diff options
Diffstat (limited to 'tools/testing/selftests/bpf/test_lru_map.c')
-rw-r--r-- | tools/testing/selftests/bpf/test_lru_map.c | 646 |
1 files changed, 646 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/test_lru_map.c b/tools/testing/selftests/bpf/test_lru_map.c new file mode 100644 index 000000000..781c7de34 --- /dev/null +++ b/tools/testing/selftests/bpf/test_lru_map.c @@ -0,0 +1,646 @@ +/* + * Copyright (c) 2016 Facebook + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + */ +#define _GNU_SOURCE +#include <stdio.h> +#include <unistd.h> +#include <errno.h> +#include <string.h> +#include <assert.h> +#include <sched.h> +#include <stdlib.h> +#include <time.h> + +#include <sys/wait.h> + +#include <bpf/bpf.h> + +#include "bpf_util.h" +#include "bpf_rlimit.h" + +#define LOCAL_FREE_TARGET (128) +#define PERCPU_FREE_TARGET (4) + +static int nr_cpus; + +static int create_map(int map_type, int map_flags, unsigned int size) +{ + int map_fd; + + map_fd = bpf_create_map(map_type, sizeof(unsigned long long), + sizeof(unsigned long long), size, map_flags); + + if (map_fd == -1) + perror("bpf_create_map"); + + return map_fd; +} + +static int map_subset(int map0, int map1) +{ + unsigned long long next_key = 0; + unsigned long long value0[nr_cpus], value1[nr_cpus]; + int ret; + + while (!bpf_map_get_next_key(map1, &next_key, &next_key)) { + assert(!bpf_map_lookup_elem(map1, &next_key, value1)); + ret = bpf_map_lookup_elem(map0, &next_key, value0); + if (ret) { + printf("key:%llu not found from map. %s(%d)\n", + next_key, strerror(errno), errno); + return 0; + } + if (value0[0] != value1[0]) { + printf("key:%llu value0:%llu != value1:%llu\n", + next_key, value0[0], value1[0]); + return 0; + } + } + return 1; +} + +static int map_equal(int lru_map, int expected) +{ + return map_subset(lru_map, expected) && map_subset(expected, lru_map); +} + +static int sched_next_online(int pid, int *next_to_try) +{ + cpu_set_t cpuset; + int next = *next_to_try; + int ret = -1; + + while (next < nr_cpus) { + CPU_ZERO(&cpuset); + CPU_SET(next++, &cpuset); + if (!sched_setaffinity(pid, sizeof(cpuset), &cpuset)) { + ret = 0; + break; + } + } + + *next_to_try = next; + return ret; +} + +/* Size of the LRU amp is 2 + * Add key=1 (+1 key) + * Add key=2 (+1 key) + * Lookup Key=1 + * Add Key=3 + * => Key=2 will be removed by LRU + * Iterate map. Only found key=1 and key=3 + */ +static void test_lru_sanity0(int map_type, int map_flags) +{ + unsigned long long key, value[nr_cpus]; + int lru_map_fd, expected_map_fd; + int next_cpu = 0; + + printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type, + map_flags); + + assert(sched_next_online(0, &next_cpu) != -1); + + if (map_flags & BPF_F_NO_COMMON_LRU) + lru_map_fd = create_map(map_type, map_flags, 2 * nr_cpus); + else + lru_map_fd = create_map(map_type, map_flags, 2); + assert(lru_map_fd != -1); + + expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, 2); + assert(expected_map_fd != -1); + + value[0] = 1234; + + /* insert key=1 element */ + + key = 1; + assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST)); + assert(!bpf_map_update_elem(expected_map_fd, &key, value, + BPF_NOEXIST)); + + /* BPF_NOEXIST means: add new element if it doesn't exist */ + assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST) == -1 + /* key=1 already exists */ + && errno == EEXIST); + + assert(bpf_map_update_elem(lru_map_fd, &key, value, -1) == -1 && + errno == EINVAL); + + /* insert key=2 