| /* Copyright 2001-2004 The Apache Software Foundation |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| /* The purpose of this MPM is to fix the design flaws in the threaded |
| * model. Because of the way that pthreads and mutex locks interact, |
| * it is basically impossible to cleanly gracefully shutdown a child |
| * process if multiple threads are all blocked in accept. This model |
| * fixes those problems. |
| */ |
| |
| #include "apr.h" |
| #include "apr_portable.h" |
| #include "apr_strings.h" |
| #include "apr_file_io.h" |
| #include "apr_thread_proc.h" |
| #include "apr_signal.h" |
| #include "apr_thread_mutex.h" |
| #include "apr_proc_mutex.h" |
| #include "apr_poll.h" |
| #define APR_WANT_STRFUNC |
| #include "apr_want.h" |
| |
| #if APR_HAVE_UNISTD_H |
| #include <unistd.h> |
| #endif |
| #if APR_HAVE_SYS_SOCKET_H |
| #include <sys/socket.h> |
| #endif |
| #if APR_HAVE_SYS_WAIT_H |
| #include <sys/wait.h> |
| #endif |
| #ifdef HAVE_SYS_PROCESSOR_H |
| #include <sys/processor.h> /* for bindprocessor() */ |
| #endif |
| |
| #if !APR_HAS_THREADS |
| #error The Worker MPM requires APR threads, but they are unavailable. |
| #endif |
| |
| #define CORE_PRIVATE |
| |
| #include "ap_config.h" |
| #include "httpd.h" |
| #include "http_main.h" |
| #include "http_log.h" |
| #include "http_config.h" /* for read_config */ |
| #include "http_core.h" /* for get_remote_host */ |
| #include "http_connection.h" |
| #include "ap_mpm.h" |
| #include "pod.h" |
| #include "mpm_common.h" |
| #include "ap_listen.h" |
| #include "scoreboard.h" |
| #include "fdqueue.h" |
| #include "mpm_default.h" |
| |
| #include <signal.h> |
| #include <limits.h> /* for INT_MAX */ |
| |
| /* Limit on the total --- clients will be locked out if more servers than |
| * this are needed. It is intended solely to keep the server from crashing |
| * when things get out of hand. |
| * |
| * We keep a hard maximum number of servers, for two reasons --- first off, |
| * in case something goes seriously wrong, we want to stop the fork bomb |
| * short of actually crashing the machine we're running on by filling some |
| * kernel table. Secondly, it keeps the size of the scoreboard file small |
| * enough that we can read the whole thing without worrying too much about |
| * the overhead. |
| */ |
| #ifndef DEFAULT_SERVER_LIMIT |
| #define DEFAULT_SERVER_LIMIT 16 |
| #endif |
| |
| /* Admin can't tune ServerLimit beyond MAX_SERVER_LIMIT. We want |
| * some sort of compile-time limit to help catch typos. |
| */ |
| #ifndef MAX_SERVER_LIMIT |
| #define MAX_SERVER_LIMIT 20000 |
| #endif |
| |
| /* Limit on the threads per process. Clients will be locked out if more than |
| * this * server_limit are needed. |
| * |
| * We keep this for one reason it keeps the size of the scoreboard file small |
| * enough that we can read the whole thing without worrying too much about |
| * the overhead. |
| */ |
| #ifndef DEFAULT_THREAD_LIMIT |
| #define DEFAULT_THREAD_LIMIT 64 |
| #endif |
| |
| /* Admin can't tune ThreadLimit beyond MAX_THREAD_LIMIT. We want |
| * some sort of compile-time limit to help catch typos. |
| */ |
| #ifndef MAX_THREAD_LIMIT |
| #define MAX_THREAD_LIMIT 20000 |
| #endif |
| |
| /* |
| * Actual definitions of config globals |
| */ |
| |
| int ap_threads_per_child = 0; /* Worker threads per child */ |
| static int ap_daemons_to_start = 0; |
| static int min_spare_threads = 0; |
| static int max_spare_threads = 0; |
| static int ap_daemons_limit = 0; |
| static int server_limit = DEFAULT_SERVER_LIMIT; |
| static int first_server_limit; |
| static int thread_limit = DEFAULT_THREAD_LIMIT; |
| static int first_thread_limit; |
| static int changed_limit_at_restart; |
| static int dying = 0; |
| static int workers_may_exit = 0; |
| static int start_thread_may_exit = 0; |
| static int listener_may_exit = 0; |
| static int requests_this_child; |
| static int num_listensocks = 0; |
| static int resource_shortage = 0; |
| static fd_queue_t *worker_queue; |
| static fd_queue_info_t *worker_queue_info; |
| static int mpm_state = AP_MPMQ_STARTING; |
| |
| /* The structure used to pass unique initialization info to each thread */ |
| typedef struct { |
| int pid; |
| int tid; |
| int sd; |
| } proc_info; |
| |
| /* Structure used to pass information to the thread responsible for |
| * creating the rest of the threads. |
| */ |
| typedef struct { |
| apr_thread_t **threads; |
| apr_thread_t *listener; |
| int child_num_arg; |
| apr_threadattr_t *threadattr; |
| } thread_starter; |
| |
| #define ID_FROM_CHILD_THREAD(c, t) ((c * thread_limit) + t) |
| |
| /* |
| * The max child slot ever assigned, preserved across restarts. Necessary |
| * to deal with MaxClients changes across AP_SIG_GRACEFUL restarts. We |
| * use this value to optimize routines that have to scan the entire |
| * scoreboard. |
| */ |
| int ap_max_daemons_limit = -1; |
| |
| static ap_pod_t *pod; |
| |
| /* *Non*-shared http_main globals... */ |
| |
| server_rec *ap_server_conf; |
| |
| /* The worker MPM respects a couple of runtime flags that can aid |
| * in debugging. Setting the -DNO_DETACH flag will prevent the root process |
| * from detaching from its controlling terminal. Additionally, setting |
| * the -DONE_PROCESS flag (which implies -DNO_DETACH) will get you the |
| * child_main loop running in the process which originally started up. |
| * This gives you a pretty nice debugging environment. (You'll get a SIGHUP |
| * early in standalone_main; just continue through. This is the server |
| * trying to kill off any child processes which it might have lying |
| * around --- Apache doesn't keep track of their pids, it just sends |
| * SIGHUP to the process group, ignoring it in the root process. |
| * Continue through and you'll be fine.). |
| */ |
| |
| static int one_process = 0; |
| |
| #ifdef DEBUG_SIGSTOP |
| int raise_sigstop_flags; |
| #endif |
| |
| static apr_pool_t *pconf; /* Pool for config stuff */ |
| static apr_pool_t *pchild; /* Pool for httpd child stuff */ |
| |
| static pid_t ap_my_pid; /* Linux getpid() doesn't work except in main |
| thread. Use this instead */ |
| static pid_t parent_pid; |
| static apr_os_thread_t *listener_os_thread; |
| |
| /* Locks for accept serialization */ |
| static apr_proc_mutex_t *accept_mutex; |
| |
| #ifdef SINGLE_LISTEN_UNSERIALIZED_ACCEPT |
| #define SAFE_ACCEPT(stmt) (ap_listeners->next ? (stmt) : APR_SUCCESS) |
| #else |
| #define SAFE_ACCEPT(stmt) (stmt) |
| #endif |
| |
| /* The LISTENER_SIGNAL signal will be sent from the main thread to the |
| * listener thread to wake it up for graceful termination (what a child |
| * process from an old generation does when the admin does "apachectl |
| * graceful"). This signal will be blocked in all threads of a child |
| * process except for the listener thread. |
| */ |
| #define LISTENER_SIGNAL SIGHUP |
| |
| /* An array of socket descriptors in use by each thread used to |
| * perform a non-graceful (forced) shutdown of the server. */ |
| static apr_socket_t **worker_sockets; |
| |
| static void close_worker_sockets(void) |
| { |
| int i; |
| for (i = 0; i < ap_threads_per_child; i++) { |
| if (worker_sockets[i]) { |
| apr_socket_close(worker_sockets[i]); |
| worker_sockets[i] = NULL; |
| } |
| } |
| } |
| |
| static void wakeup_listener(void) |
| { |
| listener_may_exit = 1; |
| if (!listener_os_thread) { |
| /* XXX there is an obscure path that this doesn't handle perfectly: |
| * right after listener thread is created but before |
| * listener_os_thread is set, the first worker thread hits an |
| * error and starts graceful termination |
| */ |
| return; |
| } |
| /* |
| * we should just be able to "kill(ap_my_pid, LISTENER_SIGNAL)" on all |
| * platforms and wake up the listener thread since it is the only thread |
| * with SIGHUP unblocked, but that doesn't work on Linux |
| */ |
| #ifdef HAVE_PTHREAD_KILL |
| pthread_kill(*listener_os_thread, LISTENER_SIGNAL); |
| #else |
| kill(ap_my_pid, LISTENER_SIGNAL); |
| #endif |
| } |
| |
| #define ST_INIT 0 |
| #define ST_GRACEFUL 1 |
| #define ST_UNGRACEFUL 2 |
| |
| static int terminate_mode = ST_INIT; |
| |
| static void signal_threads(int mode) |
| { |
| if (terminate_mode == mode) { |
| return; |
| } |
| terminate_mode = mode; |
| mpm_state = AP_MPMQ_STOPPING; |
| |
| /* in case we weren't called from the listener thread, wake up the |
| * listener thread |
| */ |
| wakeup_listener(); |
| |
