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_thread_proc.h"
63 #include "ap_config.h"
65 #include "http_main.h"
67 #include "http_config.h" /* for read_config */
68 #include "http_core.h" /* for get_remote_host */
69 #include "http_connection.h"
72 #include "iol_socket.h"
73 #include "ap_listen.h"
74 #include "scoreboard.h"
76 #ifdef HAVE_NETINET_TCP_H
77 #include <netinet/tcp.h>
84 * Actual definitions of config globals
87 int ap_threads_per_child=0; /* Worker threads per child */
88 int ap_max_requests_per_child=0;
89 static char *ap_pid_fname=NULL;
90 API_VAR_EXPORT char *ap_scoreboard_fname=NULL;
91 static int ap_daemons_to_start=0;
92 static int min_spare_threads=0;
93 static int max_spare_threads=0;
94 static int ap_daemons_limit=0;
95 static time_t ap_restart_time=0;
96 API_VAR_EXPORT int ap_extended_status = 0;
97 static int workers_may_exit = 0;
98 static int requests_this_child;
99 static int num_listensocks = 0;
100 static ap_socket_t **listensocks;
102 /* The structure used to pass unique initialization info to each thread */
107 ap_pool_t *tpool; /* "pthread" would be confusing */
111 * The max child slot ever assigned, preserved across restarts. Necessary
112 * to deal with MaxClients changes across SIGWINCH restarts. We use this
113 * value to optimize routines that have to scan the entire scoreboard.
115 int ap_max_daemons_limit = -1;
117 static char ap_coredump_dir[MAX_STRING_LEN];
119 int pipe_of_death[2];
120 static pthread_mutex_t pipe_of_death_mutex;
122 /* *Non*-shared http_main globals... */
124 server_rec *ap_server_conf;
126 /* one_process --- debugging mode variable; can be set from the command line
127 * with the -X flag. If set, this gets you the child_main loop running
128 * in the process which originally started up (no detach, no make_child),
129 * which is a pretty nice debugging environment. (You'll get a SIGHUP
130 * early in standalone_main; just continue through. This is the server
131 * trying to kill off any child processes which it might have lying
132 * around --- Apache doesn't keep track of their pids, it just sends
133 * SIGHUP to the process group, ignoring it in the root process.
134 * Continue through and you'll be fine.).
137 static int one_process = 0;
140 int raise_sigstop_flags;
143 static ap_pool_t *pconf; /* Pool for config stuff */
144 static ap_pool_t *pchild; /* Pool for httpd child stuff */
146 int ap_my_pid; /* Linux getpid() doesn't work except in main thread. Use
148 /* Keep track of the number of worker threads currently active */
149 static int worker_thread_count;
150 static pthread_mutex_t worker_thread_count_mutex;
152 /* Locks for accept serialization */
153 static pthread_mutex_t thread_accept_mutex = PTHREAD_MUTEX_INITIALIZER;
154 static ap_lock_t *process_accept_mutex;
155 static char *lock_fname;
157 #ifdef NO_SERIALIZED_ACCEPT
158 #define SAFE_ACCEPT(stmt) APR_SUCCESS
160 #define SAFE_ACCEPT(stmt) (stmt)
164 /* Global, alas, so http_core can talk to us */
165 enum server_token_type ap_server_tokens = SrvTk_FULL;
167 API_EXPORT(const server_rec *) ap_get_server_conf(void)
169 return (ap_server_conf);
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 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;
260 static void sig_term(int sig)
265 static void restart(int sig)
268 ap_start_restart(sig == SIGWINCH);
274 static void set_signals(void)
276 #ifndef NO_USE_SIGACTION
279 sigemptyset(&sa.sa_mask);
283 sa.sa_handler = sig_coredump;
284 #if defined(SA_ONESHOT)
285 sa.sa_flags = SA_ONESHOT;
286 #elif defined(SA_RESETHAND)
287 sa.sa_flags = SA_RESETHAND;
289 if (sigaction(SIGSEGV, &sa, NULL) < 0)
290 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGSEGV)");
292 if (sigaction(SIGBUS, &sa, NULL) < 0)
293 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGBUS)");
296 if (sigaction(SIGABORT, &sa, NULL) < 0)
297 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_ap_server_conf, "sigaction(SIGABORT)");
300 if (sigaction(SIGABRT, &sa, NULL) < 0)
