| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Tue, 29 Dec 2020 16:01:41 +0900
From: Namhyung Kim <namhyung@...nel.org>
To: Song Liu <songliubraving@...com>
Cc: linux-kernel <linux-kernel@...r.kernel.org>,
Arnaldo Carvalho de Melo <acme@...nel.org>,
Peter Zijlstra <peterz@...radead.org>,
Ingo Molnar <mingo@...hat.com>,
Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
Mark Rutland <mark.rutland@....com>,
Jiri Olsa <jolsa@...hat.com>, kernel-team@...com
Subject: Re: [PATCH v6 2/4] perf: support build BPF skeletons with perf
Hello,
On Tue, Dec 29, 2020 at 2:41 AM Song Liu <songliubraving@...com> wrote:
>
> BPF programs are useful in perf to profile BPF programs. BPF skeleton is
I'm having difficulties understanding the first sentence - looks like a
recursion. :) So do you want to use two (or more) BPF programs?
Thanks,
Namhyung
> by far the easiest way to write BPF tools. Enable building BPF skeletons
> in util/bpf_skel. A dummy bpf skeleton is added. More bpf skeletons will
> be added for different use cases.
>
> Acked-by: Jiri Olsa <jolsa@...hat.com>
> Signed-off-by: Song Liu <songliubraving@...com>
> ---
> tools/build/Makefile.feature | 4 ++-
> tools/perf/Makefile.config | 9 ++++++
> tools/perf/Makefile.perf | 49 +++++++++++++++++++++++++++--
> tools/perf/util/bpf_skel/.gitignore | 3 ++
> tools/scripts/Makefile.include | 1 +
> 5 files changed, 63 insertions(+), 3 deletions(-)
> create mode 100644 tools/perf/util/bpf_skel/.gitignore
>
> diff --git a/tools/build/Makefile.feature b/tools/build/Makefile.feature
> index 97cbfb31b7625..74e255d58d8d0 100644
> --- a/tools/build/Makefile.feature
> +++ b/tools/build/Makefile.feature
> @@ -99,7 +99,9 @@ FEATURE_TESTS_EXTRA := \
> clang \
> libbpf \
> libpfm4 \
> - libdebuginfod
> + libdebuginfod \
> + clang-bpf-co-re
> +
>
> FEATURE_TESTS ?= $(FEATURE_TESTS_BASIC)
>
> diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
> index ce8516e4de34f..d8e59d31399a5 100644
> --- a/tools/perf/Makefile.config
> +++ b/tools/perf/Makefile.config
> @@ -621,6 +621,15 @@ ifndef NO_LIBBPF
> endif
> endif
>
> +ifdef BUILD_BPF_SKEL
> + $(call feature_check,clang-bpf-co-re)
> + ifeq ($(feature-clang-bpf-co-re), 0)
> + dummy := $(error Error: clang too old. Please install recent clang)
> + endif
> + $(call detected,CONFIG_PERF_BPF_SKEL)
> + CFLAGS += -DHAVE_BPF_SKEL
> +endif
> +
> dwarf-post-unwind := 1
> dwarf-post-unwind-text := BUG
>
> diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
> index 62f3deb1d3a8b..d182a2dbb9bbd 100644
> --- a/tools/perf/Makefile.perf
> +++ b/tools/perf/Makefile.perf
> @@ -126,6 +126,8 @@ include ../scripts/utilities.mak
> #
> # Define NO_LIBDEBUGINFOD if you do not want support debuginfod
> #
> +# Define BUILD_BPF_SKEL to enable BPF skeletons
> +#
>
> # As per kernel Makefile, avoid funny character set dependencies
> unexport LC_ALL
> @@ -175,6 +177,12 @@ endef
>
> LD += $(EXTRA_LDFLAGS)
>
> +HOSTCC ?= gcc
> +HOSTLD ?= ld
> +HOSTAR ?= ar
> +CLANG ?= clang
> +LLVM_STRIP ?= llvm-strip
> +
> PKG_CONFIG = $(CROSS_COMPILE)pkg-config
> LLVM_CONFIG ?= llvm-config
>
> @@ -731,7 +739,8 @@ prepare: $(OUTPUT)PERF-VERSION-FILE $(OUTPUT)common-cmds.h archheaders $(drm_ioc
> $(x86_arch_prctl_code_array) \
> $(rename_flags_array) \
> $(arch_errno_name_array) \
> - $(sync_file_range_arrays)
> + $(sync_file_range_arrays) \
> + bpf-skel
>
> $(OUTPUT)%.o: %.c prepare FORCE
> $(Q)$(MAKE) -f $(srctree)/tools/build/Makefile.build dir=$(build-dir) $@
> @@ -1004,7 +1013,43 @@ config-clean:
> python-clean:
> $(python-clean)
>
> -clean:: $(LIBTRACEEVENT)-clean $(LIBAPI)-clean $(LIBBPF)-clean $(LIBSUBCMD)-clean $(LIBPERF)-clean config-clean fixdep-clean python-clean
> +SKEL_OUT := $(abspath $(OUTPUT)util/bpf_skel)
> +SKEL_TMP_OUT := $(abspath $(SKEL_OUT)/.tmp)
> +SKELETONS :=
> +
> +ifdef BUILD_BPF_SKEL
> +BPFTOOL := $(SKEL_TMP_OUT)/bootstrap/bpftool
> +LIBBPF_SRC := $(abspath ../lib/bpf)
> +BPF_INCLUDE := -I$(SKEL_TMP_OUT)/.. -I$(BPF_PATH) -I$(LIBBPF_SRC)/..