| /* for ungraceful termination, let the workers exit now; |
| * for graceful termination, the listener thread will notify the |
| * workers to exit once it has stopped accepting new connections |
| */ |
| if (mode == ST_UNGRACEFUL) { |
| workers_may_exit = 1; |
| ap_queue_interrupt_all(worker_queue); |
| ap_queue_info_term(worker_queue_info); |
| close_worker_sockets(); /* forcefully kill all current connections */ |
| } |
| } |
| |
| AP_DECLARE(apr_status_t) ap_mpm_query(int query_code, int *result) |
| { |
| switch(query_code){ |
| case AP_MPMQ_MAX_DAEMON_USED: |
| *result = ap_max_daemons_limit; |
| return APR_SUCCESS; |
| case AP_MPMQ_IS_THREADED: |
| *result = AP_MPMQ_STATIC; |
| return APR_SUCCESS; |
| case AP_MPMQ_IS_FORKED: |
| *result = AP_MPMQ_DYNAMIC; |
| return APR_SUCCESS; |
| case AP_MPMQ_HARD_LIMIT_DAEMONS: |
| *result = server_limit; |
| return APR_SUCCESS; |
| case AP_MPMQ_HARD_LIMIT_THREADS: |
| *result = thread_limit; |
| return APR_SUCCESS; |
| case AP_MPMQ_MAX_THREADS: |
| *result = ap_threads_per_child; |
| return APR_SUCCESS; |
| case AP_MPMQ_MIN_SPARE_DAEMONS: |
| *result = 0; |
| return APR_SUCCESS; |
| case AP_MPMQ_MIN_SPARE_THREADS: |
| *result = min_spare_threads; |
| return APR_SUCCESS; |
| case AP_MPMQ_MAX_SPARE_DAEMONS: |
| *result = 0; |
| return APR_SUCCESS; |
| case AP_MPMQ_MAX_SPARE_THREADS: |
| *result = max_spare_threads; |
| return APR_SUCCESS; |
| case AP_MPMQ_MAX_REQUESTS_DAEMON: |
| *result = ap_max_requests_per_child; |
| return APR_SUCCESS; |
| case AP_MPMQ_MAX_DAEMONS: |
| *result = ap_daemons_limit; |
| return APR_SUCCESS; |
| case AP_MPMQ_MPM_STATE: |
| *result = mpm_state; |
| return APR_SUCCESS; |
| } |
| return APR_ENOTIMPL; |
| } |
| |
| /* a clean exit from a child with proper cleanup */ |
| static void clean_child_exit(int code) __attribute__ ((noreturn)); |
| static void clean_child_exit(int code) |
| { |
| mpm_state = AP_MPMQ_STOPPING; |
| if (pchild) { |
| apr_pool_destroy(pchild); |
| } |
| exit(code); |
| } |
| |
| static void just_die(int sig) |
| { |
| clean_child_exit(0); |
| } |
| |
| /***************************************************************** |
| * Connection structures and accounting... |
| */ |
| |
| /* volatile just in case */ |
| static int volatile shutdown_pending; |
| static int volatile restart_pending; |
| static int volatile is_graceful; |
| static volatile int child_fatal; |
| ap_generation_t volatile ap_my_generation; |
| |
| /* |
| * ap_start_shutdown() and ap_start_restart(), below, are a first stab at |
| * functions to initiate shutdown or restart without relying on signals. |
| * Previously this was initiated in sig_term() and restart() signal handlers, |
| * but we want to be able to start a shutdown/restart from other sources -- |
| * e.g. on Win32, from the service manager. Now the service manager can |
| * call ap_start_shutdown() or ap_start_restart() as appropiate. Note that |
| * these functions can also be called by the child processes, since global |
| * variables are no longer used to pass on the required action to the parent. |
| * |
| * These should only be called from the parent process itself, since the |
| * parent process will use the shutdown_pending and restart_pending variables |
| * to determine whether to shutdown or restart. The child process should |
| * call signal_parent() directly to tell the parent to die -- this will |
| * cause neither of those variable to be set, which the parent will |
| * assume means something serious is wrong (which it will be, for the |
| * child to force an exit) and so do an exit anyway. |
| */ |
| |
| static void ap_start_shutdown(void) |
| { |
| mpm_state = AP_MPMQ_STOPPING; |
| if (shutdown_pending == 1) { |
| /* Um, is this _probably_ not an error, if the user has |
| * tried to do a shutdown twice quickly, so we won't |
| * worry about reporting it. |
| */ |
| return; |
| } |
| shutdown_pending = 1; |
| } |
| |
| /* do a graceful restart if graceful == 1 */ |
| static void ap_start_restart(int graceful) |
| { |
| mpm_state = AP_MPMQ_STOPPING; |
| if (restart_pending == 1) { |
| /* Probably not an error - don't bother reporting it */ |
| return; |
| } |
| restart_pending = 1; |
| is_graceful = graceful; |
| } |
| |
| static void sig_term(int sig) |
| { |
| ap_start_shutdown(); |
| } |
| |
| static void restart(int sig) |
| { |
| ap_start_restart(sig == AP_SIG_GRACEFUL); |
| } |
| |
| static void set_signals(void) |
| { |
| #ifndef NO_USE_SIGACTION |
| struct sigaction sa; |
| #endif |
| |
| if (!one_process) { |
| ap_fatal_signal_setup(ap_server_conf, pconf); |
| } |
| |
| #ifndef NO_USE_SIGACTION |
| sigemptyset(&sa.sa_mask); |
| sa.sa_flags = 0; |
| |
| sa.sa_handler = sig_term; |
| if (sigaction(SIGTERM, &sa, NULL) < 0) |
| ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, |
| "sigaction(SIGTERM)"); |
| #ifdef SIGINT |
| if (sigaction(SIGINT, &sa, NULL) < 0) |
| ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, |
| "sigaction(SIGINT)"); |
| #endif |
| #ifdef SIGXCPU |
| sa.sa_handler = SIG_DFL; |
| if (sigaction(SIGXCPU, &sa, NULL) < 0) |
| ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, |
| "sigaction(SIGXCPU)"); |
| #endif |
| #ifdef SIGXFSZ |
| sa.sa_handler = SIG_DFL; |
| if (sigaction(SIGXFSZ, &sa, NULL) < 0) |
| ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, |
| "sigaction(SIGXFSZ)"); |
| #endif |
| #ifdef SIGPIPE |
| sa.sa_handler = SIG_IGN; |
| if (sigaction(SIGPIPE, &sa, NULL) < 0) |
| ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, |
| "sigaction(SIGPIPE)"); |
| #endif |
| |
| /* we want to ignore HUPs and AP_SIG_GRACEFUL while we're busy |
| * processing one */ |
| sigaddset(&sa.sa_mask, SIGHUP); |
| sigaddset(&sa.sa_mask, AP_SIG_GRACEFUL); |
| sa.sa_handler = restart; |
| if (sigaction(SIGHUP, &sa, NULL) < 0) |
| ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, |
| "sigaction(SIGHUP)"); |
| if (sigaction(AP_SIG_GRACEFUL, &sa, NULL) < 0) |
| ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, |
| "sigaction(" AP_SIG_GRACEFUL_STRING ")"); |
| #else |
| if (!one_process) { |
| #ifdef SIGXCPU |
| apr_signal(SIGXCPU, SIG_DFL); |
| #endif /* SIGXCPU */ |
| #ifdef SIGXFSZ |
| apr_signal(SIGXFSZ, SIG_DFL); |
| #endif /* SIGXFSZ */ |
| } |
| |
| apr_signal(SIGTERM, sig_term); |
| #ifdef SIGHUP |
| apr_signal(SIGHUP, restart); |
| #endif /* SIGHUP */ |
| #ifdef AP_SIG_GRACEFUL |
| apr_signal(AP_SIG_GRACEFUL, restart); |
| #endif /* AP_SIG_GRACEFUL */ |
| #ifdef SIGPIPE |
| apr_signal(SIGPIPE, SIG_IGN); |
| #endif /* SIGPIPE */ |
| |
| #endif |
| } |
| |
| /***************************************************************** |
| * Here follows a long bunch of generic server bookkeeping stuff... |
| */ |
| |
| int ap_graceful_stop_signalled(void) |
| /* XXX this is really a bad confusing obsolete name |
| * maybe it should be ap_mpm_process_exiting? |
| */ |
| { |
| /* note: for a graceful termination, listener_may_exit will be set before |
| * workers_may_exit, so check listener_may_exit |
| */ |
| return listener_may_exit; |
| } |
| |
| /***************************************************************** |
| * Child process main loop. |
| */ |
| |
| static void process_socket(apr_pool_t *p, apr_socket_t *sock, int my_child_num, |
| int my_thread_num, apr_bucket_alloc_t *bucket_alloc) |
| { |
| conn_rec *current_conn; |
| long conn_id = ID_FROM_CHILD_THREAD(my_child_num, my_thread_num); |
| int csd; |
| ap_sb_handle_t *sbh; |
| |
| ap_create_sb_handle(&sbh, p, my_child_num, my_thread_num); |
| apr_os_sock_get(&csd, sock); |
| |
| current_conn = ap_run_create_connection(p, ap_server_conf, sock, |
| conn_id, sbh, bucket_alloc); |
| if (current_conn) { |
| ap_process_connection(current_conn, sock); |
| ap_lingering_close(current_conn); |
| } |
| } |
| |
| /* requests_this_child has gone to zero or below. See if the admin coded |
| "MaxRequestsPerChild 0", and keep going in that case. Doing it this way |
| simplifies the hot path in worker_thread */ |
| static void check_infinite_requests(void) |
| { |
| if (ap_max_requests_per_child) { |
| signal_threads(ST_GRACEFUL); |
| } |
| else { |
| /* wow! if you're executing this code, you may have set a record. |
| * either this child process has served over 2 billion requests, or |
| * you're running a threaded 2.0 on a 16 bit machine. |
| * |
| * I'll buy pizza and beers at Apachecon for the first person to do |
| * the former without cheating (dorking with INT_MAX, or running with |