301 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGABRT)");
304 if (sigaction(SIGILL, &sa, NULL) < 0)
305 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGILL)");
309 sa.sa_handler = sig_term;
310 if (sigaction(SIGTERM, &sa, NULL) < 0)
311 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGTERM)");
313 if (sigaction(SIGINT, &sa, NULL) < 0)
314 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGINT)");
317 sa.sa_handler = SIG_DFL;
318 if (sigaction(SIGXCPU, &sa, NULL) < 0)
319 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGXCPU)");
322 sa.sa_handler = SIG_DFL;
323 if (sigaction(SIGXFSZ, &sa, NULL) < 0)
324 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGXFSZ)");
327 sa.sa_handler = SIG_IGN;
328 if (sigaction(SIGPIPE, &sa, NULL) < 0)
329 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGPIPE)");
332 /* we want to ignore HUPs and WINCH while we're busy processing one */
333 sigaddset(&sa.sa_mask, SIGHUP);
334 sigaddset(&sa.sa_mask, SIGWINCH);
335 sa.sa_handler = restart;
336 if (sigaction(SIGHUP, &sa, NULL) < 0)
337 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGHUP)");
338 if (sigaction(SIGWINCH, &sa, NULL) < 0)
339 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGWINCH)");
342 ap_signal(SIGSEGV, sig_coredump);
344 ap_signal(SIGBUS, sig_coredump);
347 ap_signal(SIGABORT, sig_coredump);
348 #endif /* SIGABORT */
350 ap_signal(SIGABRT, sig_coredump);
353 ap_signal(SIGILL, sig_coredump);
356 ap_signal(SIGXCPU, SIG_DFL);
359 ap_signal(SIGXFSZ, SIG_DFL);
363 ap_signal(SIGTERM, sig_term);
365 ap_signal(SIGHUP, restart);
368 ap_signal(SIGWINCH, restart);
369 #endif /* SIGWINCH */
371 ap_signal(SIGPIPE, SIG_IGN);
377 static void process_child_status(ap_proc_t *abs_pid, ap_wait_t status)
380 ap_get_os_proc(&pid, abs_pid);
381 /* Child died... if it died due to a fatal error,
382 * we should simply bail out.
384 if ((WIFEXITED(status)) &&
385 WEXITSTATUS(status) == APEXIT_CHILDFATAL) {
386 ap_log_error(APLOG_MARK, APLOG_ALERT|APLOG_NOERRNO, 0, ap_server_conf,
387 "Child %d returned a Fatal error... \n"
388 "Apache is exiting!",
390 exit(APEXIT_CHILDFATAL);
392 if (WIFSIGNALED(status)) {
393 switch (WTERMSIG(status)) {
402 if (WCOREDUMP(status)) {
403 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE,
405 "child pid %d exit signal %s (%d), "
406 "possible coredump in %s",
407 pid, (WTERMSIG(status) >= NumSIG) ? "" :
408 SYS_SIGLIST[WTERMSIG(status)], WTERMSIG(status),
413 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE,
415 "child pid %d exit signal %s (%d)", pid,
416 SYS_SIGLIST[WTERMSIG(status)], WTERMSIG(status));
421 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE,
423 "child pid %d exit signal %d",
424 pid, WTERMSIG(status));
430 static int setup_listeners(server_rec *s)
433 int num_listeners = 0;
434 if (ap_listen_open(s->process, s->port)) {
437 for (lr = ap_listeners; lr; lr = lr->next) {
440 return num_listeners;
443 /*****************************************************************
444 * Here follows a long bunch of generic server bookkeeping stuff...
447 #if defined(TCP_NODELAY) && !defined(MPE) && !defined(TPF)
448 static void sock_disable_nagle(int s)
450 /* The Nagle algorithm says that we should delay sending partial
451 * packets in hopes of getting more data. We don't want to do
452 * this; we are not telnet. There are bad interactions between
453 * persistent connections and Nagle's algorithm that have very severe
454 * performance penalties. (Failing to disable Nagle is not much of a
455 * problem with simple HTTP.)
457 * In spite of these problems, failure here is not a shooting offense.
461 if (setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (char *) &just_say_no,
463 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf,
464 "setsockopt: (TCP_NODELAY)");
469 #define sock_disable_nagle(s) /* NOOP */
472 int ap_graceful_stop_signalled(void)
474 /* XXX - Does this really work? - Manoj */
478 /*****************************************************************
479 * Child process main loop.
