1 /* ====================================================================
2 * The Apache Software License, Version 1.1
4 * Copyright (c) 2000 The Apache Software Foundation. All rights
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
19 * 3. The end-user documentation included with the redistribution,
20 * if any, must include the following acknowledgment:
21 * "This product includes software developed by the
22 * Apache Software Foundation (http://www.apache.org/)."
23 * Alternately, this acknowledgment may appear in the software itself,
24 * if and wherever such third-party acknowledgments normally appear.
26 * 4. The names "Apache" and "Apache Software Foundation" must
27 * not be used to endorse or promote products derived from this
28 * software without prior written permission. For written
29 * permission, please contact apache@apache.org.
31 * 5. Products derived from this software may not be called "Apache",
32 * nor may "Apache" appear in their name, without prior written
33 * permission of the Apache Software Foundation.
35 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
36 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
37 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
38 * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
39 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
40 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
41 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
42 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
43 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
44 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
45 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
47 * ====================================================================
49 * This software consists of voluntary contributions made by many
50 * individuals on behalf of the Apache Software Foundation. For more
51 * information on the Apache Software Foundation, please see
52 * <http://www.apache.org/>.
54 * Portions of this software are based upon public domain software
55 * originally written at the National Center for Supercomputing Applications,
56 * University of Illinois, Urbana-Champaign.
61 #include "apr_portable.h"
62 #include "apr_strings.h"
63 #include "apr_file_io.h"
64 #include "apr_thread_proc.h"
65 #include "ap_config.h"
67 #include "http_main.h"
69 #include "http_config.h" /* for read_config */
70 #include "http_core.h" /* for get_remote_host */
71 #include "http_connection.h"
74 #include "mpm_common.h"
76 #include "ap_listen.h"
77 #include "scoreboard.h"
79 #ifdef HAVE_NETINET_TCP_H
80 #include <netinet/tcp.h>
82 #ifdef HAVE_SYS_SOCKET_H
83 #include <sys/socket.h>
85 #ifdef HAVE_SYS_WAIT_H
92 * Actual definitions of config globals
95 int ap_threads_per_child=0; /* Worker threads per child */
96 int ap_max_requests_per_child=0;
97 static const char *ap_pid_fname=NULL;
98 API_VAR_EXPORT const char *ap_scoreboard_fname=NULL;
99 static int ap_daemons_to_start=0;
100 static int min_spare_threads=0;
101 static int max_spare_threads=0;
102 static int ap_daemons_limit=0;
103 static time_t ap_restart_time=0;
104 API_VAR_EXPORT int ap_extended_status = 0;
105 static int workers_may_exit = 0;
106 static int requests_this_child;
107 static int num_listensocks = 0;
108 static ap_socket_t **listensocks;
110 /* The structure used to pass unique initialization info to each thread */
115 ap_pool_t *tpool; /* "pthread" would be confusing */
119 * The max child slot ever assigned, preserved across restarts. Necessary
120 * to deal with MaxClients changes across SIGWINCH restarts. We use this
121 * value to optimize routines that have to scan the entire scoreboard.
123 int ap_max_daemons_limit = -1;
125 char ap_coredump_dir[MAX_STRING_LEN];
127 static ap_file_t *pipe_of_death_in = NULL;
128 static ap_file_t *pipe_of_death_out = NULL;
129 static pthread_mutex_t pipe_of_death_mutex;
131 /* *Non*-shared http_main globals... */
133 server_rec *ap_server_conf;
135 /* one_process --- debugging mode variable; can be set from the command line
136 * with the -X flag. If set, this gets you the child_main loop running
137 * in the process which originally started up (no detach, no make_child),
138 * which is a pretty nice debugging environment. (You'll get a SIGHUP
139 * early in standalone_main; just continue through. This is the server
140 * trying to kill off any child processes which it might have lying
141 * around --- Apache doesn't keep track of their pids, it just sends
142 * SIGHUP to the process group, ignoring it in the root process.
143 * Continue through and you'll be fine.).
146 static int one_process = 0;
149 int raise_sigstop_flags;
152 static ap_pool_t *pconf; /* Pool for config stuff */
153 static ap_pool_t *pchild; /* Pool for httpd child stuff */
155 unsigned int ap_my_pid; /* Linux getpid() doesn't work except in main
156 thread. Use this instead */
157 /* Keep track of the number of worker threads currently active */
158 static int worker_thread_count;
159 static pthread_mutex_t worker_thread_count_mutex;
161 /* Locks for accept serialization */
162 static pthread_mutex_t thread_accept_mutex = PTHREAD_MUTEX_INITIALIZER;
163 static ap_lock_t *process_accept_mutex;
164 static const char *lock_fname;
166 #ifdef NO_SERIALIZED_ACCEPT
167 #define SAFE_ACCEPT(stmt) APR_SUCCESS
169 #define SAFE_ACCEPT(stmt) (stmt)
172 API_EXPORT(int) ap_get_max_daemons(void)
174 return ap_max_daemons_limit;
177 /* a clean exit from a child with proper cleanup */
178 static void clean_child_exit(int code) __attribute__ ((noreturn));
179 void clean_child_exit(int code)
182 ap_destroy_pool(pchild);
187 /* handle all varieties of core dumping signals */
188 static void sig_coredump(int sig)
190 chdir(ap_coredump_dir);
191 ap_signal(sig, SIG_DFL);
192 kill(ap_my_pid, sig);
193 /* At this point we've got sig blocked, because we're still inside
194 * the signal handler. When we leave the signal handler it will
195 * be unblocked, and we'll take the signal... and coredump or whatever
196 * is appropriate for this particular Unix. In addition the parent
197 * will see the real signal we received -- whereas if we called
198 * abort() here, the parent would only see SIGABRT.
