(addr_space, 0, NULL, NULL, 0, NULL);
+ return 0;
+}
+endef
+endif
--
1.7.7.6

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/