482 static void process_socket(ap_pool_t *p, ap_socket_t *sock, int my_child_num, int my_thread_num)
485 conn_rec *current_conn;
487 long conn_id = my_child_num * HARD_THREAD_LIMIT + my_thread_num;
490 (void) ap_get_os_sock(&csd, sock);
492 sock_disable_nagle(csd);
494 iol = unix_attach_socket(sock);
496 if (errno == EBADF) {
497 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, 0, NULL,
498 "filedescriptor (%u) larger than FD_SETSIZE (%u) "
499 "found, you probably need to rebuild Apache with a "
500 "larger FD_SETSIZE", csd, FD_SETSIZE);
503 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, NULL,
504 "error attaching to socket");
506 ap_close_socket(sock);
510 (void) ap_update_child_status(my_child_num, my_thread_num,
511 SERVER_BUSY_READ, (request_rec *) NULL);
512 conn_io = ap_bcreate(p, B_RDWR);
513 ap_bpush_iol(conn_io, iol);
515 current_conn = ap_new_apr_connection(p, ap_server_conf, conn_io, sock,
518 ap_process_connection(current_conn);
519 ap_lingering_close(current_conn);
521 /* Sets workers_may_exit if we received a character on the pipe_of_death */
522 static void check_pipe_of_death(void)
524 pthread_mutex_lock(&pipe_of_death_mutex);
525 if (!workers_may_exit) {
530 ret = ap_recv(listensocks[0], &pipe_read_char, &n);
531 if (ap_canonical_error(ret) == APR_EAGAIN) {
532 /* It lost the lottery. It must continue to suffer
533 * through a life of servitude. */
536 /* It won the lottery (or something else is very
537 * wrong). Embrace death with open arms. */
538 workers_may_exit = 1;
541 pthread_mutex_unlock(&pipe_of_death_mutex);
544 static void * worker_thread(void * dummy)
546 proc_info * ti = dummy;
547 int process_slot = ti->pid;
548 int thread_slot = ti->tid;
549 ap_pool_t *tpool = ti->tpool;
550 ap_socket_t *csd = NULL;
551 ap_pool_t *ptrans; /* Pool for per-transaction stuff */
552 ap_socket_t *sd = NULL;
554 int curr_pollfd, last_pollfd = 0;
555 ap_pollfd_t *pollset;
560 ap_create_pool(&ptrans, tpool);
562 pthread_mutex_lock(&worker_thread_count_mutex);
563 worker_thread_count++;
564 pthread_mutex_unlock(&worker_thread_count_mutex);
566 ap_setup_poll(&pollset, num_listensocks+1, tpool);
567 for(n=0 ; n <= num_listensocks ; ++n)
568 ap_add_poll_socket(pollset, listensocks[n], APR_POLLIN);
570 /* TODO: Switch to a system where threads reuse the results from earlier
571 poll calls - manoj */
572 while (!workers_may_exit) {
573 workers_may_exit |= (ap_max_requests_per_child != 0) && (requests_this_child <= 0);
574 if (workers_may_exit) break;
576 (void) ap_update_child_status(process_slot, thread_slot, SERVER_READY,
577 (request_rec *) NULL);
578 pthread_mutex_lock(&thread_accept_mutex);
579 if (workers_may_exit) {
580 pthread_mutex_unlock(&thread_accept_mutex);
583 if ((rv = SAFE_ACCEPT(ap_lock(process_accept_mutex)))
585 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
586 "ap_lock failed. Attempting to shutdown "
587 "process gracefully.");
588 workers_may_exit = 1;
591 while (!workers_may_exit) {
595 ret = ap_poll(pollset, &n, -1);
596 if (ret != APR_SUCCESS) {
597 if (ret == APR_EINTR) {
601 /* poll() will only return errors in catastrophic
602 * circumstances. Let's try exiting gracefully, for now. */
603 ap_log_error(APLOG_MARK, APLOG_ERR, errno, (const server_rec *)
604 ap_get_server_conf(), "poll: (listen)");
605 workers_may_exit = 1;
608 if (workers_may_exit) break;
610 ap_get_revents(&event, listensocks[0], pollset);
611 if (event & APR_POLLIN) {
612 /* A process got a signal on the shutdown pipe. Check if we're
613 * the lucky process to die. */
614 check_pipe_of_death();
618 if (num_listensocks == 1) {
619 sd = ap_listeners->sd;
623 /* find a listener */
624 curr_pollfd = last_pollfd;
627 if (curr_pollfd > num_listensocks) {
630 /* XXX: Should we check for POLLERR? */
631 ap_get_revents(&event, listensocks[curr_pollfd], pollset);
632 if (event & APR_POLLIN) {
633 last_pollfd = curr_pollfd;
634 sd=listensocks[curr_pollfd];
637 } while (curr_pollfd != last_pollfd);
641 if (!workers_may_exit) {
642 ap_accept(&csd, sd, ptrans);
643 if ((rv = SAFE_ACCEPT(ap_unlock(process_accept_mutex)))
645 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
646 "ap_unlock failed. Attempting to shutdown "
647 "process gracefully.");
648 workers_may_exit = 1;
650 pthread_mutex_unlock(&thread_accept_mutex);
651 process_socket(ptrans, csd, process_slot, thread_slot);
652 requests_this_child--;
655 if ((rv = SAFE_ACCEPT(ap_unlock(process_accept_mutex)))
657 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
658 "ap_unlock failed. Attempting to shutdown "
659 "process gracefully.");
660 workers_may_exit = 1;
662 pthread_mutex_unlock(&thread_accept_mutex);
665 ap_clear_pool(ptrans);
668 ap_destroy_pool(tpool);
669 ap_update_child_status(process_slot, thread_slot, SERVER_DEAD,
670 (request_rec *) NULL);