202 static void just_die(int sig)
207 /*****************************************************************
208 * Connection structures and accounting...
211 /* volatile just in case */
212 static int volatile shutdown_pending;
213 static int volatile restart_pending;
214 static int volatile is_graceful;
215 ap_generation_t volatile ap_my_generation;
218 * ap_start_shutdown() and ap_start_restart(), below, are a first stab at
219 * functions to initiate shutdown or restart without relying on signals.
220 * Previously this was initiated in sig_term() and restart() signal handlers,
221 * but we want to be able to start a shutdown/restart from other sources --
222 * e.g. on Win32, from the service manager. Now the service manager can
223 * call ap_start_shutdown() or ap_start_restart() as appropiate. Note that
224 * these functions can also be called by the child processes, since global
225 * variables are no longer used to pass on the required action to the parent.
227 * These should only be called from the parent process itself, since the
228 * parent process will use the shutdown_pending and restart_pending variables
229 * to determine whether to shutdown or restart. The child process should
230 * call signal_parent() directly to tell the parent to die -- this will
231 * cause neither of those variable to be set, which the parent will
232 * assume means something serious is wrong (which it will be, for the
233 * child to force an exit) and so do an exit anyway.
236 void ap_start_shutdown(void)
238 if (shutdown_pending == 1) {
239 /* Um, is this _probably_ not an error, if the user has
240 * tried to do a shutdown twice quickly, so we won't
241 * worry about reporting it.
245 shutdown_pending = 1;
248 /* do a graceful restart if graceful == 1 */
249 static void ap_start_restart(int graceful)
252 if (restart_pending == 1) {
253 /* Probably not an error - don't bother reporting it */
257 is_graceful = graceful;
259 ap_kill_cleanup(pconf, NULL, ap_cleanup_shared_mem);
263 static void sig_term(int sig)
268 static void restart(int sig)
271 ap_start_restart(sig == SIGWINCH);
277 static void set_signals(void)
279 #ifndef NO_USE_SIGACTION
282 sigemptyset(&sa.sa_mask);
286 sa.sa_handler = sig_coredump;
287 #if defined(SA_ONESHOT)
288 sa.sa_flags = SA_ONESHOT;
289 #elif defined(SA_RESETHAND)
290 sa.sa_flags = SA_RESETHAND;
292 if (sigaction(SIGSEGV, &sa, NULL) < 0)
293 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGSEGV)");
295 if (sigaction(SIGBUS, &sa, NULL) < 0)
296 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGBUS)");
299 if (sigaction(SIGABORT, &sa, NULL) < 0)
300 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGABORT)");
303 if (sigaction(SIGABRT, &sa, NULL) < 0)
304 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGABRT)");
307 if (sigaction(SIGILL, &sa, NULL) < 0)
308 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGILL)");
312 sa.sa_handler = sig_term;
313 if (sigaction(SIGTERM, &sa, NULL) < 0)
314 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGTERM)");
316 if (sigaction(SIGINT, &sa, NULL) < 0)
317 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGINT)");
320 sa.sa_handler = SIG_DFL;
321 if (sigaction(SIGXCPU, &sa, NULL) < 0)
322 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGXCPU)");
325 sa.sa_handler = SIG_DFL;
326 if (sigaction(SIGXFSZ, &sa, NULL) < 0)
327 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGXFSZ)");
330 sa.sa_handler = SIG_IGN;
331 if (sigaction(SIGPIPE, &sa, NULL) < 0)
332 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGPIPE)");
335 /* we want to ignore HUPs and WINCH while we're busy processing one */
336 sigaddset(&sa.sa_mask, SIGHUP);
337 sigaddset(&sa.sa_mask, SIGWINCH);
338 sa.sa_handler = restart;
339 if (sigaction(SIGHUP, &sa, NULL) < 0)
340 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGHUP)");
341 if (sigaction(SIGWINCH, &sa, NULL) < 0)
342 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGWINCH)");
345 ap_signal(SIGSEGV, sig_coredump);
347 ap_signal(SIGBUS, sig_coredump);
350 ap_signal(SIGABORT, sig_coredump);
351 #endif /* SIGABORT */
353 ap_signal(SIGABRT, sig_coredump);
356 ap_signal(SIGILL, sig_coredump);
359 ap_signal(SIGXCPU, SIG_DFL);
362 ap_signal(SIGXFSZ, SIG_DFL);
366 ap_signal(SIGTERM, sig_term);
368 ap_signal(SIGHUP, restart);
371 ap_signal(SIGWINCH, restart);
372 #endif /* SIGWINCH */
374 ap_signal(SIGPIPE, SIG_IGN);
380 /*****************************************************************
381 * Here follows a long bunch of generic server bookkeeping stuff...
