From 9de7f0fdab326a37c9f741f0f6c0f1cbc320a5ab Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Fri, 26 Feb 2021 12:49:33 -0800 Subject: [PATCH] selftests/bpf: Add hashmap test for bpf_for_each_map_elem() helper A test case is added for hashmap and percpu hashmap. The test also exercises nested bpf_for_each_map_elem() calls like bpf_prog: bpf_for_each_map_elem(func1) func1: bpf_for_each_map_elem(func2) func2: $ ./test_progs -n 45 #45/1 hash_map:OK #45 for_each:OK Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20210226204933.3885657-1-yhs@fb.com --- .../selftests/bpf/prog_tests/for_each.c | 73 ++++++++++++++ .../bpf/progs/for_each_hash_map_elem.c | 95 +++++++++++++++++++ tools/testing/selftests/bpf/test_progs.h | 11 +++ 3 files changed, 179 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/for_each.c create mode 100644 tools/testing/selftests/bpf/progs/for_each_hash_map_elem.c diff --git a/tools/testing/selftests/bpf/prog_tests/for_each.c b/tools/testing/selftests/bpf/prog_tests/for_each.c new file mode 100644 index 000000000000..aa847cd9f71f --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/for_each.c @@ -0,0 +1,73 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2021 Facebook */ +#include +#include +#include "for_each_hash_map_elem.skel.h" + +static unsigned int duration; + +static void test_hash_map(void) +{ + int i, err, hashmap_fd, max_entries, percpu_map_fd; + struct for_each_hash_map_elem *skel; + __u64 *percpu_valbuf = NULL; + __u32 key, num_cpus, retval; + __u64 val; + + skel = for_each_hash_map_elem__open_and_load(); + if (!ASSERT_OK_PTR(skel, "for_each_hash_map_elem__open_and_load")) + return; + + hashmap_fd = bpf_map__fd(skel->maps.hashmap); + max_entries = bpf_map__max_entries(skel->maps.hashmap); + for (i = 0; i < max_entries; i++) { + key = i; + val = i + 1; + err = bpf_map_update_elem(hashmap_fd, &key, &val, BPF_ANY); + if (!ASSERT_OK(err, "map_update")) + goto out; + } + + num_cpus = bpf_num_possible_cpus(); + percpu_map_fd = bpf_map__fd(skel->maps.percpu_map); + percpu_valbuf = malloc(sizeof(__u64) * num_cpus); + if (!ASSERT_OK_PTR(percpu_valbuf, "percpu_valbuf")) + goto out; + + key = 1; + for (i = 0; i < num_cpus; i++) + percpu_valbuf[i] = i + 1; + err = bpf_map_update_elem(percpu_map_fd, &key, percpu_valbuf, BPF_ANY); + if (!ASSERT_OK(err, "percpu_map_update")) + goto out; + + err = bpf_prog_test_run(bpf_program__fd(skel->progs.test_pkt_access), + 1, &pkt_v4, sizeof(pkt_v4), NULL, NULL, + &retval, &duration); + if (CHECK(err || retval, "ipv4", "err %d errno %d retval %d\n", + err, errno, retval)) + goto out; + + ASSERT_EQ(skel->bss->hashmap_output, 4, "hashmap_output"); + ASSERT_EQ(skel->bss->hashmap_elems, max_entries, "hashmap_elems"); + + key = 1; + err = bpf_map_lookup_elem(hashmap_fd, &key, &val); + ASSERT_ERR(err, "hashmap_lookup"); + + ASSERT_EQ(skel->bss->percpu_called, 1, "percpu_called"); + ASSERT_LT(skel->bss->cpu, num_cpus, "num_cpus"); + ASSERT_EQ(skel->bss->percpu_map_elems, 1, "percpu_map_elems"); + ASSERT_EQ(skel->bss->percpu_key, 1, "percpu_key"); + ASSERT_EQ(skel->bss->percpu_val, skel->bss->cpu + 1, "percpu_val"); + ASSERT_EQ(skel->bss->percpu_output, 100, "percpu_output"); +out: + free(percpu_valbuf); + for_each_hash_map_elem__destroy(skel); +} + +void test_for_each(void) +{ + if (test__start_subtest("hash_map")) + test_hash_map(); +} diff --git a/tools/testing/selftests/bpf/progs/for_each_hash_map_elem.c b/tools/testing/selftests/bpf/progs/for_each_hash_map_elem.c new file mode 100644 index 000000000000..913dd91aafff --- /dev/null +++ b/tools/testing/selftests/bpf/progs/for_each_hash_map_elem.c @@ -0,0 +1,95 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2021 Facebook */ +#include "vmlinux.h" +#include + +char _license[] SEC("license") = "GPL"; + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(max_entries, 3); + __type(key, __u32); + __type(value, __u64); +} hashmap SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_PERCPU_HASH); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, __u64); +} percpu_map SEC(".maps"); + +struct callback_ctx { + struct __sk_buff *ctx; + int input; + int output; +}; + +static __u64 +check_hash_elem(struct bpf_map *map, __u32 *key, __u64 *val, + struct callback_ctx *data) +{ + struct __sk_buff *skb = data->ctx; + __u32 k; + __u64 v; + + if (skb) { + k = *key; + v = *val; + if (skb->len == 10000 && k == 10 && v == 10) + data->output = 3; /* impossible path */ + else + data->output = 4; + } else { + data->output = data->input; + bpf_map_delete_elem(map, key); + } + + return 0; +} + +__u32 cpu = 0; +__u32 percpu_called = 0; +__u32 percpu_key = 0; +__u64 percpu_val = 0; +int percpu_output = 0; + +static __u64 +check_percpu_elem(struct bpf_map *map, __u32 *key, __u64 *val, + struct callback_ctx *unused) +{ + struct callback_ctx data; + + percpu_called++; + cpu = bpf_get_smp_processor_id(); + percpu_key = *key; + percpu_val = *val; + + data.ctx = 0; + data.input = 100; + data.output = 0; + bpf_for_each_map_elem(&hashmap, check_hash_elem, &data, 0); + percpu_output = data.output; + + return 0; +} + +int hashmap_output = 0; +int hashmap_elems = 0; +int percpu_map_elems = 0; + +SEC("classifier") +int test_pkt_access(struct __sk_buff *skb) +{ + struct callback_ctx data; + + data.ctx = skb; + data.input = 10; + data.output = 0; + hashmap_elems = bpf_for_each_map_elem(&hashmap, check_hash_elem, &data, 0); + hashmap_output = data.output; + + percpu_map_elems = bpf_for_each_map_elem(&percpu_map, check_percpu_elem, + (void *)0, 0); + return 0; +} diff --git a/tools/testing/selftests/bpf/test_progs.h b/tools/testing/selftests/bpf/test_progs.h index f7c2fd89d01a..e87c8546230e 100644 --- a/tools/testing/selftests/bpf/test_progs.h +++ b/tools/testing/selftests/bpf/test_progs.h @@ -152,6 +152,17 @@ extern int test__join_cgroup(const char *path); ___ok; \ }) +#define ASSERT_LT(actual, expected, name) ({ \ + static int duration = 0; \ + typeof(actual) ___act = (actual); \ + typeof(expected) ___exp = (expected); \ + bool ___ok = ___act < ___exp; \ + CHECK(!___ok, (name), \ + "unexpected %s: actual %lld >= expected %lld\n", \ + (name), (long long)(___act), (long long)(___exp)); \ + ___ok; \ +}) + #define ASSERT_STREQ(actual, expected, name) ({ \ static int duration = 0; \ const char *___act = actual; \ -- 2.39.5