1// SPDX-License-Identifier: GPL-2.0-only
  2/* Copyright (c) 2020 Tessares SA <http://www.tessares.net> */
  3
  4#include <test_progs.h>
  5#include "test_map_init.skel.h"
  6
  7#define TEST_VALUE 0x1234
  8#define FILL_VALUE 0xdeadbeef
  9
 10static int nr_cpus;
 11static int duration;
 12
 13typedef unsigned long long map_key_t;
 14typedef unsigned long long map_value_t;
 15typedef struct {
 16	map_value_t v; /* padding */
 17} __bpf_percpu_val_align pcpu_map_value_t;
 18
 19
 20static int map_populate(int map_fd, int num)
 21{
 22	pcpu_map_value_t value[nr_cpus];
 23	int i, err;
 24	map_key_t key;
 25
 26	for (i = 0; i < nr_cpus; i++)
 27		bpf_percpu(value, i) = FILL_VALUE;
 28
 29	for (key = 1; key <= num; key++) {
 30		err = bpf_map_update_elem(map_fd, &key, value, BPF_NOEXIST);
 31		if (!ASSERT_OK(err, "bpf_map_update_elem"))
 32			return -1;
 33	}
 34
 35	return 0;
 36}
 37
 38static struct test_map_init *setup(enum bpf_map_type map_type, int map_sz,
 39			    int *map_fd, int populate)
 40{
 41	struct test_map_init *skel;
 42	int err;
 43
 44	skel = test_map_init__open();
 45	if (!ASSERT_OK_PTR(skel, "skel_open"))
 46		return NULL;
 47
 48	err = bpf_map__set_type(skel->maps.hashmap1, map_type);
 49	if (!ASSERT_OK(err, "bpf_map__set_type"))
 50		goto error;
 51
 52	err = bpf_map__set_max_entries(skel->maps.hashmap1, map_sz);
 53	if (!ASSERT_OK(err, "bpf_map__set_max_entries"))
 54		goto error;
 55
 56	err = test_map_init__load(skel);
 57	if (!ASSERT_OK(err, "skel_load"))
 58		goto error;
 59
 60	*map_fd = bpf_map__fd(skel->maps.hashmap1);
 61	if (CHECK(*map_fd < 0, "bpf_map__fd", "failed\n"))
 62		goto error;
 63
 64	err = map_populate(*map_fd, populate);
 65	if (!ASSERT_OK(err, "map_populate"))
 66		goto error_map;
 67
 68	return skel;
 69
 70error_map:
 71	close(*map_fd);
 72error:
 73	test_map_init__destroy(skel);
 74	return NULL;
 75}
 76
 77/* executes bpf program that updates map with key, value */
 78static int prog_run_insert_elem(struct test_map_init *skel, map_key_t key,
 79				map_value_t value)
 80{
 81	struct test_map_init__bss *bss;
 82
 83	bss = skel->bss;
 84
 85	bss->inKey = key;
 86	bss->inValue = value;
 87	bss->inPid = getpid();
 88
 89	if (!ASSERT_OK(test_map_init__attach(skel), "skel_attach"))
 90		return -1;
 91
 92	/* Let tracepoint trigger */
 93	syscall(__NR_getpgid);
 94
 95	test_map_init__detach(skel);
 96
 97	return 0;
 98}
 99
100static int check_values_one_cpu(pcpu_map_value_t *value, map_value_t expected)
101{
102	int i, nzCnt = 0;
103	map_value_t val;
104
105	for (i = 0; i < nr_cpus; i++) {
106		val = bpf_percpu(value, i);
107		if (val) {
108			if (CHECK(val != expected, "map value",
109				  "unexpected for cpu %d: 0x%llx\n", i, val))
110				return -1;
111			nzCnt++;
112		}
113	}
114
115	if (CHECK(nzCnt != 1, "map value", "set for %d CPUs instead of 1!\n",
116		  nzCnt))
117		return -1;
118
119	return 0;
120}
121
122/* Add key=1 elem with values set for all CPUs
123 * Delete elem key=1
124 * Run bpf prog that inserts new key=1 elem with value=0x1234
125 *   (bpf prog can only set value for current CPU)
126 * Lookup Key=1 and check value is as expected for all CPUs:
127 *   value set by bpf prog for one CPU, 0 for all others
128 */
129static void test_pcpu_map_init(void)
130{
131	pcpu_map_value_t value[nr_cpus];
132	struct test_map_init *skel;
133	int map_fd, err;
134	map_key_t key;
135
136	/* max 1 elem in map so insertion is forced to reuse freed entry */
137	skel = setup(BPF_MAP_TYPE_PERCPU_HASH, 1, &map_fd, 1);
138	if (!ASSERT_OK_PTR(skel, "prog_setup"))
139		return;
140
141	/* delete element so the entry can be re-used*/
142	key = 1;
143	err = bpf_map_delete_elem(map_fd, &key);
144	if (!ASSERT_OK(err, "bpf_map_delete_elem"))
145		goto cleanup;
146
147	/* run bpf prog that inserts new elem, re-using the slot just freed */
148	err = prog_run_insert_elem(skel, key, TEST_VALUE);
149	if (!ASSERT_OK(err, "prog_run_insert_elem"))
150		goto cleanup;
151
152	/* check that key=1 was re-created by bpf prog */
153	err = bpf_map_lookup_elem(map_fd, &key, value);
154	if (!ASSERT_OK(err, "bpf_map_lookup_elem"))
155		goto cleanup;
156
157	/* and has expected values */
158	check_values_one_cpu(value, TEST_VALUE);
159
160cleanup:
161	test_map_init__destroy(skel);
162}
163
164/* Add key=1 and key=2 elems with values set for all CPUs
165 * Run bpf prog that inserts new key=3 elem
166 *   (only for current cpu; other cpus should have initial value = 0)
167 * Lookup Key=1 and check value is as expected for all CPUs
168 */
169static void test_pcpu_lru_map_init(void)
170{
171	pcpu_map_value_t value[nr_cpus];
172	struct test_map_init *skel;
173	int map_fd, err;
174	map_key_t key;
175
176	/* Set up LRU map with 2 elements, values filled for all CPUs.
177	 * With these 2 elements, the LRU map is full
178	 */
179	skel = setup(BPF_MAP_TYPE_LRU_PERCPU_HASH, 2, &map_fd, 2);
180	if (!ASSERT_OK_PTR(skel, "prog_setup"))
181		return;
182
183	/* run bpf prog that inserts new key=3 element, re-using LRU slot */
184	key = 3;
185	err = prog_run_insert_elem(skel, key, TEST_VALUE);
186	if (!ASSERT_OK(err, "prog_run_insert_elem"))
187		goto cleanup;
188
189	/* check that key=3 replaced one of earlier elements */
190	err = bpf_map_lookup_elem(map_fd, &key, value);
191	if (!ASSERT_OK(err, "bpf_map_lookup_elem"))
192		goto cleanup;
193
194	/* and has expected values */
195	check_values_one_cpu(value, TEST_VALUE);
196
197cleanup:
198	test_map_init__destroy(skel);
199}
200
201void test_map_init(void)
202{
203	nr_cpus = bpf_num_possible_cpus();
204	if (nr_cpus <= 1) {
205		printf("%s:SKIP: >1 cpu needed for this test\n", __func__);
206		test__skip();
207		return;
208	}
209
210	if (test__start_subtest("pcpu_map_init"))
211		test_pcpu_map_init();
212	if (test__start_subtest("pcpu_lru_map_init"))
213		test_pcpu_lru_map_init();
214}