1// SPDX-License-Identifier: GPL-2.0
2/* Copyright Amazon.com Inc. or its affiliates. */
3#define _GNU_SOURCE
4#include <sched.h>
5
6#include <fcntl.h>
7
8#include <netinet/in.h>
9#include <sys/socket.h>
10#include <sys/sysinfo.h>
11
12#include "../kselftest_harness.h"
13
14FIXTURE(so_incoming_cpu)
15{
16 int *servers;
17 union {
18 struct sockaddr addr;
19 struct sockaddr_in in_addr;
20 };
21 socklen_t addrlen;
22};
23
24enum when_to_set {
25 BEFORE_REUSEPORT,
26 BEFORE_LISTEN,
27 AFTER_LISTEN,
28 AFTER_ALL_LISTEN,
29};
30
31FIXTURE_VARIANT(so_incoming_cpu)
32{
33 int when_to_set;
34};
35
36FIXTURE_VARIANT_ADD(so_incoming_cpu, before_reuseport)
37{
38 .when_to_set = BEFORE_REUSEPORT,
39};
40
41FIXTURE_VARIANT_ADD(so_incoming_cpu, before_listen)
42{
43 .when_to_set = BEFORE_LISTEN,
44};
45
46FIXTURE_VARIANT_ADD(so_incoming_cpu, after_listen)
47{
48 .when_to_set = AFTER_LISTEN,
49};
50
51FIXTURE_VARIANT_ADD(so_incoming_cpu, after_all_listen)
52{
53 .when_to_set = AFTER_ALL_LISTEN,
54};
55
56static void write_sysctl(struct __test_metadata *_metadata,
57 char *filename, char *string)
58{
59 int fd, len, ret;
60
61 fd = open(filename, O_WRONLY);
62 ASSERT_NE(fd, -1);
63
64 len = strlen(string);
65 ret = write(fd, string, len);
66 ASSERT_EQ(ret, len);
67}
68
69static void setup_netns(struct __test_metadata *_metadata)
70{
71 ASSERT_EQ(unshare(CLONE_NEWNET), 0);
72 ASSERT_EQ(system("ip link set lo up"), 0);
73
74 write_sysctl(_metadata, filename: "/proc/sys/net/ipv4/ip_local_port_range", string: "10000 60001");
75 write_sysctl(_metadata, filename: "/proc/sys/net/ipv4/tcp_tw_reuse", string: "0");
76}
77
78#define NR_PORT (60001 - 10000 - 1)
79#define NR_CLIENT_PER_SERVER_DEFAULT 32
80static int nr_client_per_server, nr_server, nr_client;
81
82FIXTURE_SETUP(so_incoming_cpu)
83{
84 setup_netns(_metadata);
85
86 nr_server = get_nprocs();
87 ASSERT_LE(2, nr_server);
88
89 if (NR_CLIENT_PER_SERVER_DEFAULT * nr_server < NR_PORT)
90 nr_client_per_server = NR_CLIENT_PER_SERVER_DEFAULT;
91 else
92 nr_client_per_server = NR_PORT / nr_server;
93
94 nr_client = nr_client_per_server * nr_server;
95
96 self->servers = malloc(sizeof(int) * nr_server);
97 ASSERT_NE(self->servers, NULL);
98
99 self->in_addr.sin_family = AF_INET;
100 self->in_addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
101 self->in_addr.sin_port = htons(0);
102 self->addrlen = sizeof(struct sockaddr_in);
103}
104
105FIXTURE_TEARDOWN(so_incoming_cpu)
106{
107 int i;
108
109 for (i = 0; i < nr_server; i++)
110 close(self->servers[i]);
111
112 free(self->servers);
113}
114
115void set_so_incoming_cpu(struct __test_metadata *_metadata, int fd, int cpu)
116{
117 int ret;
118
119 ret = setsockopt(fd, SOL_SOCKET, SO_INCOMING_CPU, &cpu, sizeof(int));
120 ASSERT_EQ(ret, 0);
121}
122
123int create_server(struct __test_metadata *_metadata,
124 FIXTURE_DATA(so_incoming_cpu) *self,
125 const FIXTURE_VARIANT(so_incoming_cpu) *variant,
126 int cpu)
127{
128 int fd, ret;
129
130 fd = socket(AF_INET, SOCK_STREAM | SOCK_NONBLOCK, 0);
131 ASSERT_NE(fd, -1);
132
133 if (variant->when_to_set == BEFORE_REUSEPORT)
134 set_so_incoming_cpu(_metadata, fd, cpu);
135
136 ret = setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &(int){1}, sizeof(int));
137 ASSERT_EQ(ret, 0);
138
139 ret = bind(fd, &self->addr, self->addrlen);
140 ASSERT_EQ(ret, 0);
141
142 if (variant->when_to_set == BEFORE_LISTEN)
143 set_so_incoming_cpu(_metadata, fd, cpu);
144
145 /* We don't use nr_client_per_server here not to block
146 * this test at connect() if SO_INCOMING_CPU is broken.
