Add test coverage for the new BPF_F_CPU and BPF_F_ALL_CPUS flags support in percpu maps. The following APIs are exercised:
* bpf_map_update_batch() * bpf_map_lookup_batch() * bpf_map_update_elem() * bpf_map__update_elem() * bpf_map_lookup_elem_flags() * bpf_map__lookup_elem()
For lru_percpu_hash map, set max_entries to 'libbpf_num_possible_cpus() + 1' and only use the first 'libbpf_num_possible_cpus()' entries. This ensures a spare entry is always available in the LRU free list, avoiding eviction.
When updating an existing key in lru_percpu_hash map:
1. l_new = prealloc_lru_pop(); /* Borrow from free list */ 2. l_old = lookup_elem_raw(); /* Found, key exists */ 3. pcpu_copy_value(); /* In-place update */ 4. bpf_lru_push_free(); /* Return l_new to free list */
Also add negative tests to verify that non-percpu array and hash maps reject the BPF_F_CPU and BPF_F_ALL_CPUS flags.
Signed-off-by: Leon Hwang leon.hwang@linux.dev --- .../selftests/bpf/prog_tests/percpu_alloc.c | 328 ++++++++++++++++++ .../selftests/bpf/progs/percpu_alloc_array.c | 32 ++ 2 files changed, 360 insertions(+)
diff --git a/tools/testing/selftests/bpf/prog_tests/percpu_alloc.c b/tools/testing/selftests/bpf/prog_tests/percpu_alloc.c index 343da65864d6..c1d0949f093f 100644 --- a/tools/testing/selftests/bpf/prog_tests/percpu_alloc.c +++ b/tools/testing/selftests/bpf/prog_tests/percpu_alloc.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 #include <test_progs.h> +#include "cgroup_helpers.h" #include "percpu_alloc_array.skel.h" #include "percpu_alloc_cgrp_local_storage.skel.h" #include "percpu_alloc_fail.skel.h" @@ -115,6 +116,321 @@ static void test_failure(void) { RUN_TESTS(percpu_alloc_fail); }
+static void test_percpu_map_op_cpu_flag(struct bpf_map *map, void *keys, size_t key_sz, u32 entries, + int nr_cpus, bool test_batch) +{ + size_t value_sz = sizeof(u32), value_sz_cpus, value_sz_total; + u32 *values = NULL, *values_percpu = NULL; + const u32 value = 0xDEADC0DE; + int i, j, cpu, map_fd, err; + u64 batch = 0, flags; + void *values_row; + u32 count, v; + LIBBPF_OPTS(bpf_map_batch_opts, batch_opts); + + value_sz_cpus = value_sz * nr_cpus; + values = calloc(entries, value_sz_cpus); + if (!ASSERT_OK_PTR(values, "calloc values")) + return; + + values_percpu = calloc(entries, roundup(value_sz, 8) * nr_cpus); + if (!ASSERT_OK_PTR(values_percpu, "calloc values_percpu")) { + free(values); + return; + } + + value_sz_total = value_sz_cpus * entries; + memset(values, 0, value_sz_total); + + map_fd = bpf_map__fd(map); + flags = BPF_F_CPU | BPF_F_ALL_CPUS; + err = bpf_map_lookup_elem_flags(map_fd, keys, values, flags); + if (!ASSERT_ERR(err, "bpf_map_lookup_elem_flags cpu|all_cpus")) + goto out; + + err = bpf_map_update_elem(map_fd, keys, values, flags); + if (!ASSERT_ERR(err, "bpf_map_update_elem cpu|all_cpus")) + goto out; + + flags = BPF_F_ALL_CPUS; + err = bpf_map_lookup_elem_flags(map_fd, keys, values, flags); + if (!ASSERT_ERR(err, "bpf_map_lookup_elem_flags all_cpus")) + goto out; + + flags = BPF_F_LOCK | BPF_F_CPU; + err = bpf_map_lookup_elem_flags(map_fd, keys, values, flags); + if (!ASSERT_ERR(err, "bpf_map_lookup_elem_flags BPF_F_LOCK")) + goto