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