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This commit is contained in:
yunwei37
2023-05-06 19:59:08 +00:00
parent e10d1a77f1
commit 981d1333f6
22 changed files with 663 additions and 744 deletions
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3
14-tcpstates/.gitignore vendored
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@@ -2,4 +2,5 @@
package.json
eunomia-exporter
ecli
tcpstates
.output

141
14-tcpstates/Makefile Normal file
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@@ -0,0 +1,141 @@
# SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
OUTPUT := .output
CLANG ?= clang
LIBBPF_SRC := $(abspath ../../libbpf/src)
BPFTOOL_SRC := $(abspath ../../bpftool/src)
LIBBPF_OBJ := $(abspath $(OUTPUT)/libbpf.a)
BPFTOOL_OUTPUT ?= $(abspath $(OUTPUT)/bpftool)
BPFTOOL ?= $(BPFTOOL_OUTPUT)/bootstrap/bpftool
LIBBLAZESYM_SRC := $(abspath ../../blazesym/)
LIBBLAZESYM_OBJ := $(abspath $(OUTPUT)/libblazesym.a)
LIBBLAZESYM_HEADER := $(abspath $(OUTPUT)/blazesym.h)
ARCH ?= $(shell uname -m | sed 's/x86_64/x86/' \
| sed 's/arm.*/arm/' \
| sed 's/aarch64/arm64/' \
| sed 's/ppc64le/powerpc/' \
| sed 's/mips.*/mips/' \
| sed 's/riscv64/riscv/' \
| sed 's/loongarch64/loongarch/')
VMLINUX := ../../vmlinux/$(ARCH)/vmlinux.h
# Use our own libbpf API headers and Linux UAPI headers distributed with
# libbpf to avoid dependency on system-wide headers, which could be missing or
# outdated
INCLUDES := -I$(OUTPUT) -I../../libbpf/include/uapi -I$(dir $(VMLINUX))
CFLAGS := -g -Wall
ALL_LDFLAGS := $(LDFLAGS) $(EXTRA_LDFLAGS)
APPS = tcpstates # minimal minimal_legacy uprobe kprobe fentry usdt sockfilter tc ksyscall
CARGO ?= $(shell which cargo)
ifeq ($(strip $(CARGO)),)
BZS_APPS :=
else
BZS_APPS := # profile
APPS += $(BZS_APPS)
# Required by libblazesym
ALL_LDFLAGS += -lrt -ldl -lpthread -lm
endif
# Get Clang's default includes on this system. We'll explicitly add these dirs
# to the includes list when compiling with `-target bpf` because otherwise some
# architecture-specific dirs will be "missing" on some architectures/distros -
# headers such as asm/types.h, asm/byteorder.h, asm/socket.h, asm/sockios.h,
# sys/cdefs.h etc. might be missing.
#
# Use '-idirafter': Don't interfere with include mechanics except where the
# build would have failed anyways.
CLANG_BPF_SYS_INCLUDES ?= $(shell $(CLANG) -v -E - </dev/null 2>&1 \
| sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }')
ifeq ($(V),1)
Q =
msg =
else
Q = @
msg = @printf ' %-8s %s%s\n' \
"$(1)" \
"$(patsubst $(abspath $(OUTPUT))/%,%,$(2))" \
"$(if $(3), $(3))";
MAKEFLAGS += --no-print-directory
endif
define allow-override
$(if $(or $(findstring environment,$(origin $(1))),\
$(findstring command line,$(origin $(1)))),,\
$(eval $(1) = $(2)))
endef
$(call allow-override,CC,$(CROSS_COMPILE)cc)
$(call allow-override,LD,$(CROSS_COMPILE)ld)
.PHONY: all
all: $(APPS)
.PHONY: clean
clean:
$(call msg,CLEAN)
$(Q)rm -rf $(OUTPUT) $(APPS)
$(OUTPUT) $(OUTPUT)/libbpf $(BPFTOOL_OUTPUT):
$(call msg,MKDIR,$@)
$(Q)mkdir -p $@
# Build libbpf
$(LIBBPF_OBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(OUTPUT)/libbpf
$(call msg,LIB,$@)
$(Q)$(MAKE) -C $(LIBBPF_SRC) BUILD_STATIC_ONLY=1 \
