selftests/bpf: Add BPF skeletons selftests and convert attach_probe.c

Add BPF skeleton generation to selftest/bpf's Makefile. Convert attach_probe.c
to use skeleton.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191214014341.3442258-15-andriin@fb.com
This commit is contained in:
Andrii Nakryiko 2019-12-13 17:43:38 -08:00 committed by Alexei Starovoitov
parent 985ead416d
commit f3c926a4df
4 changed files with 74 additions and 133 deletions

View File

@ -38,5 +38,7 @@ test_hashmap
test_btf_dump
xdping
test_cpp
*.skel.h
/no_alu32
/bpf_gcc
/tools

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@ -3,10 +3,12 @@ include ../../../../scripts/Kbuild.include
include ../../../scripts/Makefile.arch
CURDIR := $(abspath .)
LIBDIR := $(abspath ../../../lib)
TOOLSDIR := $(abspath ../../..)
LIBDIR := $(TOOLSDIR)/lib
BPFDIR := $(LIBDIR)/bpf
TOOLSDIR := $(abspath ../../../include)
APIDIR := $(TOOLSDIR)/uapi
TOOLSINCDIR := $(TOOLSDIR)/include
BPFTOOLDIR := $(TOOLSDIR)/bpf/bpftool
APIDIR := $(TOOLSINCDIR)/uapi
GENDIR := $(abspath ../../../../include/generated)
GENHDR := $(GENDIR)/autoconf.h
@ -19,7 +21,7 @@ LLC ?= llc
LLVM_OBJCOPY ?= llvm-objcopy
BPF_GCC ?= $(shell command -v bpf-gcc;)
CFLAGS += -g -Wall -O2 $(GENFLAGS) -I$(APIDIR) -I$(LIBDIR) -I$(BPFDIR) \
-I$(GENDIR) -I$(TOOLSDIR) -I$(CURDIR) \
-I$(GENDIR) -I$(TOOLSINCDIR) -I$(CURDIR) \
-Dbpf_prog_load=bpf_prog_test_load \
-Dbpf_load_program=bpf_test_load_program
LDLIBS += -lcap -lelf -lrt -lpthread
@ -117,6 +119,12 @@ $(OUTPUT)/test_cgroup_attach: cgroup_helpers.c
# force a rebuild of BPFOBJ when its dependencies are updated
force:
DEFAULT_BPFTOOL := $(OUTPUT)/tools/usr/local/sbin/bpftool
BPFTOOL ?= $(DEFAULT_BPFTOOL)
$(DEFAULT_BPFTOOL): force
$(MAKE) -C $(BPFTOOLDIR) DESTDIR=$(OUTPUT)/tools install
$(BPFOBJ): force
$(MAKE) -C $(BPFDIR) OUTPUT=$(OUTPUT)/
@ -180,6 +188,8 @@ define GCC_BPF_BUILD_RULE
$(BPF_GCC) $3 $4 -O2 -c $1 -o $2
endef
SKEL_BLACKLIST := btf__% test_pinning_invalid.c
# Set up extra TRUNNER_XXX "temporary" variables in the environment (relies on
# $eval()) and pass control to DEFINE_TEST_RUNNER_RULES.
# Parameters:
@ -195,8 +205,11 @@ TRUNNER_EXTRA_OBJS := $$(patsubst %.c,$$(TRUNNER_OUTPUT)/%.o, \
$$(filter %.c,$(TRUNNER_EXTRA_SOURCES)))
TRUNNER_EXTRA_HDRS := $$(filter %.h,$(TRUNNER_EXTRA_SOURCES))
TRUNNER_TESTS_HDR := $(TRUNNER_TESTS_DIR)/tests.h
TRUNNER_BPF_OBJS := $$(patsubst %.c,$$(TRUNNER_OUTPUT)/%.o, \
$$(notdir $$(wildcard $(TRUNNER_BPF_PROGS_DIR)/*.c)))
TRUNNER_BPF_SRCS := $$(notdir $$(wildcard $(TRUNNER_BPF_PROGS_DIR)/*.c))
TRUNNER_BPF_OBJS := $$(patsubst %.c,$$(TRUNNER_OUTPUT)/%.o, $$(TRUNNER_BPF_SRCS))
TRUNNER_BPF_SKELS := $$(patsubst %.c,$$(TRUNNER_OUTPUT)/%.skel.h, \
$$(filter-out $(SKEL_BLACKLIST), \
$$(TRUNNER_BPF_SRCS)))
# Evaluate rules now with extra TRUNNER_XXX variables above already defined
$$(eval $$(call DEFINE_TEST_RUNNER_RULES,$1,$2))
@ -226,6 +239,11 @@ $(TRUNNER_BPF_OBJS): $(TRUNNER_OUTPUT)/%.o: \
$$(call $(TRUNNER_BPF_BUILD_RULE),$$<,$$@, \
$(TRUNNER_BPF_CFLAGS), \
$(TRUNNER_BPF_LDFLAGS))
$(TRUNNER_BPF_SKELS): $(TRUNNER_OUTPUT)/%.skel.h: \
$(TRUNNER_OUTPUT)/%.o \
| $(BPFTOOL) $(TRUNNER_OUTPUT)
$$(BPFTOOL) gen skeleton $$< > $$@
endif
# ensure we set up tests.h header generation rule just once
@ -245,6 +263,7 @@ $(TRUNNER_TEST_OBJS): $(TRUNNER_OUTPUT)/%.test.o: \
$(TRUNNER_TESTS_DIR)/%.c \
$(TRUNNER_EXTRA_HDRS) \
$(TRUNNER_BPF_OBJS) \
$(TRUNNER_BPF_SKELS) \
$$(BPFOBJ) | $(TRUNNER_OUTPUT)
cd $$(@D) && $$(CC) $$(CFLAGS) -c $(CURDIR)/$$< $$(LDLIBS) -o $$(@F)
@ -255,9 +274,9 @@ $(TRUNNER_EXTRA_OBJS): $(TRUNNER_OUTPUT)/%.o: \
$$(BPFOBJ) | $(TRUNNER_OUTPUT)
$$(CC) $$(CFLAGS) -c $$< $$(LDLIBS) -o $$@
# only copy extra resources if in flavored build
$(TRUNNER_BINARY)-extras: $(TRUNNER_EXTRA_FILES) | $(TRUNNER_OUTPUT)
ifneq ($2,)
# only copy extra resources if in flavored build
cp -a $$^ $(TRUNNER_OUTPUT)/
endif
@ -323,4 +342,5 @@ $(OUTPUT)/test_cpp: test_cpp.cpp $(BPFOBJ)
EXTRA_CLEAN := $(TEST_CUSTOM_PROGS) \
prog_tests/tests.h map_tests/tests.h verifier/tests.h \
feature $(OUTPUT)/*.o $(OUTPUT)/no_alu32 $(OUTPUT)/bpf_gcc
feature $(OUTPUT)/*.o $(OUTPUT)/no_alu32 $(OUTPUT)/bpf_gcc \
tools *.skel.h