element */ + + /* check that key=2 is not found */ + key = 2; + assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 && + errno == ENOENT); + + /* BPF_EXIST means: update existing element */ + assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_EXIST) == -1 && + /* key=2 is not there */ + errno == ENOENT); + + assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST)); + + /* insert key=3 element */ + + /* check that key=3 is not found */ + key = 3; + assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1 && + errno == ENOENT); + + /* check that key=1 can be found and mark the ref bit to + * stop LRU from removing key=1 + */ + key = 1; + assert(!bpf_map_lookup_elem(lru_map_fd, &key, value)); + assert(value[0] == 1234); + + key = 3; + assert(!bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST)); + assert(!bpf_map_update_elem(expected_map_fd, &key, value, + BPF_NOEXIST)); + + /* key=2 has been removed from the LRU */ + key = 2; + assert(bpf_map_lookup_elem(lru_map_fd, &key, value) == -1); + + assert(map_equal(lru_map_fd, expected_map_fd)); + + close(expected_map_fd); + close(lru_map_fd); + + printf("Pass\n"); +} + +/* Size of the LRU map is 1.5*tgt_free + * Insert 1 to tgt_free (+tgt_free keys) + * Lookup 1 to tgt_free/2 + * Insert 1+tgt_free to 2*tgt_free (+tgt_free keys) + * => 1+tgt_free/2 to LOCALFREE_TARGET will be removed by LRU + */ +static void test_lru_sanity1(int map_type, int map_flags, unsigned int tgt_free) +{ + unsigned long long key, end_key, value[nr_cpus]; + int lru_map_fd, expected_map_fd; + unsigned int batch_size; + unsigned int map_size; + int next_cpu = 0; + + if (map_flags & BPF_F_NO_COMMON_LRU) + /* This test is only applicable to common LRU list */ + return; + + printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type, + map_flags); + + assert(sched_next_online(0, &next_cpu) != -1); + + batch_size = tgt_free / 2; + assert(batch_size * 2 == tgt_free); + + map_size = tgt_free + batch_size; + lru_map_fd = create_map(map_type, map_flags, map_size); + assert(lru_map_fd != -1); + + expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size); + assert(expected_map_fd != -1); + + value[0] = 1234; + + /* Insert 1 to tgt_free (+tgt_free keys) */ + end_key = 1 + tgt_free; + for (key = 1; key < end_key; key++) + assert(!bpf_map_update_elem(lru_map_fd, &key, value, + BPF_NOEXIST)); + + /* Lookup 1 to tgt_free/2 */ + end_key = 1 + batch_size; + for (key = 1; key < end_key; key++) { + assert(!bpf_map_lookup_elem(lru_map_fd, &key, value)); + assert(!bpf_map_update_elem(expected_map_fd, &key, value, + BPF_NOEXIST)); + } + + /* Insert 1+tgt_free to 2*tgt_free + * => 1+tgt_free/2 to LOCALFREE_TARGET will be + * removed by LRU + */ + key = 1 + tgt_free; + end_key = key + tgt_free; + for (; key < end_key; key++) { + assert(!bpf_map_update_elem(lru_map_fd, &key, value, + BPF_NOEXIST)); + assert(!bpf_map_update_elem(expected_map_fd, &key, value, + BPF_NOEXIST)); + } + + assert(map_equal(lru_map_fd, expected_map_fd)); + + close(expected_map_fd); + close(lru_map_fd); + + printf("Pass\n"); +} + +/* Size of the LRU map 1.5 * tgt_free + * Insert 1 to tgt_free (+tgt_free keys) + * Update 1 to tgt_free/2 + * => The original 1 to tgt_free/2 will be removed due to + * the LRU shrink process + * Re-insert 1 to tgt_free/2 again and do a lookup immeidately + * Insert 1+tgt_free to tgt_free*3/2 + * Insert 1+tgt_free*3/2 to tgt_free*5/2 + * => Key 1+tgt_free to tgt_free*3/2 + * will be removed