| * uncommitted performance patches, for example). |
| * |
| * for the latter case, you probably deserve a beer too. Greg Ames |
| */ |
| |
| requests_this_child = INT_MAX; /* keep going */ |
| } |
| } |
| |
| static void unblock_signal(int sig) |
| { |
| sigset_t sig_mask; |
| |
| sigemptyset(&sig_mask); |
| sigaddset(&sig_mask, sig); |
| #if defined(SIGPROCMASK_SETS_THREAD_MASK) |
| sigprocmask(SIG_UNBLOCK, &sig_mask, NULL); |
| #else |
| pthread_sigmask(SIG_UNBLOCK, &sig_mask, NULL); |
| #endif |
| } |
| |
| static void dummy_signal_handler(int sig) |
| { |
| /* XXX If specifying SIG_IGN is guaranteed to unblock a syscall, |
| * then we don't need this goofy function. |
| */ |
| } |
| |
| static void *listener_thread(apr_thread_t *thd, void * dummy) |
| { |
| proc_info * ti = dummy; |
| int process_slot = ti->pid; |
| apr_pool_t *tpool = apr_thread_pool_get(thd); |
| void *csd = NULL; |
| apr_pool_t *ptrans; /* Pool for per-transaction stuff */ |
| apr_pool_t *recycled_pool = NULL; |
| apr_pollset_t *pollset; |
| apr_status_t rv; |
| ap_listen_rec *lr; |
| int have_idle_worker = 0; |
| int last_poll_idx = 0; |
| |
| free(ti); |
| |
| /* ### check the status */ |
| (void) apr_pollset_create(&pollset, num_listensocks, tpool, 0); |
| |
| for (lr = ap_listeners; lr != NULL; lr = lr->next) { |
| apr_pollfd_t pfd = { 0 }; |
| |
| pfd.desc_type = APR_POLL_SOCKET; |
| pfd.desc.s = lr->sd; |
| pfd.reqevents = APR_POLLIN; |
| pfd.client_data = lr; |
| |
| /* ### check the status */ |
| (void) apr_pollset_add(pollset, &pfd); |
| } |
| |
| /* Unblock the signal used to wake this thread up, and set a handler for |
| * it. |
| */ |
| unblock_signal(LISTENER_SIGNAL); |
| apr_signal(LISTENER_SIGNAL, dummy_signal_handler); |
| |
| /* TODO: Switch to a system where threads reuse the results from earlier |
| poll calls - manoj */ |
| while (1) { |
| /* TODO: requests_this_child should be synchronized - aaron */ |
| if (requests_this_child <= 0) { |
| check_infinite_requests(); |
| } |
| if (listener_may_exit) break; |
| |
| if (!have_idle_worker) { |
| rv = ap_queue_info_wait_for_idler(worker_queue_info, |
| &recycled_pool); |
| if (APR_STATUS_IS_EOF(rv)) { |
| break; /* we've been signaled to die now */ |
| } |
| else if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf, |
| "apr_queue_info_wait failed. Attempting to " |
| " shutdown process gracefully."); |
| signal_threads(ST_GRACEFUL); |
| break; |
| } |
| have_idle_worker = 1; |
| } |
| |
| /* We've already decremented the idle worker count inside |
| * ap_queue_info_wait_for_idler. */ |
| |
| if ((rv = SAFE_ACCEPT(apr_proc_mutex_lock(accept_mutex))) |
| != APR_SUCCESS) { |
| int level = APLOG_EMERG; |
| |
| if (listener_may_exit) { |
| break; |
| } |
| if (ap_scoreboard_image->parent[process_slot].generation != |
| ap_scoreboard_image->global->running_generation) { |
| level = APLOG_DEBUG; /* common to get these at restart time */ |
| } |
| ap_log_error(APLOG_MARK, level, rv, ap_server_conf, |
| "apr_proc_mutex_lock failed. Attempting to shutdown " |
| "process gracefully."); |
| signal_threads(ST_GRACEFUL); |
| break; /* skip the lock release */ |
| } |
| |
| if (!ap_listeners->next) { |
| /* Only one listener, so skip the poll */ |
| lr = ap_listeners; |
| } |
| else { |
| while (!listener_may_exit) { |
| apr_int32_t numdesc; |
| const apr_pollfd_t *pdesc; |
| |
| rv = apr_pollset_poll(pollset, -1, &numdesc, &pdesc); |
| if (rv != APR_SUCCESS) { |
| if (APR_STATUS_IS_EINTR(rv)) { |
| continue; |
| } |
| |
| /* apr_pollset_poll() will only return errors in catastrophic |
| * circumstances. Let's try exiting gracefully, for now. */ |
| ap_log_error(APLOG_MARK, APLOG_ERR, rv, |
| (const server_rec *) ap_server_conf, |
| "apr_pollset_poll: (listen)"); |
| signal_threads(ST_GRACEFUL); |
| } |
| |
| if (listener_may_exit) break; |
| |
| /* We can always use pdesc[0], but sockets at position N |
| * could end up completely starved of attention in a very |
| * busy server. Therefore, we round-robin across the |
| * returned set of descriptors. While it is possible that |
| * the returned set of descriptors might flip around and |
| * continue to starve some sockets, we happen to know the |
| * internal pollset implementation retains ordering |
| * stability of the sockets. Thus, the round-robin should |
| * ensure that a socket will eventually be serviced. |
| */ |
| if (last_poll_idx >= numdesc) |
| last_poll_idx = 0; |
| |
| /* Grab a listener record from the client_data of the poll |
| * descriptor, and advance our saved index to round-robin |
| * the next fetch. |
| * |
| * ### hmm... this descriptor might have POLLERR rather |
| * ### than POLLIN |
| */ |
| lr = pdesc[last_poll_idx++].client_data; |
| break; |
| |
| } /* while */ |
| |
| } /* if/else */ |
| |
| if (!listener_may_exit) { |
| /* create a new transaction pool for each accepted socket */ |
| if (recycled_pool == NULL) { |
| apr_allocator_t *allocator; |
| |
| apr_allocator_create(&allocator); |
| apr_allocator_max_free_set(allocator, ap_max_mem_free); |
| apr_pool_create_ex(&ptrans, NULL, NULL, allocator); |
| apr_allocator_owner_set(allocator, ptrans); |
| } |
| else { |
| ptrans = recycled_pool; |
| } |
| apr_pool_tag(ptrans, "transaction"); |
| rv = lr->accept_func(&csd, lr, ptrans); |
| /* later we trash rv and rely on csd to indicate success/failure */ |
| AP_DEBUG_ASSERT(rv == APR_SUCCESS || !csd); |
| |
| if (rv == APR_EGENERAL) { |
| /* E[NM]FILE, ENOMEM, etc */ |
| resource_shortage = 1; |
| signal_threads(ST_GRACEFUL); |
| } |
| if ((rv = SAFE_ACCEPT(apr_proc_mutex_unlock(accept_mutex))) |
| != APR_SUCCESS) { |
| int level = APLOG_EMERG; |
| |
| if (listener_may_exit) { |
| break; |
| } |
| if (ap_scoreboard_image->parent[process_slot].generation != |
| ap_scoreboard_image->global->running_generation) { |
| level = APLOG_DEBUG; /* common to get these at restart time */ |
| } |
| ap_log_error(APLOG_MARK, level, rv, ap_server_conf, |
| "apr_proc_mutex_unlock failed. Attempting to " |
| "shutdown process gracefully."); |
| signal_threads(ST_GRACEFUL); |
| } |
| if (csd != NULL) { |
| rv = ap_queue_push(worker_queue, csd, ptrans); |
| if (rv) { |
| /* trash the connection; we couldn't queue the connected |
| * socket to a worker |
| */ |
| apr_socket_close(csd); |
| ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ap_server_conf, |
| "ap_queue_push failed"); |
| } |
| else { |
| have_idle_worker = 0; |
| } |
| } |
| } |
| else { |
| if ((rv = SAFE_ACCEPT(apr_proc_mutex_unlock(accept_mutex))) |
| != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf, |
| "apr_proc_mutex_unlock failed. Attempting to " |
| "shutdown process gracefully."); |
| signal_threads(ST_GRACEFUL); |
| } |
| break; |
| } |
| } |
| |
| ap_queue_term(worker_queue); |
| dying = 1; |
| ap_scoreboard_image->parent[process_slot].quiescing = 1; |
| |
| /* wake up the main thread */ |
| kill(ap_my_pid, SIGTERM); |
| |
| apr_thread_exit(thd, APR_SUCCESS); |
| return NULL; |
| } |
| |
| /* XXX For ungraceful termination/restart, we definitely don't want to |
| * wait for active connections to finish but we may want to wait |
| * for idle workers to get out of the queue code and release mutexes, |
| * since those mutexes are cleaned up pretty soon and some systems |
| * may not react favorably (i.e., segfault) if operations are attempted |
| * on cleaned-up mutexes. |
| */ |
| static void * APR_THREAD_FUNC worker_thread(apr_thread_t *thd, void * dummy) |
| { |
| proc_info * ti = dummy; |
| int process_slot = ti->pid; |
| int thread_slot = ti->tid; |
| apr_socket_t *csd = NULL; |
| apr_bucket_alloc_t *bucket_alloc; |
| apr_pool_t *last_ptrans = NULL; |
| apr_pool_t *ptrans; /* Pool for per-transaction stuff */ |
| apr_status_t rv; |
| int is_idle = 0; |
| |
| free(ti); |
| |
| ap_update_child_status_from_indexes(process_slot, thread_slot, SERVER_STARTING, NULL); |
| |
| while (!workers_may_exit) { |
| if (!is_idle) { |
| rv = ap_queue_info_set_idle(worker_queue_info, last_ptrans); |
| last_ptrans = NULL; |
| if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf, |
| "ap_queue_info_set_idle failed. Attempting to " |
| "shutdown process gracefully."); |
| signal_threads(ST_GRACEFUL); |
| break; |
| } |
| is_idle = 1; |
| } |
| |
| ap_update_child_status_from_indexes(process_slot, thread_slot, SERVER_READY, NULL); |
| worker_pop: |
| if (workers_may_exit) { |
| break; |
| } |
