Commit 7b6abcfa authored by David Vernet's avatar David Vernet Committed by Alexei Starovoitov
Browse files

selftests/bpf: Add selftest suite for cpumask kfuncs 



A recent patch added a new set of kfuncs for allocating, freeing,
manipulating, and querying cpumasks. This patch adds a new 'cpumask'
selftest suite which verifies their behavior.

Signed-off-by: default avatarDavid Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230125143816.721952-5-void@manifault.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent a6541f4d

tools/testing/selftests/bpf/DENYLIST.s390x

+1 −0
Original line number Diff line number Diff line
@@ -13,6 +13,7 @@ cgroup_hierarchical_stats # JIT does not support calling kernel f 
cgrp_kfunc                               # JIT does not support calling kernel function

cgrp_local_storage                       # prog_attach unexpected error: -524                                          (trampoline)

core_read_macros                         # unknown func bpf_probe_read#4                                               (overlapping)

cpumask                                  # JIT does not support calling kernel function

d_path                                   # failed to auto-attach program 'prog_stat': -524                             (trampoline)

decap_sanity                             # JIT does not support calling kernel function                                (kfunc)

deny_namespace                           # failed to attach: ERROR: strerror_r(-524)=22                                (trampoline)

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

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+74 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

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



#include <test_progs.h>

#include "cpumask_failure.skel.h"

#include "cpumask_success.skel.h"



static const char * const cpumask_success_testcases[] = {

	"test_alloc_free_cpumask",

	"test_set_clear_cpu",

	"test_setall_clear_cpu",

	"test_first_firstzero_cpu",

	"test_test_and_set_clear",

	"test_and_or_xor",

	"test_intersects_subset",

	"test_copy_any_anyand",

	"test_insert_leave",

	"test_insert_remove_release",

	"test_insert_kptr_get_release",

};



static void verify_success(const char *prog_name)

{

	struct cpumask_success *skel;

	struct bpf_program *prog;

	struct bpf_link *link = NULL;

	pid_t child_pid;

	int status;



	skel = cpumask_success__open();

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

		return;



	skel->bss->pid = getpid();

	skel->bss->nr_cpus = libbpf_num_possible_cpus();



	cpumask_success__load(skel);

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

		goto cleanup;



	prog = bpf_object__find_program_by_name(skel->obj, prog_name);

	if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name"))

		goto cleanup;



	link = bpf_program__attach(prog);

	if (!ASSERT_OK_PTR(link, "bpf_program__attach"))

		goto cleanup;



	child_pid = fork();

	if (!ASSERT_GT(child_pid, -1, "child_pid"))

		goto cleanup;

	if (child_pid == 0)

		_exit(0);

	waitpid(child_pid, &status, 0);

	ASSERT_OK(skel->bss->err, "post_wait_err");



cleanup:

	bpf_link__destroy(link);

	cpumask_success__destroy(skel);

}



void test_cpumask(void)

{

	int i;



	for (i = 0; i < ARRAY_SIZE(cpumask_success_testcases); i++) {

		if (!test__start_subtest(cpumask_success_testcases[i]))

			continue;



		verify_success(cpumask_success_testcases[i]);

	}



	RUN_TESTS(cpumask_failure);

}

tools/testing/selftests/bpf/progs/cpumask_common.h

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+114 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

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



#ifndef _CPUMASK_COMMON_H

#define _CPUMASK_COMMON_H



#include "errno.h"

#include <stdbool.h>



int err;



struct __cpumask_map_value {

	struct bpf_cpumask __kptr_ref * cpumask;

};



struct array_map {

	__uint(type, BPF_MAP_TYPE_ARRAY);

	__type(key, int);

	__type(value, struct __cpumask_map_value);

	__uint(max_entries, 1);

} __cpumask_map SEC(".maps");



struct bpf_cpumask *bpf_cpumask_create(void) __ksym;

void bpf_cpumask_release(struct bpf_cpumask *cpumask) __ksym;

struct bpf_cpumask *bpf_cpumask_acquire(struct bpf_cpumask *cpumask) __ksym;

struct bpf_cpumask *bpf_cpumask_kptr_get(struct bpf_cpumask **cpumask) __ksym;

u32 bpf_cpumask_first(const struct cpumask *cpumask) __ksym;