from LRU because it has never + * been lookup and ref bit is not set + */ +static void test_lru_sanity2(int map_type, int map_flags, unsigned int tgt_free) +{ + unsigned long long key, value[nr_cpus]; + unsigned long long end_key; + int lru_map_fd, expected_map_fd; + unsigned int batch_size; + unsigned int map_size; + int next_cpu = 0; + + if (map_flags & BPF_F_NO_COMMON_LRU) + /* This test is only applicable to common LRU list */ + return; + + printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type, + map_flags); + + assert(sched_next_online(0, &next_cpu) != -1); + + batch_size = tgt_free / 2; + assert(batch_size * 2 == tgt_free); + + map_size = tgt_free + batch_size; + lru_map_fd = create_map(map_type, map_flags, map_size); + assert(lru_map_fd != -1); + + expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size); + assert(expected_map_fd != -1); + + value[0] = 1234; + + /* Insert 1 to tgt_free (+tgt_free keys) */ + end_key = 1 + tgt_free; + for (key = 1; key < end_key; key++) + assert(!bpf_map_update_elem(lru_map_fd, &key, value, + BPF_NOEXIST)); + + /* Any bpf_map_update_elem will require to acquire a new node + * from LRU first. + * + * The local list is running out of free nodes. + * It gets from the global LRU list which tries to + * shrink the inactive list to get tgt_free + * number of free nodes. + * + * Hence, the oldest key 1 to tgt_free/2 + * are removed from the LRU list. + */ + key = 1; + if (map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { + assert(!bpf_map_update_elem(lru_map_fd, &key, value, + BPF_NOEXIST)); + assert(!bpf_map_delete_elem(lru_map_fd, &key)); + } else { + assert(bpf_map_update_elem(lru_map_fd, &key, value, + BPF_EXIST)); + } + + /* Re-insert 1 to tgt_free/2 again and do a lookup + * immeidately. + */ + end_key = 1 + batch_size; + value[0] = 4321; + for (key = 1; key < end_key; key++) { + assert(bpf_map_lookup_elem(lru_map_fd, &key, value)); + assert(!bpf_map_update_elem(lru_map_fd, &key, value, + BPF_NOEXIST)); + assert(!bpf_map_lookup_elem(lru_map_fd, &key, value)); + assert(value[0] == 4321); + assert(!bpf_map_update_elem(expected_map_fd, &key, value, + BPF_NOEXIST)); + } + + value[0] = 1234; + + /* Insert 1+tgt_free to tgt_free*3/2 */ + end_key = 1 + tgt_free + batch_size; + for (key = 1 + tgt_free; key < end_key; key++) + /* These newly added but not referenced keys will be + * gone during the next LRU shrink. + */ + assert(!bpf_map_update_elem(lru_map_fd, &key, value, + BPF_NOEXIST)); + + /* Insert 1+tgt_free*3/2 to tgt_free*5/2 */ + end_key = key + tgt_free; + for (; key < end_key; key++) { + assert(!bpf_map_update_elem(lru_map_fd, &key, value, + BPF_NOEXIST)); + assert(!bpf_map_update_elem(expected_map_fd, &key, value, + BPF_NOEXIST)); + } + + assert(map_equal(lru_map_fd, expected_map_fd)); + + close(expected_map_fd); + close(lru_map_fd); + + printf("Pass\n"); +} + +/* Size of the LRU map is 2*tgt_free + * It is to test the active/inactive list rotation + * Insert 1 to 2*tgt_free (+2*tgt_free keys) + * Lookup key 1 to tgt_free*3/2 + * Add 1+2*tgt_free to tgt_free*5/2 (+tgt_free/2 keys) + * => key 1+tgt_free*3/2 to 2*tgt_free are removed from LRU + */ +static void test_lru_sanity3(int map_type, int map_flags, unsigned int tgt_free) +{ + unsigned long long key, end_key, value[nr_cpus]; + int lru_map_fd, expected_map_fd; + unsigned int batch_size; + unsigned int map_size; + int next_cpu = 0; + + if (map_flags & BPF_F_NO_COMMON_LRU) + /* This test is only