384 int ap_graceful_stop_signalled(void)
386 /* XXX - Does this really work? - Manoj */
390 /*****************************************************************
391 * Child process main loop.
394 static void process_socket(ap_pool_t *p, ap_socket_t *sock, int my_child_num, int my_thread_num)
397 conn_rec *current_conn;
399 long conn_id = my_child_num * HARD_THREAD_LIMIT + my_thread_num;
402 (void) ap_get_os_sock(&csd, sock);
404 if (csd >= FD_SETSIZE) {
405 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, 0, NULL,
406 "new file descriptor %d is too large; you probably need "
407 "to rebuild Apache with a larger FD_SETSIZE "
410 ap_close_socket(sock);
414 ap_sock_disable_nagle(csd);
416 iol = ap_iol_attach_socket(p, sock);
418 (void) ap_update_child_status(my_child_num, my_thread_num,
419 SERVER_BUSY_READ, (request_rec *) NULL);
420 conn_io = ap_bcreate(p, B_RDWR);
421 ap_bpush_iol(conn_io, iol);
423 current_conn = ap_new_apr_connection(p, ap_server_conf, conn_io, sock,
426 ap_process_connection(current_conn);
427 ap_lingering_close(current_conn);
429 /* Sets workers_may_exit if we received a character on the pipe_of_death */
430 static void check_pipe_of_death(void)
432 pthread_mutex_lock(&pipe_of_death_mutex);
433 if (!workers_may_exit) {
438 ret = ap_recv(listensocks[0], &pipe_read_char, &n);
439 if (ap_canonical_error(ret) == APR_EAGAIN) {
440 /* It lost the lottery. It must continue to suffer
441 * through a life of servitude. */
444 /* It won the lottery (or something else is very
445 * wrong). Embrace death with open arms. */
446 workers_may_exit = 1;
449 pthread_mutex_unlock(&pipe_of_death_mutex);
452 static void * worker_thread(void * dummy)
454 proc_info * ti = dummy;
455 int process_slot = ti->pid;
456 int thread_slot = ti->tid;
457 ap_pool_t *tpool = ti->tpool;
458 ap_socket_t *csd = NULL;
459 ap_pool_t *ptrans; /* Pool for per-transaction stuff */
460 ap_socket_t *sd = NULL;
462 int curr_pollfd, last_pollfd = 0;
463 ap_pollfd_t *pollset;
468 ap_create_pool(&ptrans, tpool);
470 pthread_mutex_lock(&worker_thread_count_mutex);
471 worker_thread_count++;
472 pthread_mutex_unlock(&worker_thread_count_mutex);
474 ap_setup_poll(&pollset, num_listensocks+1, tpool);
475 for(n=0 ; n <= num_listensocks ; ++n)
476 ap_add_poll_socket(pollset, listensocks[n], APR_POLLIN);
478 /* TODO: Switch to a system where threads reuse the results from earlier
479 poll calls - manoj */
480 while (!workers_may_exit) {
481 workers_may_exit |= (ap_max_requests_per_child != 0) && (requests_this_child <= 0);
482 if (workers_may_exit) break;
484 (void) ap_update_child_status(process_slot, thread_slot, SERVER_READY,
485 (request_rec *) NULL);
486 pthread_mutex_lock(&thread_accept_mutex);
487 if (workers_may_exit) {
488 pthread_mutex_unlock(&thread_accept_mutex);
491 if ((rv = SAFE_ACCEPT(ap_lock(process_accept_mutex)))
493 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
494 "ap_lock failed. Attempting to shutdown "
495 "process gracefully.");
496 workers_may_exit = 1;
499 while (!workers_may_exit) {
503 ret = ap_poll(pollset, &n, -1);
504 if (ret != APR_SUCCESS) {
505 if (ap_canonical_error(ret) == APR_EINTR) {
509 /* ap_poll() will only return errors in catastrophic
510 * circumstances. Let's try exiting gracefully, for now. */
511 ap_log_error(APLOG_MARK, APLOG_ERR, ret, (const server_rec *)
512 ap_server_conf, "ap_poll: (listen)");
513 workers_may_exit = 1;
516 if (workers_may_exit) break;
518 ap_get_revents(&event, listensocks[0], pollset);
519 if (event & APR_POLLIN) {
520 /* A process got a signal on the shutdown pipe. Check if we're
521 * the lucky process to die. */
522 check_pipe_of_death();
526 if (num_listensocks == 1) {
527 sd = ap_listeners->sd;
531 /* find a listener */
532 curr_pollfd = last_pollfd;
535 if (curr_pollfd > num_listensocks) {
538 /* XXX: Should we check for POLLERR? */
539 ap_get_revents(&event, listensocks[curr_pollfd], pollset);
540 if (event & APR_POLLIN) {
541 last_pollfd = curr_pollfd;
542 sd=listensocks[curr_pollfd];
545 } while (curr_pollfd != last_pollfd);
549 if (!workers_may_exit) {
550 if ((rv = ap_accept(&csd, sd, ptrans)) != APR_SUCCESS) {
552 ap_log_error(APLOG_MARK, APLOG_ERR, rv, ap_server_conf,