u32 bpf_cpumask_first_zero(const struct cpumask *cpumask) __ksym;

void bpf_cpumask_set_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym;

void bpf_cpumask_clear_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym;

bool bpf_cpumask_test_cpu(u32 cpu, const struct cpumask *cpumask) __ksym;

bool bpf_cpumask_test_and_set_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym;

bool bpf_cpumask_test_and_clear_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym;

void bpf_cpumask_setall(struct bpf_cpumask *cpumask) __ksym;

void bpf_cpumask_clear(struct bpf_cpumask *cpumask) __ksym;

bool bpf_cpumask_and(struct bpf_cpumask *cpumask,

		     const struct cpumask *src1,

		     const struct cpumask *src2) __ksym;

void bpf_cpumask_or(struct bpf_cpumask *cpumask,

		    const struct cpumask *src1,

		    const struct cpumask *src2) __ksym;

void bpf_cpumask_xor(struct bpf_cpumask *cpumask,

		     const struct cpumask *src1,

		     const struct cpumask *src2) __ksym;

bool bpf_cpumask_equal(const struct cpumask *src1, const struct cpumask *src2) __ksym;

bool bpf_cpumask_intersects(const struct cpumask *src1, const struct cpumask *src2) __ksym;

bool bpf_cpumask_subset(const struct cpumask *src1, const struct cpumask *src2) __ksym;

bool bpf_cpumask_empty(const struct cpumask *cpumask) __ksym;

bool bpf_cpumask_full(const struct cpumask *cpumask) __ksym;

void bpf_cpumask_copy(struct bpf_cpumask *dst, const struct cpumask *src) __ksym;

u32 bpf_cpumask_any(const struct cpumask *src) __ksym;

u32 bpf_cpumask_any_and(const struct cpumask *src1, const struct cpumask *src2) __ksym;



static inline const struct cpumask *cast(struct bpf_cpumask *cpumask)

{

	return (const struct cpumask *)cpumask;

}



static inline struct bpf_cpumask *create_cpumask(void)

{

	struct bpf_cpumask *cpumask;



	cpumask = bpf_cpumask_create();

	if (!cpumask) {

		err = 1;

		return NULL;

	}



	if (!bpf_cpumask_empty(cast(cpumask))) {

		err = 2;

		bpf_cpumask_release(cpumask);

		return NULL;

	}



	return cpumask;

}



static inline struct __cpumask_map_value *cpumask_map_value_lookup(void)

{

	u32 key = 0;



	return bpf_map_lookup_elem(&__cpumask_map, &key);

}



static inline int cpumask_map_insert(struct bpf_cpumask *mask)

{

	struct __cpumask_map_value local, *v;

	long status;

	struct bpf_cpumask *old;

	u32 key = 0;



	local.cpumask = NULL;

	status = bpf_map_update_elem(&__cpumask_map, &key, &local, 0);

	if (status) {

		bpf_cpumask_release(mask);

		return status;

	}



	v = bpf_map_lookup_elem(&__cpumask_map, &key);

	if (!v) {

		bpf_cpumask_release(mask);

		return -ENOENT;

	}



	old = bpf_kptr_xchg(&v->cpumask, mask);

	if (old) {

		bpf_cpumask_release(old);

		return -EEXIST;

	}



	return 0;

}



#endif /* _CPUMASK_COMMON_H */

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

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+126 −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_tracing.h>

#include <bpf/bpf_helpers.h>

#include "bpf_misc.h"



#include "cpumask_common.h"



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



/* Prototype for all of the program trace events below:

 *

 * TRACE_EVENT(task_newtask,

 *         TP_PROTO(struct task_struct *p, u64 clone_flags)

 */



SEC("tp_btf/task_newtask")

__failure __msg("Unreleased reference")

int BPF_PROG(test_alloc_no_release, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *cpumask;



	cpumask = create_cpumask();



	/* cpumask is never released. */

	return 0;

}



SEC("tp_btf/task_newtask")

__failure __msg("NULL pointer passed to trusted arg0")

int BPF_PROG(test_alloc_double_release, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *cpumask;



	cpumask = create_cpumask();



	/* cpumask is released twice. */

	bpf_cpumask_release(cpumask);

	bpf_cpumask_release(cpumask);



	return 0;