671 pthread_mutex_lock(&worker_thread_count_mutex);
672 worker_thread_count--;
673 if (worker_thread_count == 0) {
674 /* All the threads have exited, now finish the shutdown process
675 * by signalling the sigwait thread */
676 kill(ap_my_pid, SIGTERM);
678 pthread_mutex_unlock(&worker_thread_count_mutex);
684 static void child_main(int child_num_arg)
689 pthread_attr_t thread_attr;
691 int my_child_num = child_num_arg;
692 proc_info *my_info = NULL;
697 ap_my_pid = getpid();
698 ap_create_pool(&pchild, pconf);
700 /*stuff to do before we switch id's, so we have permissions.*/
701 reopen_scoreboard(pchild);
703 rv = SAFE_ACCEPT(ap_child_init_lock(&process_accept_mutex, lock_fname,
705 if (rv != APR_SUCCESS) {
706 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf,
707 "Couldn't initialize cross-process lock in child");
708 clean_child_exit(APEXIT_CHILDFATAL);
711 if (unixd_setup_child()) {
712 clean_child_exit(APEXIT_CHILDFATAL);
715 ap_child_init_hook(pchild, ap_server_conf);
717 /*done with init critical section */
719 /* All threads should mask signals out, accoring to sigwait(2) man page */
720 sigfillset(&sig_mask);
722 #ifdef SIGPROCMASK_SETS_THREAD_MASK
723 if (sigprocmask(SIG_SETMASK, &sig_mask, NULL) != 0) {
724 ap_log_error(APLOG_MARK, APLOG_ALERT, errno, ap_server_conf, "sigprocmask");
727 if (pthread_sigmask(SIG_SETMASK, &sig_mask, NULL) != 0) {
728 ap_log_error(APLOG_MARK, APLOG_ALERT, errno, ap_server_conf, "pthread_sigmask");
732 requests_this_child = ap_max_requests_per_child;
734 /* Set up the pollfd array */
735 listensocks = ap_palloc(pchild,
736 sizeof(*listensocks) * (num_listensocks + 1));
737 ap_create_tcp_socket(&listensocks[0], pchild);
738 ap_put_os_sock(&listensocks[0], &pipe_of_death[0], pchild);
739 for (lr = ap_listeners, i = 1; i <= num_listensocks; lr = lr->next, ++i)
740 listensocks[i]=lr->sd;
742 /* Setup worker threads */
744 worker_thread_count = 0;
745 pthread_mutex_init(&worker_thread_count_mutex, NULL);
746 pthread_mutex_init(&pipe_of_death_mutex, NULL);
747 pthread_attr_init(&thread_attr);
748 #ifdef PTHREAD_ATTR_SETDETACHSTATE_ARG2_ADDR
752 pthread_attr_setdetachstate(&thread_attr, &on);
755 pthread_attr_setdetachstate(&thread_attr, PTHREAD_CREATE_DETACHED);
757 for (i=0; i < ap_threads_per_child; i++) {
759 my_info = (proc_info *)malloc(sizeof(proc_info));
760 if (my_info == NULL) {
761 ap_log_error(APLOG_MARK, APLOG_ALERT, errno, ap_server_conf,
762 "malloc: out of memory");
763 clean_child_exit(APEXIT_CHILDFATAL);
765 my_info->pid = my_child_num;
768 ap_create_pool(&my_info->tpool, pchild);
770 /* We are creating threads right now */
771 (void) ap_update_child_status(my_child_num, i, SERVER_STARTING,
772 (request_rec *) NULL);
774 if (pthread_create(&thread, &thread_attr, worker_thread, my_info)) {
775 ap_log_error(APLOG_MARK, APLOG_ALERT, errno, ap_server_conf,
776 "pthread_create: unable to create worker thread");
777 /* In case system resources are maxxed out, we don't want
778 Apache running away with the CPU trying to fork over and
779 over and over again if we exit. */
781 clean_child_exit(APEXIT_CHILDFATAL);
784 worker_thread(my_info);
785 /* The SIGTERM shouldn't let us reach this point, but just in case... */
786 clean_child_exit(APEXIT_OK);
789 /* We let each thread update it's own scoreboard entry. This is done
790 * because it let's us deal with tid better.
794 pthread_attr_destroy(&thread_attr);
796 /* This thread will be the one responsible for handling signals */
797 sigemptyset(&sig_mask);
798 sigaddset(&sig_mask, SIGTERM);
799 sigaddset(&sig_mask, SIGINT);
800 ap_sigwait(&sig_mask, &signal_received);
801 switch (signal_received) {
804 just_die(signal_received);
807 ap_log_error(APLOG_MARK, APLOG_ALERT, errno, ap_server_conf,
808 "received impossible signal: %d", signal_received);
813 static int make_child(server_rec *s, int slot, time_t now)
817 if (slot + 1 > ap_max_daemons_limit) {
818 ap_max_daemons_limit = slot + 1;
823 ap_scoreboard_image->parent[slot].pid = getpid();
827 /* Tag this slot as occupied so that perform_idle_server_maintenance
828 * doesn't try to steal it */
829 (void) ap_update_child_status(slot, 0, SERVER_STARTING, (request_rec *) NULL);
831 if ((pid = fork()) == -1) {
832 ap_log_error(APLOG_MARK, APLOG_ERR, errno, s, "fork: Unable to fork new process");
834 /* fork didn't succeed. Fix the scoreboard or else
835 * it will say SERVER_STARTING forever and ever
837 (void) ap_update_child_status(slot, 0, SERVER_DEAD, (request_rec *) NULL);
839 /* In case system resources are maxxed out, we don't want
840 Apache running away with the CPU trying to fork over and
841 over and over again. */
848 #ifdef AIX_BIND_PROCESSOR
849 /* By default, AIX binds to a single processor. This bit unbinds
850 children which will then bind to another CPU.