out; + + flags = BPF_F_LOCK | BPF_F_ALL_CPUS; + err = bpf_map_update_elem(map_fd, keys, values, flags); + if (!ASSERT_ERR(err, "bpf_map_update_elem BPF_F_LOCK")) + goto out; + + flags = (u64)nr_cpus << 32 | BPF_F_CPU; + err = bpf_map_update_elem(map_fd, keys, values, flags); + if (!ASSERT_EQ(err, -ERANGE, "bpf_map_update_elem -ERANGE")) + goto out; + + err = bpf_map__update_elem(map, keys, key_sz, values, value_sz, flags); + if (!ASSERT_EQ(err, -ERANGE, "bpf_map__update_elem -ERANGE")) + goto out; + + err = bpf_map_lookup_elem_flags(map_fd, keys, values, flags); + if (!ASSERT_EQ(err, -ERANGE, "bpf_map_lookup_elem_flags -ERANGE")) + goto out; + + err = bpf_map__lookup_elem(map, keys, key_sz, values, value_sz, flags); + if (!ASSERT_EQ(err, -ERANGE, "bpf_map__lookup_elem -ERANGE")) + goto out; + + for (cpu = 0; cpu < nr_cpus; cpu++) { + /* clear value on all cpus */ + values[0] = 0; + flags = BPF_F_ALL_CPUS; + for (i = 0; i < entries; i++) { + err = bpf_map__update_elem(map, keys + i * key_sz, key_sz, values, + value_sz, flags); + if (!ASSERT_OK(err, "bpf_map__update_elem all_cpus")) + goto out; + } + + /* update value on specified cpu */ + for (i = 0; i < entries; i++) { + values[0] = value; + flags = (u64)cpu << 32 | BPF_F_CPU; + err = bpf_map__update_elem(map, keys + i * key_sz, key_sz, values, + value_sz, flags); + if (!ASSERT_OK(err, "bpf_map__update_elem specified cpu")) + goto out; + + /* lookup then check value on CPUs */ + for (j = 0; j < nr_cpus; j++) { + flags = (u64)j << 32 | BPF_F_CPU; + err = bpf_map__lookup_elem(map, keys + i * key_sz, key_sz, values, + value_sz, flags); + if (!ASSERT_OK(err, "bpf_map__lookup_elem specified cpu")) + goto out; + if (!ASSERT_EQ(values[0], j != cpu ? 0 : value, + "bpf_map__lookup_elem value on specified cpu")) + goto out; + } + } + } + + if (!test_batch) + goto out; + + count = entries; + batch_opts.elem_flags = (u64)nr_cpus << 32 | BPF_F_CPU; + err = bpf_map_update_batch(map_fd, keys, values, &count, &batch_opts); + if (!ASSERT_EQ(err, -ERANGE, "bpf_map_update_batch -ERANGE")) + goto out; + + for (cpu = 0; cpu < nr_cpus; cpu++) { + memset(values, 0, value_sz_total); + + /* clear values across all CPUs */ + count = entries; + batch_opts.elem_flags = BPF_F_ALL_CPUS; + err = bpf_map_update_batch(map_fd, keys, values, &count, &batch_opts); + if (!ASSERT_OK(err, "bpf_map_update_batch all_cpus")) + goto out; + + /* update values on specified CPU */ + for (i = 0; i < entries; i++) + values[i] = value; + + count = entries; + batch_opts.elem_flags = (u64)cpu << 32 | BPF_F_CPU; + err = bpf_map_update_batch(map_fd, keys, values, &count, &batch_opts); + if (!ASSERT_OK(err, "bpf_map_update_batch specified cpu")) + goto out; + + /* lookup values on specified CPU */ + batch = 0; + count = entries; + memset(values, 0, entries * value_sz); + err = bpf_map_lookup_batch(map_fd, NULL, &batch, keys, values, &count, &batch_opts); + if (!ASSERT_TRUE(!err || err == -ENOENT, "bpf_map_lookup_batch specified cpu")) + goto out; + + for (i = 0; i < entries; i++) + if (!ASSERT_EQ(values[i], value, + "bpf_map_lookup_batch value on specified cpu")) + goto out; + + /* lookup values from all