lib/librte_telemetry/telemetry.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2020 Intel Corporation
   3  */
   4
   5 #ifndef RTE_EXEC_ENV_WINDOWS
   6 #include <unistd.h>
   7 #include <pthread.h>
   8 #include <sys/socket.h>
   9 #include <sys/un.h>
  10 #include <dlfcn.h>
  11 #endif /* !RTE_EXEC_ENV_WINDOWS */
  12
  13 /* we won't link against libbsd, so just always use DPDKs-specific strlcpy */
  14 #undef RTE_USE_LIBBSD
  15 #include <rte_string_fns.h>
  16 #include <rte_common.h>
  17 #include <rte_spinlock.h>
  18 #include <rte_version.h>
  19
  20 #include "rte_telemetry.h"
  21 #include "telemetry_json.h"
  22 #include "telemetry_data.h"
  23 #include "rte_telemetry_legacy.h"
  24
  25 #define MAX_CMD_LEN 56
  26 #define MAX_HELP_LEN 64
  27 #define MAX_OUTPUT_LEN (1024 * 16)
  28 #define MAX_CONNECTIONS 10
  29
  30 #ifndef RTE_EXEC_ENV_WINDOWS
  31 static void *
  32 client_handler(void *socket);
  33 #endif /* !RTE_EXEC_ENV_WINDOWS */
  34
  35 struct cmd_callback {
  36         char cmd[MAX_CMD_LEN];
  37         telemetry_cb fn;
  38         char help[MAX_HELP_LEN];
  39 };
  40
  41 #ifndef RTE_EXEC_ENV_WINDOWS
  42 struct socket {
  43         int sock;
  44         char path[sizeof(((struct sockaddr_un *)0)->sun_path)];
  45         handler fn;
  46         uint16_t *num_clients;
  47 };
  48 static struct socket v2_socket; /* socket for v2 telemetry */
  49 static struct socket v1_socket; /* socket for v1 telemetry */
  50 #endif /* !RTE_EXEC_ENV_WINDOWS */
  51 static char telemetry_log_error[1024]; /* Will contain error on init failure */
  52 /* list of command callbacks, with one command registered by default */
  53 static struct cmd_callback callbacks[TELEMETRY_MAX_CALLBACKS];
  54 static int num_callbacks; /* How many commands are registered */
  55 /* Used when accessing or modifying list of command callbacks */
  56 static rte_spinlock_t callback_sl = RTE_SPINLOCK_INITIALIZER;
  57 #ifndef RTE_EXEC_ENV_WINDOWS
  58 static uint16_t v2_clients;
  59 #endif /* !RTE_EXEC_ENV_WINDOWS */
  60
  61 int
  62 rte_telemetry_register_cmd(const char *cmd, telemetry_cb fn, const char *help)
  63 {
  64         int i = 0;
  65
  66         if (strlen(cmd) >= MAX_CMD_LEN || fn == NULL || cmd[0] != '/'
  67                         || strlen(help) >= MAX_HELP_LEN)
  68                 return -EINVAL;
  69         if (num_callbacks >= TELEMETRY_MAX_CALLBACKS)
  70                 return -ENOENT;
  71
  72         rte_spinlock_lock(&callback_sl);
  73         while (i < num_callbacks && strcmp(cmd, callbacks[i].cmd) > 0)
  74                 i++;
  75         if (i != num_callbacks)
  76                 /* Move elements to keep the list alphabetical */
  77                 memmove(callbacks + i + 1, callbacks + i,
  78                         sizeof(struct cmd_callback) * (num_callbacks - i));
  79
  80         strlcpy(callbacks[i].cmd, cmd, MAX_CMD_LEN);
  81         callbacks[i].fn = fn;
  82         strlcpy(callbacks[i].help, help, MAX_HELP_LEN);
  83         num_callbacks++;
  84         rte_spinlock_unlock(&callback_sl);
  85
  86         return 0;
  87 }
  88
  89 #ifndef RTE_EXEC_ENV_WINDOWS
  90
  91 static int
  92 list_commands(const char *cmd __rte_unused, const char *params __rte_unused,
  93                 struct rte_tel_data *d)
  94 {
  95         int i;
  96
  97         rte_tel_data_start_array(d, RTE_TEL_STRING_VAL);
  98         for (i = 0; i < num_callbacks; i++)
  99                 rte_tel_data_add_array_string(d, callbacks[i].cmd);
 100         return 0;
 101 }
 102
 103 static int
 104 json_info(const char *cmd __rte_unused, const char *params __rte_unused,
 105                 struct rte_tel_data *d)
 106 {
 107         rte_tel_data_start_dict(d);
 108         rte_tel_data_add_dict_string(d, "version", rte_version());
 109         rte_tel_data_add_dict_int(d, "pid", getpid());
 110         rte_tel_data_add_dict_int(d, "max_output_len", MAX_OUTPUT_LEN);
 111         return 0;
 112 }
 113
 114 static int
 115 command_help(const char *cmd __rte_unused, const char *params,
 116                 struct rte_tel_data *d)
 117 {
 118         int i;
 119
 120         if (!params)
 121                 return -1;
 122         rte_tel_data_start_dict(d);
 123         rte_spinlock_lock(&callback_sl);
 124         for (i = 0; i < num_callbacks; i++)
 125                 if (strcmp(params, callbacks[i].cmd) == 0) {
 126                         rte_tel_data_add_dict_string(d, params,
 127                                         callbacks[i].help);
 128                         break;