OBJDIR=$(dir $@)/libbpf DESTDIR=$(dir $@) \
INCLUDEDIR= LIBDIR= UAPIDIR= \
install
# Build bpftool
$(BPFTOOL): | $(BPFTOOL_OUTPUT)
$(call msg,BPFTOOL,$@)
$(Q)$(MAKE) ARCH= CROSS_COMPILE= OUTPUT=$(BPFTOOL_OUTPUT)/ -C $(BPFTOOL_SRC) bootstrap
$(LIBBLAZESYM_SRC)/target/release/libblazesym.a::
$(Q)cd $(LIBBLAZESYM_SRC) && $(CARGO) build --features=cheader,dont-generate-test-files --release
$(LIBBLAZESYM_OBJ): $(LIBBLAZESYM_SRC)/target/release/libblazesym.a | $(OUTPUT)
$(call msg,LIB, $@)
$(Q)cp $(LIBBLAZESYM_SRC)/target/release/libblazesym.a $@
$(LIBBLAZESYM_HEADER): $(LIBBLAZESYM_SRC)/target/release/libblazesym.a | $(OUTPUT)
$(call msg,LIB,$@)
$(Q)cp $(LIBBLAZESYM_SRC)/target/release/blazesym.h $@
# Build BPF code
$(OUTPUT)/%.bpf.o: %.bpf.c $(LIBBPF_OBJ) $(wildcard %.h) $(VMLINUX) | $(OUTPUT) $(BPFTOOL)
$(call msg,BPF,$@)
$(Q)$(CLANG) -g -O2 -target bpf -D__TARGET_ARCH_$(ARCH) \
$(INCLUDES) $(CLANG_BPF_SYS_INCLUDES) \
-c $(filter %.c,$^) -o $(patsubst %.bpf.o,%.tmp.bpf.o,$@)
$(Q)$(BPFTOOL) gen object $@ $(patsubst %.bpf.o,%.tmp.bpf.o,$@)
# Generate BPF skeletons
$(OUTPUT)/%.skel.h: $(OUTPUT)/%.bpf.o | $(OUTPUT) $(BPFTOOL)
$(call msg,GEN-SKEL,$@)
$(Q)$(BPFTOOL) gen skeleton $< > $@
# Build user-space code
$(patsubst %,$(OUTPUT)/%.o,$(APPS)): %.o: %.skel.h
$(OUTPUT)/%.o: %.c $(wildcard %.h) | $(OUTPUT)
$(call msg,CC,$@)
$(Q)$(CC) $(CFLAGS) $(INCLUDES) -c $(filter %.c,$^) -o $@
$(patsubst %,$(OUTPUT)/%.o,$(BZS_APPS)): $(LIBBLAZESYM_HEADER)
$(BZS_APPS): $(LIBBLAZESYM_OBJ)
# Build application binary
$(APPS): %: $(OUTPUT)/%.o $(LIBBPF_OBJ) | $(OUTPUT)
$(call msg,BINARY,$@)
$(Q)$(CC) $(CFLAGS) $^ $(ALL_LDFLAGS) -lelf -lz -o $@
# delete failed targets
.DELETE_ON_ERROR:
# keep intermediate (.skel.h, .bpf.o, etc) targets
.SECONDARY:

121
14-tcpstates/index.html
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@@ -145,6 +145,110 @@
<div id="content" class="content">
<main>
<h1 id="ebpf入门实践教程使用-libbpf-bootstrap-开发程序统计-tcp-连接延时"><a class="header" href="#ebpf入门实践教程使用-libbpf-bootstrap-开发程序统计-tcp-连接延时">eBPF入门实践教程：使用 libbpf-bootstrap 开发程序统计 TCP 连接延时</a></h1>
<h2 id="内核态代码"><a class="header" href="#内核态代码">内核态代码</a></h2>
<pre><code class="language-c">// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
/* Copyright (c) 2021 Hengqi Chen */
#include &lt;vmlinux.h&gt;
#include &lt;bpf/bpf_helpers.h&gt;
#include &lt;bpf/bpf_tracing.h&gt;
#include &lt;bpf/bpf_core_read.h&gt;
#include &quot;tcpstates.h&quot;
#define MAX_ENTRIES 10240
#define AF_INET 2
#define AF_INET6 10
const volatile bool filter_by_sport = false;
const volatile bool filter_by_dport = false;
const volatile short target_family = 0;
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, MAX_ENTRIES);
__type(key, __u16);
__type(value, __u16);
} sports SEC(&quot;.maps&quot;);
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, MAX_ENTRIES);
__type(key, __u16);
__type(value, __u16);
} dports SEC(&quot;.maps&quot;);
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, MAX_ENTRIES);
__type(key, struct sock *);
__type(value, __u64);
} timestamps SEC(&quot;.maps&quot;);
struct {
