mirror of
https://github.com/eunomia-bpf/bpf-developer-tutorial.git
synced 2026-04-15 02:29:59 +08:00
add submodule from libbpf-bootstrap
This commit is contained in:
yunwei37
9
.gitmodules
vendored
Normal file
9
.gitmodules
vendored
Normal file
@@ -0,0 +1,9 @@
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[submodule "libbpf"]
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path = libbpf
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url = https://github.com/libbpf/libbpf.git
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[submodule "bpftool"]
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path = bpftool
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url = https://github.com/libbpf/bpftool
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[submodule "blazesym"]
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path = blazesym
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url = https://github.com/libbpf/blazesym
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1
blazesym
Submodule
1
blazesym
Submodule
Submodule blazesym added at 35abf6e1cd
138
src/12-profile/Makefile
Normal file
138
src/12-profile/Makefile
Normal file
@@ -0,0 +1,138 @@
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# SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
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OUTPUT := .output
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CLANG ?= clang
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LIBBPF_SRC := $(abspath ../../libbpf/src)
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BPFTOOL_SRC := $(abspath ../../bpftool/src)
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LIBBPF_OBJ := $(abspath $(OUTPUT)/libbpf.a)
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BPFTOOL_OUTPUT ?= $(abspath $(OUTPUT)/bpftool)
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BPFTOOL ?= $(BPFTOOL_OUTPUT)/bootstrap/bpftool
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ARCH ?= $(shell uname -m | sed 's/x86_64/x86/' \
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| sed 's/arm.*/arm/' \
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| sed 's/aarch64/arm64/' \
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| sed 's/ppc64le/powerpc/' \
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| sed 's/mips.*/mips/' \
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| sed 's/riscv64/riscv/' \
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| sed 's/loongarch64/loongarch/')
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VMLINUX := ../../vmlinux/$(ARCH)/vmlinux.h
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# Use our own libbpf API headers and Linux UAPI headers distributed with
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# libbpf to avoid dependency on system-wide headers, which could be missing or
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# outdated
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INCLUDES := -I$(OUTPUT) -I../../libbpf/include/uapi -I$(dir $(VMLINUX))
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CFLAGS := -g -Wall
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ALL_LDFLAGS := $(LDFLAGS) $(EXTRA_LDFLAGS)
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APPS = minimal minimal_legacy bootstrap uprobe kprobe fentry usdt sockfilter tc ksyscall
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CARGO ?= $(shell which cargo)
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ifeq ($(strip $(CARGO)),)
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BZS_APPS :=
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else
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BZS_APPS := profile
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APPS += $(BZS_APPS)
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# Required by libblazesym
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ALL_LDFLAGS += -lrt -ldl -lpthread -lm
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endif
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# Get Clang's default includes on this system. We'll explicitly add these dirs
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# to the includes list when compiling with `-target bpf` because otherwise some
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# architecture-specific dirs will be "missing" on some architectures/distros -
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# headers such as asm/types.h, asm/byteorder.h, asm/socket.h, asm/sockios.h,
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# sys/cdefs.h etc. might be missing.
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#
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# Use '-idirafter': Don't interfere with include mechanics except where the
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# build would have failed anyways.