 129                 }
 130         rte_spinlock_unlock(&callback_sl);
 131         if (i == num_callbacks)
 132                 return -1;
 133         return 0;
 134 }
 135
 136 static void
 137 output_json(const char *cmd, const struct rte_tel_data *d, int s)
 138 {
 139         char out_buf[MAX_OUTPUT_LEN];
 140
 141         char *cb_data_buf;
 142         size_t buf_len, prefix_used, used = 0;
 143         unsigned int i;
 144
 145         RTE_BUILD_BUG_ON(sizeof(out_buf) < MAX_CMD_LEN +
 146                         RTE_TEL_MAX_SINGLE_STRING_LEN + 10);
 147         switch (d->type) {
 148         case RTE_TEL_NULL:
 149                 used = snprintf(out_buf, sizeof(out_buf), "{\"%.*s\":null}",
 150                                 MAX_CMD_LEN, cmd ? cmd : "none");
 151                 break;
 152         case RTE_TEL_STRING:
 153                 used = snprintf(out_buf, sizeof(out_buf), "{\"%.*s\":\"%.*s\"}",
 154                                 MAX_CMD_LEN, cmd,
 155                                 RTE_TEL_MAX_SINGLE_STRING_LEN, d->data.str);
 156                 break;
 157         case RTE_TEL_DICT:
 158                 prefix_used = snprintf(out_buf, sizeof(out_buf), "{\"%.*s\":",
 159                                 MAX_CMD_LEN, cmd);
 160                 cb_data_buf = &out_buf[prefix_used];
 161                 buf_len = sizeof(out_buf) - prefix_used - 1; /* space for '}' */
 162
 163                 used = rte_tel_json_empty_obj(cb_data_buf, buf_len, 0);
 164                 for (i = 0; i < d->data_len; i++) {
 165                         const struct tel_dict_entry *v = &d->data.dict[i];
 166                         switch (v->type) {
 167                         case RTE_TEL_STRING_VAL:
 168                                 used = rte_tel_json_add_obj_str(cb_data_buf,
 169                                                 buf_len, used,
 170                                                 v->name, v->value.sval);
 171                                 break;
 172                         case RTE_TEL_INT_VAL:
 173                                 used = rte_tel_json_add_obj_int(cb_data_buf,
 174                                                 buf_len, used,
 175                                                 v->name, v->value.ival);
 176                                 break;
 177                         case RTE_TEL_U64_VAL:
 178                                 used = rte_tel_json_add_obj_u64(cb_data_buf,
 179                                                 buf_len, used,
 180                                                 v->name, v->value.u64val);
 181                                 break;
 182                         }
 183                 }
 184                 used += prefix_used;
 185                 used += strlcat(out_buf + used, "}", sizeof(out_buf) - used);
 186                 break;
 187         case RTE_TEL_ARRAY_STRING:
 188         case RTE_TEL_ARRAY_INT:
 189         case RTE_TEL_ARRAY_U64:
 190                 prefix_used = snprintf(out_buf, sizeof(out_buf), "{\"%.*s\":",
 191                                 MAX_CMD_LEN, cmd);
 192                 cb_data_buf = &out_buf[prefix_used];
 193                 buf_len = sizeof(out_buf) - prefix_used - 1; /* space for '}' */
 194
 195                 used = rte_tel_json_empty_array(cb_data_buf, buf_len, 0);
 196                 for (i = 0; i < d->data_len; i++)
 197                         if (d->type == RTE_TEL_ARRAY_STRING)
 198                                 used = rte_tel_json_add_array_string(
 199                                                 cb_data_buf,
 200                                                 buf_len, used,
 201                                                 d->data.array[i].sval);
 202                         else if (d->type == RTE_TEL_ARRAY_INT)
 203                                 used = rte_tel_json_add_array_int(cb_data_buf,
 204                                                 buf_len, used,
 205                                                 d->data.array[i].ival);
 206                         else if (d->type == RTE_TEL_ARRAY_U64)
 207                                 used = rte_tel_json_add_array_u64(cb_data_buf,
 208                                                 buf_len, used,
 209                                                 d->data.array[i].u64val);
 210                 used += prefix_used;
 211                 used += strlcat(out_buf + used, "}", sizeof(out_buf) - used);
 212                 break;
 213         }
 214         if (write(s, out_buf, used) < 0)
 215                 perror("Error writing to socket");
