bpftool: Group libbfd defs in Makefile, only pass them if we use libbfd

Bpftool uses libbfd for disassembling JIT-ed programs. But the feature
is optional, and the tool can be compiled without libbfd support. The
Makefile sets the relevant variables accordingly. It also sets variables
related to libbfd's interface, given that it has changed over time.

Group all those libbfd-related definitions so that it's easier to
understand what we are testing for, and only use variables related to
libbfd's interface if we need libbfd in the first place.

In addition to make the Makefile clearer, grouping the definitions
related to disassembling JIT-ed programs will help support alternatives
to libbfd.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Tested-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20221025150329.97371-5-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Quentin Monnet 2022-10-25 16:03:25 +01:00 committed by Alexei Starovoitov
parent 108326d6fa
commit 2ea4d86a50

View File

@ -124,13 +124,6 @@ include $(FEATURES_DUMP)
endif
endif
ifeq ($(feature-disassembler-four-args), 1)
CFLAGS += -DDISASM_FOUR_ARGS_SIGNATURE
endif
ifeq ($(feature-disassembler-init-styled), 1)
CFLAGS += -DDISASM_INIT_STYLED
endif
LIBS = $(LIBBPF) -lelf -lz
LIBS_BOOTSTRAP = $(LIBBPF_BOOTSTRAP) -lelf -lz
ifeq ($(feature-libcap), 1)
@ -142,9 +135,7 @@ include $(wildcard $(OUTPUT)*.d)
all: $(OUTPUT)bpftool
BFD_SRCS = jit_disasm.c
SRCS = $(filter-out $(BFD_SRCS),$(wildcard *.c))
SRCS := $(wildcard *.c)
ifeq ($(feature-libbfd),1)
LIBS += -lbfd -ldl -lopcodes
@ -154,9 +145,21 @@ else ifeq ($(feature-libbfd-liberty-z),1)
LIBS += -lbfd -ldl -lopcodes -liberty -lz
endif
# If one of the above feature combinations is set, we support libbfd
ifneq ($(filter -lbfd,$(LIBS)),)
CFLAGS += -DHAVE_LIBBFD_SUPPORT
SRCS += $(BFD_SRCS)
CFLAGS += -DHAVE_LIBBFD_SUPPORT
# Libbfd interface changed over time, figure out what we need
ifeq ($(feature-disassembler-four-args), 1)
CFLAGS += -DDISASM_FOUR_ARGS_SIGNATURE
endif
ifeq ($(feature-disassembler-init-styled), 1)
CFLAGS += -DDISASM_INIT_STYLED
endif
endif
ifeq ($(filter -DHAVE_LIBBFD_SUPPORT,$(CFLAGS)),)
# No support for JIT disassembly
SRCS := $(filter-out jit_disasm.c,$(SRCS))
endif
HOST_CFLAGS = $(subst -I$(LIBBPF_INCLUDE),-I$(LIBBPF_BOOTSTRAP_INCLUDE),\