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CLANG_BPF_SYS_INCLUDES ?= $(shell $(CLANG) -v -E - </dev/null 2>&1 \
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| sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }')
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ifeq ($(V),1)
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Q =
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msg =
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else
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Q = @
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msg = @printf ' %-8s %s%s\n' \
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"$(1)" \
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"$(patsubst $(abspath $(OUTPUT))/%,%,$(2))" \
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"$(if $(3), $(3))";
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MAKEFLAGS += --no-print-directory
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endif
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define allow-override
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$(if $(or $(findstring environment,$(origin $(1))),\
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$(findstring command line,$(origin $(1)))),,\
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$(eval $(1) = $(2)))
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endef
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$(call allow-override,CC,$(CROSS_COMPILE)cc)
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$(call allow-override,LD,$(CROSS_COMPILE)ld)
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.PHONY: all
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all: $(APPS)
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.PHONY: clean
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clean:
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$(call msg,CLEAN)
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$(Q)rm -rf $(OUTPUT) $(APPS)
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$(OUTPUT) $(OUTPUT)/libbpf $(BPFTOOL_OUTPUT):
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$(call msg,MKDIR,$@)
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$(Q)mkdir -p $@
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# Build libbpf
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$(LIBBPF_OBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(OUTPUT)/libbpf
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$(call msg,LIB,$@)
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$(Q)$(MAKE) -C $(LIBBPF_SRC) BUILD_STATIC_ONLY=1 \
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OBJDIR=$(dir $@)/libbpf DESTDIR=$(dir $@) \
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INCLUDEDIR= LIBDIR= UAPIDIR= \
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install
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# Build bpftool
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$(BPFTOOL): | $(BPFTOOL_OUTPUT)
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$(call msg,BPFTOOL,$@)
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$(Q)$(MAKE) ARCH= CROSS_COMPILE= OUTPUT=$(BPFTOOL_OUTPUT)/ -C $(BPFTOOL_SRC) bootstrap
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$(LIBBLAZESYM_SRC)/target/release/libblazesym.a::
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$(Q)cd $(LIBBLAZESYM_SRC) && $(CARGO) build --features=cheader,dont-generate-test-files --release
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$(LIBBLAZESYM_OBJ): $(LIBBLAZESYM_SRC)/target/release/libblazesym.a | $(OUTPUT)
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$(call msg,LIB, $@)
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$(Q)cp $(LIBBLAZESYM_SRC)/target/release/libblazesym.a $@
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$(LIBBLAZESYM_HEADER): $(LIBBLAZESYM_SRC)/target/release/libblazesym.a | $(OUTPUT)
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$(call msg,LIB,$@)
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$(Q)cp $(LIBBLAZESYM_SRC)/target/release/blazesym.h $@
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# Build BPF code
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$(OUTPUT)/%.bpf.o: %.bpf.c $(LIBBPF_OBJ) $(wildcard %.h) $(VMLINUX) | $(OUTPUT) $(BPFTOOL)
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$(call msg,BPF,$@)
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$(Q)$(CLANG) -g -O2 -target bpf -D__TARGET_ARCH_$(ARCH) \
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$(INCLUDES) $(CLANG_BPF_SYS_INCLUDES) \
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-c $(filter %.c,$^) -o $(patsubst %.bpf.o,%.tmp.bpf.o,$@)