 216 }
 217
 218 static void
 219 perform_command(telemetry_cb fn, const char *cmd, const char *param, int s)
 220 {
 221         struct rte_tel_data data;
 222
 223         int ret = fn(cmd, param, &data);
 224         if (ret < 0) {
 225                 char out_buf[MAX_CMD_LEN + 10];
 226                 int used = snprintf(out_buf, sizeof(out_buf), "{\"%.*s\":null}",
 227                                 MAX_CMD_LEN, cmd ? cmd : "none");
 228                 if (write(s, out_buf, used) < 0)
 229                         perror("Error writing to socket");
 230                 return;
 231         }
 232         output_json(cmd, &data, s);
 233 }
 234
 235 static int
 236 unknown_command(const char *cmd __rte_unused, const char *params __rte_unused,
 237                 struct rte_tel_data *d)
 238 {
 239         return d->type = RTE_TEL_NULL;
 240 }
 241
 242 static void *
 243 client_handler(void *sock_id)
 244 {
 245         int s = (int)(uintptr_t)sock_id;
 246         char buffer[1024];
 247         char info_str[1024];
 248         snprintf(info_str, sizeof(info_str),
 249                         "{\"version\":\"%s\",\"pid\":%d,\"max_output_len\":%d}",
 250                         rte_version(), getpid(), MAX_OUTPUT_LEN);
 251         if (write(s, info_str, strlen(info_str)) < 0) {
 252                 close(s);
 253                 return NULL;
 254         }
 255
 256         /* receive data is not null terminated */
 257         int bytes = read(s, buffer, sizeof(buffer) - 1);
 258         while (bytes > 0) {
 259                 buffer[bytes] = 0;
 260                 const char *cmd = strtok(buffer, ",");
 261                 const char *param = strtok(NULL, ",");
 262                 telemetry_cb fn = unknown_command;
 263                 int i;
 264
 265                 if (cmd && strlen(cmd) < MAX_CMD_LEN) {
 266                         rte_spinlock_lock(&callback_sl);
 267                         for (i = 0; i < num_callbacks; i++)
 268                                 if (strcmp(cmd, callbacks[i].cmd) == 0) {
 269                                         fn = callbacks[i].fn;
 270                                         break;
 271                                 }
 272                         rte_spinlock_unlock(&callback_sl);
 273                 }
 274                 perform_command(fn, cmd, param, s);
 275
 276                 bytes = read(s, buffer, sizeof(buffer) - 1);
 277         }
 278         close(s);
 279         __atomic_sub_fetch(&v2_clients, 1, __ATOMIC_RELAXED);
 280         return NULL;
 281 }
 282
 283 static void *
 284 socket_listener(void *socket)
 285 {
 286         while (1) {
 287                 pthread_t th;
 288                 struct socket *s = (struct socket *)socket;
 289                 int s_accepted = accept(s->sock, NULL, NULL);
 290                 if (s_accepted < 0) {
 291                         snprintf(telemetry_log_error,
 292                                 sizeof(telemetry_log_error),
 293                                 "Error with accept, telemetry thread quitting");
 294                         return NULL;
 295                 }
 296                 if (s->num_clients != NULL) {
 297                         uint16_t conns = __atomic_load_n(s->num_clients,
 298                                         __ATOMIC_RELAXED);
 299                         if (conns >= MAX_CONNECTIONS) {
 300                                 close(s_accepted);
 301                                 continue;
 302                         }
 303                         __atomic_add_fetch(s->num_clients, 1,
 304                                         __ATOMIC_RELAXED);
 305                 }
 306                 pthread_create(&th, NULL, s->fn, (void *)(uintptr_t)s_accepted);
 307                 pthread_detach(th);
 308         }
 309         return NULL;
 310 }
 311
 312 static inline char *
 313 get_socket_path(const char *runtime_dir, const int version)
 314 {
 315         static char path[PATH_MAX];
 316         snprintf(path, sizeof(path), "%s/dpdk_telemetry.v%d",
 317                         strlen(runtime_dir) ? runtime_dir : "/tmp", version);
 318         return path;
 319 }
 320
 321 static void
 322 unlink_sockets(void)
 323 {
 324         if (v2_socket.path[0])
 325                 unlink(v2_socket.path);
 326         if (v1_socket.path[0])
 327                 unlink(v1_socket.path);
 328 }
 329
 330 static int
 331 create_socket(char *path)
 332 {
 333         int sock = socket(AF_UNIX, SOCK_SEQPACKET, 0);
 334         if (sock < 0) {
 335                 snprintf(telemetry_log_error, sizeof(telemetry_log_error),