}



SEC("tp_btf/task_newtask")

__failure __msg("bpf_cpumask_acquire args#0 expected pointer to STRUCT bpf_cpumask")

int BPF_PROG(test_acquire_wrong_cpumask, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *cpumask;



	/* Can't acquire a non-struct bpf_cpumask. */

	cpumask = bpf_cpumask_acquire((struct bpf_cpumask *)task->cpus_ptr);



	return 0;

}



SEC("tp_btf/task_newtask")

__failure __msg("bpf_cpumask_set_cpu args#1 expected pointer to STRUCT bpf_cpumask")

int BPF_PROG(test_mutate_cpumask, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *cpumask;



	/* Can't set the CPU of a non-struct bpf_cpumask. */

	bpf_cpumask_set_cpu(0, (struct bpf_cpumask *)task->cpus_ptr);



	return 0;

}



SEC("tp_btf/task_newtask")

__failure __msg("Unreleased reference")

int BPF_PROG(test_insert_remove_no_release, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *cpumask;

	struct __cpumask_map_value *v;



	cpumask = create_cpumask();

	if (!cpumask)

		return 0;



	if (cpumask_map_insert(cpumask))

		return 0;



	v = cpumask_map_value_lookup();

	if (!v)

		return 0;



	cpumask = bpf_kptr_xchg(&v->cpumask, NULL);



	/* cpumask is never released. */

	return 0;

}



SEC("tp_btf/task_newtask")

__failure __msg("Unreleased reference")

int BPF_PROG(test_kptr_get_no_release, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *cpumask;

	struct __cpumask_map_value *v;



	cpumask = create_cpumask();

	if (!cpumask)

		return 0;



	if (cpumask_map_insert(cpumask))

		return 0;



	v = cpumask_map_value_lookup();

	if (!v)

		return 0;



	cpumask = bpf_cpumask_kptr_get(&v->cpumask);



	/* cpumask is never released. */

	return 0;

}



SEC("tp_btf/task_newtask")

__failure __msg("NULL pointer passed to trusted arg0")

int BPF_PROG(test_cpumask_null, struct task_struct *task, u64 clone_flags)

{

  /* NULL passed to KF_TRUSTED_ARGS kfunc. */

	bpf_cpumask_empty(NULL);



	return 0;

}

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

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+426 −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_tracing.h>

#include <bpf/bpf_helpers.h>



#include "cpumask_common.h"



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



int pid, nr_cpus;



static bool is_test_task(void)

{

	int cur_pid = bpf_get_current_pid_tgid() >> 32;



	return pid == cur_pid;

}



static bool create_cpumask_set(struct bpf_cpumask **out1,

			       struct bpf_cpumask **out2,

			       struct bpf_cpumask **out3,

			       struct bpf_cpumask **out4)

{

	struct bpf_cpumask *mask1, *mask2, *mask3, *mask4;



	mask1 = create_cpumask();

	if (!mask1)

		return false;



	mask2 = create_cpumask();

	if (!mask2) {

		bpf_cpumask_release(mask1);

		err = 3;

		return false;

	}



	mask3 = create_cpumask();

	if (!mask3) {

		bpf_cpumask_release(mask1);

		bpf_cpumask_release(mask2);

		err = 4;

		return false;

	}



	mask4 = create_cpumask();

	if (!mask4) {

		bpf_cpumask_release(mask1);

		bpf_cpumask_release(mask2);

		bpf_cpumask_release(mask3);

		err = 5;

		return false;

	}



	*out1 = mask1;

	*out2 = mask2;

	*out3 = mask3;

	*out4 = mask4;



	return true;

}



SEC("tp_btf/task_newtask")

int BPF_PROG(test_alloc_free_cpumask, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *cpumask;



	if (!is_test_task())

		return 0;



	cpumask = create_cpumask();

	if (!cpumask)

		return 0;



	bpf_cpumask_release(cpumask);

	return 0;

}



SEC("tp_btf/task_newtask")

int BPF_PROG(test_set_clear_cpu, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *cpumask;



	if (!is_test_task())

		return 0;



	cpumask = create_cpumask();

	if (!cpumask)

		return 0;



	bpf_cpumask_set_cpu(0, cpumask);

	if (!bpf_cpumask_test_cpu(0, cast(cpumask))) {

		err = 3;

		goto release_exit;