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$(Q)$(BPFTOOL) gen object $@ $(patsubst %.bpf.o,%.tmp.bpf.o,$@)
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# Generate BPF skeletons
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$(OUTPUT)/%.skel.h: $(OUTPUT)/%.bpf.o | $(OUTPUT) $(BPFTOOL)
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$(call msg,GEN-SKEL,$@)
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$(Q)$(BPFTOOL) gen skeleton $< > $@
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# Build user-space code
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$(patsubst %,$(OUTPUT)/%.o,$(APPS)): %.o: %.skel.h
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$(OUTPUT)/%.o: %.c $(wildcard %.h) | $(OUTPUT)
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$(call msg,CC,$@)
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$(Q)$(CC) $(CFLAGS) $(INCLUDES) -c $(filter %.c,$^) -o $@
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$(patsubst %,$(OUTPUT)/%.o,$(BZS_APPS)): $(LIBBLAZESYM_HEADER)
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$(BZS_APPS): $(LIBBLAZESYM_OBJ)
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# Build application binary
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$(APPS): %: $(OUTPUT)/%.o $(LIBBPF_OBJ) | $(OUTPUT)
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$(call msg,BINARY,$@)
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$(Q)$(CC) $(CFLAGS) $^ $(ALL_LDFLAGS) -lelf -lz -o $@
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# delete failed targets
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.DELETE_ON_ERROR:
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# keep intermediate (.skel.h, .bpf.o, etc) targets
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.SECONDARY:
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@@ -1,83 +1,89 @@
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## eBPF 入门实践教程：编写 eBPF 程序 profile 进行性能分析
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# eBPF 入门实践教程：编写 eBPF 程序 profile 进行性能分析
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### 背景
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## 背景
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`profile` 是一款用户追踪程序执行调用流程的工具，类似于perf中的 -g 指令。但是相较于perf而言，
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`profile` 是一款用户追踪程序执行调用流程的工具，类似于perf中的 -g 指令。但是相较于perf而言，
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`profile`的功能更为细化，它可以选择用户需要追踪的层面，比如在用户态层面进行追踪，或是在内核态进行追踪。
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`profile`的功能更为细化，它可以选择用户需要追踪的层面，比如在用户态层面进行追踪，或是在内核态进行追踪。
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### 实现原理
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## 实现原理
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`profile` 的实现依赖于linux中的perf_event。在注入ebpf程序前，`profile` 工具会先将 perf_event
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`profile` 的实现依赖于linux中的perf_event。在注入ebpf程序前，`profile` 工具会先将 perf_event
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注册好。
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注册好。
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```c
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```c
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static int open_and_attach_perf_event(int freq, struct bpf_program *prog,
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static int open_and_attach_perf_event(int freq, struct bpf_program *prog,
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struct bpf_link *links[])
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struct bpf_link *links[])
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{
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{
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struct perf_event_attr attr = {
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struct perf_event_attr attr = {
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.type = PERF_TYPE_SOFTWARE,
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.type = PERF_TYPE_SOFTWARE,
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.freq = env.freq,
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.freq = env.freq,
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.sample_freq = env.sample_freq,
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.sample_freq = env.sample_freq,
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.config = PERF_COUNT_SW_CPU_CLOCK,
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.config = PERF_COUNT_SW_CPU_CLOCK,
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};
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};
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int i, fd;
