src/scheduler.c

   1 /* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2
   3 /*  Monkey HTTP Daemon
   4  *  ------------------
   5  *  Copyright (C) 2001-2010, Eduardo Silva P. <edsiper@gmail.com>
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 2 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  This program is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU Library General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with this program; if not, write to the Free Software
  19  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  20  */
  21
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <errno.h>
  25 #include <pthread.h>
  26 #include <sys/epoll.h>
  27 #include <unistd.h>
  28 #include <sys/syscall.h>
  29 #include <string.h>
  30
  31 #include "monkey.h"
  32 #include "connection.h"
  33 #include "scheduler.h"
  34 #include "memory.h"
  35 #include "epoll.h"
  36 #include "request.h"
  37 #include "cache.h"
  38 #include "config.h"
  39 #include "clock.h"
  40 #include "signals.h"
  41 #include "plugin.h"
  42 #include "utils.h"
  43
  44 /* Register thread information */
  45 int mk_sched_register_thread(pthread_t tid, int efd)
  46 {
  47     int i;
  48     struct sched_list_node *sr, *aux;
  49
  50     sr = mk_mem_malloc_z(sizeof(struct sched_list_node));
  51     sr->tid = tid;
  52     sr->pid = -1;
  53     sr->epoll_fd = efd;
  54     sr->queue = mk_mem_malloc_z(sizeof(struct sched_connection) *
  55                                 config->worker_capacity);
  56     sr->request_handler = NULL;
  57     sr->next = NULL;
  58
  59     for (i = 0; i < config->worker_capacity; i++) {
  60         /* Pre alloc IPv4 memory buffer */
  61         sr->queue[i].ipv4.data = mk_mem_malloc_z(16);
  62         sr->queue[i].status = MK_SCHEDULER_CONN_AVAILABLE;
  63     }
  64
  65     if (!sched_list) {
  66         sr->idx = 1;
  67         sched_list = sr;
  68         return 0;
  69     }
  70
  71     aux = sched_list;
  72     while (aux->next) {
  73         aux = aux->next;
  74     }
  75     sr->idx = aux->idx + 1;
  76     aux->next = sr;
  77
  78     return 0;
  79 }
  80
  81 /*
  82  * Create thread which will be listening
  83  * for incomings file descriptors
  84  */
  85 int mk_sched_launch_thread(int max_events)
  86 {
  87     int efd;
  88     pthread_t tid;
  89     pthread_attr_t attr;
  90     sched_thread_conf *thconf;
  91     pthread_mutex_t mutex_wait_register;
  92
  93     /* Creating epoll file descriptor */
  94     efd = mk_epoll_create(max_events);
  95     if (efd < 1) {
  96         return -1;
  97     }
  98
  99     /* Thread stuff */
 100     pthread_mutex_init(&mutex_wait_register, (pthread_mutexattr_t *) NULL);
 101     pthread_mutex_lock(&mutex_wait_register);
 102
 103     thconf = mk_mem_malloc(sizeof(sched_thread_conf));
 104     thconf->epoll_fd = efd;
 105     thconf->max_events = max_events;
 106
 107     pthread_attr_init(&attr);
 108     pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
 109     if (pthread_create(&tid, &attr, mk_sched_launch_epoll_loop,
 110                        (void *) thconf) != 0) {
 111         perror("pthread_create");
 112         return -1;
 113     }
 114
 115     /* Register working thread */
 116     mk_sched_register_thread(tid, efd);
 117     pthread_mutex_unlock(&mutex_wait_register);
 118
 119     return 0;
 120 }
 121
 122 /* created thread, all this calls are in the thread context */
 123 void *mk_sched_launch_epoll_loop(void *thread_conf)
 124 {
 125     sched_thread_conf *thconf;
 126     struct sched_list_node *thinfo;
 127     mk_epoll_handlers *handler;
 128
 129     /* Avoid SIGPIPE signals */
 130     mk_signal_thread_sigpipe_safe();
 131
 132     thconf = thread_conf;
 133
 134     /* Init specific thread cache */
 135     mk_cache_thread_init();
 136     mk_plugin_worker_startup();
 137
 138     /* Epoll event handlers */
 139     handler = mk_epoll_set_handlers((void *) mk_conn_read,
 140                                     (void *) mk_conn_write,
 141                                     (void *) mk_conn_error,
 142                                     (void *) mk_conn_close,
 143                                     (void *) mk_conn_timeout);
 144
 145     /* Nasty way to export task id */
 146     usleep(1000);
 147     thinfo = mk_sched_get_thread_conf();
 148     while (!thinfo) {
 149         thinfo = mk_sched_get_thread_conf();
 150     }
 151
 152     /* Glibc doesn't export to user space the gettid() syscall */
 153     thinfo->pid = syscall(__NR_gettid);
 154
 155     mk_sched_set_thread_poll(thconf->epoll_fd);
 156     mk_epoll_init(thconf->epoll_fd, handler, thconf->max_events);
 157
 158     return 0;
 159 }
 160
 161 struct request_idx *mk_sched_get_request_index()
 162 {
 163     return pthread_getspecific(request_index);
 164 }
 165
 166 void mk_sched_set_request_index(struct request_idx *ri)
 167 {