| rv = ap_queue_pop(worker_queue, &csd, &ptrans); |
| |
| if (rv != APR_SUCCESS) { |
| /* We get APR_EOF during a graceful shutdown once all the connections |
| * accepted by this server process have been handled. |
| */ |
| if (APR_STATUS_IS_EOF(rv)) { |
| break; |
| } |
| /* We get APR_EINTR whenever ap_queue_pop() has been interrupted |
| * from an explicit call to ap_queue_interrupt_all(). This allows |
| * us to unblock threads stuck in ap_queue_pop() when a shutdown |
| * is pending. |
| * |
| * If workers_may_exit is set and this is ungraceful termination/ |
| * restart, we are bound to get an error on some systems (e.g., |
| * AIX, which sanity-checks mutex operations) since the queue |
| * may have already been cleaned up. Don't log the "error" if |
| * workers_may_exit is set. |
| */ |
| else if (APR_STATUS_IS_EINTR(rv)) { |
| goto worker_pop; |
| } |
| /* We got some other error. */ |
| else if (!workers_may_exit) { |
| ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ap_server_conf, |
| "ap_queue_pop failed"); |
| } |
| continue; |
| } |
| is_idle = 0; |
| worker_sockets[thread_slot] = csd; |
| bucket_alloc = apr_bucket_alloc_create(ptrans); |
| process_socket(ptrans, csd, process_slot, thread_slot, bucket_alloc); |
| worker_sockets[thread_slot] = NULL; |
| requests_this_child--; /* FIXME: should be synchronized - aaron */ |
| apr_pool_clear(ptrans); |
| last_ptrans = ptrans; |
| } |
| |
| ap_update_child_status_from_indexes(process_slot, thread_slot, |
| (dying) ? SERVER_DEAD : SERVER_GRACEFUL, (request_rec *) NULL); |
| |
| apr_thread_exit(thd, APR_SUCCESS); |
| return NULL; |
| } |
| |
| static int check_signal(int signum) |
| { |
| switch (signum) { |
| case SIGTERM: |
| case SIGINT: |
| return 1; |
| } |
| return 0; |
| } |
| |
| static void create_listener_thread(thread_starter *ts) |
| { |
| int my_child_num = ts->child_num_arg; |
| apr_threadattr_t *thread_attr = ts->threadattr; |
| proc_info *my_info; |
| apr_status_t rv; |
| |
| my_info = (proc_info *)malloc(sizeof(proc_info)); |
| my_info->pid = my_child_num; |
| my_info->tid = -1; /* listener thread doesn't have a thread slot */ |
| my_info->sd = 0; |
| rv = apr_thread_create(&ts->listener, thread_attr, listener_thread, |
| my_info, pchild); |
| if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_ALERT, rv, ap_server_conf, |
| "apr_thread_create: unable to create listener thread"); |
| /* In case system resources are maxxed out, we don't want |
| * Apache running away with the CPU trying to fork over and |
| * over and over again if we exit. |
| * XXX Jeff doesn't see how Apache is going to try to fork again since |
| * the exit code is APEXIT_CHILDFATAL |
| */ |
| apr_sleep(apr_time_from_sec(10)); |
| clean_child_exit(APEXIT_CHILDFATAL); |
| } |
| apr_os_thread_get(&listener_os_thread, ts->listener); |
| } |
| |
| /* XXX under some circumstances not understood, children can get stuck |
| * in start_threads forever trying to take over slots which will |
| * never be cleaned up; for now there is an APLOG_DEBUG message issued |
| * every so often when this condition occurs |
| */ |
| static void * APR_THREAD_FUNC start_threads(apr_thread_t *thd, void *dummy) |
| { |
| thread_starter *ts = dummy; |
| apr_thread_t **threads = ts->threads; |
| apr_threadattr_t *thread_attr = ts->threadattr; |
| int child_num_arg = ts->child_num_arg; |
| int my_child_num = child_num_arg; |
| proc_info *my_info; |
| apr_status_t rv; |
| int i; |
| int threads_created = 0; |
| int listener_started = 0; |
| int loops; |
| int prev_threads_created; |
| |
| /* We must create the fd queues before we start up the listener |
| * and worker threads. */ |
| worker_queue = apr_pcalloc(pchild, sizeof(*worker_queue)); |
| rv = ap_queue_init(worker_queue, ap_threads_per_child, pchild); |
| if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_ALERT, rv, ap_server_conf, |
| "ap_queue_init() failed"); |
| clean_child_exit(APEXIT_CHILDFATAL); |
| } |
| |
| rv = ap_queue_info_create(&worker_queue_info, pchild, |
| ap_threads_per_child); |
| if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_ALERT, rv, ap_server_conf, |
| "ap_queue_info_create() failed"); |
| clean_child_exit(APEXIT_CHILDFATAL); |
| } |
| |
| worker_sockets = apr_pcalloc(pchild, ap_threads_per_child |
| * sizeof(apr_socket_t *)); |
| |
| loops = prev_threads_created = 0; |
| while (1) { |
| /* ap_threads_per_child does not include the listener thread */ |
| for (i = 0; i < ap_threads_per_child; i++) { |
| int status = ap_scoreboard_image->servers[child_num_arg][i].status; |
| |
| if (status != SERVER_GRACEFUL && status != SERVER_DEAD) { |
| continue; |
| } |
| |
| my_info = (proc_info *)malloc(sizeof(proc_info)); |
| if (my_info == NULL) { |
| ap_log_error(APLOG_MARK, APLOG_ALERT, errno, ap_server_conf, |
| "malloc: out of memory"); |
| clean_child_exit(APEXIT_CHILDFATAL); |
| } |
| my_info->pid = my_child_num; |
| my_info->tid = i; |
| my_info->sd = 0; |
| |
| /* We are creating threads right now */ |
| ap_update_child_status_from_indexes(my_child_num, i, |
| SERVER_STARTING, NULL); |
| /* We let each thread update its own scoreboard entry. This is |
| * done because it lets us deal with tid better. |
| */ |
| rv = apr_thread_create(&threads[i], thread_attr, |
| worker_thread, my_info, pchild); |
| if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_ALERT, rv, ap_server_conf, |
| "apr_thread_create: unable to create worker thread"); |
| /* In case system resources are maxxed out, we don't want |
| Apache running away with the CPU trying to fork over and |
| over and over again if we exit. */ |
| apr_sleep(apr_time_from_sec(10)); |
| clean_child_exit(APEXIT_CHILDFATAL); |
| } |
| threads_created++; |
| } |
| /* Start the listener only when there are workers available */ |
| if (!listener_started && threads_created) { |
| create_listener_thread(ts); |
| listener_started = 1; |
| } |
| if (start_thread_may_exit || threads_created == ap_threads_per_child) { |
| break; |
| } |
| /* wait for previous generation to clean up an entry */ |
| apr_sleep(apr_time_from_sec(1)); |
| ++loops; |
| if (loops % 120 == 0) { /* every couple of minutes */ |
| if (prev_threads_created == threads_created) { |
| ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, |
| "child %" APR_PID_T_FMT " isn't taking over " |
| "slots very quickly (%d of %d)", |
| ap_my_pid, threads_created, ap_threads_per_child); |
| } |
| prev_threads_created = threads_created; |
| } |
| } |
| |
| /* What state should this child_main process be listed as in the |
| * scoreboard...? |
| * ap_update_child_status_from_indexes(my_child_num, i, SERVER_STARTING, |
| * (request_rec *) NULL); |
| * |
| * This state should be listed separately in the scoreboard, in some kind |
| * of process_status, not mixed in with the worker threads' status. |
| * "life_status" is almost right, but it's in the worker's structure, and |
| * the name could be clearer. gla |
| */ |
| apr_thread_exit(thd, APR_SUCCESS); |
| return NULL; |
| } |
| |
| static void join_workers(apr_thread_t *listener, apr_thread_t **threads) |
| { |
| int i; |
| apr_status_t rv, thread_rv; |
| |
| if (listener) { |
| int iter; |
| |
| /* deal with a rare timing window which affects waking up the |
| * listener thread... if the signal sent to the listener thread |
| * is delivered between the time it verifies that the |
| * listener_may_exit flag is clear and the time it enters a |
| * blocking syscall, the signal didn't do any good... work around |
| * that by sleeping briefly and sending it again |
| */ |
| |
| iter = 0; |
| while (iter < 10 && |
| #ifdef HAVE_PTHREAD_KILL |
| pthread_kill(*listener_os_thread, 0) |
| #else |
| kill(ap_my_pid, 0) |
| #endif |
| == 0) { |
| /* listener not dead yet */ |
| apr_sleep(apr_time_make(0, 500000)); |
| wakeup_listener(); |
| ++iter; |
| } |
| if (iter >= 10) { |
| ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, |
| "the listener thread didn't exit"); |
| } |
| else { |
| rv = apr_thread_join(&thread_rv, listener); |
| if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ap_server_conf, |
| "apr_thread_join: unable to join listener thread"); |
| } |
| } |
| } |
| |
| for (i = 0; i < ap_threads_per_child; i++) { |
| if (threads[i]) { /* if we ever created this thread */ |
| rv = apr_thread_join(&thread_rv, threads[i]); |
| if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ap_server_conf, |
