From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-dy1-f197.google.com (mail-dy1-f197.google.com [74.125.82.197]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 89892563FAF for ; Tue, 13 Oct 2026 23:14:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.197 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791933284; cv=none; b=JMcW5F+EvxGLXp93ML10kb6kCx0bACyFkV3Fxc09b3JabMt4aqRWxZtE0xX3SnYSTQYyYqFlEv1Sg4mdzAYOvqZa0WZt9Hwz0o/E4tsYR7r6zMwFp3AU3b3jv/R5NlcaT7MnqaD/0I0MvKzc4Rktm/FLKNTM1EdLAejlyHSsAYE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791933284; c=relaxed/simple; bh=blhkNd7YPOHByM6jhZraZMpx6Hjvkwqjwud40X2q32M=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=bZKtykI/GtojH5EJmGXRhG+z2aPscNbmrQMaoz7Dk6Lar2gTTaQACbqGN7FVbPmfrWEsZZFQf26qTD1dpis2C6jXLPcN64HYhq+nBU9cwGiK6foUzY3VnYQLEg5fAhJH7UgQy+fx0rWkaFOOzIEkkunQr6CVlijlfPE7WeSIzds= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--irogers.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=TrdzdBIm; arc=none smtp.client-ip=74.125.82.197 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--irogers.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="TrdzdBIm" Received: by mail-dy1-f197.google.com with SMTP id 5a478bee46e88-35c3c370b17so2487572eec.0 for ; Tue, 13 Oct 2026 16:14:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1791933281; x=1792538081; darn=vger.kernel.org; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:from:to:cc:subject:date:message-id:reply-to :content-type; bh=qYhrg7g0yJ8cu7vKkFE0QJOFgou8b+/PjQRDx5Q9dOk=; b=TrdzdBImLWxvuoJqlWZSFjhpuMu0XJlaGKTpVFT6k2B/dAjWbh/+WeJW+mhQ4EFbUV A/nFv4SryXT8OxfSe1KBLtx26uJFtVC54N1J2txY3O3JducxJhDKexz348ObfgJPQ8nP bOhyIjEZSHbqW/q/OITDzXvmHd3CaDu0GUfTdPT4UUKCjHSHttpDYm5AVI2kdNaqPB6O oSBPj9LdyG451Ueb6FWILNDo4dKQeFy49mwpJz2z2lOzoKNjuKtk0h8Hsad1eDXm+QQv uyghvYjm/iXMYvkeWCQsS5tytMlYecEj6MlF7ykAbUF9PXr+2MXPyDHMJ4whWabE1VNp UV/Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1791933281; x=1792538081; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=qYhrg7g0yJ8cu7vKkFE0QJOFgou8b+/PjQRDx5Q9dOk=; b=TgBZLDwjZtQAxjskfk8OfE/DcoXQqRQX2OGCUahTVUwkZBCyFCe/aB9G0YWM+L6GGE ySbm7XzPAGHjdrJsYQtOpMrDqFxvgYedkHd2ErE09LhRsRwwP5va7+uKBKfb7mH06WGk V8WRnalsYQl5ODEW7Tl5on9vpMIc4zd4wnmaHmGh0/vZU4sPFNbkVpLXgzIqljDtTkFN RZ5zPWbaNkwswKs/l5xhBGQ7X5crrS4uYGWt/2BfKgH7ghxr3EFnUhtC7AZnXp2rwXb9 CqZJRHuqoAMJiFP8+E0AxovmndtyiWntNrORTq5cvct/1YhkZY6/F1vim7zMJO79KPMx jJuQ== X-Forwarded-Encrypted: i=1; AKwUvBzvRSkQYpxFT+SOwnxr6WRZRlI0u7DthKN78iv54PJhlHBq4B7XHTDRRjmsTSD6hxm1XF0DG/P/ZShRPbotO50f@vger.kernel.org X-Gm-Message-State: AFq9FYKFNLs5dXpLUmPqbL3zvGXJ/T1/gf9jKhSmqvI6jotuzEWWrI8Z 9sqLLU8vi2+Vm8b4h3zpSZ156S4ODUyG4E+9p1qXXGXbMBts+3FYMvXVhC6sNDrY45osMTnhrXu 8pCkCNt4cWw== X-Received: from dyx5.prod.google.com ([2002:a05:693c:8205:b0:35c:bd2a:aeb]) (user=irogers job=prod-delivery.src-stubby-dispatcher) by 2002:a05:693c:8103:b0:34a:fc46:35ba with SMTP id 5a478bee46e88-3537dfc6e87mr22274259eec.8.1791933280166; Tue, 13 Oct 2026 16:14:40 -0700 (PDT) Date: Tue, 13 Oct 2026 16:14:29 -0700 In-Reply-To: <20261013231430.2163505-1-irogers@google.