555 if ((rv = SAFE_ACCEPT(ap_unlock(process_accept_mutex)))
557 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
558 "ap_unlock failed. Attempting to shutdown "
559 "process gracefully.");
560 workers_may_exit = 1;
562 pthread_mutex_unlock(&thread_accept_mutex);
564 process_socket(ptrans, csd, process_slot, thread_slot);
565 requests_this_child--;
569 if ((rv = SAFE_ACCEPT(ap_unlock(process_accept_mutex)))
571 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
572 "ap_unlock failed. Attempting to shutdown "
573 "process gracefully.");
574 workers_may_exit = 1;
576 pthread_mutex_unlock(&thread_accept_mutex);
579 ap_clear_pool(ptrans);
582 ap_destroy_pool(tpool);
583 ap_update_child_status(process_slot, thread_slot, SERVER_DEAD,
584 (request_rec *) NULL);
585 pthread_mutex_lock(&worker_thread_count_mutex);
586 worker_thread_count--;
587 if (worker_thread_count == 0) {
588 /* All the threads have exited, now finish the shutdown process
589 * by signalling the sigwait thread */
590 kill(ap_my_pid, SIGTERM);
592 pthread_mutex_unlock(&worker_thread_count_mutex);
598 static void child_main(int child_num_arg)
603 pthread_attr_t thread_attr;
605 int my_child_num = child_num_arg;
606 proc_info *my_info = NULL;
611 ap_my_pid = getpid();
612 ap_create_pool(&pchild, pconf);
614 /*stuff to do before we switch id's, so we have permissions.*/
615 reopen_scoreboard(pchild);
617 rv = SAFE_ACCEPT(ap_child_init_lock(&process_accept_mutex, lock_fname,
619 if (rv != APR_SUCCESS) {
620 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
621 "Couldn't initialize cross-process lock in child");
622 clean_child_exit(APEXIT_CHILDFATAL);
625 if (unixd_setup_child()) {
626 clean_child_exit(APEXIT_CHILDFATAL);
629 ap_child_init_hook(pchild, ap_server_conf);
631 /*done with init critical section */
633 /* All threads should mask signals out, accoring to sigwait(2) man page */
634 sigfillset(&sig_mask);
636 #ifdef SIGPROCMASK_SETS_THREAD_MASK
637 if (sigprocmask(SIG_SETMASK, &sig_mask, NULL) != 0) {
638 ap_log_error(APLOG_MARK, APLOG_ALERT, errno, ap_server_conf, "sigprocmask");
641 if ((rv = pthread_sigmask(SIG_SETMASK, &sig_mask, NULL)) != 0) {
642 #ifdef PTHREAD_SETS_ERRNO
645 ap_log_error(APLOG_MARK, APLOG_ALERT, rv, ap_server_conf, "pthread_sigmask");
649 requests_this_child = ap_max_requests_per_child;
651 /* Set up the pollfd array */
652 listensocks = ap_pcalloc(pchild,
653 sizeof(*listensocks) * (num_listensocks + 1));
654 #if APR_FILES_AS_SOCKETS
655 ap_socket_from_file(&listensocks[0], pipe_of_death_in);
657 for (lr = ap_listeners, i = 1; i <= num_listensocks; lr = lr->next, ++i)
658 listensocks[i]=lr->sd;
660 /* Setup worker threads */
662 worker_thread_count = 0;
663 pthread_mutex_init(&worker_thread_count_mutex, NULL);
664 pthread_mutex_init(&pipe_of_death_mutex, NULL);
665 pthread_attr_init(&thread_attr);
666 #ifdef PTHREAD_ATTR_SETDETACHSTATE_ARG2_ADDR
670 pthread_attr_setdetachstate(&thread_attr, &on);
673 pthread_attr_setdetachstate(&thread_attr, PTHREAD_CREATE_DETACHED);
675 for (i=0; i < ap_threads_per_child; i++) {
677 my_info = (proc_info *)malloc(sizeof(proc_info));
678 if (my_info == NULL) {
679 ap_log_error(APLOG_MARK, APLOG_ALERT, errno, ap_server_conf,
680 "malloc: out of memory");
681 clean_child_exit(APEXIT_CHILDFATAL);
683 my_info->pid = my_child_num;
686 ap_create_pool(&my_info->tpool, pchild);
688 /* We are creating threads right now */
689 (void) ap_update_child_status(my_child_num, i, SERVER_STARTING,
690 (request_rec *) NULL);
692 if ((rv = pthread_create(&thread, &thread_attr, worker_thread, my_info))) {
693 #ifdef PTHREAD_SETS_ERRNO
696 ap_log_error(APLOG_MARK, APLOG_ALERT, rv, ap_server_conf,
697 "pthread_create: unable to create worker thread");
698 /* In case system resources are maxxed out, we don't want
699 Apache running away with the CPU trying to fork over and
700 over and over again if we exit. */
702 clean_child_exit(APEXIT_CHILDFATAL);
705 worker_thread(my_info);
706 /* The SIGTERM shouldn't let us reach this point, but just in case... */
707 clean_child_exit(APEXIT_OK);
710 /* We let each thread update it's own scoreboard entry. This is done
711 * because it let's us deal with tid better.
