From 3cccbaa0332169d4ff05587062a7ed528aeddb60 Mon Sep 17 00:00:00 2001 From: Delyan Kratunov Date: Wed, 16 Mar 2022 23:37:31 +0000 Subject: [PATCH] selftests/bpf: Test subskeleton functionality This patch changes the selftests/bpf Makefile to also generate a subskel.h for every skel.h it would have normally generated. Separately, it also introduces a new subskeleton test which tests library objects, externs, weak symbols, kconfigs, and user maps. Signed-off-by: Delyan Kratunov Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/1bd24956940bbbfe169bb34f7f87b11df52ef011.1647473511.git.delyank@fb.com --- tools/testing/selftests/bpf/.gitignore | 1 + tools/testing/selftests/bpf/Makefile | 12 ++- .../selftests/bpf/prog_tests/subskeleton.c | 78 +++++++++++++++++++ .../selftests/bpf/progs/test_subskeleton.c | 28 +++++++ .../bpf/progs/test_subskeleton_lib.c | 61 +++++++++++++++ .../bpf/progs/test_subskeleton_lib2.c | 16 ++++ 6 files changed, 194 insertions(+), 2 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/subskeleton.c create mode 100644 tools/testing/selftests/bpf/progs/test_subskeleton.c create mode 100644 tools/testing/selftests/bpf/progs/test_subskeleton_lib.c create mode 100644 tools/testing/selftests/bpf/progs/test_subskeleton_lib2.c diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore index a7eead8820a0..595565eb68c0 100644 --- a/tools/testing/selftests/bpf/.gitignore +++ b/tools/testing/selftests/bpf/.gitignore @@ -31,6 +31,7 @@ test_tcp_check_syncookie_user test_sysctl xdping test_cpp +*.subskel.h *.skel.h *.lskel.h /no_alu32 diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 11f5883636c3..3820608faf57 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -327,7 +327,13 @@ endef SKEL_BLACKLIST := btf__% test_pinning_invalid.c test_sk_assign.c LINKED_SKELS := test_static_linked.skel.h linked_funcs.skel.h \ - linked_vars.skel.h linked_maps.skel.h + linked_vars.skel.h linked_maps.skel.h \ + test_subskeleton.skel.h test_subskeleton_lib.skel.h + +# In the subskeleton case, we want the test_subskeleton_lib.subskel.h file +# but that's created as a side-effect of the skel.h generation. +test_subskeleton.skel.h-deps := test_subskeleton_lib2.o test_subskeleton_lib.o test_subskeleton.o +test_subskeleton_lib.skel.h-deps := test_subskeleton_lib2.o test_subskeleton_lib.o LSKELS := kfunc_call_test.c fentry_test.c fexit_test.c fexit_sleep.c \ test_ringbuf.c atomics.c trace_printk.c trace_vprintk.c \ @@ -405,6 +411,7 @@ $(TRUNNER_BPF_SKELS): %.skel.h: %.o $(BPFTOOL) | $(TRUNNER_OUTPUT) $(Q)$$(BPFTOOL) gen object $$(<:.o=.linked3.o) $$(<:.o=.linked2.o) $(Q)diff $$(<:.o=.linked2.o) $$(<:.o=.linked3.o) $(Q)$$(BPFTOOL) gen skeleton $$(<:.o=.linked3.o) name $$(notdir $$(<:.o=)) > $$@ + $(Q)$$(BPFTOOL) gen subskeleton $$(<:.o=.linked3.o) name $$(notdir $$(<:.o=)) > $$(@:.skel.h=.subskel.h) $(TRUNNER_BPF_LSKELS): %.lskel.h: %.o $(BPFTOOL) | $(TRUNNER_OUTPUT) $$(call msg,GEN-SKEL,$(TRUNNER_BINARY),$$@) @@ -422,6 +429,7 @@ $(TRUNNER_BPF_SKELS_LINKED): $(TRUNNER_BPF_OBJS) $(BPFTOOL) | $(TRUNNER_OUTPUT) $(Q)diff $$(@:.skel.h=.linked2.o) $$(@:.skel.h=.linked3.o) $$(call msg,GEN-SKEL,$(TRUNNER_BINARY),$$@) $(Q)$$(BPFTOOL) gen skeleton $$(@:.skel.h=.linked3.o) name $$(notdir $$(@:.skel.h=)) > $$@ + $(Q)$$(BPFTOOL) gen subskeleton $$(@:.skel.h=.linked3.o) name $$(notdir $$(@:.skel.h=)) > $$(@:.skel.h=.subskel.h) endif # ensure we set up tests.h header generation rule just once @@ -559,6 +567,6 @@ $(OUTPUT)/bench: $(OUTPUT)/bench.o \ EXTRA_CLEAN := $(TEST_CUSTOM_PROGS) $(SCRATCH_DIR) $(HOST_SCRATCH_DIR) \ prog_tests/tests.h map_tests/tests.h verifier/tests.h \ feature bpftool \ - $(addprefix $(OUTPUT)/,*.o *.skel.h *.lskel.h no_alu32 bpf_gcc bpf_testmod.ko) + $(addprefix $(OUTPUT)/,*.o *.skel.h *.lskel.h *.subskel.h no_alu32 bpf_gcc bpf_testmod.ko) .PHONY: docs docs-clean diff --git a/tools/testing/selftests/bpf/prog_tests/subskeleton.c b/tools/testing/selftests/bpf/prog_tests/subskeleton.c new file mode 100644 index 000000000000..9c31b7004f9c --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/subskeleton.c @@ -0,0 +1,78 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) Meta Platforms, Inc. and affiliates. */ + +#include +#include "test_subskeleton.skel.h" +#include "test_subskeleton_lib.subskel.h" + +static void subskeleton_lib_setup(struct bpf_object *obj) +{ + struct test_subskeleton_lib *lib = test_subskeleton_lib__open(obj); + + if (!ASSERT_OK_PTR(lib, "open