granicus.if.org Git - apache/blob - server/scoreboard.c

   1 /* Licensed to the Apache Software Foundation (ASF) under one or more
   2  * contributor license agreements.  See the NOTICE file distributed with
   3  * this work for additional information regarding copyright ownership.
   4  * The ASF licenses this file to You under the Apache License, Version 2.0
   5  * (the "License"); you may not use this file except in compliance with
   6  * the License.  You may obtain a copy of the License at
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #include "apr.h"
  18 #include "apr_strings.h"
  19 #include "apr_portable.h"
  20 #include "apr_lib.h"
  21
  22 #define APR_WANT_STRFUNC
  23 #include "apr_want.h"
  24
  25 #if APR_HAVE_SYS_TYPES_H
  26 #include <sys/types.h>
  27 #endif
  28
  29 #include "ap_config.h"
  30 #include "httpd.h"
  31 #include "http_log.h"
  32 #include "http_main.h"
  33 #include "http_core.h"
  34 #include "http_config.h"
  35 #include "ap_mpm.h"
  36
  37 #include "scoreboard.h"
  38
  39 AP_DECLARE_DATA scoreboard *ap_scoreboard_image = NULL;
  40 AP_DECLARE_DATA const char *ap_scoreboard_fname = NULL;
  41 AP_DECLARE_DATA int ap_extended_status = 0;
  42 AP_DECLARE_DATA int ap_mod_status_reqtail = 0;
  43
  44 #if APR_HAS_SHARED_MEMORY
  45
  46 #include "apr_shm.h"
  47
  48 #ifndef WIN32
  49 static /* but must be exported to mpm_winnt */
  50 #endif
  51         apr_shm_t *ap_scoreboard_shm = NULL;
  52
  53 #endif
  54
  55 APR_HOOK_STRUCT(
  56     APR_HOOK_LINK(pre_mpm)
  57 )
  58
  59 AP_IMPLEMENT_HOOK_RUN_ALL(int,pre_mpm,
  60                           (apr_pool_t *p, ap_scoreboard_e sb_type),
  61                           (p, sb_type),OK,DECLINED)
  62
  63 static APR_OPTIONAL_FN_TYPE(ap_proxy_lb_workers)
  64                                 *pfn_proxy_lb_workers;
  65 static APR_OPTIONAL_FN_TYPE(ap_proxy_lb_worker_size)
  66                                 *pfn_proxy_lb_worker_size;
  67 static APR_OPTIONAL_FN_TYPE(ap_logio_get_last_bytes)
  68                                 *pfn_ap_logio_get_last_bytes;
  69
  70 struct ap_sb_handle_t {
  71     int child_num;
  72     int thread_num;
  73 };
  74
  75 static int server_limit, thread_limit, lb_limit, lb_size;
  76 static apr_size_t scoreboard_size;
  77
  78 /*
  79  * ToDo:
  80  * This function should be renamed to cleanup_shared
  81  * and it should handle cleaning up a scoreboard shared
  82  * between processes using any form of IPC (file, shared memory
  83  * segment, etc.). Leave it as is now because it is being used
  84  * by various MPMs.