715 pthread_attr_destroy(&thread_attr);
717 /* This thread will be the one responsible for handling signals */
718 sigemptyset(&sig_mask);
719 sigaddset(&sig_mask, SIGTERM);
720 sigaddset(&sig_mask, SIGINT);
721 ap_sigwait(&sig_mask, &signal_received);
722 switch (signal_received) {
725 just_die(signal_received);
728 ap_log_error(APLOG_MARK, APLOG_ALERT, errno, ap_server_conf,
729 "received impossible signal: %d", signal_received);
734 static int make_child(server_rec *s, int slot, time_t now)
738 if (slot + 1 > ap_max_daemons_limit) {
739 ap_max_daemons_limit = slot + 1;
744 ap_scoreboard_image->parent[slot].pid = getpid();
748 /* Tag this slot as occupied so that perform_idle_server_maintenance
749 * doesn't try to steal it */
750 (void) ap_update_child_status(slot, 0, SERVER_STARTING, (request_rec *) NULL);
752 if ((pid = fork()) == -1) {
753 ap_log_error(APLOG_MARK, APLOG_ERR, errno, s, "fork: Unable to fork new process");
755 /* fork didn't succeed. Fix the scoreboard or else
756 * it will say SERVER_STARTING forever and ever
758 (void) ap_update_child_status(slot, 0, SERVER_DEAD, (request_rec *) NULL);
760 /* In case system resources are maxxed out, we don't want
761 Apache running away with the CPU trying to fork over and
762 over and over again. */
769 #ifdef AIX_BIND_PROCESSOR
770 /* By default, AIX binds to a single processor. This bit unbinds
771 children which will then bind to another CPU.
773 #include <sys/processor.h>
774 int status = bindprocessor(BINDPROCESS, (int)getpid(),
775 PROCESSOR_CLASS_ANY);
777 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, errno, ap_server_conf,
778 "processor unbind failed %d", status);
781 RAISE_SIGSTOP(MAKE_CHILD);
783 ap_signal(SIGTERM, just_die);
789 ap_scoreboard_image->parent[slot].pid = pid;
793 /* start up a bunch of children */
794 static void startup_children(int number_to_start)
798 for (i = 0; number_to_start && i < ap_daemons_limit; ++i) {
799 if (ap_scoreboard_image->parent[i].pid != 0) {
802 if (make_child(ap_server_conf, i, 0) < 0) {
811 * idle_spawn_rate is the number of children that will be spawned on the
812 * next maintenance cycle if there aren't enough idle servers. It is
813 * doubled up to MAX_SPAWN_RATE, and reset only when a cycle goes by
814 * without the need to spawn.
816 static int idle_spawn_rate = 1;
817 #ifndef MAX_SPAWN_RATE
818 #define MAX_SPAWN_RATE (32)
820 static int hold_off_on_exponential_spawning;
822 static void perform_idle_server_maintenance(void)
825 int idle_thread_count;
829 int free_slots[MAX_SPAWN_RATE];
835 /* initialize the free_list */
838 idle_thread_count = 0;
842 ap_sync_scoreboard_image();
843 for (i = 0; i < ap_daemons_limit; ++i) {
844 /* Initialization to satisfy the compiler. It doesn't know
845 * that ap_threads_per_child is always > 0 */
846 int status = SERVER_DEAD;
847 int any_dying_threads = 0;
848 int all_dead_threads = 1;
849 int idle_thread_addition = 0;
851 if (i >= ap_max_daemons_limit && free_length == idle_spawn_rate)
853 for (j = 0; j < ap_threads_per_child; j++) {
854 ss = &ap_scoreboard_image->servers[i][j];
857 any_dying_threads = any_dying_threads || (status == SERVER_DEAD)
858 || (status == SERVER_GRACEFUL);
859 all_dead_threads = all_dead_threads && (status == SERVER_DEAD);
861 /* We consider a starting server as idle because we started it
862 * at least a cycle ago, and if it still hasn't finished starting
863 * then we're just going to swamp things worse by forking more.
864 * So we hopefully won't need to fork more if we count it.
865 * This depends on the ordering of SERVER_READY and SERVER_STARTING.