| "apr_thread_join: unable to join worker " |
| "thread %d", |
| i); |
| } |
| } |
| } |
| } |
| |
| static void join_start_thread(apr_thread_t *start_thread_id) |
| { |
| apr_status_t rv, thread_rv; |
| |
| start_thread_may_exit = 1; /* tell it to give up in case it is still |
| * trying to take over slots from a |
| * previous generation |
| */ |
| rv = apr_thread_join(&thread_rv, start_thread_id); |
| if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ap_server_conf, |
| "apr_thread_join: unable to join the start " |
| "thread"); |
| } |
| } |
| |
| static void child_main(int child_num_arg) |
| { |
| apr_thread_t **threads; |
| apr_status_t rv; |
| thread_starter *ts; |
| apr_threadattr_t *thread_attr; |
| apr_thread_t *start_thread_id; |
| |
| mpm_state = AP_MPMQ_STARTING; /* for benefit of any hooks that run as this |
| * child initializes |
| */ |
| ap_my_pid = getpid(); |
| ap_fatal_signal_child_setup(ap_server_conf); |
| apr_pool_create(&pchild, pconf); |
| |
| /*stuff to do before we switch id's, so we have permissions.*/ |
| ap_reopen_scoreboard(pchild, NULL, 0); |
| |
| rv = SAFE_ACCEPT(apr_proc_mutex_child_init(&accept_mutex, ap_lock_fname, |
| pchild)); |
| if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf, |
| "Couldn't initialize cross-process lock in child"); |
| clean_child_exit(APEXIT_CHILDFATAL); |
| } |
| |
| if (unixd_setup_child()) { |
| clean_child_exit(APEXIT_CHILDFATAL); |
| } |
| |
| ap_run_child_init(pchild, ap_server_conf); |
| |
| /* done with init critical section */ |
| |
| /* Just use the standard apr_setup_signal_thread to block all signals |
| * from being received. The child processes no longer use signals for |
| * any communication with the parent process. |
| */ |
| rv = apr_setup_signal_thread(); |
| if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf, |
| "Couldn't initialize signal thread"); |
| clean_child_exit(APEXIT_CHILDFATAL); |
| } |
| |
| if (ap_max_requests_per_child) { |
| requests_this_child = ap_max_requests_per_child; |
| } |
| else { |
| /* coding a value of zero means infinity */ |
| requests_this_child = INT_MAX; |
| } |
| |
| /* Setup worker threads */ |
| |
| /* clear the storage; we may not create all our threads immediately, |
| * and we want a 0 entry to indicate a thread which was not created |
| */ |
| threads = (apr_thread_t **)calloc(1, |
| sizeof(apr_thread_t *) * ap_threads_per_child); |
| if (threads == NULL) { |
| ap_log_error(APLOG_MARK, APLOG_ALERT, errno, ap_server_conf, |
| "malloc: out of memory"); |
| clean_child_exit(APEXIT_CHILDFATAL); |
| } |
| |
| ts = (thread_starter *)apr_palloc(pchild, sizeof(*ts)); |
| |
| apr_threadattr_create(&thread_attr, pchild); |
| /* 0 means PTHREAD_CREATE_JOINABLE */ |
| apr_threadattr_detach_set(thread_attr, 0); |
| |
| if (ap_thread_stacksize != 0) { |
| apr_threadattr_stacksize_set(thread_attr, ap_thread_stacksize); |
| } |
| |
| ts->threads = threads; |
| ts->listener = NULL; |
| ts->child_num_arg = child_num_arg; |
| ts->threadattr = thread_attr; |
| |
| rv = apr_thread_create(&start_thread_id, thread_attr, start_threads, |
| ts, pchild); |
| if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_ALERT, rv, ap_server_conf, |
| "apr_thread_create: unable to create worker thread"); |
| /* In case system resources are maxxed out, we don't want |
| Apache running away with the CPU trying to fork over and |
| over and over again if we exit. */ |
| apr_sleep(apr_time_from_sec(10)); |
| clean_child_exit(APEXIT_CHILDFATAL); |
| } |
| |
| mpm_state = AP_MPMQ_RUNNING; |
| |
| /* If we are only running in one_process mode, we will want to |
| * still handle signals. */ |
| if (one_process) { |
| /* Block until we get a terminating signal. */ |
| apr_signal_thread(check_signal); |
| /* make sure the start thread has finished; signal_threads() |
| * and join_workers() depend on that |
| */ |
| /* XXX join_start_thread() won't be awakened if one of our |
| * threads encounters a critical error and attempts to |
| * shutdown this child |
| */ |
| join_start_thread(start_thread_id); |
| signal_threads(ST_UNGRACEFUL); /* helps us terminate a little more |
| * quickly than the dispatch of the signal thread |
| * beats the Pipe of Death and the browsers |
| */ |
| /* A terminating signal was received. Now join each of the |
| * workers to clean them up. |
| * If the worker already exited, then the join frees |
| * their resources and returns. |
| * If the worker hasn't exited, then this blocks until |
| * they have (then cleans up). |
| */ |
| join_workers(ts->listener, threads); |
| } |
| else { /* !one_process */ |
| /* remove SIGTERM from the set of blocked signals... if one of |
| * the other threads in the process needs to take us down |
| * (e.g., for MaxRequestsPerChild) it will send us SIGTERM |
| */ |
| unblock_signal(SIGTERM); |
| apr_signal(SIGTERM, dummy_signal_handler); |
| /* Watch for any messages from the parent over the POD */ |
| while (1) { |
| rv = ap_mpm_pod_check(pod); |
| if (rv == AP_NORESTART) { |
| /* see if termination was triggered while we slept */ |
| switch(terminate_mode) { |
| case ST_GRACEFUL: |
| rv = AP_GRACEFUL; |
| break; |
| case ST_UNGRACEFUL: |
| rv = AP_RESTART; |
| break; |
| } |
| } |
| if (rv == AP_GRACEFUL || rv == AP_RESTART) { |
| /* make sure the start thread has finished; |
| * signal_threads() and join_workers depend on that |
| */ |
| join_start_thread(start_thread_id); |
| signal_threads(rv == AP_GRACEFUL ? ST_GRACEFUL : ST_UNGRACEFUL); |
| break; |
| } |
| } |
| |
| /* A terminating signal was received. Now join each of the |
| * workers to clean them up. |
| * If the worker already exited, then the join frees |
| * their resources and returns. |
| * If the worker hasn't exited, then this blocks until |
| * they have (then cleans up). |
| */ |
| join_workers(ts->listener, threads); |
| } |
| |
| free(threads); |
| |
| clean_child_exit(resource_shortage ? APEXIT_CHILDSICK : 0); |
| } |
| |
| static int make_child(server_rec *s, int slot) |
| { |
| int pid; |
| |
| if (slot + 1 > ap_max_daemons_limit) { |
| ap_max_daemons_limit = slot + 1; |
| } |
| |
| if (one_process) { |
| set_signals(); |
| ap_scoreboard_image->parent[slot].pid = getpid(); |
| child_main(slot); |
| } |
| |
| if ((pid = fork()) == -1) { |
| ap_log_error(APLOG_MARK, APLOG_ERR, errno, s, |
| "fork: Unable to fork new process"); |
| |
| /* fork didn't succeed. Fix the scoreboard or else |
| * it will say SERVER_STARTING forever and ever |
| */ |
| ap_update_child_status_from_indexes(slot, 0, SERVER_DEAD, NULL); |
| |
| /* In case system resources are maxxed out, we don't want |
| Apache running away with the CPU trying to fork over and |
| over and over again. */ |
| apr_sleep(apr_time_from_sec(10)); |
| |
| return -1; |
| } |
| |
| if (!pid) { |
| #ifdef HAVE_BINDPROCESSOR |
| /* By default, AIX binds to a single processor. This bit unbinds |
| * children which will then bind to another CPU. |
| */ |
| int status = bindprocessor(BINDPROCESS, (int)getpid(), |
| PROCESSOR_CLASS_ANY); |
| if (status != OK) |
| ap_log_error(APLOG_MARK, APLOG_WARNING, errno, |
| ap_server_conf, |
| "processor unbind failed %d", status); |
| #endif |
| RAISE_SIGSTOP(MAKE_CHILD); |
| |
| apr_signal(SIGTERM, just_die); |
| child_main(slot); |
| |
| clean_child_exit(0); |
| } |
| /* else */ |
| ap_scoreboard_image->parent[slot].quiescing = 0; |
| ap_scoreboard_image->parent[slot].pid = pid; |
| return 0; |
| } |
| |
| /* start up a bunch of children */ |
| static void startup_children(int number_to_start) |
| { |
| int i; |
| |
| for (i = 0; number_to_start && i < ap_daemons_limit; ++i) { |
| if (ap_scoreboard_image->parent[i].pid != 0) { |
| continue; |
| } |
| if (make_child(ap_server_conf, i) < 0) { |
| break; |
| } |
| --number_to_start; |
| } |
| } |
| |
| |
| /* |
| * idle_spawn_rate is the number of children that will be spawned on the |
| * next maintenance cycle if there aren't enough idle servers. It is |
| * doubled up to MAX_SPAWN_RATE, and reset only when a cycle goes by |
| * without the need to spawn. |
| */ |
| static int idle_spawn_rate = 1; |
| #ifndef MAX_SPAWN_RATE |
| #define MAX_SPAWN_RATE (32) |
| #endif |
| static int hold_off_on_exponential_spawning; |
| |
| static void perform_idle_server_maintenance(void) |
| { |
| int i, j; |
| int idle_thread_count; |
| worker_score *ws; |
| process_score *ps; |
| int free_length; |
| int totally_free_length = 0; |
| int free_slots[MAX_SPAWN_RATE]; |
