/* Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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. */ /** * This MPM tries to fix the 'keep alive problem' in HTTP. * * After a client completes the first request, the client can keep the * connection open to send more requests with the same socket. This can save * signifigant overhead in creating TCP connections. However, the major * disadvantage is that Apache traditionally keeps an entire child * process/thread waiting for data from the client. To solve this problem, * this MPM has a dedicated thread for handling both the Listenting sockets, * and all sockets that are in a Keep Alive status. * * The MPM assumes the underlying apr_pollset implementation is somewhat * threadsafe. This currently is only compatible with KQueue and EPoll. This * enables the MPM to avoid extra high level locking or having to wake up the * listener thread when a keep-alive socket needs to be sent to it. * * This MPM not preform well on older platforms that do not have very good * threading, like Linux with a 2.4 kernel, but this does not matter, since we * require EPoll or KQueue. * * For FreeBSD, use 5.3. It is possible to run this MPM on FreeBSD 5.2.1, if * you use libkse (see `man libmap.conf`). * * For NetBSD, use at least 2.0. * * For Linux, you should use a 2.6 kernel, and make sure your glibc has epoll * support compiled in. * */ #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_poll.h" #include "apr_ring.h" #include "apr_queue.h" #include "apr_atomic.h" #define APR_WANT_STRFUNC #include "apr_want.h" #include "apr_env.h" #if APR_HAVE_UNISTD_H #include #endif #if APR_HAVE_SYS_SOCKET_H #include #endif #if APR_HAVE_SYS_WAIT_H #include #endif #ifdef HAVE_SYS_PROCESSOR_H #include /* for bindprocessor() */ #endif #if !APR_HAS_THREADS #error The EventOpt MPM requires APR threads, but they are unavailable. #endif #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 "mpm_common.h" #include "ap_listen.h" #include "scoreboard.h" #include "fdqueue.h" #include "mpm_default.h" #include "http_vhost.h" #include "unixd.h" #include #include /* for INT_MAX */ #include "equeue.h" #if HAVE_SERF #include "mod_serf.h" #include "serf.h" #endif /* 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 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 100000 #endif #define MPM_CHILD_PID(i) (ap_scoreboard_image->parent[i].pid) #ifndef MAX_SECS_TO_LINGER #define MAX_SECS_TO_LINGER 30 #endif #define SECONDS_TO_LINGER 2 /* * Actual definitions of config globals */ #ifndef DEFAULT_WORKER_FACTOR #define DEFAULT_WORKER_FACTOR 2 #endif #define WORKER_FACTOR_SCALE 16 /* scale factor to allow fractional values */ static unsigned int worker_factor = DEFAULT_WORKER_FACTOR * WORKER_FACTOR_SCALE; static int 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 max_workers = 0; static int server_limit = 0; static int thread_limit = 0; 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 apr_uint32_t connection_count = 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; typedef enum { TIMEOUT_WRITE_COMPLETION, TIMEOUT_KEEPALIVE, TIMEOUT_LINGER, TIMEOUT_SHORT_LINGER } timeout_type_e; struct event_conn_state_t { /** APR_RING of expiration timeouts */ APR_RING_ENTRY(event_conn_state_t) timeout_list; /** the expiration time of the next keepalive timeout */ apr_time_t expiration_time; /** connection record this struct refers to */ conn_rec *c; /** memory pool to allocate from */ apr_pool_t *p; /** bucket allocator */ apr_bucket_alloc_t *bucket_alloc; /** poll file descriptor information */ apr_pollfd_t pfd; /** public parts of