applicable to common LRU list */ + return; + + printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type, + map_flags); + + assert(sched_next_online(0, &next_cpu) != -1); + + batch_size = tgt_free / 2; + assert(batch_size * 2 == tgt_free); + + map_size = tgt_free * 2; + lru_map_fd = create_map(map_type, map_flags, map_size); + assert(lru_map_fd != -1); + + expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size); + assert(expected_map_fd != -1); + + value[0] = 1234; + + /* Insert 1 to 2*tgt_free (+2*tgt_free keys) */ + end_key = 1 + (2 * tgt_free); + for (key = 1; key < end_key; key++) + assert(!bpf_map_update_elem(lru_map_fd, &key, value, + BPF_NOEXIST)); + + /* Lookup key 1 to tgt_free*3/2 */ + end_key = tgt_free + batch_size; + for (key = 1; key < end_key; key++) { + assert(!bpf_map_lookup_elem(lru_map_fd, &key, value)); + assert(!bpf_map_update_elem(expected_map_fd, &key, value, + BPF_NOEXIST)); + } + + /* Add 1+2*tgt_free to tgt_free*5/2 + * (+tgt_free/2 keys) + */ + key = 2 * tgt_free + 1; + end_key = key + batch_size; + for (; key < end_key; key++) { + assert(!bpf_map_update_elem(lru_map_fd, &key, value, + BPF_NOEXIST)); + assert(!bpf_map_update_elem(expected_map_fd, &key, value, + BPF_NOEXIST)); + } + + assert(map_equal(lru_map_fd, expected_map_fd)); + + close(expected_map_fd); + close(lru_map_fd); + + printf("Pass\n"); +} + +/* Test deletion */ +static void test_lru_sanity4(int map_type, int map_flags, unsigned int tgt_free) +{ + int lru_map_fd, expected_map_fd; + unsigned long long key, value[nr_cpus]; + unsigned long long end_key; + int next_cpu = 0; + + printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type, + map_flags); + + assert(sched_next_online(0, &next_cpu) != -1); + + if (map_flags & BPF_F_NO_COMMON_LRU) + lru_map_fd = create_map(map_type, map_flags, + 3 * tgt_free * nr_cpus); + else + lru_map_fd = create_map(map_type, map_flags, 3 * tgt_free); + assert(lru_map_fd != -1); + + expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, + 3 * tgt_free); + assert(expected_map_fd != -1); + + value[0] = 1234; + + for (key = 1; key <= 2 * tgt_free; key++) + assert(!bpf_map_update_elem(lru_map_fd, &key, value, + BPF_NOEXIST)); + + key = 1; + assert(bpf_map_update_elem(lru_map_fd, &key, value, BPF_NOEXIST)); + + for (key = 1; key <= tgt_free; key++) { + assert(!bpf_map_lookup_elem(lru_map_fd, &key, value)); + assert(!bpf_map_update_elem(expected_map_fd, &key, value, + BPF_NOEXIST)); + } + + for (; key <= 2 * tgt_free; key++) { + assert(!bpf_map_delete_elem(lru_map_fd, &key)); + assert(bpf_map_delete_elem(lru_map_fd, &key)); + } + + end_key = key + 2 * tgt_free; + for (; key < end_key; key++) { + assert(!bpf_map_update_elem(lru_map_fd, &key, value, + BPF_NOEXIST)); + assert(!bpf_map_update_elem(expected_map_fd, &key, value, + BPF_NOEXIST)); + } + + assert(map_equal(lru_map_fd, expected_map_fd)); + + close(expected_map_fd); + close(lru_map_fd); + + printf("Pass\n"); +} + +static void do_test_lru_sanity5(unsigned long long last_key, int map_fd) +{ + unsigned long long key, value[nr_cpus]; + + /* Ensure the last key inserted by previous CPU can be found */ + assert(!bpf_map_lookup_elem(map_fd, &last_key, value)); + + value[0] = 1234; + + key = last_key + 1; + assert(!bpf_map_update_elem(map_fd, &key, value, BPF_NOEXIST)); + assert(!bpf_map_lookup_elem(map_fd, &key, value)); + + /* Cannot find the last key because it was removed by LRU */ + assert(bpf_map_lookup_elem(map_fd, &last_key, value)); +} + +/* Test