Extend the existing bpf_map_lookup_and_delete_elem() functionality to hashtab maps, in addition to stacks and queues. Add bpf_map_lookup_and_delete_elem_flags() libbpf API in order to use the BPF_F_LOCK flag. Create a new hashtab bpf_map_ops function that does lookup and deletion of the element under the same bucket lock and add the created map_ops to bpf.h. Add the appropriate test cases to 'maps' and 'lru_map' selftests accompanied with new test_progs. Cc: Juraj Vijtiuk <juraj.vijtiuk@xxxxxxxxxx> Cc: Luka Oreskovic <luka.oreskovic@xxxxxxxxxx> Cc: Luka Perkov <luka.perkov@xxxxxxxxxx> Signed-off-by: Denis Salopek <denis.salopek@xxxxxxxxxx> --- v2: Add functionality for LRU/per-CPU, add test_progs tests. v3: Add bpf_map_lookup_and_delete_elem_flags() and enable BPF_F_LOCK flag, change CHECKs to ASSERT_OKs, initialize variables to 0. --- include/linux/bpf.h | 2 + kernel/bpf/hashtab.c | 97 ++++++ kernel/bpf/syscall.c | 24 +- tools/lib/bpf/bpf.c | 13 + tools/lib/bpf/bpf.h | 2 + tools/lib/bpf/libbpf.map | 1 + .../bpf/prog_tests/lookup_and_delete.c | 279 ++++++++++++++++++ .../bpf/progs/test_lookup_and_delete.c | 26 ++ tools/testing/selftests/bpf/test_lru_map.c | 8 + tools/testing/selftests/bpf/test_maps.c | 19 +- 10 files changed, 468 insertions(+), 3 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/lookup_and_delete.c create mode 100644 tools/testing/selftests/bpf/progs/test_lookup_and_delete.c diff --git a/include/linux/bpf.h b/include/linux/bpf.h index a25730eaa148..9e07fc7312c0 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -67,6 +67,8 @@ struct bpf_map_ops { void *(*map_lookup_elem_sys_only)(struct bpf_map *map, void *key); int (*map_lookup_batch)(struct bpf_map *map, const union bpf_attr *attr, union bpf_attr __user *uattr); + int (*map_lookup_and_delete_elem)(struct bpf_map *map, void *key, + void *value, u64 flags); int (*map_lookup_and_delete_batch)(struct bpf_map *map, const union bpf_attr *attr, union bpf_attr __user *uattr); diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index 330d721dd2af..e5c754878cfd 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -1401,6 +1401,99 @@ static void htab_map_seq_show_elem(struct bpf_map *map, void *key, rcu_read_unlock(); } +static int __htab_map_lookup_and_delete_elem(struct bpf_map *map, void *key, + void *value, bool is_lru_map, + bool is_percpu, u64 flags) +{ + struct bpf_htab *htab = container_of(map, struct bpf_htab, map); + u32 hash, key_size, value_size; + struct hlist_nulls_head *head; + int cpu, off = 0, ret; + struct htab_elem *l; + unsigned long bflags; + void __percpu *pptr; + struct bucket *b; + + if ((flags & ~BPF_F_LOCK) || + ((flags & BPF_F_LOCK) && !map_value_has_spin_lock(map))) + return -EINVAL; + + key_size = map->key_size; + value_size = round_up(map->value_size, 8); + + hash = htab_map_hash(key, key_size, htab->hashrnd); + b = __select_bucket(htab, hash); + head = &b->head; + + ret = htab_lock_bucket(htab, b, hash, &bflags); + if (ret) + return ret; + + l = lookup_elem_raw(head, hash, key, key_size); + if (l) { + if (is_percpu) { + pptr = htab_elem_get_ptr(l, key_size); + for_each_possible_cpu(cpu) { + bpf_long_memcpy(value + off, + per_cpu_ptr(pptr, cpu), + value_size); + off += value_size; + } + } else { + if (flags & BPF_F_LOCK) + copy_map_value_locked(map, value, l->key + + round_up(key_size, 