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int i, fd;
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for (i = 0; i < nr_cpus; i++) {
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for (i = 0; i < nr_cpus; i++) {
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if (env.cpu != -1 && env.cpu != i)
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if (env.cpu != -1 && env.cpu != i)
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continue;
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continue;
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fd = syscall(__NR_perf_event_open, &attr, -1, i, -1, 0);
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fd = syscall(__NR_perf_event_open, &attr, -1, i, -1, 0);
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if (fd < 0) {
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if (fd < 0) {
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/* Ignore CPU that is offline */
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/* Ignore CPU that is offline */
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if (errno == ENODEV)
|
if (errno == ENODEV)
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continue;
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continue;
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fprintf(stderr, "failed to init perf sampling: %s\n",
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fprintf(stderr, "failed to init perf sampling: %s\n",
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strerror(errno));
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strerror(errno));
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return -1;
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return -1;
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}
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}
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links[i] = bpf_program__attach_perf_event(prog, fd);
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links[i] = bpf_program__attach_perf_event(prog, fd);
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if (!links[i]) {
|
if (!links[i]) {
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fprintf(stderr, "failed to attach perf event on cpu: "
|
fprintf(stderr, "failed to attach perf event on cpu: "
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"%d\n", i);
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"%d\n", i);
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links[i] = NULL;
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links[i] = NULL;
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close(fd);
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close(fd);
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return -1;
|
return -1;
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}
|
}
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}
|
}
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return 0;
|
return 0;
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}
|
}
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```
|
```
|
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|
|
||||||
其ebpf程序实现逻辑是对程序的堆栈进行定时采样，从而捕获程序的执行流程。
|
其ebpf程序实现逻辑是对程序的堆栈进行定时采样，从而捕获程序的执行流程。
|
||||||
|
|
||||||
```c
|
```c
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SEC("perf_event")
|
SEC("perf_event")
|
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int profile(void *ctx)
|
int profile(void *ctx)
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{
|
{
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int pid = bpf_get_current_pid_tgid() >> 32;
|
int pid = bpf_get_current_pid_tgid() >> 32;
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int cpu_id = bpf_get_smp_processor_id();
|
int cpu_id = bpf_get_smp_processor_id();
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struct stacktrace_event *event;
|
struct stacktrace_event *event;
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int cp;
|
int cp;
|
||||||
|
|
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event = bpf_ringbuf_reserve(&events, sizeof(*event), 0);
|
event = bpf_ringbuf_reserve(&events, sizeof(*event), 0);
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if (!event)
|
if (!event)
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return 1;
|
return 1;
|
||||||
|
|
||||||
event->pid = pid;
|
event->pid = pid;
|
||||||
event->cpu_id = cpu_id;
|
event->cpu_id = cpu_id;
|
||||||
|
|
||||||
if (bpf_get_current_comm(event->comm, sizeof(event->comm)))
|
if (bpf_get_current_comm(event->comm, sizeof(event->comm)))
|
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event->comm[0] = 0;
|
event->comm[0] = 0;
|
||||||
|
|
||||||
event->kstack_sz = bpf_get_stack(ctx, event->kstack, sizeof(event->kstack), 0);