subskeleton")) + return; + + *lib->rodata.var1 = 1; + *lib->data.var2 = 2; + lib->bss.var3->var3_1 = 3; + lib->bss.var3->var3_2 = 4; + + test_subskeleton_lib__destroy(lib); +} + +static int subskeleton_lib_subresult(struct bpf_object *obj) +{ + struct test_subskeleton_lib *lib = test_subskeleton_lib__open(obj); + int result; + + if (!ASSERT_OK_PTR(lib, "open subskeleton")) + return -EINVAL; + + result = *lib->bss.libout1; + ASSERT_EQ(result, 1 + 2 + 3 + 4 + 5 + 6, "lib subresult"); + + ASSERT_OK_PTR(lib->progs.lib_perf_handler, "lib_perf_handler"); + ASSERT_STREQ(bpf_program__name(lib->progs.lib_perf_handler), + "lib_perf_handler", "program name"); + + ASSERT_OK_PTR(lib->maps.map1, "map1"); + ASSERT_STREQ(bpf_map__name(lib->maps.map1), "map1", "map name"); + + ASSERT_EQ(*lib->data.var5, 5, "__weak var5"); + ASSERT_EQ(*lib->data.var6, 6, "extern var6"); + ASSERT_TRUE(*lib->kconfig.CONFIG_BPF_SYSCALL, "CONFIG_BPF_SYSCALL"); + + test_subskeleton_lib__destroy(lib); + return result; +} + +void test_subskeleton(void) +{ + int err, result; + struct test_subskeleton *skel; + + skel = test_subskeleton__open(); + if (!ASSERT_OK_PTR(skel, "skel_open")) + return; + + skel->rodata->rovar1 = 10; + skel->rodata->var1 = 1; + subskeleton_lib_setup(skel->obj); + + err = test_subskeleton__load(skel); + if (!ASSERT_OK(err, "skel_load")) + goto cleanup; + + err = test_subskeleton__attach(skel); + if (!ASSERT_OK(err, "skel_attach")) + goto cleanup; + + /* trigger tracepoint */ + usleep(1); + + result = subskeleton_lib_subresult(skel->obj) * 10; + ASSERT_EQ(skel->bss->out1, result, "unexpected calculation"); + +cleanup: + test_subskeleton__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/test_subskeleton.c b/tools/testing/selftests/bpf/progs/test_subskeleton.c new file mode 100644 index 000000000000..006417974372 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_subskeleton.c @@ -0,0 +1,28 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) Meta Platforms, Inc. and affiliates. */ + +#include +#include +#include + +/* volatile to force a read, compiler may assume 0 otherwise */ +const volatile int rovar1; +int out1; + +/* Override weak symbol in test_subskeleton_lib */ +int var5 = 5; + +extern volatile bool CONFIG_BPF_SYSCALL __kconfig; + +extern int lib_routine(void); + +SEC("raw_tp/sys_enter") +int handler1(const void *ctx) +{ + (void) CONFIG_BPF_SYSCALL; + + out1 = lib_routine() * rovar1; + return 0; +} + +char LICENSE[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/test_subskeleton_lib.c b/tools/testing/selftests/bpf/progs/test_subskeleton_lib.c new file mode 100644 index 000000000000..ecfafe812c36 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_subskeleton_lib.c @@ -0,0 +1,61 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) Meta Platforms, Inc. and affiliates. */ + +#include +#include +#include + +/* volatile to force a read */ +const volatile int var1; +volatile int var2 = 1; +struct { + int var3_1; + __s64 var3_2; +} var3; +int libout1; + +extern volatile bool CONFIG_BPF_SYSCALL __kconfig; + +int var4[4]; + +__weak int var5 SEC(".data"); + +/* Fully contained within library extern-and-definition */ +extern int var6; + +int var7 SEC(".data.custom"); + +int (*fn_ptr)(void); + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __type(key, __u32); + __type(value, __u32); + __uint(max_entries, 16); +} map1 SEC(".maps"); + +extern struct { + __uint(type, BPF_MAP_TYPE_HASH); + __type(key, __u32); + __type(value, __u32); + __uint(max_entries, 16); +} map2 SEC(".maps"); + +int lib_routine(void) +{ + __u32 key = 1, value = 2; + + (void) CONFIG_BPF_SYSCALL; + bpf_map_update_elem(&map2, &key, &value, BPF_ANY); + + libout1 = var1 + var2 + var3.var3_1 + var3.var3_2 + var5 + var6; + return libout1; +} + +SEC("perf_event") +int lib_perf_handler(struct pt_regs *ctx) +{ + return 0; +} + +char LICENSE[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/test_subskeleton_lib2.c b/tools/testing/selftests/bpf/progs/test_subskeleton_lib2.c new file mode 100644 index 000000000000..80238486b7ce --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_subskeleton_lib2.c @@ -0,0 +1,16 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) Meta Platforms, Inc. and affiliates. */ + +#include +#include + +int var6 = 6; + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __type(key, __u32); + __type(value, __u32); + __uint(max_entries, 16); +} map2 SEC(".maps"); + +char LICENSE[] SEC("license") = "GPL";