__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
__uint(key_size, sizeof(__u32));
__uint(value_size, sizeof(__u32));
} events SEC(&quot;.maps&quot;);
SEC(&quot;tracepoint/sock/inet_sock_set_state&quot;)
int handle_set_state(struct trace_event_raw_inet_sock_set_state *ctx)
{
struct sock *sk = (struct sock *)ctx-&gt;skaddr;
__u16 family = ctx-&gt;family;
__u16 sport = ctx-&gt;sport;
__u16 dport = ctx-&gt;dport;
__u64 *tsp, delta_us, ts;
struct event event = {};
if (ctx-&gt;protocol != IPPROTO_TCP)
return 0;
if (target_family &amp;&amp; target_family != family)
return 0;
if (filter_by_sport &amp;&amp; !bpf_map_lookup_elem(&amp;sports, &amp;sport))
return 0;
if (filter_by_dport &amp;&amp; !bpf_map_lookup_elem(&amp;dports, &amp;dport))
return 0;
tsp = bpf_map_lookup_elem(&amp;timestamps, &amp;sk);
ts = bpf_ktime_get_ns();
if (!tsp)
delta_us = 0;
else
delta_us = (ts - *tsp) / 1000;
event.skaddr = (__u64)sk;
event.ts_us = ts / 1000;
event.delta_us = delta_us;
event.pid = bpf_get_current_pid_tgid() &gt;&gt; 32;
event.oldstate = ctx-&gt;oldstate;
event.newstate = ctx-&gt;newstate;
event.family = family;
event.sport = sport;
event.dport = dport;
bpf_get_current_comm(&amp;event.task, sizeof(event.task));
if (family == AF_INET) {
bpf_probe_read_kernel(&amp;event.saddr, sizeof(event.saddr), &amp;sk-&gt;__sk_common.skc_rcv_saddr);
bpf_probe_read_kernel(&amp;event.daddr, sizeof(event.daddr), &amp;sk-&gt;__sk_common.skc_daddr);
} else { /* family == AF_INET6 */
bpf_probe_read_kernel(&amp;event.saddr, sizeof(event.saddr), &amp;sk-&gt;__sk_common.skc_v6_rcv_saddr.in6_u.u6_addr32);
bpf_probe_read_kernel(&amp;event.daddr, sizeof(event.daddr), &amp;sk-&gt;__sk_common.skc_v6_daddr.in6_u.u6_addr32);
}
bpf_perf_event_output(ctx, &amp;events, BPF_F_CURRENT_CPU, &amp;event, sizeof(event));
if (ctx-&gt;newstate == TCP_CLOSE)
bpf_map_delete_elem(&amp;timestamps, &amp;sk);
else
bpf_map_update_elem(&amp;timestamps, &amp;sk, &amp;ts, BPF_ANY);
return 0;
}
char LICENSE[] SEC(&quot;license&quot;) = &quot;Dual BSD/GPL&quot;;
</code></pre>
<p><code>tcpstates</code> 是一个追踪当前系统上的TCP套接字的TCP状态的程序，主要通过跟踪内核跟踪点 <code>inet_sock_set_state</code> 来实现。统计数据通过 <code>perf_event</code>向用户态传输。</p>
<pre><code class="language-c">SEC(&quot;tracepoint/sock/inet_sock_set_state&quot;)
int handle_set_state(struct trace_event_raw_inet_sock_set_state *ctx)
@@ -253,15 +357,13 @@ static void handle_lost_events(void* ctx, int cpu, __u64 lost_cnt) {
</code></pre>
<p>收到事件后所调用对应的处理函数并进行输出打印。</p>
<h2 id="编译运行"><a class="header" href="#编译运行">编译运行</a></h2>
<ul>
<li><code>git clone https://github.com/libbpf/libbpf-bootstrap libbpf-bootstrap-cloned</code></li>
<li>将 <a href="libbpf-bootstrap">libbpf-bootstrap</a>目录下的文件复制到 <code>libbpf-bootstrap-cloned/examples/c</code>下</li>
<li>修改 <code>libbpf-bootstrap-cloned/examples/c/Makefile</code> ，在其 <code>APPS</code> 项后添加 <code>tcpstates</code></li>
<li>在 <code>libbpf-bootstrap-cloned/examples/c</code> 下运行 <code>make tcpstates</code></li>
<li><code>sudo ./tcpstates</code></li>
</ul>
<h2 id="效果"><a class="header" href="#效果">效果</a></h2>
<pre><code class="language-plain">root@yutong-VirtualBox:~/libbpf-bootstrap/examples/c# ./tcpstates
<pre><code class="language-console">$ make
...
