Hi Ian, On Mon, Jun 5, 2023 at 1:28 PM Ian Rogers <irogers@xxxxxxxxxx> wrote: > > If generating vmlinux.h, make the code to generate it more tolerant by > filtering out paths to kernels that lack a .BTF section. > > Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx> > --- > tools/perf/Makefile.perf | 23 ++++++++++++++++++++--- > 1 file changed, 20 insertions(+), 3 deletions(-) > > diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf > index f1840af195c0..c3bb27a912b0 100644 > --- a/tools/perf/Makefile.perf > +++ b/tools/perf/Makefile.perf > @@ -193,6 +193,7 @@ FLEX ?= flex > BISON ?= bison > STRIP = strip > AWK = awk > +READELF ?= readelf > > # include Makefile.config by default and rule out > # non-config cases > @@ -1080,12 +1081,28 @@ $(BPFTOOL): | $(SKEL_TMP_OUT) > $(Q)CFLAGS= $(MAKE) -C ../bpf/bpftool \ > OUTPUT=$(SKEL_TMP_OUT)/ bootstrap > > -VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux) \ > +# Paths to search for a kernel to generate vmlinux.h from. > +VMLINUX_BTF_ELF_PATHS ?= $(if $(O),$(O)/vmlinux) \ > $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux) \ > ../../vmlinux \ > - /sys/kernel/btf/vmlinux \ > /boot/vmlinux-$(shell uname -r) > -VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS)))) > + > +# Paths to BTF information. > +VMLINUX_BTF_BTF_PATHS ?= /sys/kernel/btf/vmlinux > + > +# Filter out kernels that don't exist or without a BTF section. > +VMLINUX_BTF_ELF_ABSPATHS ?= $(abspath $(wildcard $(VMLINUX_BTF_ELF_PATHS))) > +VMLINUX_BTF_PATHS ?= $(shell for file in $(VMLINUX_BTF_ELF_ABSPATHS); \ > + do \ > + if [ -f $$file ] && ($(READELF) -t "$$file" | grep .BTF); \ Wouldn't it be `readelf -S` instead? Also I think grep needs -q to suppress output. > + then \ > + echo "$$file"; \ > + fi; \ > + done) \ > + $(wildcard $(VMLINUX_BTF_BTF_PATHS)) This changes the order of processing the sysfs file. But I'm not sure it matters much as both /boot/vmlinux and sysfs should refer to the running kernel. Thanks, Namhyung > + > +# Select the first as the source of vmlinux.h. > +VMLINUX_BTF ?= $(firstword $(VMLINUX_BTF_PATHS)) > > $(SKEL_OUT)/vmlinux.h: $(VMLINUX_BTF) $(BPFTOOL) > ifeq ($(VMLINUX_H),) > -- > 2.41.0.rc0.172.g3f132b7071-goog >