867 if (status <= SERVER_READY) {
868 ++idle_thread_addition;
871 if (all_dead_threads && free_length < idle_spawn_rate) {
872 free_slots[free_length] = i;
875 if (!all_dead_threads) {
878 if (!any_dying_threads) {
880 idle_thread_count += idle_thread_addition;
883 ap_max_daemons_limit = last_non_dead + 1;
885 if (idle_thread_count > max_spare_threads) {
886 /* Kill off one child */
887 char char_of_death = '!';
888 if ((rv = ap_write(pipe_of_death_out, &char_of_death, &one)) != APR_SUCCESS) {
889 ap_log_error(APLOG_MARK, APLOG_WARNING, rv, ap_server_conf, "write pipe_of_death");
893 else if (idle_thread_count < min_spare_threads) {
894 /* terminate the free list */
895 if (free_length == 0) {
896 /* only report this condition once */
897 static int reported = 0;
900 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, 0, ap_server_conf,
901 "server reached MaxClients setting, consider"
902 " raising the MaxClients setting");
909 if (idle_spawn_rate >= 8) {
910 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_INFO, 0, ap_server_conf,
911 "server seems busy, (you may need "
912 "to increase StartServers, ThreadsPerChild "
913 "or Min/MaxSpareThreads), "
914 "spawning %d children, there are around %d idle "
915 "threads, and %d total children", idle_spawn_rate,
916 idle_thread_count, total_non_dead);
918 for (i = 0; i < free_length; ++i) {
919 make_child(ap_server_conf, free_slots[i], now);
921 /* the next time around we want to spawn twice as many if this
922 * wasn't good enough, but not if we've just done a graceful
924 if (hold_off_on_exponential_spawning) {
925 --hold_off_on_exponential_spawning;
927 else if (idle_spawn_rate < MAX_SPAWN_RATE) {
928 idle_spawn_rate *= 2;
937 static void server_main_loop(int remaining_children_to_start)
944 while (!restart_pending && !shutdown_pending) {
945 ap_wait_or_timeout(&status, &pid, pconf);
948 ap_process_child_status(&pid, status);
949 /* non-fatal death... note that it's gone in the scoreboard. */
950 child_slot = find_child_by_pid(&pid);
951 if (child_slot >= 0) {
952 ap_mpmt_pthread_force_reset_connection_status(child_slot);
953 for (i = 0; i < ap_threads_per_child; i++)
954 ap_update_child_status(child_slot, i, SERVER_DEAD, (request_rec *) NULL);
956 if (remaining_children_to_start
957 && child_slot < ap_daemons_limit) {
958 /* we're still doing a 1-for-1 replacement of dead
959 * children with new children
961 make_child(ap_server_conf, child_slot, time(NULL));
962 --remaining_children_to_start;
964 #if APR_HAS_OTHER_CHILD
966 else if (ap_reap_other_child(&pid, status) == 0) {
970 else if (is_graceful) {
971 /* Great, we've probably just lost a slot in the
972 * scoreboard. Somehow we don't know about this child.
974 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, 0,
976 "long lost child came home! (pid %ld)",
979 /* Don't perform idle maintenance when a child dies,
980 * only do it when there's a timeout. Remember only a
981 * finite number of children can die, and it's pretty
982 * pathological for a lot to die suddenly.
986 else if (remaining_children_to_start) {
987 /* we hit a 1 second timeout in which none of the previous
988 * generation of children needed to be reaped... so assume
989 * they're all done, and pick up the slack if any is left.
991 startup_children(remaining_children_to_start);
992 remaining_children_to_start = 0;
993 /* In any event we really shouldn't do the code below because
994 * few of the servers we just started are in the IDLE state
995 * yet, so we'd mistakenly create an extra server.
1000 perform_idle_server_maintenance();
1004 int ap_mpm_run(ap_pool_t *_pconf, ap_pool_t *plog, server_rec *s)
1006 int remaining_children_to_start;
1012 rv = ap_create_pipe(&pipe_of_death_in, &pipe_of_death_out, pconf);
1013 if (rv != APR_SUCCESS) {
1014 ap_log_error(APLOG_MARK, APLOG_ERR, rv,
1015 (const server_rec*) ap_server_conf,
1016 "ap_create_pipe (pipe_of_death)");
1020 if ((rv = ap_set_pipe_timeout(pipe_of_death_in, 0)) != APR_SUCCESS) {
1021 ap_log_error(APLOG_MARK, APLOG_ERR, rv,
1022 (const server_rec*) ap_server_conf,
1023 "ap_set_pipe_timeout (pipe_of_death)");
1027 if ((num_listensocks = ap_setup_listeners(ap_server_conf)) < 1) {
1028 /* XXX: hey, what's the right way for the mpm to indicate a fatal error? */
1029 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_ALERT, 0, s,
1030 "no listening sockets available, shutting down");
1033 ap_log_pid(pconf, ap_pid_fname);
1035 /* Initialize cross-process accept lock */
1036 lock_fname = ap_psprintf(_pconf, "%s.%u",
1037 ap_server_root_relative(_pconf, lock_fname),
1039 rv = ap_create_lock(&process_accept_mutex, APR_MUTEX, APR_CROSS_PROCESS,
1040 lock_fname, _pconf);
1041 if (rv != APR_SUCCESS) {
1042 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s,
1043 "Couldn't create cross-process lock");
1049 reinit_scoreboard(pconf);
1053 /* Don't thrash... */
1054 if (max_spare_threads < min_spare_threads + ap_threads_per_child)
1055 max_spare_threads = min_spare_threads + ap_threads_per_child;
1057 /* If we're doing a graceful_restart then we're going to see a lot
1058 * of children exiting immediately when we get into the main loop
1059 * below (because we just sent them SIGWINCH). This happens pretty
1060 * rapidly... and for each one that exits we'll start a new one until
1061 * we reach at least daemons_min_free. But we may be permitted to
1062 * start more than that, so we'll just keep track of how many we're
1063 * supposed to start up without the 1 second penalty between each fork.
1065 remaining_children_to_start = ap_daemons_to_start;
1066 if (remaining_children_to_start > ap_daemons_limit) {
1067 remaining_children_to_start = ap_daemons_limit;
1070 startup_children(remaining_children_to_start);
1071 remaining_children_to_start = 0;
1074 /* give the system some time to recover before kicking into
1075 * exponential mode */
1076 hold_off_on_exponential_spawning = 10;
1079 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, 0, ap_server_conf,
1080 "%s configured -- resuming normal operations",
1081 ap_get_server_version());
1082 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_INFO, 0, ap_server_conf,
1083 "Server built: %s", ap_get_server_built());
1084 restart_pending = shutdown_pending = 0;
1086 server_main_loop(remaining_children_to_start);
1088 if (shutdown_pending) {
1089 /* Time to gracefully shut down:
1090 * Kill child processes, tell them to call child_exit, etc...
