Support building perf BPF skeletons with bpf-gcc (>= 14.0.0) in addition to clang (>= 12.0.1), similar to tools/testing/selftests/bpf/Makefile. When building perf with GCC (CC_NO_CLANG=1), prefer bpf-gcc and fall back to clang if bpf-gcc is unavailable or too old. When building with Clang/LLVM (CC_NO_CLANG=0), prefer clang and fall back to bpf-gcc. Explicit command-line overrides via BPF_GCC=... or CLANG=... are respected, and setting BPF_GCC= or CLANG= to empty disables that compiler. In bpf_skel.mak, pass the bpf-gcc flags (-mcpu=v3, -fno-ident, -DBPF_NO_PRESERVE_ACCESS_INDEX, -Wno-attributes, -D__TARGET_ARCH_$(SRCARCH), and target endianness) and query system include paths from $(CC). Assisted-by: Antigravity:gemini-3.1-pro Signed-off-by: Ian Rogers --- tools/perf/Makefile.config | 81 +++++++++++++++++++++++++++------- tools/perf/Makefile.perf | 8 +++- tools/perf/bpf_skel.mak | 36 ++++++++++----- tools/scripts/Makefile.include | 1 + 4 files changed, 97 insertions(+), 29 deletions(-) diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config index cafc7be79643..6aee2665b64c 100644 --- a/tools/perf/Makefile.config +++ b/tools/perf/Makefile.config @@ -662,27 +662,76 @@ ifeq ($(BUILD_BPF_SKEL),1) else ifeq ($(filter -DHAVE_LIBOPENSSL_SUPPORT, $(CFLAGS)),) $(warning Warning: Disabled BPF skeletons as libopenssl is required) BUILD_BPF_SKEL := 0 - else ifeq ($(call get-executable,$(CLANG)),) - $(warning Warning: Disabled BPF skeletons as clang ($(CLANG)) is missing) - BUILD_BPF_SKEL := 0 - else - CLANG_VERSION := $(shell $(CLANG) --version | head -1 | sed 's/.*clang version \([[:digit:]]\+.[[:digit:]]\+.[[:digit:]]\+\).*/\1/g') - ifeq ($(call version-lt3,$(CLANG_VERSION),12.0.1),1) - $(warning Warning: Disabled BPF skeletons as reliable BTF generation needs at least $(CLANG) version 12.0.1) - BUILD_BPF_SKEL := 0 - endif endif ifeq ($(BUILD_BPF_SKEL),1) - $(call feature_check,clang-bpf-co-re) - ifeq ($(feature-clang-bpf-co-re), 0) - $(warning Warning: Disabled BPF skeletons as clang is too old) + # Prefer bpf-gcc when building with gcc (CC_NO_CLANG=1) and clang when + # building with clang, unless CLANG or BPF_GCC was explicitly specified on + # the command line. Fall back to whichever compiler is available. + prefer_bpf_gcc := $(CC_NO_CLANG) + ifeq ($(origin BPF_GCC),command line) + ifneq ($(BPF_GCC),) + prefer_bpf_gcc := 1 + endif + else ifeq ($(origin CLANG),command line) + ifneq ($(CLANG),) + prefer_bpf_gcc := 0 + endif + endif + + have_bpf_gcc := 0 + have_clang_bpf := 0 + + define check_bpf_gcc + ifneq ($$(call get-executable,$$(BPF_GCC)),) + BPF_GCC_VERSION := $$(shell $$(BPF_GCC) -dumpfullversion -dumpversion 2>/dev/null) + ifneq ($$(call version-lt3,$$(BPF_GCC_VERSION),14.0.0),1) + have_bpf_gcc := 1 + endif + endif + endef + + ifeq ($(prefer_bpf_gcc),1) + $(eval $(check_bpf_gcc)) + endif + + ifeq ($(have_bpf_gcc),0) + ifneq ($(call get-executable,$(CLANG)),) + CLANG_VERSION := $(shell $(CLANG) --version | head -1 | sed 's/.