On Thu, Feb 25, 2021 at 9:13 PM Yonghong Song <yhs@xxxxxx> wrote:
>
> 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
>
> Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
> Signed-off-by: Yonghong Song <yhs@xxxxxx>
> ---
> .../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 <test_progs.h>
> +#include <network_helpers.h>
> +#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 <bpf/bpf_helpers.h>
> +
> +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; \
> +})
Thanks for adding it!
> +
> #define ASSERT_STREQ(actual, expected, name) ({ \
> static int duration = 0; \
> const char *___act = actual; \
> --
> 2.24.1
>