|
event->kstack_sz = bpf_get_stack(ctx, event->kstack, sizeof(event->kstack), 0);
|
||||||
|
|
||||||
event->ustack_sz = bpf_get_stack(ctx, event->ustack, sizeof(event->ustack), BPF_F_USER_STACK);
|
event->ustack_sz = bpf_get_stack(ctx, event->ustack, sizeof(event->ustack), BPF_F_USER_STACK);
|
||||||
|
|
||||||
bpf_ringbuf_submit(event, 0);
|
bpf_ringbuf_submit(event, 0);
|
||||||
|
|
||||||
return 0;
|
return 0;
|
||||||
}
|
}
|
||||||
```
|
```
|
||||||
|
|
||||||
通过这种方式，它可以根据用户指令，简单的决定追踪用户态层面的执行流程或是内核态层面的执行流程。
|
通过这种方式，它可以根据用户指令，简单的决定追踪用户态层面的执行流程或是内核态层面的执行流程。
|
||||||
### 编译运行
|
|
||||||
|
## 编译运行
|
||||||
|
|
||||||
```console
|
```console
|
||||||
$ git clone https://github.com/libbpf/libbpf-bootstrap.git --recurse-submodules
|
$ git clone https://github.com/libbpf/libbpf-bootstrap.git --recurse-submodules
|
||||||
$ cd examples/c
|
$ cd examples/c
|
||||||
@@ -105,4 +111,5 @@ Userspace:
|
|||||||
```
|
```
|
||||||
|
|
||||||
### 总结
|
### 总结
|
||||||
|
|
||||||
`profile` 实现了对程序执行流程的分析，在debug等操作中可以极大的帮助开发者提高效率。
|
`profile` 实现了对程序执行流程的分析，在debug等操作中可以极大的帮助开发者提高效率。
|
||||||
|
|||||||
244
src/12-profile/profile.c
Normal file
244
src/12-profile/profile.c
Normal file
@@ -0,0 +1,244 @@
|
|||||||
|
// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
|
||||||
|
/* Copyright (c) 2022 Facebook */
|
||||||
|
#include <stdio.h>
|
||||||
|
#include <unistd.h>
|
||||||
|
#include <string.h>
|
||||||
|
#include <fcntl.h>
|
||||||
|
#include <sys/syscall.h>
|
||||||
|
#include <sys/sysinfo.h>
|
||||||
|
#include <linux/perf_event.h>
|
||||||
|
#include <bpf/libbpf.h>
|
||||||
|
#include <bpf/bpf.h>
|
||||||
|
|
||||||
|
#include "profile.skel.h"
|
||||||
|
#include "profile.h"
|
||||||
|
#include "blazesym.h"
|
||||||
|
|
||||||
|
/*
|
||||||
|
* This function is from libbpf, but it is not a public API and can only be
|
||||||
|
* used for demonstration. We can use this here because we statically link
|
||||||
|
* against the libbpf built from submodule during build.
|
||||||
|
*/
|
||||||
|
extern int parse_cpu_mask_file(const char *fcpu, bool **mask, int *mask_sz);
|
||||||
|
|
||||||
|
static long perf_event_open(struct perf_event_attr *hw_event, pid_t pid,
|
||||||
|
int cpu, int group_fd, unsigned long flags)
|
||||||
|
{
|
||||||
|
int ret;
|
||||||
|
|
||||||
|
ret = syscall(__NR_perf_event_open, hw_event, pid, cpu, group_fd, flags);
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
|
||||||
|
static struct blazesym *symbolizer;
|
||||||
|
|
||||||
|
static void show_stack_trace(__u64 *stack, int stack_sz, pid_t pid)
|
||||||
|
{
|
||||||
|
const struct blazesym_result *result;
|
||||||
|
const struct blazesym_csym *sym;
|
||||||
|
sym_src_cfg src;
|
||||||
|
int i, j;
|
||||||
|
|
||||||
|
if (pid) {
|
||||||
|
src.src_type = SRC_T_PROCESS;
|
||||||
|
src.params.process.pid = pid;
|
||||||
|
} else {
|
||||||
|
src.src_type = SRC_T_KERNEL;
|
||||||
|
src.params.kernel.kallsyms = NULL;
|
||||||
|
src.params.kernel.kernel_image = NULL;
|
||||||
|
}
|
||||||
|
|
||||||
|
result = blazesym_symbolize(symbolizer, &src, 1, (const uint64_t *)stack, stack_sz);
|
||||||
|
|
||||||
|
for (i = 0; i < stack_sz; i++) {
|
||||||
|
if (!result || result->size <= i || !result->entries[i].size) {
|
||||||
|
printf(" %d [<%016llx>]\n", i, stack[i]);
|
||||||
|
continue;
|
||||||
|
}
|
||||||
|
|
||||||
|
if (result->entries[i].size == 1) {
|
||||||
|
sym = &result->entries[i].syms[0];
|
||||||
|
if (sym->path && sym->path[0]) {
|
||||||
|
printf(" %d [<%016llx>] %s+0x%llx %s:%ld\n",
|
||||||
|
i, stack[i], sym->symbol,
|
||||||
|
stack[i] - sym->start_address,
|
||||||
|
sym->path, sym->line_no);
|
||||||
|
} else {
|
||||||
|
printf(" %d [<%016llx>] %s+0x%llx\n",
|
||||||
|
i, stack[i], sym->symbol,
|
||||||
|
stack[i] - sym->start_address);
|
||||||
|
}
|
||||||
|
continue;
|
||||||
|
}
|
||||||
|
|
||||||
|
printf(" %d [<%016llx>]\n", i, stack[i]);
|
||||||
|
for (j = 0; j < result->entries[i].size; j++) {
|
||||||
|
sym = &result->entries[i].syms[j];
|
||||||
|
if (sym->path && sym->path[0]) {
|
||||||
|
printf(" %s+0x%llx %s:%ld\n",
|
||||||
|
sym->symbol, stack[i] - sym->start_address,
|
||||||
|
sym->path, sym->line_no);
|
||||||
|
} else {
|
||||||
|
printf(" %s+0x%llx\n", sym->symbol,
|
||||||
|
stack[i] - sym->start_address);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
blazesym_result_free(result);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Receive events from the ring buffer. */
|
||||||
|
static int event_handler(void *_ctx, void *data, size_t size)
|
||||||
|
{
|
||||||
|
struct stacktrace_event *event = data;
|
||||||
|
|
||||||
|
if (event->kstack_sz <= 0 && event->ustack_sz <= 0)
|
||||||
|
return 1;
|
||||||
|
|
||||||
|
