Commit 7dd88059 authored by David Vernet's avatar David Vernet Committed by Alexei Starovoitov
Browse files

bpf/selftests: Verify struct_ops prog sleepable behavior 



In a set of prior changes, we added the ability for struct_ops programs
to be sleepable. This patch enhances the dummy_st_ops selftest suite to
validate this behavior by adding a new sleepable struct_ops entry to
dummy_st_ops.

Signed-off-by: default avatarDavid Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230125164735.785732-5-void@manifault.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 51a52a29

include/linux/bpf.h

+1 −0
Original line number Diff line number Diff line
@@ -1474,6 +1474,7 @@ struct bpf_dummy_ops { 
	int (*test_1)(struct bpf_dummy_ops_state *cb);

	int (*test_2)(struct bpf_dummy_ops_state *cb, int a1, unsigned short a2,

		      char a3, unsigned long a4);

	int (*test_sleepable)(struct bpf_dummy_ops_state *cb);

};



int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr,

net/bpf/bpf_dummy_struct_ops.c

+18 −0
Original line number Diff line number Diff line
@@ -154,6 +154,23 @@ static bool bpf_dummy_ops_is_valid_access(int off, int size, 
	return bpf_tracing_btf_ctx_access(off, size, type, prog, info);

}



static int bpf_dummy_ops_check_member(const struct btf_type *t,

				      const struct btf_member *member,

				      const struct bpf_prog *prog)

{

	u32 moff = __btf_member_bit_offset(t, member) / 8;



	switch (moff) {

	case offsetof(struct bpf_dummy_ops, test_sleepable):

		break;

	default:

		if (prog->aux->sleepable)

			return -EINVAL;

	}



	return 0;

}



static int bpf_dummy_ops_btf_struct_access(struct bpf_verifier_log *log,

					   const struct bpf_reg_state *reg,

					   int off, int size, enum bpf_access_type atype,
@@ -208,6 +225,7 @@ static void bpf_dummy_unreg(void *kdata) 
struct bpf_struct_ops bpf_bpf_dummy_ops = {

	.verifier_ops = &bpf_dummy_verifier_ops,

	.init = bpf_dummy_init,

	.check_member = bpf_dummy_ops_check_member,

	.init_member = bpf_dummy_init_member,

	.reg = bpf_dummy_reg,

	.unreg = bpf_dummy_unreg,

tools/testing/selftests/bpf/prog_tests/dummy_st_ops.c

+39 −13
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Copyright (C) 2021. Huawei Technologies Co., Ltd */

#include <test_progs.h>

#include "dummy_st_ops.skel.h"

#include "dummy_st_ops_success.skel.h"

#include "dummy_st_ops_fail.skel.h"

#include "trace_dummy_st_ops.skel.h"



/* Need to keep consistent with definition in include/linux/bpf.h */
@@ -11,17 +12,17 @@ struct bpf_dummy_ops_state { 


static void test_dummy_st_ops_attach(void)

{

	struct dummy_st_ops *skel;

	struct dummy_st_ops_success *skel;

	struct bpf_link *link;



	skel = dummy_st_ops__open_and_load();

	skel = dummy_st_ops_success__open_and_load();

	if (!ASSERT_OK_PTR(skel, "dummy_st_ops_load"))

		return;



	link = bpf_map__attach_struct_ops(skel->maps.dummy_1);

	ASSERT_EQ(libbpf_get_error(link), -EOPNOTSUPP, "dummy_st_ops_attach");



	dummy_st_ops__destroy(skel);

	dummy_st_ops_success__destroy(skel);

}



static void test_dummy_init_ret_value(void)
@@ -31,10 +32,10 @@ static void test_dummy_init_ret_value(void) 
		.ctx_in = args,

		.ctx_size_in = sizeof(args),

	);

	struct dummy_st_ops *skel;

	struct dummy_st_ops_success *skel;

	int fd, err;



	skel = dummy_st_ops__open_and_load();

	skel = dummy_st_ops_success__open_and_load();

	if (!ASSERT_OK_PTR(skel, "dummy_st_ops_load"))

		return;
@@ -43,7 +44,7 @@ static void test_dummy_init_ret_value(void) 
	ASSERT_OK(err, "test_run");

	ASSERT_EQ(attr.retval, 0xf2f3f4f5, "test_ret");



	dummy_st_ops__destroy(skel);

	dummy_st_ops_success__destroy(skel);

}



static void test_dummy_init_ptr_arg(void)
@@ -58,10 +59,10 @@ static void test_dummy_init_ptr_arg(void) 
		.ctx_size_in = sizeof(args),