| int last_non_dead; |
| int total_non_dead; |
| |
| /* initialize the free_list */ |
| free_length = 0; |
| |
| idle_thread_count = 0; |
| last_non_dead = -1; |
| total_non_dead = 0; |
| |
| for (i = 0; i < ap_daemons_limit; ++i) { |
| /* Initialization to satisfy the compiler. It doesn't know |
| * that ap_threads_per_child is always > 0 */ |
| int status = SERVER_DEAD; |
| int any_dying_threads = 0; |
| int any_dead_threads = 0; |
| int all_dead_threads = 1; |
| |
| if (i >= ap_max_daemons_limit && totally_free_length == idle_spawn_rate) |
| break; |
| ps = &ap_scoreboard_image->parent[i]; |
| for (j = 0; j < ap_threads_per_child; j++) { |
| ws = &ap_scoreboard_image->servers[i][j]; |
| status = ws->status; |
| |
| /* XXX any_dying_threads is probably no longer needed GLA */ |
| any_dying_threads = any_dying_threads || |
| (status == SERVER_GRACEFUL); |
| any_dead_threads = any_dead_threads || (status == SERVER_DEAD); |
| all_dead_threads = all_dead_threads && |
| (status == SERVER_DEAD || |
| status == SERVER_GRACEFUL); |
| |
| /* We consider a starting server as idle because we started it |
| * at least a cycle ago, and if it still hasn't finished starting |
| * then we're just going to swamp things worse by forking more. |
| * So we hopefully won't need to fork more if we count it. |
| * This depends on the ordering of SERVER_READY and SERVER_STARTING. |
| */ |
| if (status <= SERVER_READY && status != SERVER_DEAD && |
| !ps->quiescing && |
| ps->generation == ap_my_generation && |
| /* XXX the following shouldn't be necessary if we clean up |
| * properly after seg faults, but we're not yet GLA |
| */ |
| ps->pid != 0) { |
| ++idle_thread_count; |
| } |
| } |
| if (any_dead_threads && totally_free_length < idle_spawn_rate |
| && free_length < MAX_SPAWN_RATE |
| && (!ps->pid /* no process in the slot */ |
| || ps->quiescing)) { /* or at least one is going away */ |
| if (all_dead_threads) { |
| /* great! we prefer these, because the new process can |
| * start more threads sooner. So prioritize this slot |
| * by putting it ahead of any slots with active threads. |
| * |
| * first, make room by moving a slot that's potentially still |
| * in use to the end of the array |
| */ |
| free_slots[free_length] = free_slots[totally_free_length]; |
| free_slots[totally_free_length++] = i; |
| } |
| else { |
| /* slot is still in use - back of the bus |
| */ |
| free_slots[free_length] = i; |
| } |
| ++free_length; |
| } |
| /* XXX if (!ps->quiescing) is probably more reliable GLA */ |
| if (!any_dying_threads) { |
| last_non_dead = i; |
| ++total_non_dead; |
| } |
| } |
| ap_max_daemons_limit = last_non_dead + 1; |
| |
| if (idle_thread_count > max_spare_threads) { |
| /* Kill off one child */ |
| ap_mpm_pod_signal(pod, TRUE); |
| idle_spawn_rate = 1; |
| } |
| else if (idle_thread_count < min_spare_threads) { |
| /* terminate the free list */ |
| if (free_length == 0) { |
| /* only report this condition once */ |
| static int reported = 0; |
| |
| if (!reported) { |
| ap_log_error(APLOG_MARK, APLOG_ERR, 0, |
| ap_server_conf, |
| "server reached MaxClients setting, consider" |
| " raising the MaxClients setting"); |
| reported = 1; |
| } |
| idle_spawn_rate = 1; |
| } |
| else { |
| if (free_length > idle_spawn_rate) { |
| free_length = idle_spawn_rate; |
| } |
| if (idle_spawn_rate >= 8) { |
| ap_log_error(APLOG_MARK, APLOG_INFO, 0, |
| ap_server_conf, |
| "server seems busy, (you may need " |
| "to increase StartServers, ThreadsPerChild " |
| "or Min/MaxSpareThreads), " |
| "spawning %d children, there are around %d idle " |
| "threads, and %d total children", free_length, |
| idle_thread_count, total_non_dead); |
| } |
| for (i = 0; i < free_length; ++i) { |
| make_child(ap_server_conf, free_slots[i]); |
| } |
| /* the next time around we want to spawn twice as many if this |
| * wasn't good enough, but not if we've just done a graceful |
| */ |
| if (hold_off_on_exponential_spawning) { |
| --hold_off_on_exponential_spawning; |
| } |
| else if (idle_spawn_rate < MAX_SPAWN_RATE) { |
| idle_spawn_rate *= 2; |
| } |
| } |
| } |
| else { |
| idle_spawn_rate = 1; |
| } |
| } |
| |
| static void server_main_loop(int remaining_children_to_start) |
| { |
| int child_slot; |
| apr_exit_why_e exitwhy; |
| int status, processed_status; |
| apr_proc_t pid; |
| int i; |
| |
| while (!restart_pending && !shutdown_pending) { |
| ap_wait_or_timeout(&exitwhy, &status, &pid, pconf); |
| |
| if (pid.pid != -1) { |
| processed_status = ap_process_child_status(&pid, exitwhy, status); |
| if (processed_status == APEXIT_CHILDFATAL) { |
| shutdown_pending = 1; |
| child_fatal = 1; |
| return; |
| } |
| /* non-fatal death... note that it's gone in the scoreboard. */ |
| child_slot = find_child_by_pid(&pid); |
| if (child_slot >= 0) { |
| for (i = 0; i < ap_threads_per_child; i++) |
| ap_update_child_status_from_indexes(child_slot, i, SERVER_DEAD, |
| (request_rec *) NULL); |
| |
| ap_scoreboard_image->parent[child_slot].pid = 0; |
| ap_scoreboard_image->parent[child_slot].quiescing = 0; |
| if (processed_status == APEXIT_CHILDSICK) { |
| /* resource shortage, minimize the fork rate */ |
| idle_spawn_rate = 1; |
| } |
| else if (remaining_children_to_start |
| && child_slot < ap_daemons_limit) { |
| /* we're still doing a 1-for-1 replacement of dead |
| * children with new children |
| */ |
| make_child(ap_server_conf, child_slot); |
| --remaining_children_to_start; |
| } |
| #if APR_HAS_OTHER_CHILD |
| } |
| else if (apr_proc_other_child_alert(&pid, APR_OC_REASON_DEATH, |
| status) == 0) { |
| /* handled */ |
| #endif |
| } |
| else if (is_graceful) { |
| /* Great, we've probably just lost a slot in the |
| * scoreboard. Somehow we don't know about this child. |
| */ |
| ap_log_error(APLOG_MARK, APLOG_WARNING, 0, |
| ap_server_conf, |
| "long lost child came home! (pid %ld)", |
| (long)pid.pid); |
| } |
| /* Don't perform idle maintenance when a child dies, |
| * only do it when there's a timeout. Remember only a |
| * finite number of children can die, and it's pretty |
| * pathological for a lot to die suddenly. |
| */ |
| continue; |
| } |
| else if (remaining_children_to_start) { |
| /* we hit a 1 second timeout in which none of the previous |
| * generation of children needed to be reaped... so assume |
| * they're all done, and pick up the slack if any is left. |
| */ |
| startup_children(remaining_children_to_start); |
| remaining_children_to_start = 0; |
| /* In any event we really shouldn't do the code below because |
| * few of the servers we just started are in the IDLE state |
| * yet, so we'd mistakenly create an extra server. |
| */ |
| continue; |
| } |
| |
| perform_idle_server_maintenance(); |
| } |
| } |
| |
| int ap_mpm_run(apr_pool_t *_pconf, apr_pool_t *plog, server_rec *s) |
| { |
| int remaining_children_to_start; |
| apr_status_t rv; |
| |
| ap_log_pid(pconf, ap_pid_fname); |
| |
| first_server_limit = server_limit; |
| first_thread_limit = thread_limit; |
| if (changed_limit_at_restart) { |
| ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, |
| "WARNING: Attempt to change ServerLimit or ThreadLimit " |
| "ignored during restart"); |
| changed_limit_at_restart = 0; |
| } |
| |
| /* Initialize cross-process accept lock */ |
| ap_lock_fname = apr_psprintf(_pconf, "%s.%" APR_PID_T_FMT, |
| ap_server_root_relative(_pconf, ap_lock_fname), |
| ap_my_pid); |
| |
| rv = apr_proc_mutex_create(&accept_mutex, ap_lock_fname, |
| ap_accept_lock_mech, _pconf); |
| if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s, |
| "Couldn't create accept lock"); |
| mpm_state = AP_MPMQ_STOPPING; |
| return 1; |
| } |
| |
| #if APR_USE_SYSVSEM_SERIALIZE |
| if (ap_accept_lock_mech == APR_LOCK_DEFAULT || |
| ap_accept_lock_mech == APR_LOCK_SYSVSEM) { |
| #else |
| if (ap_accept_lock_mech == APR_LOCK_SYSVSEM) { |
| #endif |
| rv = unixd_set_proc_mutex_perms(accept_mutex); |
| if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s, |
| "Couldn't set permissions on cross-process lock; " |
| "check User and Group directives"); |
| mpm_state = AP_MPMQ_STOPPING; |
| return 1; |
| } |
| } |
| |
| if (!is_graceful) { |
| if (ap_run_pre_mpm(s->process->pool, SB_SHARED) != OK) { |
| mpm_state = AP_MPMQ_STOPPING; |
| return 1; |
| } |
| /* fix the generation number in the global score; we just got a new, |
| * cleared scoreboard |
| */ |
| ap_scoreboard_image->global->running_generation = ap_my_generation; |