  85  */
  86 static apr_status_t ap_cleanup_shared_mem(void *d)
  87 {
  88 #if APR_HAS_SHARED_MEMORY
  89     free(ap_scoreboard_image);
  90     ap_scoreboard_image = NULL;
  91     apr_shm_destroy(ap_scoreboard_shm);
  92 #endif
  93     return APR_SUCCESS;
  94 }
  95
  96 AP_DECLARE(int) ap_calc_scoreboard_size(void)
  97 {
  98     ap_mpm_query(AP_MPMQ_HARD_LIMIT_THREADS, &thread_limit);
  99     ap_mpm_query(AP_MPMQ_HARD_LIMIT_DAEMONS, &server_limit);
 100
 101     if (!pfn_proxy_lb_workers)
 102         pfn_proxy_lb_workers = APR_RETRIEVE_OPTIONAL_FN(ap_proxy_lb_workers);
 103     if (pfn_proxy_lb_workers)
 104         lb_limit = pfn_proxy_lb_workers();
 105     else
 106         lb_limit = 0;
 107
 108     if (!pfn_proxy_lb_worker_size)
 109         pfn_proxy_lb_worker_size = APR_RETRIEVE_OPTIONAL_FN(ap_proxy_lb_worker_size);
 110     if (pfn_proxy_lb_worker_size)
 111         lb_size = pfn_proxy_lb_worker_size();
 112     else
 113         lb_size = sizeof(lb_score);
 114
 115     scoreboard_size = sizeof(global_score);
 116     scoreboard_size += sizeof(process_score) * server_limit;
 117     scoreboard_size += sizeof(worker_score) * server_limit * thread_limit;
 118     if (lb_limit && lb_size)
 119         scoreboard_size += lb_size * lb_limit;
 120
 121     pfn_ap_logio_get_last_bytes = APR_RETRIEVE_OPTIONAL_FN(ap_logio_get_last_bytes);
 122
 123     return scoreboard_size;
 124 }
 125
 126 void ap_init_scoreboard(void *shared_score)
 127 {
 128     char *more_storage;
 129     int i;
 130
 131     ap_calc_scoreboard_size();
 132     ap_scoreboard_image =
 133         calloc(1, sizeof(scoreboard) + server_limit * sizeof(worker_score *));
 134     more_storage = shared_score;
 135     ap_scoreboard_image->global = (global_score *)more_storage;
 136     more_storage += sizeof(global_score);
 137     ap_scoreboard_image->parent = (process_score *)more_storage;
 138     more_storage += sizeof(process_score) * server_limit;
 139     ap_scoreboard_image->servers =
 140         (worker_score **)((char*)ap_scoreboard_image + sizeof(scoreboard));
 141     for (i = 0; i < server_limit; i++) {
 142         ap_scoreboard_image->servers[i] = (worker_score *)more_storage;
 143         more_storage += thread_limit * sizeof(worker_score);
 144     }
 145     if (lb_limit && lb_size) {
 146         ap_scoreboard_image->balancers = (void *)more_storage;
 147         more_storage += lb_limit * lb_size;
 148     }
 149     ap_assert(more_storage == (char*)shared_score + scoreboard_size);
 150     ap_scoreboard_image->global->server_limit = server_limit;
 151     ap_scoreboard_image->global->thread_limit = thread_limit;
 152     ap_scoreboard_image->global->lb_limit     = lb_limit;
 153 }
 154
 155 /**
 156  * Create a name-based scoreboard in the given pool using the
 157  * given filename.
 158  */
 159 static apr_status_t create_namebased_scoreboard(apr_pool_t *pool,
 160                                                 const char *fname)
 161 {
 162 #if APR_HAS_SHARED_MEMORY
 163     apr_status_t rv;
 164
 165     /* The shared memory file must not exist before we create the
 166      * segment. */
 167     apr_shm_remove(fname, pool); /* ignore errors */
 168
 169     rv = apr_shm_create(&ap_scoreboard_shm, scoreboard_size, fname, pool);
 170     if (rv != APR_SUCCESS) {
 171         ap_log_error(APLOG_MARK, APLOG_CRIT, rv, NULL,
 172                      "unable to create or access scoreboard \"%s\" "
 173                      "(name-based shared memory failure)", fname);
 174         return rv;
 175     }
 176 #endif /* APR_HAS_SHARED_MEMORY */
 177     return APR_SUCCESS;
 178 }
 179
 180 /* ToDo: This function should be made to handle setting up
 181  * a scoreboard shared between processes using any IPC technique,
 182  * not just a shared memory segment
 183  */
 184 static apr_status_t open_scoreboard(apr_pool_t *pconf)
 185 {
 186 #if APR_HAS_SHARED_MEMORY
 187     apr_status_t rv;
 188     char *fname = NULL;
 189     apr_pool_t *global_pool;
 190
 191     /* We don't want to have to recreate the scoreboard after
 192      * restarts, so we'll create a global pool and never clean it.