8), + true); + else + copy_map_value(map, value, l->key + + round_up(key_size, 8)); + check_and_init_map_lock(map, value); + } + + hlist_nulls_del_rcu(&l->hash_node); + if (!is_lru_map) + free_htab_elem(htab, l); + } else + ret = -ENOENT; + + htab_unlock_bucket(htab, b, hash, bflags); + + if (is_lru_map && l) + bpf_lru_push_free(&htab->lru, &l->lru_node); + + return ret; +} + +static int htab_map_lookup_and_delete_elem(struct bpf_map *map, void *key, + void *value, u64 flags) +{ + return __htab_map_lookup_and_delete_elem(map, key, value, false, false, + flags); +} + +static int htab_percpu_map_lookup_and_delete_elem(struct bpf_map *map, + void *key, void *value, + u64 flags) +{ + return __htab_map_lookup_and_delete_elem(map, key, value, false, true, + flags); +} + +static int htab_lru_map_lookup_and_delete_elem(struct bpf_map *map, void *key, + void *value, u64 flags) +{ + return __htab_map_lookup_and_delete_elem(map, key, value, true, false, + flags); +} + +static int htab_lru_percpu_map_lookup_and_delete_elem(struct bpf_map *map, + void *key, void *value, + u64 flags) +{ + return __htab_map_lookup_and_delete_elem(map, key, value, true, true, + flags); +} + static int __htab_map_lookup_and_delete_batch(struct bpf_map *map, const union bpf_attr *attr, @@ -1934,6 +2027,7 @@ const struct bpf_map_ops htab_map_ops = { .map_free = htab_map_free, .map_get_next_key = htab_map_get_next_key, .map_lookup_elem = htab_map_lookup_elem, + .map_lookup_and_delete_elem = htab_map_lookup_and_delete_elem, .map_update_elem = htab_map_update_elem, .map_delete_elem = htab_map_delete_elem, .map_gen_lookup = htab_map_gen_lookup, @@ -1954,6 +2048,7 @@ const struct bpf_map_ops htab_lru_map_ops = { .map_free = htab_map_free, .map_get_next_key = htab_map_get_next_key, .map_lookup_elem = htab_lru_map_lookup_elem, + .map_lookup_and_delete_elem = htab_lru_map_lookup_and_delete_elem, .map_lookup_elem_sys_only = htab_lru_map_lookup_elem_sys, .map_update_elem = htab_lru_map_update_elem, .map_delete_elem = htab_lru_map_delete_elem, @@ -2077,6 +2172,7 @@ const struct bpf_map_ops htab_percpu_map_ops = { .map_free = htab_map_free, .map_get_next_key = htab_map_get_next_key, .map_lookup_elem = htab_percpu_map_lookup_elem, + .map_lookup_and_delete_elem = htab_percpu_map_lookup_and_delete_elem, .map_update_elem = htab_percpu_map_update_elem, .map_delete_elem = htab_map_delete_elem, .map_seq_show_elem = htab_percpu_map_seq_show_elem, @@ -2096,6 +2192,7 @@ const struct bpf_map_ops htab_lru_percpu_map_ops = { .map_free = htab_map_free, .map_get_next_key = htab_map_get_next_key, .map_lookup_elem = htab_lru_percpu_map_lookup_elem, + .map_lookup_and_delete_elem = htab_lru_percpu_map_lookup_and_delete_elem, .map_update_elem = htab_lru_percpu_map_update_elem, .map_delete_elem = htab_lru_map_delete_elem, .map_seq_show_elem = htab_percpu_map_seq_show_elem, diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index c859bc46d06c..36f65b589b82 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1463,7 +1463,7 @@ int generic_map_lookup_batch(struct bpf_map *map, return err; } -#define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD value +#define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags static int map_lookup_and_delete_elem(union bpf_attr *attr) { @@ -1479,6 +1479,9 @@ static int map_lookup_and_delete_elem(union