BPF .output/tcpstates.bpf.o
GEN-SKEL .output/tcpstates.skel.h
CC .output/tcpstates.o
BINARY tcpstates
$ sudo ./tcpstates
SKADDR PID COMM LADDR LPORT RADDR RPORT OLDSTATE -&gt; NEWSTATE MS
ffff9bf61bb62bc0 164978 node 192.168.88.15 0 52.178.17.2 443 CLOSE -&gt; SYN_SENT 0.000
ffff9bf61bb62bc0 0 swapper/0 192.168.88.15 41596 52.178.17.2 443 SYN_SENT -&gt; ESTABLISHED 225.794
@@ -273,7 +375,6 @@ ffff9bf6d8ee88c0 229832 redis-serv 0.0.0.0 6379 0.0.0.0 0
ffff9bf6d8ee88c0 229832 redis-serv 0.0.0.0 6379 0.0.0.0 0 LISTEN -&gt; CLOSE 1.763
ffff9bf7109d6900 88750 node 127.0.0.1 39755 127.0.0.1 50966 ESTABLISHED -&gt; FIN_WAIT1 0.000
</code></pre>
<p>对于输出的详细解释，详见 <a href="README.html">README.md</a></p>
<h2 id="总结"><a class="header" href="#总结">总结</a></h2>
<p>这里的代码修改自 <a href="https://github.com/iovisor/bcc/blob/master/libbpf-tools/tcpstates.bpf.c">https://github.com/iovisor/bcc/blob/master/libbpf-tools/tcpstates.bpf.c</a></p>

102
14-tcpstates/libbpf-bootstrap/tcpstates.bpf.c
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@@ -1,102 +0,0 @@
// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
/* Copyright (c) 2021 Hengqi Chen */
#include <vmlinux.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#include <bpf/bpf_core_read.h>
#include "tcpstates.h"
#define MAX_ENTRIES 10240
#define AF_INET 2
#define AF_INET6 10
const volatile bool filter_by_sport = false;
const volatile bool filter_by_dport = false;
const volatile short target_family = 0;
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, MAX_ENTRIES);
__type(key, __u16);
__type(value, __u16);
} sports SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, MAX_ENTRIES);
__type(key, __u16);
__type(value, __u16);
} dports SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, MAX_ENTRIES);
__type(key, struct sock *);
__type(value, __u64);
} timestamps SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
__uint(key_size, sizeof(__u32));
__uint(value_size, sizeof(__u32));
} events SEC(".maps");
SEC("tracepoint/sock/inet_sock_set_state")
int handle_set_state(struct trace_event_raw_inet_sock_set_state *ctx)
{
struct sock *sk = (struct sock *)ctx->skaddr;
__u16 family = ctx->family;
__u16 sport = ctx->sport;
__u16 dport = ctx->dport;
__u64 *tsp, delta_us, ts;
struct event event = {};
if (ctx->protocol != IPPROTO_TCP)
return 0;
if (target_family && target_family != family)
return 0;
if (filter_by_sport && !bpf_map_lookup_elem(&sports, &sport))
return 0;
if (filter_by_dport && !bpf_map_lookup_elem(&dports, &dport))
return 0;
tsp = bpf_map_lookup_elem(&timestamps, &sk);
ts = bpf_ktime_get_ns();
if (!tsp)
delta_us = 0;
else
delta_us = (ts - *tsp) / 1000;
event.skaddr = (__u64)sk;
event.ts_us = ts / 1000;
event.delta_us = delta_us;
event.pid = bpf_get_current_pid_tgid() >> 32;
event.oldstate = ctx->oldstate;
event.newstate = ctx->newstate;
event.family = family;
event.sport = sport;
event.dport = dport;
bpf_get_current_comm(&event.task, sizeof(event.task));
if (family == AF_INET) {
bpf_probe_read_kernel(&event.saddr, sizeof(event.saddr), &sk->__sk_common.skc_rcv_saddr);