 193      */
 194     rv = apr_pool_create(&global_pool, NULL);
 195     if (rv != APR_SUCCESS) {
 196         ap_log_error(APLOG_MARK, APLOG_CRIT, rv, NULL,
 197                      "Fatal error: unable to create global pool "
 198                      "for use by the scoreboard");
 199         return rv;
 200     }
 201
 202     /* The config says to create a name-based shmem */
 203     if (ap_scoreboard_fname) {
 204         /* make sure it's an absolute pathname */
 205         fname = ap_server_root_relative(pconf, ap_scoreboard_fname);
 206         if (!fname) {
 207             ap_log_error(APLOG_MARK, APLOG_CRIT, APR_EBADPATH, NULL,
 208                          "Fatal error: Invalid Scoreboard path %s",
 209                          ap_scoreboard_fname);
 210             return APR_EBADPATH;
 211         }
 212         return create_namebased_scoreboard(global_pool, fname);
 213     }
 214     else { /* config didn't specify, we get to choose shmem type */
 215         rv = apr_shm_create(&ap_scoreboard_shm, scoreboard_size, NULL,
 216                             global_pool); /* anonymous shared memory */
 217         if ((rv != APR_SUCCESS) && (rv != APR_ENOTIMPL)) {
 218             ap_log_error(APLOG_MARK, APLOG_CRIT, rv, NULL,
 219                          "Unable to create or access scoreboard "
 220                          "(anonymous shared memory failure)");
 221             return rv;
 222         }
 223         /* Make up a filename and do name-based shmem */
 224         else if (rv == APR_ENOTIMPL) {
 225             /* Make sure it's an absolute pathname */
 226             ap_scoreboard_fname = DEFAULT_SCOREBOARD;
 227             fname = ap_server_root_relative(pconf, ap_scoreboard_fname);
 228
 229             return create_namebased_scoreboard(global_pool, fname);
 230         }
 231     }
 232 #endif /* APR_HAS_SHARED_MEMORY */
 233     return APR_SUCCESS;
 234 }
 235
 236 /* If detach is non-zero, this is a seperate child process,
 237  * if zero, it is a forked child.
 238  */
 239 apr_status_t ap_reopen_scoreboard(apr_pool_t *p, apr_shm_t **shm, int detached)
 240 {
 241 #if APR_HAS_SHARED_MEMORY
 242     if (!detached) {
 243         return APR_SUCCESS;
 244     }
 245     if (apr_shm_size_get(ap_scoreboard_shm) < scoreboard_size) {
 246         ap_log_error(APLOG_MARK, APLOG_CRIT, 0, NULL,
 247                      "Fatal error: shared scoreboard too small for child!");
 248         apr_shm_detach(ap_scoreboard_shm);
 249         ap_scoreboard_shm = NULL;
 250         return APR_EINVAL;
 251     }
 252     /* everything will be cleared shortly */
 253     if (*shm) {
 254         *shm = ap_scoreboard_shm;
 255     }
 256 #endif
 257     return APR_SUCCESS;
 258 }
 259
 260 apr_status_t ap_cleanup_scoreboard(void *d)
 261 {
 262     if (ap_scoreboard_image == NULL) {
 263         return APR_SUCCESS;
 264     }
 265     if (ap_scoreboard_image->global->sb_type == SB_SHARED) {
 266         ap_cleanup_shared_mem(NULL);
 267     }
 268     else {