View File

@ -1,5 +1,6 @@
// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>
#include "test_attach_probe.skel.h"
ssize_t get_base_addr() {
size_t start;
@ -25,26 +26,10 @@ BPF_EMBED_OBJ(probe, "test_attach_probe.o");
void test_attach_probe(void)
{
const char *kprobe_name = "kprobe/sys_nanosleep";
const char *kretprobe_name = "kretprobe/sys_nanosleep";
const char *uprobe_name = "uprobe/trigger_func";
const char *uretprobe_name = "uretprobe/trigger_func";
const int kprobe_idx = 0, kretprobe_idx = 1;
const int uprobe_idx = 2, uretprobe_idx = 3;
const char *obj_name = "attach_probe";
DECLARE_LIBBPF_OPTS(bpf_object_open_opts, open_opts,
.object_name = obj_name,
.relaxed_maps = true,
);
struct bpf_program *kprobe_prog, *kretprobe_prog;
struct bpf_program *uprobe_prog, *uretprobe_prog;
struct bpf_object *obj;
int err, duration = 0, res;
struct bpf_link *kprobe_link = NULL;
struct bpf_link *kretprobe_link = NULL;
struct bpf_link *uprobe_link = NULL;
struct bpf_link *uretprobe_link = NULL;
int results_map_fd;
int duration = 0;
struct bpf_link *kprobe_link, *kretprobe_link;
struct bpf_link *uprobe_link, *uretprobe_link;
struct test_attach_probe* skel;
size_t uprobe_offset;
ssize_t base_addr;
@ -54,124 +39,68 @@ void test_attach_probe(void)
return;
uprobe_offset = (size_t)&get_base_addr - base_addr;
/* open object */
obj = bpf_object__open_mem(probe_embed.data, probe_embed.size,
&open_opts);
if (CHECK(IS_ERR(obj), "obj_open_mem", "err %ld\n", PTR_ERR(obj)))
skel = test_attach_probe__open_and_load(&probe_embed);
if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))
return;
if (CHECK(strcmp(bpf_object__name(obj), obj_name), "obj_name",
"wrong obj name '%s', expected '%s'\n",
bpf_object__name(obj), obj_name))
if (CHECK(!skel->bss, "check_bss", ".bss wasn't mmap()-ed\n"))
goto cleanup;
kprobe_prog = bpf_object__find_program_by_title(obj, kprobe_name);
if (CHECK(!kprobe_prog, "find_probe",
"prog '%s' not found\n", kprobe_name))
goto cleanup;
kretprobe_prog = bpf_object__find_program_by_title(obj, kretprobe_name);
if (CHECK(!kretprobe_prog, "find_probe",
"prog '%s' not found\n", kretprobe_name))
goto cleanup;
uprobe_prog = bpf_object__find_program_by_title(obj, uprobe_name);
if (CHECK(!uprobe_prog, "find_probe",
"prog '%s' not found\n", uprobe_name))
goto cleanup;
uretprobe_prog = bpf_object__find_program_by_title(obj, uretprobe_name);
if (CHECK(!uretprobe_prog, "find_probe",
"prog '%s' not found\n", uretprobe_name))
goto cleanup;
/* create maps && load programs */
err = bpf_object__load(obj);
if (CHECK(err, "obj_load", "err %d\n", err))
goto cleanup;
/* load maps */
results_map_fd = bpf_find_map(__func__, obj, "results_map");
if (CHECK(results_map_fd < 0, "find_results_map",
"err %d\n", results_map_fd))
goto cleanup;
kprobe_link = bpf_program__attach_kprobe(kprobe_prog,
kprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kprobe,
false /* retprobe */,
SYS_NANOSLEEP_KPROBE_NAME);
if (CHECK(IS_ERR(kprobe_link), "attach_kprobe",
"err %ld\n", PTR_ERR(kprobe_link))) {
kprobe_link = NULL;
"err %ld\n", PTR_ERR(kprobe_link)))