CPUs */ + batch = 0; + count = entries; + batch_opts.elem_flags = 0; + memset(values_percpu, 0, roundup(value_sz, 8) * nr_cpus * entries); + err = bpf_map_lookup_batch(map_fd, NULL, &batch, keys, values_percpu, &count, + &batch_opts); + if (!ASSERT_TRUE(!err || err == -ENOENT, "bpf_map_lookup_batch all_cpus")) + goto out; + + for (i = 0; i < entries; i++) { + values_row = (void *) values_percpu + + roundup(value_sz, 8) * i * nr_cpus; + for (j = 0; j < nr_cpus; j++) { + v = *(u32 *) (values_row + roundup(value_sz, 8) * j); + if (!ASSERT_EQ(v, j != cpu ? 0 : value, + "bpf_map_lookup_batch value all_cpus")) + goto out; + } + } + } + +out: + free(values_percpu); + free(values); +} + + +static void test_percpu_map_cpu_flag(enum bpf_map_type map_type) +{ + struct percpu_alloc_array *skel; + size_t key_sz = sizeof(int); + int *keys, nr_cpus, i, err; + struct bpf_map *map; + u32 max_entries; + + nr_cpus = libbpf_num_possible_cpus(); + if (!ASSERT_GT(nr_cpus, 0, "libbpf_num_possible_cpus")) + return; + + max_entries = nr_cpus + 1; + keys = calloc(max_entries, key_sz); + if (!ASSERT_OK_PTR(keys, "calloc keys")) + return; + + for (i = 0; i < max_entries; i++) + keys[i] = i; + + skel = percpu_alloc_array__open(); + if (!ASSERT_OK_PTR(skel, "percpu_alloc_array__open")) { + free(keys); + return; + } + + map = skel->maps.percpu; + bpf_map__set_type(map, map_type); + bpf_map__set_max_entries(map, max_entries); + + err = percpu_alloc_array__load(skel); + if (!ASSERT_OK(err, "test_percpu_alloc__load")) + goto out; + + test_percpu_map_op_cpu_flag(map, keys, key_sz, max_entries - 1, nr_cpus, true); +out: + percpu_alloc_array__destroy(skel); + free(keys); +} + +static void test_percpu_array_cpu_flag(void) +{ + test_percpu_map_cpu_flag(BPF_MAP_TYPE_PERCPU_ARRAY); +} + +static void test_percpu_hash_cpu_flag(void) +{ + test_percpu_map_cpu_flag(BPF_MAP_TYPE_PERCPU_HASH); +} + +static void test_lru_percpu_hash_cpu_flag(void) +{ + test_percpu_map_cpu_flag(BPF_MAP_TYPE_LRU_PERCPU_HASH); +} + +static void test_percpu_cgroup_storage_cpu_flag(void) +{ + struct percpu_alloc_array *skel = NULL; + struct bpf_cgroup_storage_key key; + int cgroup, prog_fd, nr_cpus, err; + struct bpf_map *map; + + nr_cpus = libbpf_num_possible_cpus(); + if (!ASSERT_GT(nr_cpus, 0, "libbpf_num_possible_cpus")) + return; + + err = setup_cgroup_environment(); + if (!ASSERT_OK(err, "setup_cgroup_environment")) + return; + + cgroup = create_and_get_cgroup("/cg_percpu"); + if (!ASSERT_GE(cgroup, 0, "create_and_get_cgroup")) { + cleanup_cgroup_environment(); + return; + } + + err = join_cgroup("/cg_percpu"); + if (!ASSERT_OK(err, "join_cgroup")) + goto out; + + skel = percpu_alloc_array__open_and_load(); + if (!ASSERT_OK_PTR(skel, "percpu_alloc_array__open_and_load")) + goto out; + + prog_fd = bpf_program__fd(skel->progs.cgroup_egress); + err = bpf_prog_attach(prog_fd, cgroup, BPF_CGROUP_INET_EGRESS, 0); + if (!ASSERT_OK(err, "bpf_prog_attach")) + goto out; + + map = skel->maps.percpu_cgroup_storage; + err = bpf_map_get_next_key(bpf_map__fd(map), NULL, &key); + if (!ASSERT_OK(err, "bpf_map_get_next_key")) + goto out; + + test_percpu_map_op_cpu_flag(map, &key, sizeof(key), 