the connection state */ conn_state_t pub; }; typedef struct pollset_op_t { timeout_type_e timeout_type; event_conn_state_t *cs; const char *tag; } pollset_op_t; APR_RING_HEAD(timeout_head_t, event_conn_state_t); struct timeout_queue { struct timeout_head_t head; int count; const char *tag; }; /* * Several timeout queues that use different timeouts, so that we always can * simply append to the end. * write_completion_q uses TimeOut * keepalive_q uses KeepAliveTimeOut * linger_q uses MAX_SECS_TO_LINGER * short_linger_q uses SECONDS_TO_LINGER */ static struct timeout_queue write_completion_q, keepalive_q, linger_q, short_linger_q; static apr_pollfd_t *listener_pollfd; /* * Macros for accessing struct timeout_queue. * For TO_QUEUE_APPEND and TO_QUEUE_REMOVE, timeout_mutex must be held. */ #define TO_QUEUE_APPEND(q, el) \ do { \ APR_RING_INSERT_TAIL(&(q).head, el, event_conn_state_t, timeout_list); \ (q).count++; \ } while (0) #define TO_QUEUE_REMOVE(q, el) \ do { \ APR_RING_REMOVE(el, timeout_list); \ (q).count--; \ } while (0) #define TO_QUEUE_INIT(q) \ do { \ APR_RING_INIT(&(q).head, event_conn_state_t, timeout_list); \ (q).tag = #q; \ } while (0) #define TO_QUEUE_ELEM_INIT(el) APR_RING_ELEM_INIT(el, timeout_list) /* * The pollset for sockets that are in any of the timeout queues. Currently * we use the timeout_mutex to make sure that connections are added/removed * atomically to/from both event_pollset and a timeout queue. Otherwise * some confusion can happen under high load if timeout queues and pollset * get out of sync. * XXX: It should be possible to make the lock unnecessary in many or even all * XXX: cases. */ static apr_pollset_t *event_pollset; #if HAVE_SERF typedef struct { apr_pollset_t *pollset; apr_pool_t *pool; } s_baton_t; static serf_context_t *g_serf; #endif /* 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; typedef enum { PT_CSD, PT_ACCEPT #if HAVE_SERF , PT_SERF #endif } poll_type_e; typedef struct { poll_type_e type; void *baton; } listener_poll_type; /* data retained by event across load/unload of the module * allocated on first call to pre-config hook; located on * subsequent calls to pre-config hook */ typedef struct event_retained_data { int first_server_limit; int first_thread_limit; int module_loads; int sick_child_detected; ap_generation_t my_generation; int volatile is_graceful; /* set from signal handler */ int maxclients_reported; /* * The max child slot ever assigned, preserved across restarts. Necessary * to deal with MaxRequestWorkers changes across AP_SIG_GRACEFUL restarts. * We use this value to optimize routines that have to scan the entire * scoreboard. */ int max_daemons_limit; /* * 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. */ int idle_spawn_rate; #ifndef MAX_SPAWN_RATE #define MAX_SPAWN_RATE (32) #endif int hold_off_on_exponential_spawning; } event_retained_data; static event_retained_data *retained; #define ID_FROM_CHILD_THREAD(c, t) ((c * thread_limit) + t) static ap_pod_t *pod; /* The eventopt 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; /* 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 ap_equeue_t **worker_equeues; static void disable_listensocks(int process_slot) { int i; for (i = 0; i < num_listensocks; i++) { apr_pollset_remove(event_pollset, &listener_pollfd[i]); } ap_scoreboard_image->parent[process_slot].not_accepting = 1; } static void enable_listensocks(int process_slot) { int i; ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, APLOGNO(00457) "Accepting new connections again: " "%u active conns, %u idle