1092 if (unixd_killpg(getpgrp(), SIGTERM) < 0) {
1093 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "killpg SIGTERM");
1095 ap_reclaim_child_processes(1); /* Start with SIGTERM */
1097 /* cleanup pid file on normal shutdown */
1099 const char *pidfile = NULL;
1100 pidfile = ap_server_root_relative (pconf, ap_pid_fname);
1101 if ( pidfile != NULL && unlink(pidfile) == 0)
1102 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_INFO, 0,
1104 "removed PID file %s (pid=%ld)",
1105 pidfile, (long)getpid());
1108 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, 0, ap_server_conf,
1109 "caught SIGTERM, shutting down");
1114 /* we've been told to restart */
1115 ap_signal(SIGHUP, SIG_IGN);
1118 /* not worth thinking about */
1122 /* advance to the next generation */
1123 /* XXX: we really need to make sure this new generation number isn't in
1124 * use by any of the children.
1127 ap_scoreboard_image->global.running_generation = ap_my_generation;
1128 update_scoreboard_global();
1132 char char_of_death = '!';
1134 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, 0, ap_server_conf,
1135 "SIGWINCH received. Doing graceful restart");
1137 /* give the children the signal to die */
1138 for (i = 0; i < ap_daemons_limit;) {
1139 if ((rv = ap_write(pipe_of_death_in, &char_of_death, &one)) != APR_SUCCESS) {
1140 if (ap_canonical_error(rv) == APR_EINTR) continue;
1141 ap_log_error(APLOG_MARK, APLOG_WARNING, rv, ap_server_conf, "write pipe_of_death");
1146 /* This is mostly for debugging... so that we know what is still
1147 * gracefully dealing with existing request.
1150 for (i = 0; i < ap_daemons_limit; ++i) {
1151 for (j = 0; j < ap_threads_per_child; j++) {
1152 if (ap_scoreboard_image->servers[i][j].status != SERVER_DEAD) {
1153 ap_scoreboard_image->servers[i][j].status = SERVER_GRACEFUL;
1159 /* Kill 'em all. Since the child acts the same on the parents SIGTERM
1160 * and a SIGHUP, we may as well use the same signal, because some user
1161 * pthreads are stealing signals from us left and right.
1163 if (unixd_killpg(getpgrp(), SIGTERM) < 0) {
1164 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "killpg SIGTERM");
1166 ap_reclaim_child_processes(1); /* Start with SIGTERM */
1167 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, 0, ap_server_conf,
1168 "SIGHUP received. Attempting to restart");
1171 ap_restart_time = time(NULL);
1176 static void mpmt_pthread_pre_config(ap_pool_t *pconf, ap_pool_t *plog, ap_pool_t *ptemp)
1178 static int restart_num = 0;
1180 one_process = !!getenv("ONE_PROCESS");
1182 /* sigh, want this only the second time around */
1183 if (restart_num++ == 1) {
1189 ap_my_pid = getpid();
1193 ap_listen_pre_config();
1194 ap_daemons_to_start = DEFAULT_START_DAEMON;
1195 min_spare_threads = DEFAULT_MIN_FREE_DAEMON * DEFAULT_THREADS_PER_CHILD;
1196 max_spare_threads = DEFAULT_MAX_FREE_DAEMON * DEFAULT_THREADS_PER_CHILD;
1197 ap_daemons_limit = HARD_SERVER_LIMIT;
1198 ap_threads_per_child = DEFAULT_THREADS_PER_CHILD;
1199 ap_pid_fname = DEFAULT_PIDLOG;
1200 ap_scoreboard_fname = DEFAULT_SCOREBOARD;
1201 lock_fname = DEFAULT_LOCKFILE;
1202 ap_max_requests_per_child = DEFAULT_MAX_REQUESTS_PER_CHILD;
1203 ap_extended_status = 0;
1205 ap_cpystrn(ap_coredump_dir, ap_server_root, sizeof(ap_coredump_dir));
1208 static void mpmt_pthread_hooks(void)
1213 ap_hook_pre_config(mpmt_pthread_pre_config, NULL, NULL, AP_HOOK_MIDDLE);
1217 static const char *set_pidfile(cmd_parms *cmd, void *dummy, const char *arg)
1219 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1224 if (cmd->server->is_virtual) {
1225 return "PidFile directive not allowed in <VirtualHost>";
1231 static const char *set_scoreboard(cmd_parms *cmd, void *dummy,
1234 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1239 ap_scoreboard_fname = arg;
1243 static const char *set_lockfile(cmd_parms *cmd, void *dummy, const char *arg)
1245 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1254 static const char *set_daemons_to_start(cmd_parms *cmd, void *dummy,
1257 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1262 ap_daemons_to_start = atoi(arg);
1266 static const char *set_min_spare_threads(cmd_parms *cmd, void *dummy,
1269 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1274 min_spare_threads = atoi(arg);
1275 if (min_spare_threads <= 0) {
1276 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1277 "WARNING: detected MinSpareThreads set to non-positive.");
1278 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1279 "Resetting to 1 to avoid almost certain Apache failure.");