147 */
148 ret = listen(fd, nr_client);
149 ASSERT_EQ(ret, 0);
150
151 if (variant->when_to_set == AFTER_LISTEN)
152 set_so_incoming_cpu(_metadata, fd, cpu);
153
154 return fd;
155}
156
157void create_servers(struct __test_metadata *_metadata,
158 FIXTURE_DATA(so_incoming_cpu) *self,
159 const FIXTURE_VARIANT(so_incoming_cpu) *variant)
160{
161 int i, ret;
162
163 for (i = 0; i < nr_server; i++) {
164 self->servers[i] = create_server(_metadata, self, variant, cpu: i);
165
166 if (i == 0) {
167 ret = getsockname(self->servers[i], &self->addr, &self->addrlen);
168 ASSERT_EQ(ret, 0);
169 }
170 }
171
172 if (variant->when_to_set == AFTER_ALL_LISTEN) {
173 for (i = 0; i < nr_server; i++)
174 set_so_incoming_cpu(_metadata, fd: self->servers[i], cpu: i);
175 }
176}
177
178void create_clients(struct __test_metadata *_metadata,
179 FIXTURE_DATA(so_incoming_cpu) *self)
180{
181 cpu_set_t cpu_set;
182 int i, j, fd, ret;
183
184 for (i = 0; i < nr_server; i++) {
185 CPU_ZERO(&cpu_set);
186
187 CPU_SET(i, &cpu_set);
188 ASSERT_EQ(CPU_COUNT(&cpu_set), 1);
189 ASSERT_NE(CPU_ISSET(i, &cpu_set), 0);
190
191 /* Make sure SYN will be processed on the i-th CPU
192 * and finally distributed to the i-th listener.
193 */
194 ret = sched_setaffinity(0, sizeof(cpu_set), &cpu_set);
195 ASSERT_EQ(ret, 0);
196
197 for (j = 0; j < nr_client_per_server; j++) {
198 fd = socket(AF_INET, SOCK_STREAM, 0);
199 ASSERT_NE(fd, -1);
200
201 ret = connect(fd, &self->addr, self->addrlen);
202 ASSERT_EQ(ret, 0);
203
204 close(fd);
205 }
206 }
207}
208
209void verify_incoming_cpu(struct __test_metadata *_metadata,
210 FIXTURE_DATA(so_incoming_cpu) *self)
211{
212 int i, j, fd, cpu, ret, total = 0;
213 socklen_t len = sizeof(int);
214
215 for (i = 0; i < nr_server; i++) {
216 for (j = 0; j < nr_client_per_server; j++) {
217 /* If we see -EAGAIN here, SO_INCOMING_CPU is broken */
218 fd = accept(self->servers[i], &self->addr, &self->addrlen);
219 ASSERT_NE(fd, -1);
220
221 ret = getsockopt(fd, SOL_SOCKET, SO_INCOMING_CPU, &cpu, &len);
222 ASSERT_EQ(ret, 0);
223 ASSERT_EQ(cpu, i);
224
225 close(fd);
226 total++;
227 }
228 }
229
230 ASSERT_EQ(total, nr_client);
231 TH_LOG("SO_INCOMING_CPU is very likely to be "
232 "working correctly with %d sockets.", total);
233}
234
235TEST_F(so_incoming_cpu, test1)
236{
237 create_servers(_metadata, self, variant);
238 create_clients(_metadata, self);
239 verify_incoming_cpu(_metadata, self);
240}
241
242TEST_F(so_incoming_cpu, test2)
243{
244 int server;
245
246 create_servers(_metadata, self, variant);
247
248 /* No CPU specified */
249 server = create_server(_metadata, self, variant, cpu: -1);
250 close(server);
251
252 create_clients(_metadata, self);
253 verify_incoming_cpu(_metadata, self);
254}
255
256TEST_F(so_incoming_cpu, test3)
257{
258 int server, client;
259
260 create_servers(_metadata, self, variant);
261
262 /* No CPU specified */
263 server = create_server(_metadata, self, variant, cpu: -1);
264
265 create_clients(_metadata, self);
266
267 /* Never receive any requests */
268 client = accept(server, &self->addr, &self->addrlen);
269 ASSERT_EQ(client, -1);
270
271 verify_incoming_cpu(_metadata, self);
272}
273
274TEST_HARNESS_MAIN
275

source code of linux/tools/testing/selftests/net/so_incoming_cpu.c