	}



	bpf_cpumask_clear_cpu(0, cpumask);

	if (bpf_cpumask_test_cpu(0, cast(cpumask))) {

		err = 4;

		goto release_exit;

	}



release_exit:

	bpf_cpumask_release(cpumask);

	return 0;

}



SEC("tp_btf/task_newtask")

int BPF_PROG(test_setall_clear_cpu, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *cpumask;



	if (!is_test_task())

		return 0;



	cpumask = create_cpumask();

	if (!cpumask)

		return 0;



	bpf_cpumask_setall(cpumask);

	if (!bpf_cpumask_full(cast(cpumask))) {

		err = 3;

		goto release_exit;

	}



	bpf_cpumask_clear(cpumask);

	if (!bpf_cpumask_empty(cast(cpumask))) {

		err = 4;

		goto release_exit;

	}



release_exit:

	bpf_cpumask_release(cpumask);

	return 0;

}



SEC("tp_btf/task_newtask")

int BPF_PROG(test_first_firstzero_cpu, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *cpumask;



	if (!is_test_task())

		return 0;



	cpumask = create_cpumask();

	if (!cpumask)

		return 0;



	if (bpf_cpumask_first(cast(cpumask)) < nr_cpus) {

		err = 3;

		goto release_exit;

	}



	if (bpf_cpumask_first_zero(cast(cpumask)) != 0) {

		bpf_printk("first zero: %d", bpf_cpumask_first_zero(cast(cpumask)));

		err = 4;

		goto release_exit;

	}



	bpf_cpumask_set_cpu(0, cpumask);

	if (bpf_cpumask_first(cast(cpumask)) != 0) {

		err = 5;

		goto release_exit;

	}



	if (bpf_cpumask_first_zero(cast(cpumask)) != 1) {

		err = 6;

		goto release_exit;

	}



release_exit:

	bpf_cpumask_release(cpumask);

	return 0;

}



SEC("tp_btf/task_newtask")

int BPF_PROG(test_test_and_set_clear, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *cpumask;



	if (!is_test_task())

		return 0;



	cpumask = create_cpumask();

	if (!cpumask)

		return 0;



	if (bpf_cpumask_test_and_set_cpu(0, cpumask)) {

		err = 3;

		goto release_exit;

	}



	if (!bpf_cpumask_test_and_set_cpu(0, cpumask)) {

		err = 4;

		goto release_exit;

	}



	if (!bpf_cpumask_test_and_clear_cpu(0, cpumask)) {

		err = 5;

		goto release_exit;

	}



release_exit:

	bpf_cpumask_release(cpumask);

	return 0;

}



SEC("tp_btf/task_newtask")

int BPF_PROG(test_and_or_xor, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *mask1, *mask2, *dst1, *dst2;



	if (!is_test_task())

		return 0;



	if (!create_cpumask_set(&mask1, &mask2, &dst1, &dst2))

		return 0;



	bpf_cpumask_set_cpu(0, mask1);

	bpf_cpumask_set_cpu(1, mask2);



	if (bpf_cpumask_and(dst1, cast(mask1), cast(mask2))) {

		err = 6;

		goto release_exit;

	}

	if (!bpf_cpumask_empty(cast(dst1))) {

		err = 7;

		goto release_exit;

	}



	bpf_cpumask_or(dst1, cast(mask1), cast(mask2));

	if (!bpf_cpumask_test_cpu(0, cast(dst1))) {

		err = 8;

		goto release_exit;

	}

	if (!bpf_cpumask_test_cpu(1, cast(dst1))) {

		err = 9;

		goto release_exit;

	}



	bpf_cpumask_xor(dst2, cast(mask1), cast(mask2));

	if (!bpf_cpumask_equal(cast(dst1), cast(dst2))) {

		err = 10;

		goto release_exit;

	}



release_exit:

	bpf_cpumask_release(mask1);

	bpf_cpumask_release(mask2);

	bpf_cpumask_release(dst1);

	bpf_cpumask_release(dst2);

	return 0;