1, nr_cpus, false); +out: + bpf_prog_detach2(-1, cgroup, BPF_CGROUP_INET_EGRESS); + close(cgroup); + cleanup_cgroup_environment(); + percpu_alloc_array__destroy(skel); +} + +static void test_map_op_cpu_flag(enum bpf_map_type map_type) +{ + u32 max_entries = 1, count = max_entries; + u64 flags, batch = 0, val = 0; + int err, map_fd, key = 0; + LIBBPF_OPTS(bpf_map_batch_opts, batch_opts); + + map_fd = bpf_map_create(map_type, "test_cpu_flag", sizeof(int), sizeof(u64), max_entries, + NULL); + if (!ASSERT_GE(map_fd, 0, "bpf_map_create")) + return; + + flags = BPF_F_ALL_CPUS; + err = bpf_map_update_elem(map_fd, &key, &val, flags); + ASSERT_ERR(err, "bpf_map_update_elem all_cpus"); + + batch_opts.elem_flags = BPF_F_ALL_CPUS; + err = bpf_map_update_batch(map_fd, &key, &val, &count, &batch_opts); + ASSERT_ERR(err, "bpf_map_update_batch all_cpus"); + + flags = BPF_F_CPU; + err = bpf_map_lookup_elem_flags(map_fd, &key, &val, flags); + ASSERT_ERR(err, "bpf_map_lookup_elem_flags cpu"); + + batch_opts.elem_flags = BPF_F_CPU; + err = bpf_map_lookup_batch(map_fd, NULL, &batch, &key, &val, &count, &batch_opts); + ASSERT_ERR(err, "bpf_map_lookup_batch cpu"); + + close(map_fd); +} + +static void test_array_cpu_flag(void) +{ + test_map_op_cpu_flag(BPF_MAP_TYPE_ARRAY); +} + +static void test_hash_cpu_flag(void) +{ + test_map_op_cpu_flag(BPF_MAP_TYPE_HASH); +} + void test_percpu_alloc(void) { if (test__start_subtest("array")) @@ -125,4 +441,16 @@ void test_percpu_alloc(void) test_cgrp_local_storage(); if (test__start_subtest("failure_tests")) test_failure(); + if (test__start_subtest("cpu_flag_percpu_array")) + test_percpu_array_cpu_flag(); + if (test__start_subtest("cpu_flag_percpu_hash")) + test_percpu_hash_cpu_flag(); + if (test__start_subtest("cpu_flag_lru_percpu_hash")) + test_lru_percpu_hash_cpu_flag(); + if (test__start_subtest("cpu_flag_percpu_cgroup_storage")) + test_percpu_cgroup_storage_cpu_flag(); + if (test__start_subtest("cpu_flag_array")) + test_array_cpu_flag(); + if (test__start_subtest("cpu_flag_hash")) + test_hash_cpu_flag(); } diff --git a/tools/testing/selftests/bpf/progs/percpu_alloc_array.c b/tools/testing/selftests/bpf/progs/percpu_alloc_array.c index 37c2d2608ec0..ed6a2a93d5a5 100644 --- a/tools/testing/selftests/bpf/progs/percpu_alloc_array.c +++ b/tools/testing/selftests/bpf/progs/percpu_alloc_array.c @@ -187,4 +187,36 @@ int BPF_PROG(test_array_map_10) return 0; }
+struct { + __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY); + __uint(max_entries, 2); + __type(key, int); + __type(value, u32); +} percpu SEC(".maps"); + +SEC("?fentry/bpf_fentry_test1") +int BPF_PROG(test_percpu_array, int x) +{ + u64 value = 0xDEADC0DE; + int key = 0; + + bpf_map_update_elem(&percpu, &key, &value, BPF_ANY); + return 0; +} + +struct { + __uint(type, BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE); + __type(key, struct bpf_cgroup_storage_key); + __type(value, u32); +} percpu_cgroup_storage SEC(".maps"); + +SEC("cgroup_skb/egress") +int cgroup_egress(struct __sk_buff *skb) +{ + u32 *val = bpf_get_local_storage(&percpu_cgroup_storage, 0); + + *val = 1; + return 1; +} + char _license[] SEC("license") = "GPL";