*clang version \([[:digit:]]\+.[[:digit:]]\+.[[:digit:]]\+\).*/\1/g') + ifneq ($(call version-lt3,$(CLANG_VERSION),12.0.1),1) + $(call feature_check,clang-bpf-co-re) + ifeq ($(feature-clang-bpf-co-re), 1) + have_clang_bpf := 1 + endif + endif + endif + endif + + ifeq ($(prefer_bpf_gcc)$(have_clang_bpf),00) + $(eval $(check_bpf_gcc)) + endif + + ifeq ($(have_bpf_gcc),1) + $(call detected,CONFIG_PERF_BPF_SKEL_BPF_GCC) + $(call detected,CONFIG_PERF_BPF_SKEL) + CFLAGS += -DHAVE_BPF_SKEL + else ifeq ($(have_clang_bpf),1) + $(call detected,CONFIG_PERF_BPF_SKEL) + CFLAGS += -DHAVE_BPF_SKEL + else + ifeq ($(call get-executable,$(CLANG))$(call get-executable,$(BPF_GCC)),) + $(warning Warning: Disabled BPF skeletons as clang ($(CLANG)) and bpf-gcc ($(BPF_GCC)) are missing) + else ifneq ($(call get-executable,$(CLANG)),) + ifeq ($(call version-lt3,$(CLANG_VERSION),12.0.1),1) + $(warning Warning: Disabled BPF skeletons as reliable BTF generation needs at least $(CLANG) version 12.0.1) + else + $(warning Warning: Disabled BPF skeletons as clang is too old) + endif + else + $(warning Warning: Disabled BPF skeletons as bpf-gcc ($(BPF_GCC)) needs at least version 14.0.0) + endif BUILD_BPF_SKEL := 0 endif endif - ifeq ($(BUILD_BPF_SKEL),1) - $(call detected,CONFIG_PERF_BPF_SKEL) - CFLAGS += -DHAVE_BPF_SKEL - endif endif ifndef GEN_VMLINUX_H diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf index 2d9379fea267..4061a79cae54 100644 --- a/tools/perf/Makefile.perf +++ b/tools/perf/Makefile.perf @@ -37,6 +37,9 @@ include ../scripts/utilities.mak # Define EXTRA_BPF_FLAGS="--sysroot=" or other custom include paths for # cross-compiling BPF skeletons # +# Define BPF_GCC to point to the bpf-gcc binary if the default `bpf-gcc' is not +# correct, or set BPF_GCC= to disable using bpf-gcc for BPF skeletons. +# # Define EXCLUDE_EXTLIBS=-lmylib to exclude libmylib from the auto-generated # EXTLIBS. # @@ -208,6 +211,7 @@ FIND = find INSTALL = install FLEX ?= flex BISON ?= bison +BPF_GCC ?= bpf-gcc AWK = awk # include Makefile.config by default and rule out @@ -321,8 +325,8 @@ ifneq ($(force_fixdep),1) endif endif -export srctree OUTPUT RM CC CXX RUSTC CLANG LD AR CFLAGS CXXFLAGS RUST_FLAGS V BISON FLEX AWK LIBBPF READELF -export HOSTCC HOSTLD HOSTAR HOSTCFLAGS SHELLCHECK MYPY PYLINT CONFIG_PERF_BPF_SKEL +export srctree OUTPUT RM CC CXX RUSTC CLANG BPF_GCC LD AR CFLAGS CXXFLAGS RUST_FLAGS V BISON FLEX AWK LIBBPF READELF +export HOSTCC HOSTLD HOSTAR HOSTCFLAGS SHELLCHECK MYPY PYLINT CONFIG_PERF_BPF_SKEL CONFIG_PERF_BPF_SKEL_BPF_GCC include $(srctree)/tools/build/Makefile.include diff --git a/tools/perf/bpf_skel.mak b/tools/perf/bpf_skel.mak index f2559de39f96..7b7edf506509 100644 --- a/tools/perf/bpf_skel.mak +++ b/tools/perf/bpf_skel.mak @@ -22,21 +22,35 @@ bpf-skel-prepare: $(BPFTOOL) $(VMLINUX_H) define get_sys_includes $(shell $(1) $(2) -v -E - &1 \ | sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }') \ -$(shell $(1) $(2) -dM -E -