workers", apr_atomic_read32(&connection_count), ap_queue_info_get_idlers(worker_queue_info)); for (i = 0; i < num_listensocks; i++) apr_pollset_add(event_pollset, &listener_pollfd[i]); /* * XXX: This is not yet optimal. If many workers suddenly become available, * XXX: the parent may kill some processes off too soon. */ ap_scoreboard_image->parent[process_slot].not_accepting = 0; } static void close_worker_sockets(void) { int i; for (i = 0; i < 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; } /* unblock the listener if it's waiting for a worker */ ap_queue_info_term(worker_queue_info); /* * 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); close_worker_sockets(); /* forcefully kill all current connections */ } } static int event_query(int query_code, int *result, apr_status_t *rv) { *rv = APR_SUCCESS; switch (query_code) { case AP_MPMQ_MAX_DAEMON_USED: *result = retained->max_daemons_limit; break; case AP_MPMQ_IS_THREADED: *result = AP_MPMQ_STATIC; break; case AP_MPMQ_IS_FORKED: *result = AP_MPMQ_DYNAMIC; break; case AP_MPMQ_IS_ASYNC: *result = 1; break; case AP_MPMQ_HAS_SERF: *result = 1; break; case AP_MPMQ_HARD_LIMIT_DAEMONS: *result = server_limit; break; case AP_MPMQ_HARD_LIMIT_THREADS: *result = thread_limit; break; case AP_MPMQ_MAX_THREADS: *result = threads_per_child; break; case AP_MPMQ_MIN_SPARE_DAEMONS: *result = 0; break; case AP_MPMQ_MIN_SPARE_THREADS: *result = min_spare_threads; break; case AP_MPMQ_MAX_SPARE_DAEMONS: *result = 0; break; case AP_MPMQ_MAX_SPARE_THREADS: *result = max_spare_threads; break; case AP_MPMQ_MAX_REQUESTS_DAEMON: *result = ap_max_requests_per_child; break; case AP_MPMQ_MAX_DAEMONS: *result = ap_daemons_limit; break; case AP_MPMQ_MPM_STATE: *result = mpm_state; break; case AP_MPMQ_GENERATION: *result = retained->my_generation; break; default: *rv = APR_ENOTIMPL; break; } return OK; } static void event_note_child_killed(int childnum, pid_t pid, ap_generation_t gen) { if (childnum != -1) { /* child had a scoreboard slot? */ ap_run_child_status(ap_server_conf, ap_scoreboard_image->parent[childnum].pid, ap_scoreboard_image->parent[childnum].generation, childnum, MPM_CHILD_EXITED); ap_scoreboard_image->parent[childnum].pid = 0; } else { ap_run_child_status(ap_server_conf, pid, gen, -1, MPM_CHILD_EXITED); } } static void event_note_child_started(int slot, pid_t pid) { ap_scoreboard_image->parent[slot].pid = pid; ap_run_child_status(ap_server_conf, ap_scoreboard_image->parent[slot].pid, retained->my_generation, slot, MPM_CHILD_STARTED); } static void event_note_child_lost_slot(int slot, pid_t newpid) { ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, APLOGNO(00458) "pid %" APR_PID_T_FMT " taking over scoreboard slot from " "%" APR_PID_T_FMT "%s", newpid, ap_scoreboard_image->parent[slot].pid, ap_scoreboard_image->parent[slot].quiescing ? " (quiescing)" : ""); ap_run_child_status(ap_server_conf, ap_scoreboard_image->parent[slot].pid, ap_scoreboard_image->parent[slot].generation, slot, MPM_CHILD_LOST_SLOT); /* Don't forget about this exiting child process, or we * won't be able to kill it if it doesn't exit by the * time the server is shut down. */ ap_register_extra_mpm_process(ap_scoreboard_image->parent[slot].pid, ap_scoreboard_image->parent[slot].generation); } static const char *event_get_name(void) { return "eventopt"; } /* 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); } if (one_process) { event_note_child_killed(/* slot */ 0, 0, 0); } exit(code); } static void just_die(int sig) { clean_child_exit(0); } /***************************************************************** * Connection structures and accounting... */ static