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20261013221643.1815686-1-irogers@google.com> <20261013231430.2163505-1-irogers@google.com> X-Mailer: git-send-email 2.56.0.385.gd3acb90ef8-goog Message-ID: <20261013231430.2163505-2-irogers@google.com> Subject: [PATCH v2 1/2] perf build: Support building BPF skeletons with bpf-gcc From: Ian Rogers To: irogers@google.com, acme@kernel.org, cupertino.miranda@oracle.com, jose.marchesi@oracle.com, namhyung@kernel.org Cc: adrian.hunter@intel.com, andrii@kernel.org, eddyz87@gmail.com, james.clark@linaro.org, jolsa@kernel.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, yonghong.song@linux.dev Content-Type: text/plain; charset="UTF-8" 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 $(CC). Also update version-ge3 and version-lt3 in tools/scripts/utilities.mak to split the two version arguments separately in awk so empty or fewer-than-3-component version strings do not shift fields across arguments. Assisted-by: Antigravity:gemini-3.1-pro Signed-off-by: Ian Rogers --- tools/perf/Makefile.config | 83 +++++++++++++++++++++++++++------- tools/perf/Makefile.perf | 8 +++- tools/perf/bpf_skel.mak | 36 ++++++++++----- tools/scripts/Makefile.include | 1 + tools/scripts/utilities.mak | 4 +- 5 files changed, 101 insertions(+), 31 deletions(-) diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config index cafc7be79643..235872e65d8f 100644 --- a/tools/perf/Makefile.config +++ b/tools/perf/Makefile.config @@ -662,27 +662,78 @@ ifeq ($(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 2>/dev/null) + ifneq ($$(BPF_GCC_VERSION),) + ifneq ($$(call version-lt3,$$(BPF_GCC_VERSION),14.0.0),1) + have_bpf_gcc := 1 + endif + 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 - = (10000000 * $$4 + 10000 * $$5 + $$6)) }') +version-ge3 = $(shell awk -v v1="$(1)" -v v2="$(2)" 'BEGIN { split(v1, a, "."); split(v2, b, "."); printf("%d\n", (10000000 * a[1] + 10000 * a[2] + a[3]) >= (10000000 * b[1] + 10000 * b[2] + b[3])) }') # version-lt3 # @@ -196,4 +196,4 @@ version-ge3 = $(shell echo "$(1).$(2)" | awk -F'.' '{ printf("%d\n", (10000000 * # check the flex version to see if we can use compiler warnings as errors for # one of the cases flex generates code C compilers complains about. -version-lt3 = $(shell echo "$(1).$(2)" | awk -F'.' '{ printf("%d\n", (10000000 * $$1 + 10000 * $$2 + $$3) < (10000000 * $$4 + 10000 * $$5 + $$6)) }') +version-lt3 = $(shell awk -v v1="$(1)" -v v2="$(2)" 'BEGIN { split(v1, a, "."); split(v2, b, "."); printf("%d\n", (10000000 * a[1] + 10000 * a[2] + a[3]) < (10000000 * b[1] + 10000 * b[2] + b[3])) }') -- 2.56.0.385.gd3acb90ef8-goog