bpf_probe_read_kernel(&event.daddr, sizeof(event.daddr), &sk->__sk_common.skc_daddr);
} else { /* family == AF_INET6 */
bpf_probe_read_kernel(&event.saddr, sizeof(event.saddr), &sk->__sk_common.skc_v6_rcv_saddr.in6_u.u6_addr32);
bpf_probe_read_kernel(&event.daddr, sizeof(event.daddr), &sk->__sk_common.skc_v6_daddr.in6_u.u6_addr32);
}
bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, &event, sizeof(event));
if (ctx->newstate == TCP_CLOSE)
bpf_map_delete_elem(&timestamps, &sk);
else
bpf_map_update_elem(&timestamps, &sk, &ts, BPF_ANY);
return 0;
}
char LICENSE[] SEC("license") = "Dual BSD/GPL";

27
14-tcpstates/tcpstates.bpf.c
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@@ -4,42 +4,38 @@
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#include <bpf/bpf_core_read.h>
#include "tcpstates.bpf.h"
#include "tcpstates.h"
#define MAX_ENTRIES 10240
#define AF_INET 2
#define AF_INET6 10
#define MAX_ENTRIES 10240
#define AF_INET 2
#define AF_INET6 10
const volatile bool filter_by_sport = false;
const volatile bool filter_by_dport = false;
const volatile short target_family = 0;
struct
{
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, MAX_ENTRIES);
__type(key, __u16);
__type(value, __u16);
} sports SEC(".maps");
struct
{
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, MAX_ENTRIES);
__type(key, __u16);
__type(value, __u16);
} dports SEC(".maps");
struct
{
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, MAX_ENTRIES);
__type(key, struct sock *);
__type(value, __u64);
} timestamps SEC(".maps");
struct
{
struct {
__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
__uint(key_size, sizeof(__u32));
__uint(value_size, sizeof(__u32));
@@ -85,13 +81,10 @@ int handle_set_state(struct trace_event_raw_inet_sock_set_state *ctx)
event.dport = dport;
bpf_get_current_comm(&event.task, sizeof(event.task));
if (family == AF_INET)
{
if (family == AF_INET) {
bpf_probe_read_kernel(&event.saddr, sizeof(event.saddr), &sk->__sk_common.skc_rcv_saddr);
bpf_probe_read_kernel(&event.daddr, sizeof(event.daddr), &sk->__sk_common.skc_daddr);
}
else
{ /* family == AF_INET6 */
} else { /* family == AF_INET6 */
bpf_probe_read_kernel(&event.saddr, sizeof(event.saddr), &sk->__sk_common.skc_v6_rcv_saddr.in6_u.u6_addr32);
bpf_probe_read_kernel(&event.daddr, sizeof(event.daddr), &sk->__sk_common.skc_v6_daddr.in6_u.u6_addr32);
}

24
14-tcpstates/tcpstates.bpf.h
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@@ -1,24 +0,0 @@
// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
/* Copyright (c) 2021 Hengqi Chen */
#ifndef __TCPSTATES_H
#define __TCPSTATES_H
#define TASK_COMM_LEN 16
struct event
{
unsigned __int128 saddr;
unsigned __int128 daddr;
__u64 skaddr;
__u64 ts_us;
__u64 delta_us;
__u32 pid;
int oldstate;
int newstate;
__u16 family;
__u16 sport;
__u16 dport;
char task[TASK_COMM_LEN];
};
#endif /* __TCPSTATES_H */

0
14-tcpstates/libbpf-bootstrap/tcpstates.c → 14-tcpstates/tcpstates.c
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0
14-tcpstates/libbpf-bootstrap/tcpstates.h → 14-tcpstates/tcpstates.h
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