bpf_attr *attr) if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM)) return -EINVAL; + if (attr->flags & ~BPF_F_LOCK) + return -EINVAL; + f = fdget(ufd); map = __bpf_map_get(f); if (IS_ERR(map)) @@ -1489,13 +1492,19 @@ static int map_lookup_and_delete_elem(union bpf_attr *attr) goto err_put; } + if ((attr->flags & BPF_F_LOCK) && + !map_value_has_spin_lock(map)) { + err = -EINVAL; + goto err_put; + } + key = __bpf_copy_key(ukey, map->key_size); if (IS_ERR(key)) { err = PTR_ERR(key); goto err_put; } - value_size = map->value_size; + value_size = bpf_map_value_size(map); err = -ENOMEM; value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); @@ -1505,6 +1514,17 @@ static int map_lookup_and_delete_elem(union bpf_attr *attr) if (map->map_type == BPF_MAP_TYPE_QUEUE || map->map_type == BPF_MAP_TYPE_STACK) { err = map->ops->map_pop_elem(map, value); + } else if (map->map_type == BPF_MAP_TYPE_HASH || + map->map_type == BPF_MAP_TYPE_PERCPU_HASH || + map->map_type == BPF_MAP_TYPE_LRU_HASH || + map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { + if (!bpf_map_is_dev_bound(map)) { + bpf_disable_instrumentation(); + rcu_read_lock(); + err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags); + rcu_read_unlock(); + bpf_enable_instrumentation(); + } } else { err = -ENOTSUPP; } diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index bba48ff4c5c0..b7c2cc12034c 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -458,6 +458,19 @@ int bpf_map_lookup_and_delete_elem(int fd, const void *key, void *value) return sys_bpf(BPF_MAP_LOOKUP_AND_DELETE_ELEM, &attr, sizeof(attr)); } +int bpf_map_lookup_and_delete_elem_flags(int fd, const void *key, void *value, __u64 flags) +{ + union bpf_attr attr; + + memset(&attr, 0, sizeof(attr)); + attr.map_fd = fd; + attr.key = ptr_to_u64(key); + attr.value = ptr_to_u64(value); + attr.flags = flags; + + return sys_bpf(BPF_MAP_LOOKUP_AND_DELETE_ELEM, &attr, sizeof(attr)); +} + int bpf_map_delete_elem(int fd, const void *key) { union bpf_attr attr; diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h index 875dde20d56e..4f758f8f50cd 100644 --- a/tools/lib/bpf/bpf.h +++ b/tools/lib/bpf/bpf.h @@ -124,6 +124,8 @@ LIBBPF_API int bpf_map_lookup_elem_flags(int fd, const void *key, void *value, __u64 flags); LIBBPF_API int bpf_map_lookup_and_delete_elem(int fd, const void *key, void *value); +LIBBPF_API int bpf_map_lookup_and_delete_elem_flags(int fd, const void *key, + void *value, __u64 flags); LIBBPF_API int bpf_map_delete_elem(int fd, const void *key); LIBBPF_API int bpf_map_get_next_key(int fd, const void *key, void *next_key); LIBBPF_API int bpf_map_freeze(int fd); diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index ec898f464ab9..f4d3cbd8193b 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -132,6 +132,7 @@ LIBBPF_0.0.2 { bpf_probe_prog_type; bpf_map__resize; bpf_map_lookup_elem_flags; + bpf_map_lookup_and_delete_elem_flags; bpf_object__btf; bpf_object__find_map_fd_by_name; bpf_get_link_xdp_id; diff --git a/tools/testing/selftests/bpf/prog_tests/lookup_and_delete.c b/tools/testing/selftests/bpf/prog_tests/lookup_and_delete.c new file mode 100644 index 000000000000..8ace0e4a2349 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/lookup_and_delete.c @@ -0,0 +1,279 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include <test_progs.h> +#include "test_lookup_and_delete.skel.h" + +#define START_VALUE 1234 +#define NEW_VALUE 4321 +#define MAX_ENTRIES 2 + +static int duration; +static int nr_cpus; + +static int fill_values(int map_fd) +{ + __u64 key, value = START_VALUE; + int err; + + for (key = 1; key < MAX_ENTRIES + 1; key++) { + err = bpf_map_update_elem(map_fd, &key, &value, BPF_NOEXIST); + if (!ASSERT_OK(err, "bpf_map_update_elem")) + return -1; + } + + return 0; +} + +static int fill_values_percpu(int map_fd) +{ + BPF_DECLARE_PERCPU(__u64, value); + int i, err; + u64 key; + + for (i = 0; i < nr_cpus; i++) + bpf_percpu(value, i) = START_VALUE; + + for (key = 1; key < MAX_ENTRIES + 1; key++) { + err = bpf_map_update_elem(map_fd, &key, value, BPF_NOEXIST); + if (!ASSERT_OK(err, "bpf_map_update_elem")) + return -1; + } + + return 0; +} + +static struct test_lookup_and_delete *setup_prog(enum bpf_map_type map_type, + int *map_fd) +{ + struct test_lookup_and_delete *skel; + int err; + + skel = test_lookup_and_delete__open(); + if (!ASSERT_OK(!skel, "test_lookup_and_delete__open")) + return NULL; + + err = bpf_map__set_type(skel->maps.hash_map, map_type); + if (!ASSERT_OK(err, "bpf_map__set_type")) + goto error; + + err = test_lookup_and_delete__load(skel); + if (!ASSERT_OK(err, "test_lookup_and_delete__load")) + goto error; + + *map_fd = bpf_map__fd(skel->maps.hash_map); + if (CHECK(*map_fd < 0, "bpf_map__fd", "failed\n")) + goto error; + + return skel; + +error: + test_lookup_and_delete__destroy(skel); + return NULL; +} + +/* Triggers BPF program that updates map with given key and value */ +static int trigger_tp(struct test_lookup_and_delete *skel, __u64 key, + __u64 value) +{ + int err; + + skel->bss->set_pid = getpid(); + skel->bss->set_key = key; + skel->bss->set_value = value; + + err = test_lookup_and_delete__attach(skel); + if (!ASSERT_OK(err, "test_lookup_and_delete__attach")) + return -1; + + syscall(__NR_getpgid); + + test_lookup_and_delete__detach(skel); + + return 0; +} + +static void test_lookup_and_delete_hash(void) +{ + struct test_lookup_and_delete *skel; + __u64 key, value; + int map_fd, err; + + /* Setup program and fill the map. */ + skel = setup_prog(BPF_MAP_TYPE_HASH, &map_fd); + if (!ASSERT_OK_PTR(skel, "setup_prog")) + return; + + err = fill_values(map_fd); + if (!ASSERT_OK(err, "fill_values")) + goto cleanup; + + /* Lookup and delete element. */ + key = 1; + err = bpf_map_lookup_and_delete_elem(map_fd, &key, &value); + if (!ASSERT_OK(err, "bpf_map_lookup_and_delete_elem")) + goto cleanup; + + /* Fetched value should match the initially set value. */ + if (CHECK(value != START_VALUE, "bpf_map_lookup_and_delete_elem", + "unexpected value=%lld\n", value)) + goto cleanup; + + /* Check that the entry is non existent. */ + err = bpf_map_lookup_elem(map_fd, &key, &value); + if (!ASSERT_OK(!err, "bpf_map_lookup_elem")) + goto cleanup; + +cleanup: + test_lookup_and_delete__destroy(skel); +} + +static void test_lookup_and_delete_percpu_hash(void) +{ + struct test_lookup_and_delete *skel; + BPF_DECLARE_PERCPU(__u64, value); + int map_fd, err, i; + __u64 key, val; + + /* Setup program and fill the map. */ + skel = setup_prog(BPF_MAP_TYPE_PERCPU_HASH, &map_fd); + if (!ASSERT_OK_PTR(skel, "setup_prog")) + return; + + err = fill_values_percpu(map_fd); + if (!ASSERT_OK(err, "fill_values_percpu")) + goto