852 #include <sys/processor.h>
853 int status = bindprocessor(BINDPROCESS, (int)getpid(),
854 PROCESSOR_CLASS_ANY);
856 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, ap_server_conf,
857 "processor unbind failed %d", status);
860 RAISE_SIGSTOP(MAKE_CHILD);
862 ap_signal(SIGTERM, just_die);
868 ap_scoreboard_image->parent[slot].pid = pid;
872 /* start up a bunch of children */
873 static void startup_children(int number_to_start)
877 for (i = 0; number_to_start && i < ap_daemons_limit; ++i) {
878 if (ap_scoreboard_image->parent[i].pid != 0) {
881 if (make_child(ap_server_conf, i, 0) < 0) {
890 * idle_spawn_rate is the number of children that will be spawned on the
891 * next maintenance cycle if there aren't enough idle servers. It is
892 * doubled up to MAX_SPAWN_RATE, and reset only when a cycle goes by
893 * without the need to spawn.
895 static int idle_spawn_rate = 1;
896 #ifndef MAX_SPAWN_RATE
897 #define MAX_SPAWN_RATE (32)
899 static int hold_off_on_exponential_spawning;
901 static void perform_idle_server_maintenance(void)
904 int idle_thread_count;
908 int free_slots[MAX_SPAWN_RATE];
912 /* initialize the free_list */
915 idle_thread_count = 0;
919 ap_sync_scoreboard_image();
920 for (i = 0; i < ap_daemons_limit; ++i) {
921 /* Initialization to satisfy the compiler. It doesn't know
922 * that ap_threads_per_child is always > 0 */
923 int status = SERVER_DEAD;
924 int any_dying_threads = 0;
925 int all_dead_threads = 1;
926 int idle_thread_addition = 0;
928 if (i >= ap_max_daemons_limit && free_length == idle_spawn_rate)
930 for (j = 0; j < ap_threads_per_child; j++) {
931 ss = &ap_scoreboard_image->servers[i][j];
934 any_dying_threads = any_dying_threads || (status == SERVER_DEAD)
935 || (status == SERVER_GRACEFUL);
936 all_dead_threads = all_dead_threads && (status == SERVER_DEAD);
938 /* We consider a starting server as idle because we started it
939 * at least a cycle ago, and if it still hasn't finished starting
940 * then we're just going to swamp things worse by forking more.
941 * So we hopefully won't need to fork more if we count it.
942 * This depends on the ordering of SERVER_READY and SERVER_STARTING.
944 if (status <= SERVER_READY) {
945 ++idle_thread_addition;
948 if (all_dead_threads && free_length < idle_spawn_rate) {
949 free_slots[free_length] = i;
952 if (!all_dead_threads) {
955 if (!any_dying_threads) {
957 idle_thread_count += idle_thread_addition;
960 ap_max_daemons_limit = last_non_dead + 1;
962 if (idle_thread_count > max_spare_threads) {
963 /* Kill off one child */
964 char char_of_death = '!';
965 if (write(pipe_of_death[1], &char_of_death, 1) == -1) {
966 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "write pipe_of_death");
970 else if (idle_thread_count < min_spare_threads) {
971 /* terminate the free list */
972 if (free_length == 0) {
973 /* only report this condition once */
974 static int reported = 0;
977 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, 0, ap_server_conf,
978 "server reached MaxClients setting, consider"
979 " raising the MaxClients setting");
986 if (idle_spawn_rate >= 8) {
987 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_INFO, 0, ap_server_conf,
988 "server seems busy, (you may need "
989 "to increase StartServers, ThreadsPerChild "
990 "or Min/MaxSparetThreads), "
991 "spawning %d children, there are around %d idle "
992 "threads, and %d total children", idle_spawn_rate,
993 idle_thread_count, total_non_dead);
995 for (i = 0; i < free_length; ++i) {
996 make_child(ap_server_conf, free_slots[i], now);
998 /* the next time around we want to spawn twice as many if this
999 * wasn't good enough, but not if we've just done a graceful
1001 if (hold_off_on_exponential_spawning) {
1002 --hold_off_on_exponential_spawning;
1004 else if (idle_spawn_rate < MAX_SPAWN_RATE) {
1005 idle_spawn_rate *= 2;
1010 idle_spawn_rate = 1;
1014 static void server_main_loop(int remaining_children_to_start)
1021 while (!restart_pending && !shutdown_pending) {
1022 /* this is a memory leak, but I'll fix it later. */
1023 pid = ap_wait_or_timeout(&status, pconf);
1026 process_child_status(pid, status);
1027 /* non-fatal death... note that it's gone in the scoreboard. */
1028 child_slot = find_child_by_pid(pid);
1029 if (child_slot >= 0) {
1030 ap_mpmt_pthread_force_reset_connection_status(child_slot);