 269         free(ap_scoreboard_image->global);
 270         free(ap_scoreboard_image);
 271         ap_scoreboard_image = NULL;
 272     }
 273     return APR_SUCCESS;
 274 }
 275
 276 /* Create or reinit an existing scoreboard. The MPM can control whether
 277  * the scoreboard is shared across multiple processes or not
 278  */
 279 int ap_create_scoreboard(apr_pool_t *p, ap_scoreboard_e sb_type)
 280 {
 281     int running_gen = 0;
 282     int i;
 283 #if APR_HAS_SHARED_MEMORY
 284     apr_status_t rv;
 285 #endif
 286
 287     if (ap_scoreboard_image) {
 288         running_gen = ap_scoreboard_image->global->running_generation;
 289         ap_scoreboard_image->global->restart_time = apr_time_now();
 290         memset(ap_scoreboard_image->parent, 0,
 291                sizeof(process_score) * server_limit);
 292         for (i = 0; i < server_limit; i++) {
 293             memset(ap_scoreboard_image->servers[i], 0,
 294                    sizeof(worker_score) * thread_limit);
 295         }
 296         /* Clean up the lb workers data */
 297         if (lb_limit && lb_size) {
 298             memset(ap_scoreboard_image->balancers, 0,
 299                    lb_size * lb_limit);
 300         }
 301         return OK;
 302     }
 303
 304     ap_calc_scoreboard_size();
 305 #if APR_HAS_SHARED_MEMORY
 306     if (sb_type == SB_SHARED) {
 307         void *sb_shared;
 308         rv = open_scoreboard(p);
 309         if (rv || !(sb_shared = apr_shm_baseaddr_get(ap_scoreboard_shm))) {
 310             return HTTP_INTERNAL_SERVER_ERROR;
 311         }
 312         memset(sb_shared, 0, scoreboard_size);
 313         ap_init_scoreboard(sb_shared);
 314     }
 315     else
 316 #endif
 317     {
 318         /* A simple malloc will suffice */
 319         void *sb_mem = calloc(1, scoreboard_size);
 320         if (sb_mem == NULL) {
 321             ap_log_error(APLOG_MARK, APLOG_CRIT, 0, NULL,
 322                          "(%d)%s: cannot allocate scoreboard",
 323                          errno, strerror(errno));
 324             return HTTP_INTERNAL_SERVER_ERROR;
 325         }
 326         ap_init_scoreboard(sb_mem);
 327     }
 328
 329     ap_scoreboard_image->global->sb_type = sb_type;
 330     ap_scoreboard_image->global->running_generation = running_gen;
 331     ap_scoreboard_image->global->restart_time = apr_time_now();
 332
 333     apr_pool_cleanup_register(p, NULL, ap_cleanup_scoreboard, apr_pool_cleanup_null);
 334
 335     return OK;
 336 }
 337
 338 /* Routines called to deal with the scoreboard image
 339  * --- note that we do *not* need write locks, since update_child_status
 340  * only updates a *single* record in place, and only one process writes to
 341  * a given scoreboard slot at a time (either the child process owning that
 342  * slot, or the parent, noting that the child has died).
 343  *
 344  * As a final note --- setting the score entry to getpid() is always safe,
 345  * since when the parent is writing an entry, it's only noting SERVER_DEAD
 346  * anyway.