}



SEC("tp_btf/task_newtask")

int BPF_PROG(test_intersects_subset, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *mask1, *mask2, *dst1, *dst2;



	if (!is_test_task())

		return 0;



	if (!create_cpumask_set(&mask1, &mask2, &dst1, &dst2))

		return 0;



	bpf_cpumask_set_cpu(0, mask1);

	bpf_cpumask_set_cpu(1, mask2);

	if (bpf_cpumask_intersects(cast(mask1), cast(mask2))) {

		err = 6;

		goto release_exit;

	}



	bpf_cpumask_or(dst1, cast(mask1), cast(mask2));

	if (!bpf_cpumask_subset(cast(mask1), cast(dst1))) {

		err = 7;

		goto release_exit;

	}



	if (!bpf_cpumask_subset(cast(mask2), cast(dst1))) {

		err = 8;

		goto release_exit;

	}



	if (bpf_cpumask_subset(cast(dst1), cast(mask1))) {

		err = 9;

		goto release_exit;

	}



release_exit:

	bpf_cpumask_release(mask1);

	bpf_cpumask_release(mask2);

	bpf_cpumask_release(dst1);

	bpf_cpumask_release(dst2);

	return 0;

}



SEC("tp_btf/task_newtask")

int BPF_PROG(test_copy_any_anyand, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *mask1, *mask2, *dst1, *dst2;

	u32 cpu;



	if (!is_test_task())

		return 0;



	if (!create_cpumask_set(&mask1, &mask2, &dst1, &dst2))

		return 0;



	bpf_cpumask_set_cpu(0, mask1);

	bpf_cpumask_set_cpu(1, mask2);

	bpf_cpumask_or(dst1, cast(mask1), cast(mask2));



	cpu = bpf_cpumask_any(cast(mask1));

	if (cpu != 0) {

		err = 6;

		goto release_exit;

	}



	cpu = bpf_cpumask_any(cast(dst2));

	if (cpu < nr_cpus) {

		err = 7;

		goto release_exit;

	}



	bpf_cpumask_copy(dst2, cast(dst1));

	if (!bpf_cpumask_equal(cast(dst1), cast(dst2))) {

		err = 8;

		goto release_exit;

	}



	cpu = bpf_cpumask_any(cast(dst2));

	if (cpu > 1) {

		err = 9;

		goto release_exit;

	}



	cpu = bpf_cpumask_any_and(cast(mask1), cast(mask2));

	if (cpu < nr_cpus) {

		err = 10;

		goto release_exit;

	}



release_exit:

	bpf_cpumask_release(mask1);

	bpf_cpumask_release(mask2);

	bpf_cpumask_release(dst1);

	bpf_cpumask_release(dst2);

	return 0;

}



SEC("tp_btf/task_newtask")

int BPF_PROG(test_insert_leave, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *cpumask;

	struct __cpumask_map_value *v;



	cpumask = create_cpumask();

	if (!cpumask)

		return 0;



	if (cpumask_map_insert(cpumask))

		err = 3;



	return 0;

}



SEC("tp_btf/task_newtask")

int BPF_PROG(test_insert_remove_release, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *cpumask;

	struct __cpumask_map_value *v;



	cpumask = create_cpumask();

	if (!cpumask)

		return 0;



	if (cpumask_map_insert(cpumask)) {

		err = 3;

		return 0;

	}



	v = cpumask_map_value_lookup();

	if (!v) {

		err = 4;

		return 0;

	}



	cpumask = bpf_kptr_xchg(&v->cpumask, NULL);

	if (cpumask)

		bpf_cpumask_release(cpumask);

	else

		err = 5;



	return 0;

}



SEC("tp_btf/task_newtask")

int BPF_PROG(test_insert_kptr_get_release, struct task_struct *task, u64 clone_flags)

{

	struct bpf_cpumask *cpumask;

	struct __cpumask_map_value *v;



	cpumask = create_cpumask();

	if (!cpumask)

		return 0;



	if (cpumask_map_insert(cpumask)) {

		err = 3;

		return 0;

	}



	v = cpumask_map_value_lookup();

	if (!v) {

		err = 4;

		return 0;

	}



	cpumask = bpf_cpumask_kptr_get(&v->cpumask);

	if (cpumask)

		bpf_cpumask_release(cpumask);

	else

		err = 5;



	return 0;

}