> +
> +$(SKEL_TMP_OUT):
> + $(Q)$(MKDIR) -p $@
> +
> +$(BPFTOOL): | $(SKEL_TMP_OUT)
> + CFLAGS= $(MAKE) -C ../bpf/bpftool \
> + OUTPUT=$(SKEL_TMP_OUT)/ bootstrap
> +
> +$(SKEL_TMP_OUT)/%.bpf.o: util/bpf_skel/%.bpf.c $(LIBBPF) | $(SKEL_TMP_OUT)
> + $(QUIET_CLANG)$(CLANG) -g -O2 -target bpf $(BPF_INCLUDE) \
> + -c $(filter util/bpf_skel/%.bpf.c,$^) -o $@ && $(LLVM_STRIP) -g $@
> +
> +$(SKEL_OUT)/%.skel.h: $(SKEL_TMP_OUT)/%.bpf.o | $(BPFTOOL)
> + $(QUIET_GENSKEL)$(BPFTOOL) gen skeleton $< > $@
> +
> +bpf-skel: $(SKELETONS)
> +
> +.PRECIOUS: $(SKEL_TMP_OUT)/%.bpf.o
> +
> +else # BUILD_BPF_SKEL
> +
> +bpf-skel:
> +
> +endif # BUILD_BPF_SKEL
> +
> +bpf-skel-clean:
> + $(call QUIET_CLEAN, bpf-skel) $(RM) -r $(SKEL_TMP_OUT) $(SKELETONS)
> +
> +clean:: $(LIBTRACEEVENT)-clean $(LIBAPI)-clean $(LIBBPF)-clean $(LIBSUBCMD)-clean $(LIBPERF)-clean config-clean fixdep-clean python-clean bpf-skel-clean
> $(call QUIET_CLEAN, core-objs) $(RM) $(LIBPERF_A) $(OUTPUT)perf-archive $(OUTPUT)perf-with-kcore $(LANG_BINDINGS)
> $(Q)find $(if $(OUTPUT),$(OUTPUT),.) -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete
> $(Q)$(RM) $(OUTPUT).config-detected
> diff --git a/tools/perf/util/bpf_skel/.gitignore b/tools/perf/util/bpf_skel/.gitignore
> new file mode 100644
> index 0000000000000..5263e9e6c5d83
> --- /dev/null
> +++ b/tools/perf/util/bpf_skel/.gitignore
> @@ -0,0 +1,3 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +.tmp
> +*.skel.h
> \ No newline at end of file
> diff --git a/tools/scripts/Makefile.include b/tools/scripts/Makefile.include
> index 1358e89cdf7d6..62119ce69ad9a 100644
> --- a/tools/scripts/Makefile.include
> +++ b/tools/scripts/Makefile.include
> @@ -127,6 +127,7 @@ ifneq ($(silent),1)
> $(MAKE) $(PRINT_DIR) -C $$subdir
> QUIET_FLEX = @echo ' FLEX '$@;
> QUIET_BISON = @echo ' BISON '$@;
> + QUIET_GENSKEL = @echo ' GEN-SKEL '$@;
>
> descend = \
> +@...o ' DESCEND '$(1); \
> --
> 2.24.1
>
Powered by blists - more mailing lists