 347  */
 348
 349 AP_DECLARE(int) ap_exists_scoreboard_image(void)
 350 {
 351     return (ap_scoreboard_image ? 1 : 0);
 352 }
 353
 354 AP_DECLARE(void) ap_increment_counts(ap_sb_handle_t *sb, request_rec *r)
 355 {
 356     worker_score *ws;
 357     apr_off_t bytes;
 358
 359     if (!sb)
 360         return;
 361
 362     ws = &ap_scoreboard_image->servers[sb->child_num][sb->thread_num];
 363     if (pfn_ap_logio_get_last_bytes != NULL) {
 364         bytes = pfn_ap_logio_get_last_bytes(r->connection);
 365     }
 366     else if (r->method_number == M_GET && r->method[0] == 'H') {
 367         bytes = 0;
 368     }
 369     else {
 370         bytes = r->bytes_sent;
 371     }
 372
 373 #ifdef HAVE_TIMES
 374     times(&ws->times);
 375 #endif
 376     ws->access_count++;
 377     ws->my_access_count++;
 378     ws->conn_count++;
 379     ws->bytes_served += bytes;
 380     ws->my_bytes_served += bytes;
 381     ws->conn_bytes += bytes;
 382 }
 383
 384 AP_DECLARE(int) ap_find_child_by_pid(apr_proc_t *pid)
 385 {
 386     int i;
 387     int max_daemons_limit;
 388
 389     ap_mpm_query(AP_MPMQ_MAX_DAEMONS, &max_daemons_limit);
 390
 391     for (i = 0; i < max_daemons_limit; ++i) {
 392         if (ap_scoreboard_image->parent[i].pid == pid->pid) {
 393             return i;
 394         }
 395     }
 396
 397     return -1;
 398 }
 399
 400 AP_DECLARE(void) ap_create_sb_handle(ap_sb_handle_t **new_sbh, apr_pool_t *p,
 401                                      int child_num, int thread_num)
 402 {
 403     *new_sbh = (ap_sb_handle_t *)apr_palloc(p, sizeof(ap_sb_handle_t));
 404     (*new_sbh)->child_num = child_num;
 405     (*new_sbh)->thread_num = thread_num;
 406 }
 407
 408 static void copy_request(char *rbuf, apr_size_t rbuflen, request_rec *r)
 409 {
 410     char *p;
 411
 412     if (r->the_request == NULL) {
 413         apr_cpystrn(rbuf, "NULL", rbuflen);
 414         return; /* short circuit below */
 415     }
 416
 417     if (r->parsed_uri.password == NULL) {
 418         p = r->the_request;
 419     }
 420     else {
 421         /* Don't reveal the password in the server-status view */
 422         p = apr_pstrcat(r->pool, r->method, " ",
 423                         apr_uri_unparse(r->pool, &r->parsed_uri,
 424                         APR_URI_UNP_OMITPASSWORD),
 425                         r->assbackwards ? NULL : " ", r->protocol, NULL);
 426     }
 427
 428     /* now figure out if we copy over the 1st rbuflen chars or the last */
 429     if (!ap_mod_status_reqtail) {
 430         apr_cpystrn(rbuf, p, rbuflen);
 431     }
 432     else {
 433         apr_size_t slen = strlen(p);
 434         if (slen < rbuflen) {
 435             /* it all fits anyway */
 436             apr_cpystrn(rbuf, p, rbuflen);
 437         }
 438         else {
 439             apr_cpystrn(rbuf, p+(slen-rbuflen+1), rbuflen);
 440         }
 441     }
 442 }
 443
 444 static int update_child_status_internal(int child_num,
 445                                         int thread_num,
 446                                         int status,
 447                                         conn_rec *c,
 448                                         request_rec *r)
 449 {
 450     int old_status;
 451     worker_score *ws;
 452     process_score *ps;
 453     int mpm_generation;
 454
 455     ws = &ap_scoreboard_image->servers[child_num][thread_num];
 456     old_status = ws->status;
 457     ws->status = status;
 458
 459     ps = &ap_scoreboard_image->parent[child_num];
 460
 461     if (status == SERVER_READY
 462         && old_status == SERVER_STARTING) {
 463         ws->thread_num = child_num * thread_limit + thread_num;
 464         ap_mpm_query(AP_MPMQ_GENERATION, &mpm_generation);
 465         ps->generation = mpm_generation;
 466     }
 467
 468     if (ap_extended_status) {
 469         ws->last_used = apr_time_now();
 470         if (status == SERVER_READY || status == SERVER_DEAD) {
 471             /*
 472              * Reset individual counters
 473              */
 474             if (status == SERVER_DEAD) {
 475                 ws->my_access_count = 0L;
