perf symbols: Support minimal build without libelf

Now we have isolated all ELF-specific stuff, it's possible to build
without libelf. The output binary can do most of jobs but lacks (user
level) symbol information - kernel symbols are still accessable thanks
to the kallsyms.

To build perf without libelf (elfutils), give NO_LIBELF=1 to make.

For now, only 'perf probe' command is removed since it depends on
libelf/libdw heavily.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1344228082-15569-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 43 insertions, 14 deletions

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index f790e3b..de6aa8c 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -37,7 +37,12 @@ include config/utilities.mak
 #
 # Define NO_NEWT if you do not want TUI support.
 #
+# Define NO_GTK2 if you do not want GTK+ GUI support.
+#
 # Define NO_DEMANGLE if you do not want C++ symbol demangling.
+#
+# Define NO_LIBELF if you do not want libelf dependency (e.g. cross-builds)
+#
 
 $(OUTPUT)PERF-VERSION-FILE: .FORCE-PERF-VERSION-FILE
 	@$(SHELL_PATH) util/PERF-VERSION-GEN $(OUTPUT)
@@ -450,34 +455,57 @@ PYRF_OBJS += $(OUTPUT)util/xyarray.o
 -include config.mak.autogen
 -include config.mak
 
-ifndef NO_DWARF
-FLAGS_DWARF=$(ALL_CFLAGS) -ldw -lelf $(ALL_LDFLAGS) $(EXTLIBS)
-ifneq ($(call try-cc,$(SOURCE_DWARF),$(FLAGS_DWARF)),y)
-	msg := $(warning No libdw.h found or old libdw.h found or elfutils is older than 0.138, disables dwarf support. Please install new elfutils-devel/libdw-dev);
+ifdef NO_LIBELF
 	NO_DWARF := 1
-endif # Dwarf support
-endif # NO_DWARF
-
--include arch/$(ARCH)/Makefile
-
-ifneq ($(OUTPUT),)
-	BASIC_CFLAGS += -I$(OUTPUT)
-endif
-
+	NO_DEMANGLE := 1
+else
 FLAGS_LIBELF=$(ALL_CFLAGS) $(ALL_LDFLAGS) $(EXTLIBS)
 ifneq ($(call try-cc,$(SOURCE_LIBELF),$(FLAGS_LIBELF)),y)
 	FLAGS_GLIBC=$(ALL_CFLAGS) $(ALL_LDFLAGS)
 	ifneq ($(call try-cc,$(SOURCE_GLIBC),$(FLAGS_GLIBC)),y)
 		msg := $(error No gnu/libc-version.h found, please install glibc-dev[el]/glibc-static);
 	else
-		msg := $(error No libelf.h/libelf found, please install libelf-dev/elfutils-libelf-devel);
+		NO_LIBELF := 1
+		NO_DWARF := 1
+		NO_DEMANGLE := 1
 	endif
 endif
+endif # NO_LIBELF
+
+-include arch/$(ARCH)/Makefile
+
+ifneq ($(OUTPUT),)
+	BASIC_CFLAGS += -I$(OUTPUT)
+endif
+
+ifdef NO_LIBELF
+BASIC_CFLAGS += -DNO_LIBELF_SUPPORT
+
+EXTLIBS := $(filter-out -lelf,$(EXTLIBS))
+
+# Remove ELF/DWARF dependent codes
+LIB_OBJS := $(filter-out $(OUTPUT)util/symbol-elf.o,$(LIB_OBJS))
+LIB_OBJS := $(filter-out $(OUTPUT)util/dwarf-aux.o,$(LIB_OBJS))
+LIB_OBJS := $(filter-out $(OUTPUT)util/probe-event.o,$(LIB_OBJS))
+LIB_OBJS := $(filter-out $(OUTPUT)util/probe-finder.o,$(LIB_OBJS))
+
+BUILTIN_OBJS := $(filter-out $(OUTPUT)builtin-probe.o,$(BUILTIN_OBJS))
+
+# Use minimal symbol handling
+LIB_OBJS += $(OUTPUT)util/symbol-minimal.o
+
+else # NO_LIBELF
 
 ifneq ($(call try-cc,$(SOURCE_ELF_MMAP),$(FLAGS_COMMON)),y)
 	BASIC_CFLAGS += -DLIBELF_NO_MMAP
 endif
 
+FLAGS_DWARF=$(ALL_CFLAGS) -ldw -lelf $(ALL_LDFLAGS) $(EXTLIBS)
+ifneq ($(call try-cc,$(SOURCE_DWARF),$(FLAGS_DWARF)),y)
+	msg := $(warning No libdw.h found or old libdw.h found or elfutils is older than 0.138, disables dwarf support. Please install new elfutils-devel/libdw-dev);
+	NO_DWARF := 1
+endif # Dwarf support
+
 ifndef NO_DWARF
 ifeq ($(origin PERF_HAVE_DWARF_REGS), undefined)
 	msg := $(warning DWARF register mappings have not been defined for architecture $(ARCH), DWARF support disabled);
@@ -488,6 +516,7 @@ else
 	LIB_OBJS += $(OUTPUT)util/dwarf-aux.o
 endif # PERF_HAVE_DWARF_REGS
 endif # NO_DWARF
+endif # NO_LIBELF
 
 ifdef NO_NEWT
 	BASIC_CFLAGS += -DNO_NEWT_SUPPORT