int child_fatal; /* volatile because they're updated from a signal handler */ static int volatile shutdown_pending; static int volatile restart_pending; static apr_status_t decrement_connection_count(void *dummy) { apr_atomic_dec32(&connection_count); return APR_SUCCESS; } /* * 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(int graceful) { 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; retained->is_graceful = graceful; } /* 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; retained->is_graceful = graceful; } static void sig_term(int sig) { ap_start_shutdown(sig == AP_SIG_GRACEFUL_STOP); } 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, APLOGNO(00459) "sigaction(SIGTERM)"); #ifdef AP_SIG_GRACEFUL_STOP if (sigaction(AP_SIG_GRACEFUL_STOP, &sa, NULL) < 0) ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, APLOGNO(00460) "sigaction(" AP_SIG_GRACEFUL_STOP_STRING ")"); #endif #ifdef SIGINT if (sigaction(SIGINT, &sa, NULL) < 0) ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, APLOGNO(00461) "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, APLOGNO(00462) "sigaction(SIGXCPU)"); #endif #ifdef SIGXFSZ /* For systems following the LFS standard, ignoring SIGXFSZ allows * a write() beyond the 2GB limit to fail gracefully with E2BIG * rather than terminate the process. */ sa.sa_handler = SIG_IGN; if (sigaction(SIGXFSZ, &sa, NULL) < 0) ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, APLOGNO(00463) "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, APLOGNO(00464) "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, APLOGNO(00465) "sigaction(SIGHUP)"); if (sigaction(AP_SIG_GRACEFUL, &sa, NULL) < 0) ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, APLOGNO(00466) "sigaction(" AP_SIG_GRACEFUL_STRING ")"); #else if (!one_process) { #ifdef SIGXCPU apr_signal(SIGXCPU, SIG_DFL); #endif /* SIGXCPU */ #ifdef SIGXFSZ apr_signal(SIGXFSZ, SIG_IGN); #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 AP_SIG_GRACEFUL_STOP apr_signal(AP_SIG_GRACEFUL_STOP, sig_term); #endif /* AP_SIG_GRACEFUL_STOP */ #ifdef SIGPIPE apr_signal(SIGPIPE, SIG_IGN); #endif /* SIGPIPE */ #endif } static void process_pollop(pollset_op_t *op) { apr_status_t rv; event_conn_state_t *cs = op->cs; switch (op->timeout_type) { case TIMEOUT_WRITE_COMPLETION: TO_QUEUE_APPEND(write_completion_q, cs); break; case TIMEOUT_KEEPALIVE: TO_QUEUE_APPEND(keepalive_q, cs); break; case TIMEOUT_LINGER: TO_QUEUE_APPEND(linger_q, cs); break; case TIMEOUT_SHORT_LINGER: TO_QUEUE_APPEND(short_linger_q, cs); break; } rv = apr_pollset_add(event_pollset, &op->cs->pfd); if (rv != APR_SUCCESS && !APR_STATUS_IS_EEXIST(rv)) { ap_log_error(APLOG_MARK, APLOG_ERR, rv, ap_server_conf, APLOGNO(00467) "%s: apr_pollset_add failure", op->tag); } } /* * close our side of the connection * Pre-condition: cs is not in any timeout queue and not in the pollset, * timeout_mutex is not locked * return: 0 if connection is fully closed, * 1 if connection is lingering * may be called by listener or by worker thread. * the eq may be null if called from the listener thread, * and the pollset operations are done directly by this function. */ static int start_lingering_close(event_conn_state_t *cs, ap_equeue_t *eq) { apr_status_t rv; cs->c->sbh = NULL; /* prevent scoreboard updates from the listener * worker will loop around soon and set SERVER_READY */ if (ap_start_lingering_close(cs->c)) { apr_pool_clear(cs->p); ap_push_pool(worker_queue_info, cs->p); return 0; } else { apr_socket_t *csd = ap_get_conn_socket(cs->c); pollset_op_t localv; pollset_op_t *v; if (eq) { v = ap_equeue_writer_value(eq); } else { v = &localv; } #ifdef AP_DEBUG { rv = apr_socket_timeout_set(csd, 0); AP_DEBUG_ASSERT(rv == APR_SUCCESS); } #else apr_socket_timeout_set(csd, 0); #endif /* * If some module requested a shortened waiting period, only wait for * 2s (SECONDS_TO_LINGER). This is useful for mitigating certain * DoS attacks. */ if (apr_table_get(cs->c->notes, "short-lingering-close")) { cs->expiration_time = apr_time_now() + apr_time_from_sec(SECONDS_TO_LINGER); v->timeout_type = TIMEOUT_SHORT_LINGER; v->tag = "start_lingering_close(short)"; cs->pub.state = CONN_STATE_LINGER_SHORT; } else { cs->expiration_time = apr_time_now() + apr_time_from_sec(MAX_SECS_TO_LINGER); v->timeout_type = TIMEOUT_LINGER; v->tag = "start_lingering_close(normal)"; cs->pub.state = CONN_STATE_LINGER_NORMAL; } cs->pfd.reqevents = APR_POLLIN | APR_POLLHUP | APR_POLLERR; v->cs = cs; if (eq != NULL) { ap_equeue_writer_onward(eq); apr_pollset_wakeup(event_pollset); } else { process_pollop(v); } } return 1; } /* * forcibly close a lingering connection after the lingering period has * expired * Pre-condition: cs is not in any timeout queue and not in the pollset * return: irrelevant (need same prototype as start_lingering_close) */ static int stop_lingering_close(event_conn_state_t *cs, ap_equeue_t *eq) { apr_status_t rv; apr_socket_t *csd = ap_get_conn_socket(cs->c); ap_log_error(APLOG_MARK, APLOG_TRACE4, 0, ap_server_conf, "socket reached timeout in lingering-close state"); rv = apr_socket_close(csd); if (rv != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_ERR, rv, ap_server_conf, APLOGNO(00468) "error closing socket"); AP_DEBUG_ASSERT(0); } apr_pool_clear(cs->p); ap_push_pool(worker_queue_info, cs->p); return 0; } /* * process one connection in the worker * return: 1 if the connection has been completed, * 0 if it is still open and waiting for some event */ static int process_socket(apr_thread_t *thd, apr_pool_t * p, apr_socket_t * sock, event_conn_state_t * cs, ap_equeue_t *eq, int my_child_num, int my_thread_num) { conn_rec *c; long conn_id = ID_FROM_CHILD_THREAD(my_child_num, my_thread_num); int rc; ap_sb_handle_t *sbh; ap_create_sb_handle(&sbh, p, my_child_num, my_thread_num); if (cs == NULL) { /* This is a new connection */ listener_poll_type *pt = apr_pcalloc(p, sizeof(*pt)); cs = apr_pcalloc(p, sizeof(event_conn_state_t)); cs->bucket_alloc = apr_bucket_alloc_create(p); c = ap_run_create_connection(p, ap_server_conf, sock, conn_id, sbh, cs->bucket_alloc); if (!c) { apr_bucket_alloc_destroy(cs->bucket_alloc); apr_pool_clear(p); ap_push_pool(worker_queue_info, p); return 1; } apr_atomic_inc32(&connection_count); apr_pool_cleanup_register(c->pool, NULL, decrement_connection_count, apr_pool_cleanup_null); c->current_thread = thd; cs->c = c; c->cs = &(cs->pub); cs->p = p; cs->pfd.desc_type = APR_POLL_SOCKET; cs->pfd.reqevents = APR_POLLIN; cs->pfd.desc.s = sock; pt->type = PT_CSD; pt->baton = cs; cs->pfd.client_data = pt; ap_update_vhost_given_ip(c); rc = ap_run_pre_connection(c, sock); if (rc != OK && rc != DONE) { ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, c, APLOGNO(00469) "process_socket: connection aborted"); c->aborted = 1; } /** * XXX If the platform does not have a usable way of bundling * accept() with a socket readability check, like Win32, * and there are measurable delays before the * socket is readable due to the first data packet arriving, * it might be better to create the cs on the listener thread * with the state set to CONN_STATE_CHECK_REQUEST_LINE_READABLE * * FreeBSD users will want to enable the HTTP accept filter * module in their