goto cleanup;
}
kretprobe_link = bpf_program__attach_kprobe(kretprobe_prog,
skel->links.handle_kprobe = kprobe_link;
kretprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kretprobe,
true /* retprobe */,
SYS_NANOSLEEP_KPROBE_NAME);
if (CHECK(IS_ERR(kretprobe_link), "attach_kretprobe",
"err %ld\n", PTR_ERR(kretprobe_link))) {
kretprobe_link = NULL;
"err %ld\n", PTR_ERR(kretprobe_link)))
goto cleanup;
}
uprobe_link = bpf_program__attach_uprobe(uprobe_prog,
skel->links.handle_kretprobe = kretprobe_link;
uprobe_link = bpf_program__attach_uprobe(skel->progs.handle_uprobe,
false /* retprobe */,
0 /* self pid */,
"/proc/self/exe",
uprobe_offset);
if (CHECK(IS_ERR(uprobe_link), "attach_uprobe",
"err %ld\n", PTR_ERR(uprobe_link))) {
uprobe_link = NULL;
"err %ld\n", PTR_ERR(uprobe_link)))
goto cleanup;
}
uretprobe_link = bpf_program__attach_uprobe(uretprobe_prog,
skel->links.handle_uprobe = uprobe_link;
uretprobe_link = bpf_program__attach_uprobe(skel->progs.handle_uretprobe,
true /* retprobe */,
-1 /* any pid */,
"/proc/self/exe",
uprobe_offset);
if (CHECK(IS_ERR(uretprobe_link), "attach_uretprobe",
"err %ld\n", PTR_ERR(uretprobe_link))) {
uretprobe_link = NULL;
"err %ld\n", PTR_ERR(uretprobe_link)))
goto cleanup;
}
skel->links.handle_uretprobe = uretprobe_link;
/* trigger & validate kprobe && kretprobe */
usleep(1);
err = bpf_map_lookup_elem(results_map_fd, &kprobe_idx, &res);
if (CHECK(err, "get_kprobe_res",
"failed to get kprobe res: %d\n", err))
if (CHECK(skel->bss->kprobe_res != 1, "check_kprobe_res",
"wrong kprobe res: %d\n", skel->bss->kprobe_res))
goto cleanup;
if (CHECK(res != kprobe_idx + 1, "check_kprobe_res",
"wrong kprobe res: %d\n", res))
goto cleanup;
err = bpf_map_lookup_elem(results_map_fd, &kretprobe_idx, &res);
if (CHECK(err, "get_kretprobe_res",
"failed to get kretprobe res: %d\n", err))
goto cleanup;
if (CHECK(res != kretprobe_idx + 1, "check_kretprobe_res",
"wrong kretprobe res: %d\n", res))
if (CHECK(skel->bss->kretprobe_res != 2, "check_kretprobe_res",
"wrong kretprobe res: %d\n", skel->bss->kretprobe_res))
goto cleanup;
/* trigger & validate uprobe & uretprobe */
get_base_addr();
err = bpf_map_lookup_elem(results_map_fd, &uprobe_idx, &res);
if (CHECK(err, "get_uprobe_res",
"failed to get uprobe res: %d\n", err))
if (CHECK(skel->bss->uprobe_res != 3, "check_uprobe_res",
"wrong uprobe res: %d\n", skel->bss->uprobe_res))
goto cleanup;
if (CHECK(res != uprobe_idx + 1, "check_uprobe_res",
"wrong uprobe res: %d\n", res))
goto cleanup;
err = bpf_map_lookup_elem(results_map_fd, &uretprobe_idx, &res);
if (CHECK(err, "get_uretprobe_res",
"failed to get uretprobe res: %d\n", err))
goto cleanup;
if (CHECK(res != uretprobe_idx + 1, "check_uretprobe_res",
"wrong uretprobe res: %d\n", res))
if (CHECK(skel->bss->uretprobe_res != 4, "check_uretprobe_res",
"wrong uretprobe res: %d\n", skel->bss->uretprobe_res))
goto cleanup;
cleanup:
bpf_link__destroy(kprobe_link);
bpf_link__destroy(kretprobe_link);
bpf_link__destroy(uprobe_link);
bpf_link__destroy(uretprobe_link);
bpf_object__close(obj);
test_attach_probe__destroy(skel);
}