	);

	struct trace_dummy_st_ops *trace_skel;

	struct dummy_st_ops *skel;

	struct dummy_st_ops_success *skel;

	int fd, err;



	skel = dummy_st_ops__open_and_load();

	skel = dummy_st_ops_success__open_and_load();

	if (!ASSERT_OK_PTR(skel, "dummy_st_ops_load"))

		return;
@@ -91,7 +92,7 @@ static void test_dummy_init_ptr_arg(void) 
	ASSERT_EQ(trace_skel->bss->val, exp_retval, "fentry_val");



done:

	dummy_st_ops__destroy(skel);

	dummy_st_ops_success__destroy(skel);

	trace_dummy_st_ops__destroy(trace_skel);

}
@@ -102,12 +103,12 @@ static void test_dummy_multiple_args(void) 
		.ctx_in = args,

		.ctx_size_in = sizeof(args),

	);

	struct dummy_st_ops *skel;

	struct dummy_st_ops_success *skel;

	int fd, err;

	size_t i;

	char name[8];



	skel = dummy_st_ops__open_and_load();

	skel = dummy_st_ops_success__open_and_load();

	if (!ASSERT_OK_PTR(skel, "dummy_st_ops_load"))

		return;
@@ -119,7 +120,28 @@ static void test_dummy_multiple_args(void) 
		ASSERT_EQ(skel->bss->test_2_args[i], args[i], name);

	}



	dummy_st_ops__destroy(skel);

	dummy_st_ops_success__destroy(skel);

}



static void test_dummy_sleepable(void)

{

	__u64 args[1] = {0};

	LIBBPF_OPTS(bpf_test_run_opts, attr,

		.ctx_in = args,

		.ctx_size_in = sizeof(args),

	);

	struct dummy_st_ops_success *skel;

	int fd, err;



	skel = dummy_st_ops_success__open_and_load();

	if (!ASSERT_OK_PTR(skel, "dummy_st_ops_load"))

		return;



	fd = bpf_program__fd(skel->progs.test_sleepable);

	err = bpf_prog_test_run_opts(fd, &attr);

	ASSERT_OK(err, "test_run");



	dummy_st_ops_success__destroy(skel);

}



void test_dummy_st_ops(void)
@@ -132,4 +154,8 @@ void test_dummy_st_ops(void) 
		test_dummy_init_ptr_arg();

	if (test__start_subtest("dummy_multiple_args"))

		test_dummy_multiple_args();

	if (test__start_subtest("dummy_sleepable"))

		test_dummy_sleepable();



	RUN_TESTS(dummy_st_ops_fail);

}

tools/testing/selftests/bpf/progs/dummy_st_ops_fail.c

0 → 100644
+27 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */



#include "vmlinux.h"

#include <bpf/bpf_helpers.h>

#include <bpf/bpf_tracing.h>



#include "bpf_misc.h"



char _license[] SEC("license") = "GPL";



SEC("struct_ops.s/test_2")

__failure __msg("attach to unsupported member test_2 of struct bpf_dummy_ops")

int BPF_PROG(test_unsupported_field_sleepable,

	     struct bpf_dummy_ops_state *state, int a1, unsigned short a2,

	     char a3, unsigned long a4)

{

	/* Tries to mark an unsleepable field in struct bpf_dummy_ops as sleepable. */

	return 0;

}



SEC(".struct_ops")

struct bpf_dummy_ops dummy_1 = {

	.test_1 = NULL,

	.test_2 = (void *)test_unsupported_field_sleepable,

	.test_sleepable = (void *)NULL,

};

tools/testing/selftests/bpf/progs/dummy_st_ops.c→tools/testing/selftests/bpf/progs/dummy_st_ops_success.c

+8 −11
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Copyright (C) 2021. Huawei Technologies Co., Ltd */

#include <linux/bpf.h>

#include "vmlinux.h"

#include <bpf/bpf_helpers.h>

#include <bpf/bpf_tracing.h>



struct bpf_dummy_ops_state {

	int val;

} __attribute__((preserve_access_index));



struct bpf_dummy_ops {

	int (*test_1)(struct bpf_dummy_ops_state *state);

	int (*test_2)(struct bpf_dummy_ops_state *state, int a1, unsigned short a2,

		      char a3, unsigned long a4);

};



char _license[] SEC("license") = "GPL";



SEC("struct_ops/test_1")
@@ -43,8 +33,15 @@ int BPF_PROG(test_2, struct bpf_dummy_ops_state *state, int a1, unsigned short a 
	return 0;

}



SEC("struct_ops.s/test_sleepable")

int BPF_PROG(test_sleepable, struct bpf_dummy_ops_state *state)

{

	return 0;

}



SEC(".struct_ops")

struct bpf_dummy_ops dummy_1 = {

	.test_1 = (void *)test_1,

	.test_2 = (void *)test_2,

	.test_sleepable = (void *)test_sleepable,

};