map with only one element */ +static void test_lru_sanity5(int map_type, int map_flags) +{ + unsigned long long key, value[nr_cpus]; + int next_cpu = 0; + int map_fd; + + if (map_flags & BPF_F_NO_COMMON_LRU) + return; + + printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type, + map_flags); + + map_fd = create_map(map_type, map_flags, 1); + assert(map_fd != -1); + + value[0] = 1234; + key = 0; + assert(!bpf_map_update_elem(map_fd, &key, value, BPF_NOEXIST)); + + while (sched_next_online(0, &next_cpu) != -1) { + pid_t pid; + + pid = fork(); + if (pid == 0) { + do_test_lru_sanity5(key, map_fd); + exit(0); + } else if (pid == -1) { + printf("couldn't spawn process to test key:%llu\n", + key); + exit(1); + } else { + int status; + + assert(waitpid(pid, &status, 0) == pid); + assert(status == 0); + key++; + } + } + + close(map_fd); + /* At least one key should be tested */ + assert(key > 0); + + printf("Pass\n"); +} + +/* Test list rotation for BPF_F_NO_COMMON_LRU map */ +static void test_lru_sanity6(int map_type, int map_flags, int tgt_free) +{ + int lru_map_fd, expected_map_fd; + unsigned long long key, value[nr_cpus]; + unsigned int map_size = tgt_free * 2; + int next_cpu = 0; + + if (!(map_flags & BPF_F_NO_COMMON_LRU)) + return; + + printf("%s (map_type:%d map_flags:0x%X): ", __func__, map_type, + map_flags); + + assert(sched_next_online(0, &next_cpu) != -1); + + expected_map_fd = create_map(BPF_MAP_TYPE_HASH, 0, map_size); + assert(expected_map_fd != -1); + + lru_map_fd = create_map(map_type, map_flags, map_size * nr_cpus); + assert(lru_map_fd != -1); + + value[0] = 1234; + + for (key = 1; key <= tgt_free; key++) { + assert(!bpf_map_update_elem(lru_map_fd, &key, value, + BPF_NOEXIST)); + assert(!bpf_map_update_elem(expected_map_fd, &key, value, + BPF_NOEXIST)); + } + + for (; key <= tgt_free * 2; key++) { + unsigned long long stable_key; + + /* Make ref bit sticky for key: [1, tgt_free] */ + for (stable_key = 1; stable_key <= tgt_free; stable_key++) { + /* Mark the ref bit */ + assert(!bpf_map_lookup_elem(lru_map_fd, &stable_key, + value)); + } + assert(!bpf_map_update_elem(lru_map_fd, &key, value, + BPF_NOEXIST)); + } + + for (; key <= tgt_free * 3; key++) { + assert(!bpf_map_update_elem(lru_map_fd, &key, value, + BPF_NOEXIST)); + assert(!bpf_map_update_elem(expected_map_fd, &key, value, + BPF_NOEXIST)); + } + + assert(map_equal(lru_map_fd, expected_map_fd)); + + close(expected_map_fd); + close(lru_map_fd); + + printf("Pass\n"); +} + +int main(int argc, char **argv) +{ + int map_types[] = {BPF_MAP_TYPE_LRU_HASH, + BPF_MAP_TYPE_LRU_PERCPU_HASH}; + int map_flags[] = {0, BPF_F_NO_COMMON_LRU}; + int t, f; + + setbuf(stdout, NULL); + + nr_cpus = bpf_num_possible_cpus(); + assert(nr_cpus != -1); + printf("nr_cpus:%d\n\n", nr_cpus); + + for (f = 0; f < sizeof(map_flags) / sizeof(*map_flags); f++) { + unsigned int tgt_free = (map_flags[f] & BPF_F_NO_COMMON_LRU) ? + PERCPU_FREE_TARGET : LOCAL_FREE_TARGET; + + for (t = 0; t < sizeof(map_types) / sizeof(*map_types); t++) { + test_lru_sanity0(map_types[t], map_flags[f]); + test_lru_sanity1(map_types[t], map_flags[f], tgt_free); + test_lru_sanity2(map_types[t], map_flags[f], tgt_free); + test_lru_sanity3(map_types[t], map_flags[f], tgt_free); + test_lru_sanity4(map_types[t], map_flags[f], tgt_free); + test_lru_sanity5(map_types[t], map_flags[f]); + test_lru_sanity6(map_types[t], map_flags[f], tgt_free); + + printf("\n"); + } + } + + return 0; +} |