Commit 5ff54ded authored by Feng Zhou's avatar Feng Zhou Committed by Alexei Starovoitov
Browse files

selftests/bpf: Add test to access integer type of variable array 



Add prog test for accessing integer type of variable array in tracing
program.
In addition, hook load_balance function to access sd->span[0], only
to confirm whether the load is successful. Because there is no direct
way to trigger load_balance call.

Co-developed-by: default avatarChengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: default avatarChengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: default avatarFeng Zhou <zhoufeng.zf@bytedance.com>
Link: https://lore.kernel.org/r/20230420032735.27760-3-zhoufeng.zf@bytedance.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 2569c7b8

tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c

+20 −0
Original line number Diff line number Diff line
@@ -28,6 +28,11 @@ struct bpf_testmod_struct_arg_2 { 
	long b;

};



struct bpf_testmod_struct_arg_3 {

	int a;

	int b[];

};



__diag_push();

__diag_ignore_all("-Wmissing-prototypes",

		  "Global functions as their definitions will be in bpf_testmod.ko BTF");
@@ -63,6 +68,12 @@ bpf_testmod_test_struct_arg_5(void) { 
	return bpf_testmod_test_struct_arg_result;

}



noinline int

bpf_testmod_test_struct_arg_6(struct bpf_testmod_struct_arg_3 *a) {

	bpf_testmod_test_struct_arg_result = a->b[0];

	return bpf_testmod_test_struct_arg_result;

}



__bpf_kfunc void

bpf_testmod_test_mod_kfunc(int i)

{
@@ -195,6 +206,7 @@ bpf_testmod_test_read(struct file *file, struct kobject *kobj, 
	};

	struct bpf_testmod_struct_arg_1 struct_arg1 = {10};

	struct bpf_testmod_struct_arg_2 struct_arg2 = {2, 3};

	struct bpf_testmod_struct_arg_3 *struct_arg3;

	int i = 1;



	while (bpf_testmod_return_ptr(i))
@@ -206,6 +218,14 @@ bpf_testmod_test_read(struct file *file, struct kobject *kobj, 
	(void)bpf_testmod_test_struct_arg_4(struct_arg1, 1, 2, 3, struct_arg2);

	(void)bpf_testmod_test_struct_arg_5();



	struct_arg3 = kmalloc((sizeof(struct bpf_testmod_struct_arg_3) +

				sizeof(int)), GFP_KERNEL);

	if (struct_arg3 != NULL) {

		struct_arg3->b[0] = 1;

		(void)bpf_testmod_test_struct_arg_6(struct_arg3);

		kfree(struct_arg3);

	}



	/* This is always true. Use the check to make sure the compiler

	 * doesn't remove bpf_testmod_loop_test.

	 */

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

0 → 100644
+16 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Copyright (c) 2022 Bytedance */



#include <test_progs.h>

#include "test_access_variable_array.skel.h"



void test_access_variable_array(void)

{

	struct test_access_variable_array *skel;



	skel = test_access_variable_array__open_and_load();

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

		return;



	test_access_variable_array__destroy(skel);

}

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

+2 −0
Original line number Diff line number Diff line
@@ -53,6 +53,8 @@ static void test_fentry(void) 


	ASSERT_EQ(skel->bss->t5_ret, 1, "t5 ret");



	ASSERT_EQ(skel->bss->t6, 1, "t6 ret");



	tracing_struct__detach(skel);

destroy_skel:

	tracing_struct__destroy(skel);

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

0 → 100644
+19 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Copyright (c) 2023 Bytedance */



#include "vmlinux.h"

#include <bpf/bpf_helpers.h>

#include <bpf/bpf_tracing.h>



unsigned long span = 0;



SEC("fentry/load_balance")

int BPF_PROG(fentry_fentry, int this_cpu, struct rq *this_rq,

		struct sched_domain *sd)

{

	span = sd->span[0];



	return 0;

}



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

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

+13 −0
Original line number Diff line number Diff line
@@ -13,12 +13,18 @@ struct bpf_testmod_struct_arg_2 { 
	long b;

};



struct bpf_testmod_struct_arg_3 {

	int a;

	int b[];

};



long t1_a_a, t1_a_b, t1_b, t1_c, t1_ret, t1_nregs;

__u64 t1_reg0, t1_reg1, t1_reg2, t1_reg3;

long t2_a, t2_b_a, t2_b_b, t2_c, t2_ret;

long t3_a, t3_b, t3_c_a, t3_c_b, t3_ret;

long t4_a_a, t4_b, t4_c, t4_d, t4_e_a, t4_e_b, t4_ret;

long t5_ret;

int t6;



SEC("fentry/bpf_testmod_test_struct_arg_1")

int BPF_PROG2(test_struct_arg_1, struct bpf_testmod_struct_arg_2, a, int, b, int, c)
@@ -117,4 +123,11 @@ int BPF_PROG2(test_struct_arg_10, int, ret) 
	return 0;

}



SEC("fentry/bpf_testmod_test_struct_arg_6")

int BPF_PROG2(test_struct_arg_11, struct bpf_testmod_struct_arg_3 *, a)

{

	t6 = a->b[0];

	return 0;

}



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