1031 for (i = 0; i < ap_threads_per_child; i++)
1032 ap_update_child_status(child_slot, i, SERVER_DEAD, (request_rec *) NULL);
1034 if (remaining_children_to_start
1035 && child_slot < ap_daemons_limit) {
1036 /* we're still doing a 1-for-1 replacement of dead
1037 * children with new children
1039 make_child(ap_server_conf, child_slot, time(NULL));
1040 --remaining_children_to_start;
1042 #ifdef APR_HAS_OTHER_CHILD
1044 else if (ap_reap_other_child(pid, status) == 0) {
1048 else if (is_graceful) {
1049 /* Great, we've probably just lost a slot in the
1050 * scoreboard. Somehow we don't know about this
1053 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, 0, ap_server_conf,
1054 "long lost child came home! (pid %d)", pid);
1056 /* Don't perform idle maintenance when a child dies,
1057 * only do it when there's a timeout. Remember only a
1058 * finite number of children can die, and it's pretty
1059 * pathological for a lot to die suddenly.
1063 else if (remaining_children_to_start) {
1064 /* we hit a 1 second timeout in which none of the previous
1065 * generation of children needed to be reaped... so assume
1066 * they're all done, and pick up the slack if any is left.
1068 startup_children(remaining_children_to_start);
1069 remaining_children_to_start = 0;
1070 /* In any event we really shouldn't do the code below because
1071 * few of the servers we just started are in the IDLE state
1072 * yet, so we'd mistakenly create an extra server.
1077 perform_idle_server_maintenance();
1081 int ap_mpm_run(ap_pool_t *_pconf, ap_pool_t *plog, server_rec *s)
1083 int remaining_children_to_start;
1088 if (pipe(pipe_of_death) == -1) {
1089 ap_log_error(APLOG_MARK, APLOG_ERR, errno,
1090 (const server_rec*) ap_server_conf,
1091 "pipe: (pipe_of_death)");
1095 if (fcntl(pipe_of_death[0], F_SETFL, O_NONBLOCK) == -1) {
1096 ap_log_error(APLOG_MARK, APLOG_ERR, errno,
1097 (const server_rec*) ap_server_conf,
1098 "fcntl: O_NONBLOCKing (pipe_of_death)");
1102 if ((num_listensocks = setup_listeners(ap_server_conf)) < 1) {
1103 /* XXX: hey, what's the right way for the mpm to indicate a fatal error? */
1104 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_ALERT, 0, s,
1105 "no listening sockets available, shutting down");
1108 ap_log_pid(pconf, ap_pid_fname);
1110 /* Initialize cross-process accept lock */
1111 lock_fname = ap_psprintf(_pconf, "%s.%lu",
1112 ap_server_root_relative(_pconf, lock_fname),
1114 rv = ap_create_lock(&process_accept_mutex, APR_MUTEX, APR_CROSS_PROCESS,
1115 lock_fname, _pconf);
1116 if (rv != APR_SUCCESS) {
1117 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s,
1118 "Couldn't create cross-process lock");
1124 reinit_scoreboard(pconf);
1128 /* Don't thrash... */
1129 if (max_spare_threads < min_spare_threads + ap_threads_per_child)
1130 max_spare_threads = min_spare_threads + ap_threads_per_child;
1132 /* If we're doing a graceful_restart then we're going to see a lot
1133 * of children exiting immediately when we get into the main loop
1134 * below (because we just sent them SIGWINCH). This happens pretty
1135 * rapidly... and for each one that exits we'll start a new one until
1136 * we reach at least daemons_min_free. But we may be permitted to
1137 * start more than that, so we'll just keep track of how many we're
1138 * supposed to start up without the 1 second penalty between each fork.
1140 remaining_children_to_start = ap_daemons_to_start;
1141 if (remaining_children_to_start > ap_daemons_limit) {
1142 remaining_children_to_start = ap_daemons_limit;
1145 startup_children(remaining_children_to_start);
1146 remaining_children_to_start = 0;
1149 /* give the system some time to recover before kicking into
1150 * exponential mode */
1151 hold_off_on_exponential_spawning = 10;
1154 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, 0, ap_server_conf,
1155 "%s configured -- resuming normal operations",
1156 ap_get_server_version());
1157 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_INFO, 0, ap_server_conf,
1158 "Server built: %s", ap_get_server_built());
1159 restart_pending = shutdown_pending = 0;
1161 server_main_loop(remaining_children_to_start);
1163 if (shutdown_pending) {
1164 /* Time to gracefully shut down:
1165 * Kill child processes, tell them to call child_exit, etc...