 476                 ws->my_bytes_served = 0L;
 477             }
 478             ws->conn_count = 0;
 479             ws->conn_bytes = 0;
 480         }
 481         if (r) {
 482             apr_cpystrn(ws->client, ap_get_remote_host(c, r->per_dir_config,
 483                         REMOTE_NOLOOKUP, NULL), sizeof(ws->client));
 484             copy_request(ws->request, sizeof(ws->request), r);
 485             if (r->server) {
 486                 apr_cpystrn(ws->vhost, r->server->server_hostname,
 487                             sizeof(ws->vhost));
 488             }
 489         }
 490         else if (c) {
 491             apr_cpystrn(ws->client, ap_get_remote_host(c, NULL,
 492                         REMOTE_NOLOOKUP, NULL), sizeof(ws->client));
 493             ws->request[0]='\0';
 494             ws->vhost[0]='\0';
 495         }
 496     }
 497
 498     return old_status;
 499 }
 500
 501 AP_DECLARE(int) ap_update_child_status_from_indexes(int child_num,
 502                                                     int thread_num,
 503                                                     int status,
 504                                                     request_rec *r)
 505 {
 506     if (child_num < 0) {
 507         return -1;
 508     }
 509
 510     return update_child_status_internal(child_num, thread_num, status,
 511                                         r ? r->connection : NULL,
 512                                         r);
 513 }
 514
 515 AP_DECLARE(int) ap_update_child_status(ap_sb_handle_t *sbh, int status,
 516                                       request_rec *r)
 517 {
 518     if (!sbh)
 519         return -1;
 520
 521     return update_child_status_internal(sbh->child_num, sbh->thread_num,
 522                                         status,
 523                                         r ? r->connection : NULL,
 524                                         r);
 525 }
 526
 527 AP_DECLARE(int) ap_update_child_status_from_conn(ap_sb_handle_t *sbh, int status,
 528                                        conn_rec *c)
 529 {
 530     if (!sbh)
 531         return -1;
 532
 533     return update_child_status_internal(sbh->child_num, sbh->thread_num,
 534                                         status, c, NULL);
 535 }
 536
 537 AP_DECLARE(void) ap_time_process_request(ap_sb_handle_t *sbh, int status)
 538 {
 539     worker_score *ws;
 540
 541     if (!sbh)
 542         return;
 543
 544     if (sbh->child_num < 0) {
 545         return;
 546     }
 547
 548     ws = &ap_scoreboard_image->servers[sbh->child_num][sbh->thread_num];
 549
 550     if (status == START_PREQUEST) {
 551         ws->start_time = apr_time_now();
 552     }
 553     else if (status == STOP_PREQUEST) {
 554         ws->stop_time = apr_time_now();
 555     }
 556 }
 557
 558 AP_DECLARE(worker_score *) ap_get_scoreboard_worker_from_indexes(int x, int y)
 559 {
 560     if (((x < 0) || (x >= server_limit)) ||
 561         ((y < 0) || (y >= thread_limit))) {
 562         return(NULL); /* Out of range */
 563     }
 564     return &ap_scoreboard_image->servers[x][y];
 565 }
 566
 567 AP_DECLARE(worker_score *) ap_get_scoreboard_worker(ap_sb_handle_t *sbh)
 568 {
 569     if (!sbh)
 570         return NULL;
 571
 572     return ap_get_scoreboard_worker_from_indexes(sbh->child_num,
 573                                                  sbh->thread_num);
 574 }
 575
 576 AP_DECLARE(process_score *) ap_get_scoreboard_process(int x)
 577 {
 578     if ((x < 0) || (x >= server_limit)) {
 579         return(NULL); /* Out of range */
 580     }
 581     return &ap_scoreboard_image->parent[x];
 582 }
 583
 584 AP_DECLARE(global_score *) ap_get_scoreboard_global()
 585 {
 586     return ap_scoreboard_image->global;
 587 }
 588
 589 AP_DECLARE(lb_score *) ap_get_scoreboard_lb(int lb_num)
 590 {
 591     if ( (lb_num < 0) || (lb_limit < lb_num) || (lb_size==0) ) {
 592         return(NULL); /* Out of range */
 593     }
 594     return (lb_score *) ( ((char *) ap_scoreboard_image->balancers) +
 595                           (lb_num*lb_size) );
 596 }