kernel for the highest performance * When the accept filter is active, sockets are kept in the * kernel until a HTTP request is received. */ cs->pub.state = CONN_STATE_READ_REQUEST_LINE; } else { c = cs->c; c->sbh = sbh; c->current_thread = thd; } if (c->clogging_input_filters && !c->aborted) { /* Since we have an input filter which 'cloggs' the input stream, * like mod_ssl, lets just do the normal read from input filters, * like the Worker MPM does. */ ap_run_process_connection(c); if (cs->pub.state != CONN_STATE_SUSPENDED) { cs->pub.state = CONN_STATE_LINGER; } } read_request: if (cs->pub.state == CONN_STATE_READ_REQUEST_LINE) { if (!c->aborted) { ap_run_process_connection(c); /* state will be updated upon return * fall thru to either wait for readability/timeout or * do lingering close */ } else { cs->pub.state = CONN_STATE_LINGER; } } if (cs->pub.state == CONN_STATE_WRITE_COMPLETION) { ap_filter_t *output_filter = c->output_filters; apr_status_t rv; ap_update_child_status_from_conn(sbh, SERVER_BUSY_WRITE, c); while (output_filter->next != NULL) { output_filter = output_filter->next; } rv = output_filter->frec->filter_func.out_func(output_filter, NULL); if (rv != APR_SUCCESS) { ap_log_cerror(APLOG_MARK, APLOG_DEBUG, rv, c, APLOGNO(00470) "network write failure in core output filter"); cs->pub.state = CONN_STATE_LINGER; } else if (c->data_in_output_filters) { /* Still in WRITE_COMPLETION_STATE: * Set a write timeout for this connection, and let the * event thread poll for writeability. */ pollset_op_t *v = ap_equeue_writer_value(eq); cs->expiration_time = ap_server_conf->timeout + apr_time_now(); cs->pfd.reqevents = APR_POLLOUT | APR_POLLHUP | APR_POLLERR; v->cs = cs; v->timeout_type = TIMEOUT_WRITE_COMPLETION; v->tag = "process_socket(write_completion)"; ap_equeue_writer_onward(eq); apr_pollset_wakeup(event_pollset); return 1; } else if (c->keepalive != AP_CONN_KEEPALIVE || c->aborted || listener_may_exit) { cs->pub.state = CONN_STATE_LINGER; } else if (c->data_in_input_filters) { cs->pub.state = CONN_STATE_READ_REQUEST_LINE; goto read_request; } else { cs->pub.state = CONN_STATE_CHECK_REQUEST_LINE_READABLE; } } if (cs->pub.state == CONN_STATE_LINGER) { if (!start_lingering_close(cs, eq)) { return 0; } } else if (cs->pub.state == CONN_STATE_CHECK_REQUEST_LINE_READABLE) { pollset_op_t *v; /* It greatly simplifies the logic to use a single timeout value here * because the new element can just be added to the end of the list and * it will stay sorted in expiration time sequence. If brand new * sockets are sent to the event thread for a readability check, this * will be a slight behavior change - they use the non-keepalive * timeout today. With a normal client, the socket will be readable in * a few milliseconds anyway. */ cs->expiration_time = ap_server_conf->keep_alive_timeout + apr_time_now(); /* Add work to pollset. */ v = ap_equeue_writer_value(eq); v->timeout_type = TIMEOUT_KEEPALIVE; v->cs = cs; cs->pfd.reqevents = APR_POLLIN; v->tag = "process_socket(keepalive)"; ap_equeue_writer_onward(eq); apr_pollset_wakeup(event_pollset); } return 1; } /* requests_this_child has gone to zero or below. See if the admin coded "MaxConnectionsPerChild 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 { requests_this_child = INT_MAX; /* keep going */ } } static void close_listeners(int process_slot, int *closed) { if (!