1167 if (unixd_killpg(getpgrp(), SIGTERM) < 0) {
1168 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "killpg SIGTERM");
1170 ap_reclaim_child_processes(1); /* Start with SIGTERM */
1172 /* cleanup pid file on normal shutdown */
1174 const char *pidfile = NULL;
1175 pidfile = ap_server_root_relative (pconf, ap_pid_fname);
1176 if ( pidfile != NULL && unlink(pidfile) == 0)
1177 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_INFO, 0,
1179 "removed PID file %s (pid=%ld)",
1180 pidfile, (long)getpid());
1183 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, 0, ap_server_conf,
1184 "caught SIGTERM, shutting down");
1189 /* we've been told to restart */
1190 ap_signal(SIGHUP, SIG_IGN);
1193 /* not worth thinking about */
1197 /* advance to the next generation */
1198 /* XXX: we really need to make sure this new generation number isn't in
1199 * use by any of the children.
1202 ap_scoreboard_image->global.running_generation = ap_my_generation;
1203 update_scoreboard_global();
1207 char char_of_death = '!';
1209 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, 0, ap_server_conf,
1210 "SIGWINCH received. Doing graceful restart");
1212 /* give the children the signal to die */
1213 for (i = 0; i < ap_daemons_limit;) {
1214 if (write(pipe_of_death[1], &char_of_death, 1) == -1) {
1215 if (errno == EINTR) continue;
1216 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "write pipe_of_death");
1221 /* This is mostly for debugging... so that we know what is still
1222 * gracefully dealing with existing request.
1225 for (i = 0; i < ap_daemons_limit; ++i) {
1226 for (j = 0; j < ap_threads_per_child; j++) {
1227 if (ap_scoreboard_image->servers[i][j].status != SERVER_DEAD) {
1228 ap_scoreboard_image->servers[i][j].status = SERVER_GRACEFUL;
1234 /* Kill 'em all. Since the child acts the same on the parents SIGTERM
1235 * and a SIGHUP, we may as well use the same signal, because some user
1236 * pthreads are stealing signals from us left and right.
1238 if (unixd_killpg(getpgrp(), SIGTERM) < 0) {
1239 ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "killpg SIGTERM");
1241 ap_reclaim_child_processes(1); /* Start with SIGTERM */
1242 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_NOTICE, 0, ap_server_conf,
1243 "SIGHUP received. Attempting to restart");
1246 ap_restart_time = time(NULL);
1251 static void mpmt_pthread_pre_config(ap_pool_t *pconf, ap_pool_t *plog, ap_pool_t *ptemp)
1253 static int restart_num = 0;
1255 one_process = !!getenv("ONE_PROCESS");
1257 /* sigh, want this only the second time around */
1258 if (restart_num++ == 1) {
1264 ap_my_pid = getpid();
1268 ap_listen_pre_config();
1269 ap_daemons_to_start = DEFAULT_START_DAEMON;
1270 min_spare_threads = DEFAULT_MIN_FREE_DAEMON * DEFAULT_THREADS_PER_CHILD;
1271 max_spare_threads = DEFAULT_MAX_FREE_DAEMON * DEFAULT_THREADS_PER_CHILD;
1272 ap_daemons_limit = HARD_SERVER_LIMIT;
1273 ap_threads_per_child = DEFAULT_THREADS_PER_CHILD;
1274 ap_pid_fname = DEFAULT_PIDLOG;
1275 ap_scoreboard_fname = DEFAULT_SCOREBOARD;
1276 lock_fname = DEFAULT_LOCKFILE;
1277 ap_max_requests_per_child = DEFAULT_MAX_REQUESTS_PER_CHILD;
1278 ap_extended_status = 0;
1280 ap_cpystrn(ap_coredump_dir, ap_server_root, sizeof(ap_coredump_dir));
1283 static void mpmt_pthread_hooks(void)
1290 static const char *set_pidfile(cmd_parms *cmd, void *dummy, char *arg)
1292 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1297 if (cmd->server->is_virtual) {
1298 return "PidFile directive not allowed in <VirtualHost>";
1304 static const char *set_scoreboard(cmd_parms *cmd, void *dummy, char *arg)
1306 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1311 ap_scoreboard_fname = arg;
1315 static const char *set_lockfile(cmd_parms *cmd, void *dummy, char *arg)
1317 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1326 static const char *set_daemons_to_start(cmd_parms *cmd, void *dummy, char *arg)
1328 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1333 ap_daemons_to_start = atoi(arg);
1337 static const char *set_min_spare_threads(cmd_parms *cmd, void *dummy, char *arg)
1339 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1344 min_spare_threads = atoi(arg);
1345 if (min_spare_threads <= 0) {
1346 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1347 "WARNING: detected MinSpareThreads set to non-positive.");
1348 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1349 "Resetting to 1 to avoid almost certain Apache failure.");