printf("COMM: %s (pid=%d) @ CPU %d\n", event->comm, event->pid, event->cpu_id);
|
||||||
|
|
||||||
|
if (event->kstack_sz > 0) {
|
||||||
|
printf("Kernel:\n");
|
||||||
|
show_stack_trace(event->kstack, event->kstack_sz / sizeof(__u64), 0);
|
||||||
|
} else {
|
||||||
|
printf("No Kernel Stack\n");
|
||||||
|
}
|
||||||
|
|
||||||
|
if (event->ustack_sz > 0) {
|
||||||
|
printf("Userspace:\n");
|
||||||
|
show_stack_trace(event->ustack, event->ustack_sz / sizeof(__u64), event->pid);
|
||||||
|
} else {
|
||||||
|
printf("No Userspace Stack\n");
|
||||||
|
}
|
||||||
|
|
||||||
|
printf("\n");
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
static void show_help(const char *progname)
|
||||||
|
{
|
||||||
|
printf("Usage: %s [-f <frequency>] [-h]\n", progname);
|
||||||
|
}
|
||||||
|
|
||||||
|
int main(int argc, char * const argv[])
|
||||||
|
{
|
||||||
|
const char *online_cpus_file = "/sys/devices/system/cpu/online";
|
||||||
|
int freq = 1, pid = -1, cpu;
|
||||||
|
struct profile_bpf *skel = NULL;
|
||||||
|
struct perf_event_attr attr;
|
||||||
|
struct bpf_link **links = NULL;
|
||||||
|
struct ring_buffer *ring_buf = NULL;
|
||||||
|
int num_cpus, num_online_cpus;
|
||||||
|
int *pefds = NULL, pefd;
|
||||||
|
int argp, i, err = 0;
|
||||||
|
bool *online_mask = NULL;
|
||||||
|
|
||||||
|
while ((argp = getopt(argc, argv, "hf:")) != -1) {
|
||||||
|
switch (argp) {
|
||||||
|
case 'f':
|
||||||
|
freq = atoi(optarg);
|
||||||
|
if (freq < 1)
|
||||||
|
freq = 1;
|
||||||
|
break;
|
||||||
|
|
||||||
|
case 'h':
|
||||||
|
default:
|
||||||
|
show_help(argv[0]);
|
||||||
|
return 1;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
err = parse_cpu_mask_file(online_cpus_file, &online_mask, &num_online_cpus);
|
||||||
|
if (err) {
|
||||||
|
fprintf(stderr, "Fail to get online CPU numbers: %d\n", err);
|
||||||
|
goto cleanup;
|
||||||
|
}
|
||||||
|
|
||||||
|
num_cpus = libbpf_num_possible_cpus();
|
||||||
|
if (num_cpus <= 0) {
|
||||||
|
fprintf(stderr, "Fail to get the number of processors\n");
|
||||||
|
err = -1;
|
||||||
|
goto cleanup;
|
||||||
|
}
|
||||||
|
|
||||||
|
skel = profile_bpf__open_and_load();
|
||||||
|
if (!skel) {
|
||||||
|
fprintf(stderr, "Fail to open and load BPF skeleton\n");
|
||||||
|
err = -1;
|
||||||
|
goto cleanup;
|
||||||
|
}
|
||||||
|
|
||||||
|
symbolizer = blazesym_new();
|
||||||
|
if (!symbolizer) {
|
||||||
|
fprintf(stderr, "Fail to create a symbolizer\n");
|
||||||
|
err = -1;
|
||||||
|
goto cleanup;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Prepare ring buffer to receive events from the BPF program. */
|
||||||
|
ring_buf = ring_buffer__new(bpf_map__fd(skel->maps.events), event_handler, NULL, NULL);
|
||||||
|
if (!ring_buf) {
|
||||||
|
err = -1;
|
||||||
|
goto cleanup;
|
||||||
|
}
|
||||||
|
|
||||||
|
pefds = malloc(num_cpus * sizeof(int));
|
||||||
|
for (i = 0; i < num_cpus; i++) {
|
||||||
|
pefds[i] = -1;
|
||||||
|
}
|
||||||
|
|
||||||
|
links = calloc(num_cpus, sizeof(struct bpf_link *));
|
||||||
|
|
||||||
|
memset(&attr, 0, sizeof(attr));
|
||||||
|
attr.type = PERF_TYPE_HARDWARE;
|
||||||
|
attr.size = sizeof(attr);
|
||||||
|
attr.config = PERF_COUNT_HW_CPU_CYCLES;
|
||||||
|
attr.sample_freq = freq;
|
||||||
|
attr.freq = 1;
|
||||||
|
|
||||||
|
for (cpu = 0; cpu < num_cpus; cpu++) {
|
||||||
|
/* skip offline/not present CPUs */
|
||||||
|
if (cpu >= num_online_cpus || !online_mask[cpu])
|
||||||
|
continue;
|
||||||
|
|
||||||
|
/* Set up performance monitoring on a CPU/Core */
|
||||||
|
pefd = perf_event_open(&attr, pid, cpu, -1, PERF_FLAG_FD_CLOEXEC);
|
||||||
|
if (pefd < 0) {
|
||||||
|
fprintf(stderr, "Fail to set up performance monitor on a CPU/Core\n");
|
||||||
|
err = -1;
|
||||||
|
goto cleanup;
|
||||||
|
}
|
||||||
|
pefds[cpu] = pefd;
|
||||||
|
|
||||||
|
/* Attach a BPF program on a CPU */
|
||||||
|
links[cpu] = bpf_program__attach_perf_event(skel->progs.profile, pefd);
|
||||||
|
if (!links[cpu]) {
|
||||||
|
err = -1;
|
||||||
|
goto cleanup;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Wait and receive stack traces */
|
||||||
|
while (ring_buffer__poll(ring_buf, -1) >= 0) {
|
||||||
|
}
|
||||||
|
|
||||||
|
cleanup:
|
||||||
|
if (links) {
|
||||||
|
for (cpu = 0; cpu < num_cpus; cpu++)
|
||||||
|
bpf_link__destroy(links[cpu]);
|
||||||
|
free(links);
|
||||||
|
}
|
||||||
|
if (pefds) {
|
||||||
|
for (i = 0; i < num_cpus; i++) {
|
||||||
|
if (pefds[i] >= 0)
|
||||||
|
close(pefds[i]);
|
||||||
|
}
|
||||||
|
free(pefds);
|
||||||
|
}
|
||||||
|
ring_buffer__free(ring_buf);
|
||||||
|
profile_bpf__destroy(skel);
|
||||||
|
blazesym_free(symbolizer);
|
||||||
|
free(online_mask);
|
||||||
|
return -err;
|
||||||
|
}
|
||||||
Reference in New Issue
Block a user