 336                                 "Error with socket creation, %s",
 337                                 strerror(errno));
 338                 return -1;
 339         }
 340
 341         struct sockaddr_un sun = {.sun_family = AF_UNIX};
 342         strlcpy(sun.sun_path, path, sizeof(sun.sun_path));
 343         unlink(sun.sun_path);
 344         if (bind(sock, (void *) &sun, sizeof(sun)) < 0) {
 345                 snprintf(telemetry_log_error, sizeof(telemetry_log_error),
 346                                 "Error binding socket: %s",
 347                                 strerror(errno));
 348                 sun.sun_path[0] = 0;
 349                 goto error;
 350         }
 351
 352         if (listen(sock, 1) < 0) {
 353                 snprintf(telemetry_log_error, sizeof(telemetry_log_error),
 354                                 "Error calling listen for socket: %s",
 355                                 strerror(errno));
 356                 goto error;
 357         }
 358
 359         return sock;
 360
 361 error:
 362         close(sock);
 363         unlink_sockets();
 364         return -1;
 365 }
 366
 367 static int
 368 telemetry_legacy_init(const char *runtime_dir, rte_cpuset_t *cpuset)
 369 {
 370         pthread_t t_old;
 371
 372         if (num_legacy_callbacks == 1) {
 373                 snprintf(telemetry_log_error, sizeof(telemetry_log_error),
 374                          "No legacy callbacks, legacy socket not created");
 375                 return -1;
 376         }
 377
 378         v1_socket.fn = legacy_client_handler;
 379         if ((size_t) snprintf(v1_socket.path, sizeof(v1_socket.path),
 380                         "%s/telemetry", runtime_dir)
 381                         >= sizeof(v1_socket.path)) {
 382                 snprintf(telemetry_log_error, sizeof(telemetry_log_error),
 383                                 "Error with socket binding, path too long");
 384                 return -1;
 385         }
 386         v1_socket.sock = create_socket(v1_socket.path);
 387         if (v1_socket.sock < 0)
 388                 return -1;
 389         pthread_create(&t_old, NULL, socket_listener, &v1_socket);
 390         pthread_setaffinity_np(t_old, sizeof(*cpuset), cpuset);
 391
 392         return 0;
 393 }
 394
 395 static int
 396 telemetry_v2_init(const char *runtime_dir, rte_cpuset_t *cpuset)
 397 {
 398         pthread_t t_new;
 399
 400         v2_socket.num_clients = &v2_clients;
 401         rte_telemetry_register_cmd("/", list_commands,
 402                         "Returns list of available commands, Takes no parameters");
 403         rte_telemetry_register_cmd("/info", json_info,
 404                         "Returns DPDK Telemetry information. Takes no parameters");
 405         rte_telemetry_register_cmd("/help", command_help,
 406                         "Returns help text for a command. Parameters: string command");
 407         v2_socket.fn = client_handler;
 408         if (strlcpy(v2_socket.path, get_socket_path(runtime_dir, 2),
 409                         sizeof(v2_socket.path)) >= sizeof(v2_socket.path)) {
 410                 snprintf(telemetry_log_error, sizeof(telemetry_log_error),
 411                                 "Error with socket binding, path too long");
 412                 return -1;
 413         }
 414
 415         v2_socket.sock = create_socket(v2_socket.path);
 416         if (v2_socket.sock < 0)
 417                 return -1;
 418         pthread_create(&t_new, NULL, socket_listener, &v2_socket);
 419         pthread_setaffinity_np(t_new, sizeof(*cpuset), cpuset);
 420         atexit(unlink_sockets);
 421
 422         return 0;
 423 }
 424
 425 #endif /* !RTE_EXEC_ENV_WINDOWS */
 426
 427 int32_t
 428 rte_telemetry_init(const char *runtime_dir, rte_cpuset_t *cpuset,
 429                 const char **err_str)
 430 {
 431 #ifndef RTE_EXEC_ENV_WINDOWS
 432         if (telemetry_v2_init(runtime_dir, cpuset) != 0) {
 433                 *err_str = telemetry_log_error;
 434                 return -1;
 435         }
 436         if (telemetry_legacy_init(runtime_dir, cpuset) != 0) {
 437                 *err_str = telemetry_log_error;
 438         }
 439 #else /* RTE_EXEC_ENV_WINDOWS */
 440         RTE_SET_USED(runtime_dir);
 441         RTE_SET_USED(cpuset);
 442         RTE_SET_USED(err_str);
 443
 444         snprintf(telemetry_log_error, sizeof(telemetry_log_error),
 445                 "DPDK Telemetry is not supported on Windows.");
 446 #endif /* RTE_EXEC_ENV_WINDOWS */
 447
 448         return 0;
 449 }