| } |
| |
| set_signals(); |
| /* Don't thrash... */ |
| if (max_spare_threads < min_spare_threads + ap_threads_per_child) |
| max_spare_threads = min_spare_threads + ap_threads_per_child; |
| |
| /* If we're doing a graceful_restart then we're going to see a lot |
| * of children exiting immediately when we get into the main loop |
| * below (because we just sent them AP_SIG_GRACEFUL). This happens pretty |
| * rapidly... and for each one that exits we'll start a new one until |
| * we reach at least daemons_min_free. But we may be permitted to |
| * start more than that, so we'll just keep track of how many we're |
| * supposed to start up without the 1 second penalty between each fork. |
| */ |
| remaining_children_to_start = ap_daemons_to_start; |
| if (remaining_children_to_start > ap_daemons_limit) { |
| remaining_children_to_start = ap_daemons_limit; |
| } |
| if (!is_graceful) { |
| startup_children(remaining_children_to_start); |
| remaining_children_to_start = 0; |
| } |
| else { |
| /* give the system some time to recover before kicking into |
| * exponential mode */ |
| hold_off_on_exponential_spawning = 10; |
| } |
| |
| ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf, |
| "%s configured -- resuming normal operations", |
| ap_get_server_version()); |
| ap_log_error(APLOG_MARK, APLOG_INFO, 0, ap_server_conf, |
| "Server built: %s", ap_get_server_built()); |
| #ifdef AP_MPM_WANT_SET_ACCEPT_LOCK_MECH |
| ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, |
| "AcceptMutex: %s (default: %s)", |
| apr_proc_mutex_name(accept_mutex), |
| apr_proc_mutex_defname()); |
| #endif |
| restart_pending = shutdown_pending = 0; |
| mpm_state = AP_MPMQ_RUNNING; |
| |
| server_main_loop(remaining_children_to_start); |
| mpm_state = AP_MPMQ_STOPPING; |
| |
| if (shutdown_pending) { |
| /* Time to gracefully shut down: |
| * Kill child processes, tell them to call child_exit, etc... |
| * (By "gracefully" we don't mean graceful in the same sense as |
| * "apachectl graceful" where we allow old connections to finish.) |
| */ |
| ap_mpm_pod_killpg(pod, ap_daemons_limit, FALSE); |
| ap_reclaim_child_processes(1); /* Start with SIGTERM */ |
| |
| if (!child_fatal) { |
| /* cleanup pid file on normal shutdown */ |
| const char *pidfile = NULL; |
| pidfile = ap_server_root_relative (pconf, ap_pid_fname); |
| if ( pidfile != NULL && unlink(pidfile) == 0) |
| ap_log_error(APLOG_MARK, APLOG_INFO, 0, |
| ap_server_conf, |
| "removed PID file %s (pid=%ld)", |
| pidfile, (long)getpid()); |
| |
| ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, |
| ap_server_conf, "caught SIGTERM, shutting down"); |
| } |
| return 1; |
| } |
| |
| /* we've been told to restart */ |
| apr_signal(SIGHUP, SIG_IGN); |
| |
| if (one_process) { |
| /* not worth thinking about */ |
| return 1; |
| } |
| |
| /* advance to the next generation */ |
| /* XXX: we really need to make sure this new generation number isn't in |
| * use by any of the children. |
| */ |
| ++ap_my_generation; |
| ap_scoreboard_image->global->running_generation = ap_my_generation; |
| |
| if (is_graceful) { |
| ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf, |
| AP_SIG_GRACEFUL_STRING " received. Doing graceful restart"); |
| /* wake up the children...time to die. But we'll have more soon */ |
| ap_mpm_pod_killpg(pod, ap_daemons_limit, TRUE); |
| |
| |
| /* This is mostly for debugging... so that we know what is still |
| * gracefully dealing with existing request. |
| */ |
| |
| } |
| else { |
| /* Kill 'em all. Since the child acts the same on the parents SIGTERM |
| * and a SIGHUP, we may as well use the same signal, because some user |
| * pthreads are stealing signals from us left and right. |
| */ |
| ap_mpm_pod_killpg(pod, ap_daemons_limit, FALSE); |
| |
| ap_reclaim_child_processes(1); /* Start with SIGTERM */ |
| ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf, |
| "SIGHUP received. Attempting to restart"); |
| } |
| |
| return 0; |
| } |
| |
| /* This really should be a post_config hook, but the error log is already |
| * redirected by that point, so we need to do this in the open_logs phase. |
| */ |
| static int worker_open_logs(apr_pool_t *p, apr_pool_t *plog, apr_pool_t *ptemp, server_rec *s) |
| { |
| apr_status_t rv; |
| |
| pconf = p; |
| ap_server_conf = s; |
| |
| if ((num_listensocks = ap_setup_listeners(ap_server_conf)) < 1) { |
| ap_log_error(APLOG_MARK, APLOG_ALERT|APLOG_STARTUP, 0, |
| NULL, "no listening sockets available, shutting down"); |
| return DONE; |
| } |
| |
| if (!one_process) { |
| if ((rv = ap_mpm_pod_open(pconf, &pod))) { |
| ap_log_error(APLOG_MARK, APLOG_CRIT|APLOG_STARTUP, rv, NULL, |
| "Could not open pipe-of-death."); |
| return DONE; |
| } |
| } |
| return OK; |
| } |
| |
| static int worker_pre_config(apr_pool_t *pconf, apr_pool_t *plog, |
| apr_pool_t *ptemp) |
| { |
| static int restart_num = 0; |
| int no_detach, debug, foreground; |
| ap_directive_t *pdir; |
| ap_directive_t *max_clients = NULL; |
| apr_status_t rv; |
| |
| mpm_state = AP_MPMQ_STARTING; |
| |
| /* make sure that "ThreadsPerChild" gets set before "MaxClients" */ |
| for (pdir = ap_conftree; pdir != NULL; pdir = pdir->next) { |
| if (strncasecmp(pdir->directive, "ThreadsPerChild", 15) == 0) { |
| if (!max_clients) { |
| break; /* we're in the clear, got ThreadsPerChild first */ |
| } |
| else { |
| /* now to swap the data */ |
| ap_directive_t temp; |
| |
| temp.directive = pdir->directive; |
| temp.args = pdir->args; |
| /* Make sure you don't change 'next', or you may get loops! */ |
| /* XXX: first_child, parent, and data can never be set |
| * for these directives, right? -aaron */ |
| temp.filename = pdir->filename; |
| temp.line_num = pdir->line_num; |
| |
| pdir->directive = max_clients->directive; |
| pdir->args = max_clients->args; |
| pdir->filename = max_clients->filename; |
| pdir->line_num = max_clients->line_num; |
| |
| max_clients->directive = temp.directive; |
| max_clients->args = temp.args; |
| max_clients->filename = temp.filename; |
| max_clients->line_num = temp.line_num; |
| break; |
| } |
| } |
| else if (!max_clients |
| && strncasecmp(pdir->directive, "MaxClients", 10) == 0) { |
| max_clients = pdir; |
| } |
| } |
| |
| debug = ap_exists_config_define("DEBUG"); |
| |
| if (debug) { |
| foreground = one_process = 1; |
| no_detach = 0; |
| } |
| else { |
| one_process = ap_exists_config_define("ONE_PROCESS"); |
| no_detach = ap_exists_config_define("NO_DETACH"); |
| foreground = ap_exists_config_define("FOREGROUND"); |
| } |
| |
| /* sigh, want this only the second time around */ |
| if (restart_num++ == 1) { |
| is_graceful = 0; |
| |
| if (!one_process && !foreground) { |
| rv = apr_proc_detach(no_detach ? APR_PROC_DETACH_FOREGROUND |
| : APR_PROC_DETACH_DAEMONIZE); |
| if (rv != APR_SUCCESS) { |
| ap_log_error(APLOG_MARK, APLOG_CRIT, rv, NULL, |
| "apr_proc_detach failed"); |
| return HTTP_INTERNAL_SERVER_ERROR; |
| } |
| } |
| parent_pid = ap_my_pid = getpid(); |
| } |
| |
| unixd_pre_config(ptemp); |
| ap_listen_pre_config(); |
| ap_daemons_to_start = DEFAULT_START_DAEMON; |
| min_spare_threads = DEFAULT_MIN_FREE_DAEMON * DEFAULT_THREADS_PER_CHILD; |
| max_spare_threads = DEFAULT_MAX_FREE_DAEMON * DEFAULT_THREADS_PER_CHILD; |
| ap_daemons_limit = server_limit; |
| ap_threads_per_child = DEFAULT_THREADS_PER_CHILD; |
| ap_pid_fname = DEFAULT_PIDLOG; |
| ap_lock_fname = DEFAULT_LOCKFILE; |
| ap_max_requests_per_child = DEFAULT_MAX_REQUESTS_PER_CHILD; |
| ap_extended_status = 0; |
| #ifdef AP_MPM_WANT_SET_MAX_MEM_FREE |
| ap_max_mem_free = APR_ALLOCATOR_MAX_FREE_UNLIMITED; |
| #endif |
| |
| apr_cpystrn(ap_coredump_dir, ap_server_root, sizeof(ap_coredump_dir)); |
| |
| return OK; |
| } |
| |
| static void worker_hooks(apr_pool_t *p) |
| { |
| /* The worker open_logs phase must run before the core's, or stderr |
| * will be redirected to a file, and the messages won't print to the |
| * console. |
| */ |
| static const char *const aszSucc[] = {"core.c", NULL}; |
| one_process = 0; |
| |
| ap_hook_open_logs(worker_open_logs, NULL, aszSucc, APR_HOOK_MIDDLE); |
| /* we need to set the MPM state before other pre-config hooks use MPM query |
| * to retrieve it, so register as REALLY_FIRST |
| */ |
| ap_hook_pre_config(worker_pre_config, NULL, NULL, APR_HOOK_REALLY_FIRST); |
| } |
| |
| static const char *set_daemons_to_start(cmd_parms *cmd, void *dummy, |
| const char *arg) |