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@ -5,46 +5,36 @@
#include <linux/bpf.h>
#include "bpf_helpers.h"
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 4);
__type(key, int);
__type(value, int);
} results_map SEC(".maps");
int kprobe_res = 0;
int kretprobe_res = 0;
int uprobe_res = 0;
int uretprobe_res = 0;
SEC("kprobe/sys_nanosleep")
int handle_sys_nanosleep_entry(struct pt_regs *ctx)
int handle_kprobe(struct pt_regs *ctx)
{
const int key = 0, value = 1;
bpf_map_update_elem(&results_map, &key, &value, 0);
kprobe_res = 1;
return 0;
}
SEC("kretprobe/sys_nanosleep")
int handle_sys_getpid_return(struct pt_regs *ctx)
int handle_kretprobe(struct pt_regs *ctx)
{
const int key = 1, value = 2;
bpf_map_update_elem(&results_map, &key, &value, 0);
kretprobe_res = 2;
return 0;
}
SEC("uprobe/trigger_func")
int handle_uprobe_entry(struct pt_regs *ctx)
int handle_uprobe(struct pt_regs *ctx)
{
const int key = 2, value = 3;
bpf_map_update_elem(&results_map, &key, &value, 0);
uprobe_res = 3;
return 0;
}
SEC("uretprobe/trigger_func")
int handle_uprobe_return(struct pt_regs *ctx)
int handle_uretprobe(struct pt_regs *ctx)
{
const int key = 3, value = 4;
bpf_map_update_elem(&results_map, &key, &value, 0);
uretprobe_res = 4;
return 0;
}