 168     pthread_setspecific(request_index, (void *) ri);
 169 }
 170
 171 void mk_sched_set_thread_poll(int epoll)
 172 {
 173     pthread_setspecific(epoll_fd, (void *) epoll);
 174 }
 175
 176 int mk_sched_get_thread_poll()
 177 {
 178     return (int) pthread_getspecific(epoll_fd);
 179 }
 180
 181 struct sched_list_node *mk_sched_get_thread_conf()
 182 {
 183     struct sched_list_node *node;
 184     pthread_t current;
 185
 186     current = pthread_self();
 187     node = sched_list;
 188     while (node) {
 189         if (pthread_equal(node->tid, current) != 0) {
 190             return node;
 191         }
 192         node = node->next;
 193     }
 194
 195     return NULL;
 196 }
 197
 198 int mk_sched_add_client(struct sched_list_node *sched, int remote_fd)
 199 {
 200     unsigned int i, ret;
 201
 202     /* Look for an available slot */
 203     for (i = 0; i < config->worker_capacity; i++) {
 204         if (sched->queue[i].status == MK_SCHEDULER_CONN_AVAILABLE) {
 205             /* Set IP */
 206             mk_socket_get_ip(remote_fd, sched->queue[i].ipv4.data);
 207             mk_pointer_set( &sched->queue[i].ipv4, sched->queue[i].ipv4.data );
 208
 209             /* Before to continue, we need to run plugin stage 20 */
 210             ret = mk_plugin_stage_run(MK_PLUGIN_STAGE_20,
 211                                       remote_fd,
 212                                       &sched->queue[i], NULL, NULL);
 213
 214             /* Close connection, otherwise continue */
 215             if (ret == MK_PLUGIN_RET_CLOSE_CONX) {
 216                 mk_conn_close(remote_fd);
 217                 return MK_PLUGIN_RET_CLOSE_CONX;
 218             }
 219
 220             /* Socket and status */
 221             sched->queue[i].socket = remote_fd;
 222             sched->queue[i].status = MK_SCHEDULER_CONN_PENDING;
 223             sched->queue[i].arrive_time = log_current_utime;
 224
 225             mk_epoll_add_client(sched->epoll_fd, remote_fd, MK_EPOLL_READ,
 226                                 MK_EPOLL_BEHAVIOR_TRIGGERED);
 227             return 0;
 228         }
 229     }
 230
 231     return -1;
 232 }
 233
 234 int mk_sched_remove_client(struct sched_list_node *sched, int remote_fd)
 235 {
 236     struct sched_connection *sc;
 237
 238     sc = mk_sched_get_connection(sched, remote_fd);
 239     if (sc) {
 240         /* Close socket and change status */
 241         close(remote_fd);
 242         sc->status = MK_SCHEDULER_CONN_AVAILABLE;
 243         return 0;
 244     }
 245     return -1;
 246 }
 247
 248 struct sched_connection *mk_sched_get_connection(struct sched_list_node
 249                                                  *sched, int remote_fd)
 250 {
 251     int i;
 252
 253     if (!sched) {
 254         sched = mk_sched_get_thread_conf();
 255         if (!sched) {
 256             close(remote_fd);
 257             return NULL;
 258         }
 259     }
 260
 261     for (i = 0; i < config->worker_capacity; i++) {
 262         if (sched->queue[i].socket == remote_fd) {
 263             return &sched->queue[i];
 264         }
 265     }
 266
 267     return NULL;
 268 }
 269
 270 int mk_sched_check_timeouts(struct sched_list_node *sched)
 271 {
 272     int i;
 273     struct request_idx *req_idx;
 274     struct client_request *req_cl;
 275
 276     /* PENDING CONN TIMEOUT */
 277     for (i = 0; i < config->worker_capacity; i++) {
 278         if (sched->queue[i].status == MK_SCHEDULER_CONN_PENDING) {
 279             if (sched->queue[i].arrive_time + config->timeout <=
 280                 log_current_utime) {
 281 #ifdef TRACE
 282                 MK_TRACE("Scheduler, closing fd %i due TIMEOUT",
 283                          sched->queue[i].socket);
 284 #endif
 285                 mk_sched_remove_client(sched, sched->queue[i].socket);
 286             }
 287         }
 288     }
 289
 290     /* PROCESSING CONN TIMEOUT */
 291     req_idx = mk_sched_get_request_index();
 292     req_cl = req_idx->first;
 293
 294     while (req_cl) {
 295         if (req_cl->status == MK_REQUEST_STATUS_INCOMPLETE) {
 296             if ((req_cl->init_time + config->timeout) >= log_current_utime) {
 297 #ifdef TRACE
 298                 MK_TRACE("Scheduler, closing fd %i due to timeout (incomplete)",
 299                          req_cl->socket);
 300 #endif
 301                 close(req_cl->socket);
 302             }
 303         }
 304         req_cl = req_cl->next;
 305     }
 306
 307     return 0;
 308 }
 309
 310 int mk_sched_update_conn_status(struct sched_list_node *sched,
 311                                 int remote_fd, int status)
 312 {
 313     int i;
 314
 315     if (!sched) {
 316         return -1;
 317     }
 318
 319     for (i = 0; i < config->workers; i++) {
 320         if (sched->queue[i].socket == remote_fd) {
 321             sched->queue[i].status = status;
 322             return 0;
 323         }
 324     }
 325     return 0;
 326 }