| { |
| const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); |
| if (err != NULL) { |
| return err; |
| } |
| |
| ap_daemons_to_start = atoi(arg); |
| return NULL; |
| } |
| |
| static const char *set_min_spare_threads(cmd_parms *cmd, void *dummy, |
| const char *arg) |
| { |
| const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); |
| if (err != NULL) { |
| return err; |
| } |
| |
| min_spare_threads = atoi(arg); |
| if (min_spare_threads <= 0) { |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| "WARNING: detected MinSpareThreads set to non-positive."); |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| "Resetting to 1 to avoid almost certain Apache failure."); |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| "Please read the documentation."); |
| min_spare_threads = 1; |
| } |
| |
| return NULL; |
| } |
| |
| static const char *set_max_spare_threads(cmd_parms *cmd, void *dummy, |
| const char *arg) |
| { |
| const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); |
| if (err != NULL) { |
| return err; |
| } |
| |
| max_spare_threads = atoi(arg); |
| return NULL; |
| } |
| |
| static const char *set_max_clients (cmd_parms *cmd, void *dummy, |
| const char *arg) |
| { |
| int max_clients; |
| const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); |
| if (err != NULL) { |
| return err; |
| } |
| |
| /* It is ok to use ap_threads_per_child here because we are |
| * sure that it gets set before MaxClients in the pre_config stage. */ |
| max_clients = atoi(arg); |
| if (max_clients < ap_threads_per_child) { |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| "WARNING: MaxClients (%d) must be at least as large", |
| max_clients); |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| " as ThreadsPerChild (%d). Automatically", |
| ap_threads_per_child); |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| " increasing MaxClients to %d.", |
| ap_threads_per_child); |
| max_clients = ap_threads_per_child; |
| } |
| ap_daemons_limit = max_clients / ap_threads_per_child; |
| if ((max_clients > 0) && (max_clients % ap_threads_per_child)) { |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| "WARNING: MaxClients (%d) is not an integer multiple", |
| max_clients); |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| " of ThreadsPerChild (%d), lowering MaxClients to %d", |
| ap_threads_per_child, |
| ap_daemons_limit * ap_threads_per_child); |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| " for a maximum of %d child processes,", |
| ap_daemons_limit); |
| max_clients = ap_daemons_limit * ap_threads_per_child; |
| } |
| if (ap_daemons_limit > server_limit) { |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| "WARNING: MaxClients of %d would require %d servers,", |
| max_clients, ap_daemons_limit); |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| " and would exceed the ServerLimit value of %d.", |
| server_limit); |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| " Automatically lowering MaxClients to %d. To increase,", |
| server_limit * ap_threads_per_child); |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| " please see the ServerLimit directive."); |
| ap_daemons_limit = server_limit; |
| } |
| else if (ap_daemons_limit < 1) { |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| "WARNING: Require MaxClients > 0, setting to 1"); |
| ap_daemons_limit = 1; |
| } |
| return NULL; |
| } |
| |
| static const char *set_threads_per_child (cmd_parms *cmd, void *dummy, |
| const char *arg) |
| { |
| const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); |
| if (err != NULL) { |
| return err; |
| } |
| |
| ap_threads_per_child = atoi(arg); |
| if (ap_threads_per_child > thread_limit) { |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| "WARNING: ThreadsPerChild of %d exceeds ThreadLimit " |
| "value of %d", ap_threads_per_child, |
| thread_limit); |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| "threads, lowering ThreadsPerChild to %d. To increase, please" |
| " see the", thread_limit); |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| " ThreadLimit directive."); |
| ap_threads_per_child = thread_limit; |
| } |
| else if (ap_threads_per_child < 1) { |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| "WARNING: Require ThreadsPerChild > 0, setting to 1"); |
| ap_threads_per_child = 1; |
| } |
| return NULL; |
| } |
| |
| static const char *set_server_limit (cmd_parms *cmd, void *dummy, const char *arg) |
| { |
| int tmp_server_limit; |
| |
| const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); |
| if (err != NULL) { |
| return err; |
| } |
| |
| tmp_server_limit = atoi(arg); |
| /* you cannot change ServerLimit across a restart; ignore |
| * any such attempts |
| */ |
| if (first_server_limit && |
| tmp_server_limit != server_limit) { |
| /* how do we log a message? the error log is a bit bucket at this |
| * point; we'll just have to set a flag so that ap_mpm_run() |
| * logs a warning later |
| */ |
| changed_limit_at_restart = 1; |
| return NULL; |
| } |
| server_limit = tmp_server_limit; |
| |
| if (server_limit > MAX_SERVER_LIMIT) { |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| "WARNING: ServerLimit of %d exceeds compile time limit " |
| "of %d servers,", server_limit, MAX_SERVER_LIMIT); |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| " lowering ServerLimit to %d.", MAX_SERVER_LIMIT); |
| server_limit = MAX_SERVER_LIMIT; |
| } |
| else if (server_limit < 1) { |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| "WARNING: Require ServerLimit > 0, setting to 1"); |
| server_limit = 1; |
| } |
| return NULL; |
| } |
| |
| static const char *set_thread_limit (cmd_parms *cmd, void *dummy, const char *arg) |
| { |
| int tmp_thread_limit; |
| |
| const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); |
| if (err != NULL) { |
| return err; |
| } |
| |
| tmp_thread_limit = atoi(arg); |
| /* you cannot change ThreadLimit across a restart; ignore |
| * any such attempts |
| */ |
| if (first_thread_limit && |
| tmp_thread_limit != thread_limit) { |
| /* how do we log a message? the error log is a bit bucket at this |
| * point; we'll just have to set a flag so that ap_mpm_run() |
| * logs a warning later |
| */ |
| changed_limit_at_restart = 1; |
| return NULL; |
| } |
| thread_limit = tmp_thread_limit; |
| |
| if (thread_limit > MAX_THREAD_LIMIT) { |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| "WARNING: ThreadLimit of %d exceeds compile time limit " |
| "of %d servers,", thread_limit, MAX_THREAD_LIMIT); |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| " lowering ThreadLimit to %d.", MAX_THREAD_LIMIT); |
| thread_limit = MAX_THREAD_LIMIT; |
| } |
| else if (thread_limit < 1) { |
| ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, |
| "WARNING: Require ThreadLimit > 0, setting to 1"); |
| thread_limit = 1; |
| } |
| return NULL; |
| } |
| |
| static const command_rec worker_cmds[] = { |
| UNIX_DAEMON_COMMANDS, |
| LISTEN_COMMANDS, |
| AP_INIT_TAKE1("StartServers", set_daemons_to_start, NULL, RSRC_CONF, |
| "Number of child processes launched at server startup"), |
| AP_INIT_TAKE1("MinSpareThreads", set_min_spare_threads, NULL, RSRC_CONF, |
| "Minimum number of idle threads, to handle request spikes"), |
| AP_INIT_TAKE1("MaxSpareThreads", set_max_spare_threads, NULL, RSRC_CONF, |
| "Maximum number of idle threads"), |
| AP_INIT_TAKE1("MaxClients", set_max_clients, NULL, RSRC_CONF, |
| "Maximum number of threads alive at the same time"), |
| AP_INIT_TAKE1("ThreadsPerChild", set_threads_per_child, NULL, RSRC_CONF, |
| "Number of threads each child creates"), |
| AP_INIT_TAKE1("ServerLimit", set_server_limit, NULL, RSRC_CONF, |
| "Maximum number of child processes for this run of Apache"), |
| AP_INIT_TAKE1("ThreadLimit", set_thread_limit, NULL, RSRC_CONF, |
| "Maximum number of worker threads per child process for this run of Apache - Upper limit for ThreadsPerChild"), |
| { NULL } |
| }; |
| |
| module AP_MODULE_DECLARE_DATA mpm_worker_module = { |
| MPM20_MODULE_STUFF, |
| ap_mpm_rewrite_args, /* hook to run before apache parses args */ |
| NULL, /* create per-directory config structure */ |
| NULL, /* merge per-directory config structures */ |
| NULL, /* create per-server config structure */ |
| NULL, /* merge per-server config structures */ |
| worker_cmds, /* command apr_table_t */ |
| worker_hooks /* register_hooks */ |
| }; |
| |