1350 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1351 "Please read the documentation.");
1352 min_spare_threads = 1;
1358 static const char *set_max_spare_threads(cmd_parms *cmd, void *dummy, char *arg)
1360 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1365 max_spare_threads = atoi(arg);
1369 static const char *set_server_limit (cmd_parms *cmd, void *dummy, char *arg)
1371 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1376 ap_daemons_limit = atoi(arg);
1377 if (ap_daemons_limit > HARD_SERVER_LIMIT) {
1378 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1379 "WARNING: MaxClients of %d exceeds compile time limit "
1380 "of %d servers,", ap_daemons_limit, HARD_SERVER_LIMIT);
1381 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1382 " lowering MaxClients to %d. To increase, please "
1383 "see the", HARD_SERVER_LIMIT);
1384 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1385 " HARD_SERVER_LIMIT define in src/include/httpd.h.");
1386 ap_daemons_limit = HARD_SERVER_LIMIT;
1388 else if (ap_daemons_limit < 1) {
1389 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL, "WARNING: Require MaxClients > 0, setting to 1\n");
1390 ap_daemons_limit = 1;
1395 static const char *set_threads_per_child (cmd_parms *cmd, void *dummy, char *arg)
1397 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1402 ap_threads_per_child = atoi(arg);
1403 if (ap_threads_per_child > HARD_THREAD_LIMIT) {
1404 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1405 "WARNING: ThreadsPerChild of %d exceeds compile time"
1406 "limit of %d threads,", ap_threads_per_child,
1408 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1409 " lowering ThreadsPerChild to %d. To increase, please"
1410 "see the", HARD_THREAD_LIMIT);
1411 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1412 " HARD_THREAD_LIMIT define in src/include/httpd.h.");
1414 else if (ap_threads_per_child < 1) {
1415 ap_log_error(APLOG_MARK, APLOG_STARTUP | APLOG_NOERRNO, 0, NULL,
1416 "WARNING: Require ThreadsPerChild > 0, setting to 1");
1417 ap_threads_per_child = 1;
1422 static const char *set_max_requests(cmd_parms *cmd, void *dummy, char *arg)
1424 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1429 ap_max_requests_per_child = atoi(arg);
1434 static const char *set_coredumpdir (cmd_parms *cmd, void *dummy, char *arg)
1438 const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
1443 fname = ap_server_root_relative(cmd->pool, arg);
1444 if ((stat(fname, &finfo) == -1) || !S_ISDIR(finfo.st_mode)) {
1445 return ap_pstrcat(cmd->pool, "CoreDumpDirectory ", fname,
1446 " does not exist or is not a directory", NULL);
1448 ap_cpystrn(ap_coredump_dir, fname, sizeof(ap_coredump_dir));
1452 static const command_rec mpmt_pthread_cmds[] = {
1453 UNIX_DAEMON_COMMANDS
1455 { "PidFile", set_pidfile, NULL, RSRC_CONF, TAKE1,
1456 "A file for logging the server process ID"},
1457 { "ScoreBoardFile", set_scoreboard, NULL, RSRC_CONF, TAKE1,
1458 "A file for Apache to maintain runtime process management information"},
1459 { "LockFile", set_lockfile, NULL, RSRC_CONF, TAKE1,
1460 "The lockfile used when Apache needs to lock the accept() call"},
1461 { "StartServers", set_daemons_to_start, NULL, RSRC_CONF, TAKE1,
1462 "Number of child processes launched at server startup" },
1463 { "MinSpareThreads", set_min_spare_threads, NULL, RSRC_CONF, TAKE1,
1464 "Minimum number of idle children, to handle request spikes" },
1465 { "MaxSpareThreads", set_max_spare_threads, NULL, RSRC_CONF, TAKE1,
1466 "Maximum number of idle children" },
1467 { "MaxClients", set_server_limit, NULL, RSRC_CONF, TAKE1,
1468 "Maximum number of children alive at the same time" },
1469 { "ThreadsPerChild", set_threads_per_child, NULL, RSRC_CONF, TAKE1,
1470 "Number of threads each child creates" },
1471 { "MaxRequestsPerChild", set_max_requests, NULL, RSRC_CONF, TAKE1,
1472 "Maximum number of requests a particular child serves before dying." },
1473 { "CoreDumpDirectory", set_coredumpdir, NULL, RSRC_CONF, TAKE1,
1474 "The location of the directory Apache changes to before dumping core" },
1478 module MODULE_VAR_EXPORT mpm_mpmt_pthread_module = {
1480 mpmt_pthread_pre_config, /* run hook before the configuration is read */
1481 NULL, /* create per-directory config structure */
1482 NULL, /* merge per-directory config structures */
1483 NULL, /* create per-server config structure */
1484 NULL, /* merge per-server config structures */
1485 mpmt_pthread_cmds, /* command ap_table_t */
1486 NULL, /* handlers */
1487 mpmt_pthread_hooks /* register_hooks */