cleanup; + + /* Lookup and delete element. */ + key = 1; + err = bpf_map_lookup_and_delete_elem(map_fd, &key, value); + if (!ASSERT_OK(err, "bpf_map_lookup_and_delete_elem")) + goto cleanup; + + for (i = 0; i < nr_cpus; i++) { + if (bpf_percpu(value, i)) + val = bpf_percpu(value, i); + } + + /* Fetched value should match the initially set value. */ + if (CHECK(val != START_VALUE, "bpf_map_lookup_and_delete_elem", + "unexpected value=%lld\n", val)) + goto cleanup; + + /* Check that the entry is non existent. */ + err = bpf_map_lookup_elem(map_fd, &key, value); + if (!ASSERT_OK(!err, "bpf_map_lookup_elem")) + goto cleanup; + +cleanup: + test_lookup_and_delete__destroy(skel); +} + +static void test_lookup_and_delete_lru_hash(void) +{ + struct test_lookup_and_delete *skel; + __u64 key, value; + int map_fd, err; + + /* Setup program and fill the LRU map. */ + skel = setup_prog(BPF_MAP_TYPE_LRU_HASH, &map_fd); + if (!ASSERT_OK_PTR(skel, "setup_prog")) + return; + + err = fill_values(map_fd); + if (!ASSERT_OK(err, "fill_values")) + goto cleanup; + + /* Insert new element at key=3, should reuse LRU element. */ + key = 3; + err = trigger_tp(skel, key, NEW_VALUE); + if (!ASSERT_OK(err, "trigger_tp")) + goto cleanup; + + /* Lookup and delete element 3. */ + err = bpf_map_lookup_and_delete_elem(map_fd, &key, &value); + if (!ASSERT_OK(err, "bpf_map_lookup_and_delete_elem")) + goto cleanup; + + /* Value should match the new value. */ + if (CHECK(value != NEW_VALUE, "bpf_map_lookup_and_delete_elem", + "unexpected value=%lld\n", value)) + goto cleanup; + + /* Check that entries 3 and 1 are non existent. */ + err = bpf_map_lookup_elem(map_fd, &key, &value); + if (!ASSERT_OK(!err, "bpf_map_lookup_elem")) + goto cleanup; + + key = 1; + err = bpf_map_lookup_elem(map_fd, &key, &value); + if (!ASSERT_OK(!err, "bpf_map_lookup_elem")) + goto cleanup; + +cleanup: + test_lookup_and_delete__destroy(skel); +} + +static void test_lookup_and_delete_lru_percpu_hash(void) +{ + struct test_lookup_and_delete *skel; + BPF_DECLARE_PERCPU(__u64, value); + int map_fd, err, i; + __u64 key, val; + + /* Setup program and fill the LRU map. */ + skel = setup_prog(BPF_MAP_TYPE_LRU_PERCPU_HASH, &map_fd); + if (!ASSERT_OK_PTR(skel, "setup_prog")) + return; + + err = fill_values_percpu(map_fd); + if (!ASSERT_OK(err, "fill_values_percpu")) + goto cleanup; + + /* Insert new element at key=3, should reuse LRU element. */ + key = 3; + err = trigger_tp(skel, key, NEW_VALUE); + if (!ASSERT_OK(err, "trigger_tp")) + goto cleanup; + + /* Lookup and delete element 3. */ + err = bpf_map_lookup_and_delete_elem(map_fd, &key, &value); + if (!ASSERT_OK(err, "bpf_map_lookup_and_delete_elem")) + goto cleanup; + + for (i = 0; i < nr_cpus; i++) { + if (bpf_percpu(value, i)) + val = bpf_percpu(value, i); + } + + /* Value should match the new value. */ + if (CHECK(val != NEW_VALUE, "bpf_map_lookup_and_delete_elem", + "unexpected value=%lld\n", val)) + goto cleanup; + + /* Check that entries 3 and 1 are non existent. */ + err = bpf_map_lookup_elem(map_fd, &key, &value); + if (!ASSERT_OK(!err, "bpf_map_lookup_elem")) + goto cleanup; + + key = 1; + err = bpf_map_lookup_elem(map_fd, &key, &value); + if (!ASSERT_OK(!err, "bpf_map_lookup_elem")) + goto cleanup; + +cleanup: + test_lookup_and_delete__destroy(skel); +} + +void test_lookup_and_delete(void) +{ + nr_cpus = bpf_num_possible_cpus(); + + if (test__start_subtest("lookup_and_delete")) + test_lookup_and_delete_hash(); + if (test__start_subtest("lookup_and_delete_percpu")) + test_lookup_and_delete_percpu_hash(); + if (test__start_subtest("lookup_and_delete_lru")) + test_lookup_and_delete_lru_hash(); + if (test__start_subtest("lookup_and_delete_lru_percpu")) + test_lookup_and_delete_lru_percpu_hash(); +} diff --git a/tools/testing/selftests/bpf/progs/test_lookup_and_delete.c b/tools/testing/selftests/bpf/progs/test_lookup_and_delete.c new file mode 100644 index 000000000000..3a193f42c7e7 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_lookup_and_delete.c @@ -0,0 +1,26 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> + +__u32 set_pid = 0; +__u64 set_key = 0; +__u64 set_value = 0; + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(max_entries, 2); + __type(key, __u64); + __type(value, __u64); +} hash_map SEC(".maps"); + +SEC("tp/syscalls/sys_enter_getpgid") +int bpf_lookup_and_delete_test(const void *ctx) +{ + if (set_pid == bpf_get_current_pid_tgid() >> 32) + bpf_map_update_elem(&hash_map, &set_key, &set_value, BPF_NOEXIST); + + return 0; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/test_lru_map.c b/tools/testing/selftests/bpf/test_lru_map.c index 6a5349f9eb14..f33fb6de76bc 100644 --- a/tools/testing/selftests/bpf/test_lru_map.c +++ b/tools/testing/selftests/bpf/test_lru_map.c @@ -231,6 +231,14 @@ static void test_lru_sanity0(int map_type, int map_flags) assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 && errno == ENOENT); + /* lookup elem key=3 and delete it, than check it doesn't exist */ + key = 1; + assert(!bpf_map_lookup_and_delete_elem(lru_map_fd, &key, &value)); + assert(value[0] == 1234); + + /* remove the same element from the expected map */ + assert(!bpf_map_delete_elem(expected_map_fd, &key)); + assert(map_equal(lru_map_fd, expected_map_fd)); close(expected_map_fd); diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c index 51adc42b2b40..dbd5f95e8bde 100644 --- a/tools/testing/selftests/bpf/test_maps.c +++ b/tools/testing/selftests/bpf/test_maps.c @@ -65,6 +65,13 @@ static void test_hashmap(unsigned int task, void *data) assert(bpf_map_lookup_elem(fd, &key, &value) == 0 && value == 1234); key = 2; + value = 1234; + /* Insert key=2 element. */ + assert(bpf_map_update_elem(fd, &key, &value, BPF_ANY) == 0); + + /* Check that key=2 matches the value and delete it */ + assert(bpf_map_lookup_and_delete_elem(fd, &key, &value) == 0 && value == 1234); + /* Check that key=2 is not found. */ assert(bpf_map_lookup_elem(fd, &key, &value) == -1 && errno == ENOENT); @@ -164,8 +171,18 @@ static void test_hashmap_percpu(unsigned int task, void *data) key = 1; /* Insert key=1 element. */ - assert(!(expected_key_mask & key)); assert(bpf_map_update_elem(fd, &key, value, BPF_ANY) == 0); + + /* Lookup and delete elem key=1 and check value. */ + assert(bpf_map_lookup_and_delete_elem(fd, &key, value) == 0 && + bpf_percpu(value, 0) == 100); + + for (i = 0; i < nr_cpus; i++) + bpf_percpu(value, i) = i + 100; + + /* Insert key=1 element which should not exist. */ + assert(!(expected_key_mask & key)); + assert(bpf_map_update_elem(fd, &key, value, BPF_NOEXIST) == 0); expected_key_mask |= key; /* BPF_NOEXIST means add new element if it doesn't exist. */ -- 2.26.2