1280 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1281 "Please read the documentation.");
1282 min_spare_threads = 1;
1288 static const char *set_max_spare_threads(cmd_parms *cmd, void *dummy,
1291 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1296 max_spare_threads = atoi(arg);
1300 static const char *set_server_limit (cmd_parms *cmd, void *dummy,
1303 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1308 ap_daemons_limit = atoi(arg);
1309 if (ap_daemons_limit > HARD_SERVER_LIMIT) {
1310 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1311 "WARNING: MaxClients of %d exceeds compile time limit "
1312 "of %d servers,", ap_daemons_limit, HARD_SERVER_LIMIT);
1313 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1314 " lowering MaxClients to %d. To increase, please "
1315 "see the", HARD_SERVER_LIMIT);
1316 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1317 " HARD_SERVER_LIMIT define in %s.",
1318 AP_MPM_HARD_LIMITS_FILE);
1319 ap_daemons_limit = HARD_SERVER_LIMIT;
1321 else if (ap_daemons_limit < 1) {
1322 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL, "WARNING: Require MaxClients > 0, setting to 1");
1323 ap_daemons_limit = 1;
1328 static const char *set_threads_per_child (cmd_parms *cmd, void *dummy,
1331 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1336 ap_threads_per_child = atoi(arg);
1337 if (ap_threads_per_child > HARD_THREAD_LIMIT) {
1338 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1339 "WARNING: ThreadsPerChild of %d exceeds compile time"
1340 "limit of %d threads,", ap_threads_per_child,
1342 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1343 " lowering ThreadsPerChild to %d. To increase, please"
1344 " see the", HARD_THREAD_LIMIT);
1345 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1346 " HARD_THREAD_LIMIT define in %s.",
1347 AP_MPM_HARD_LIMITS_FILE);
1349 else if (ap_threads_per_child < 1) {
1350 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1351 "WARNING: Require ThreadsPerChild > 0, setting to 1");
1352 ap_threads_per_child = 1;
1357 static const char *set_max_requests(cmd_parms *cmd, void *dummy,
1360 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1365 ap_max_requests_per_child = atoi(arg);
1370 static const char *set_coredumpdir (cmd_parms *cmd, void *dummy,
1375 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1380 fname = ap_server_root_relative(cmd->pool, arg);
1381 if ((ap_stat(&finfo, fname, cmd->pool) != APR_SUCCESS) ||
1382 (finfo.filetype != APR_DIR)) {
1383 return ap_pstrcat(cmd->pool, "CoreDumpDirectory ", fname,
1384 " does not exist or is not a directory", NULL);
1386 ap_cpystrn(ap_coredump_dir, fname, sizeof(ap_coredump_dir));
1390 static const command_rec mpmt_pthread_cmds[] = {
1391 UNIX_DAEMON_COMMANDS
1393 AP_INIT_TAKE1("PidFile", set_pidfile, NULL, RSRC_CONF,
1394 "A file for logging the server process ID"),
1395 AP_INIT_TAKE1("ScoreBoardFile", set_scoreboard, NULL, RSRC_CONF,
1396 "A file for Apache to maintain runtime process management information"),
1397 AP_INIT_TAKE1("LockFile", set_lockfile, NULL, RSRC_CONF,
1398 "The lockfile used when Apache needs to lock the accept() call"),
1399 AP_INIT_TAKE1("StartServers", set_daemons_to_start, NULL, RSRC_CONF,
1400 "Number of child processes launched at server startup"),
1401 AP_INIT_TAKE1("MinSpareThreads", set_min_spare_threads, NULL, RSRC_CONF,
1402 "Minimum number of idle children, to handle request spikes"),
1403 AP_INIT_TAKE1("MaxSpareThreads", set_max_spare_threads, NULL, RSRC_CONF,
1404 "Maximum number of idle children"),
1405 AP_INIT_TAKE1("MaxClients", set_server_limit, NULL, RSRC_CONF,
1406 "Maximum number of children alive at the same time"),
1407 AP_INIT_TAKE1("ThreadsPerChild", set_threads_per_child, NULL, RSRC_CONF,
1408 "Number of threads each child creates"),
1409 AP_INIT_TAKE1("MaxRequestsPerChild", set_max_requests, NULL, RSRC_CONF,
1410 "Maximum number of requests a particular child serves before dying."),
1411 AP_INIT_TAKE1("CoreDumpDirectory", set_coredumpdir, NULL, RSRC_CONF,
1412 "The location of the directory Apache changes to before dumping core"),
1416 module MODULE_VAR_EXPORT mpm_mpmt_pthread_module = {
1418 NULL, /* hook to run before apache parses args */
1419 NULL, /* create per-directory config structure */
1420 NULL, /* merge per-directory config structures */
1421 NULL, /* create per-server config structure */
1422 NULL, /* merge per-server config structures */
1423 mpmt_pthread_cmds, /* command ap_table_t */
1424 NULL, /* handlers */
1425 mpmt_pthread_hooks /* register_hooks */