*closed) { int i; disable_listensocks(process_slot); ap_close_listeners(); *closed = 1; dying = 1; ap_scoreboard_image->parent[process_slot].quiescing = 1; for (i = 0; i < threads_per_child; ++i) { ap_update_child_status_from_indexes(process_slot, i, SERVER_GRACEFUL, NULL); } /* wake up the main thread */ kill(ap_my_pid, SIGTERM); } } 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. */ } #if HAVE_SERF static apr_status_t s_socket_add(void *user_baton, apr_pollfd_t *pfd, void *serf_baton) { s_baton_t *s = (s_baton_t*)user_baton; /* XXXXX: recycle listener_poll_types */ listener_poll_type *pt = ap_malloc(sizeof(*pt)); pt->type = PT_SERF; pt->baton = serf_baton; pfd->client_data = pt; return apr_pollset_add(s->pollset, pfd); } static apr_status_t s_socket_remove(void *user_baton, apr_pollfd_t *pfd, void *serf_baton) { s_baton_t *s = (s_baton_t*)user_baton; listener_poll_type *pt = pfd->client_data; free(pt); return apr_pollset_remove(s->pollset, pfd); } #endif static apr_status_t init_pollset(apr_pool_t *p) { #if HAVE_SERF s_baton_t *baton = NULL; #endif ap_listen_rec *lr; listener_poll_type *pt; int i = 0; TO_QUEUE_INIT(write_completion_q); TO_QUEUE_INIT(keepalive_q); TO_QUEUE_INIT(linger_q); TO_QUEUE_INIT(short_linger_q); listener_pollfd = apr_palloc(p, sizeof(apr_pollfd_t) * num_listensocks); for (lr = ap_listeners; lr != NULL; lr = lr->next, i++) { apr_pollfd_t *pfd; AP_DEBUG_ASSERT(i < num_listensocks); pfd = &listener_pollfd[i]; pt = apr_pcalloc(p, sizeof(*pt)); pfd->desc_type = APR_POLL_SOCKET; pfd->desc.s = lr->sd; pfd->reqevents = APR_POLLIN; pt->type = PT_ACCEPT; pt->baton = lr; pfd->client_data = pt; apr_socket_opt_set(pfd->desc.s, APR_SO_NONBLOCK, 1); apr_pollset_add(event_pollset, pfd); lr->accept_func = ap_unixd_accept; } #if HAVE_SERF baton = apr_pcalloc(p, sizeof(*baton)); baton->pollset = event_pollset; /* TODO: subpools, threads, reuse, etc. -- currently use malloc() inside :( */ baton->pool = p; g_serf = serf_context_create_ex(baton, s_socket_add, s_socket_remove, p); ap_register_provider(p, "mpm_serf", "instance", "0", g_serf); #endif return APR_SUCCESS; } static apr_status_t push_timer2worker(timer_event_t* te) { return ap_queue_push_timer(worker_queue, te); } /* * Pre-condition: pfd->cs is neither in pollset nor timeout queue * this function may only be called by the listener */ static apr_status_t push2worker(const apr_pollfd_t * pfd, apr_pollset_t * pollset) { listener_poll_type *pt = (listener_poll_type *) pfd->client_data; event_conn_state_t *cs = (event_conn_state_t *) pt->baton; apr_status_t rc; rc = ap_queue_push(worker_queue, cs->pfd.desc.s, cs, cs->p); if (rc != APR_SUCCESS) { /* trash the connection; we couldn't queue the connected * socket to a worker */ apr_bucket_alloc_destroy(cs->bucket_alloc); apr_socket_close(cs->pfd.desc.s); ap_log_error(APLOG_MARK, APLOG_CRIT, rc, ap_server_conf, APLOGNO(00471) "push2worker: ap_queue_push failed"); apr_pool_clear(cs->p); ap_push_pool(worker_queue_info, cs->p); } return rc; } /* get_worker: * If *have_idle_worker_p == 0, reserve a worker thread, and set * *have_idle_worker_p = 1. * If *have_idle_worker_p is already 1, will do nothing. * If blocking == 1, block if all workers are currently busy. * If no worker was available immediately, will set *all_busy to 1. * XXX: If there are no workers, we should not block immediately but * XXX: close all keep-alive connections first. */ static void get_worker(int *have_idle_worker_p, int blocking, int *all_busy) { apr_status_t rc; if (*have_idle_worker_p) { /* already reserved a worker thread - must have hit a * transient error on a previous pass */ return; } if (blocking) rc = ap_queue_info_wait_for_idler(worker_queue_info, all_busy); else rc = ap_queue_info_try_get_idler(worker_queue_info); if (rc == APR_SUCCESS) { *have_idle_worker_p = 1; } else if (!blocking && rc == APR_EAGAIN) { *all_busy = 1; } else if (!APR_STATUS_IS_EOF(rc)) { ap_log_error(APLOG_MARK, APLOG_ERR, rc, ap_server_conf, APLOGNO(00472) "ap_queue_info_wait_for_idler failed. " "Attempting to shutdown process gracefully"); signal_threads(ST_GRACEFUL); } } /* XXXXXX: Convert to skiplist or other better data structure * (yes, this is VERY VERY VERY VERY BAD) */ /* Structures to reuse */ static APR_RING_HEAD(timer_free_ring_t, timer_event_t) timer_free_ring; /* Active timers */ static APR_RING_HEAD(timer_ring_t, timer_event_t) timer_ring; static apr_thread_mutex_t *g_timer_ring_mtx; static apr_status_t event_register_timed_callback(apr_time_t t, ap_mpm_callback_fn_t *cbfn, void *baton) { int inserted = 0; timer_event_t *ep; timer_event_t *te; /* oh yeah, and make locking smarter/fine grained. */ apr_thread_mutex_lock(g_timer_ring_mtx); if (!APR_RING_EMPTY(&timer_free_ring, timer_event_t, link)) { te = APR_RING_FIRST(&timer_free_ring); APR_RING_REMOVE(te, link); } else { /* XXXXX: lol, pool allocation without a context from any thread.Yeah. Right. MPMs Suck. */ te = ap_malloc(sizeof(timer_event_t)); APR_RING_ELEM_INIT(te, link); } te->cbfunc = cbfn; te->baton = baton; /* XXXXX: optimize */ te->when = t + apr_time_now(); /* Okay, insert sorted by when.. */ for (ep = APR_RING_FIRST(&timer_ring); ep != APR_RING_SENTINEL(&timer_ring, timer_event_t, link); ep = APR_RING_NEXT(ep, link)) { if (ep->when > te->when) { inserted = 1; APR_RING_INSERT_BEFORE(ep, te, link); break; } } if (!inserted) { APR_RING_INSERT_TAIL(&timer_ring, te, timer_event_t, link); } apr_thread_mutex_unlock(g_timer_ring_mtx); return APR_SUCCESS; } /* * Close socket and clean up if remote closed its end while we were in * lingering close. * Only to be called in the listener thread; * Pre-condition: cs is in one of the linger queues and in the pollset */ static void process_lingering_close(event_conn_state_t *cs, const apr_pollfd_t *pfd) { apr_socket_t *csd = ap_get_conn_socket(cs->c); char dummybuf[2048]; apr_size_t nbytes; apr_status_t rv; struct timeout_queue *q; q = (cs->pub.state == CONN_STATE_LINGER_SHORT) ? &short_linger_q : &linger_q; /* socket is already in non-blocking state */ do { nbytes = sizeof(dummybuf); rv = apr_socket_recv(csd, dummybuf, &nbytes); } while (rv == APR_SUCCESS); if (!APR_STATUS_IS_EOF(rv)) { return; } rv = apr_pollset_remove(event_pollset, pfd); AP_DEBUG_ASSERT(rv == APR_SUCCESS); rv = apr_socket_close(csd); AP_DEBUG_ASSERT(rv == APR_SUCCESS); TO_QUEUE_REMOVE(*q, cs); TO_QUEUE_ELEM_INIT(cs); apr_pool_clear(cs->p); ap_push_pool(worker_queue_info, cs->p); } /* call 'func' for all elements of 'q' with timeout less than 'timeout_time'. * Pre-condition: timeout_mutex must already be locked * Post-condition: timeout_mutex will be locked again */ static void process_timeout_queue(struct timeout_queue *q, apr_time_t timeout_time, int (*func)(event_conn_state_t *, ap_equeue_t *eq)) { int count = 0; event_conn_state_t *first, *cs, *last; apr_status_t rv; if (!q->count) { return; } AP_DEBUG_ASSERT(!APR_RING_EMPTY(&q->head, event_conn_state_t, timeout_list)); cs = first = APR_RING_FIRST(&q->head); while (cs != APR_RING_SENTINEL(&q->head, event_conn_state_t, timeout_list) && cs->expiration_time < timeout_time) { last = cs; rv = apr_pollset_remove(event_pollset, &cs->pfd); if (rv != APR_SUCCESS && !APR_STATUS_IS_NOTFOUND(rv)) { ap_log_cerror(APLOG_MARK, APLOG_ERR, rv, cs->c, APLOGNO(00473) "apr_pollset_remove failed"); } cs = APR_RING_NEXT(cs, timeout_list); count++; } if (!count) return; APR_RING_UNSPLICE(first, last, timeout_list); AP_DEBUG_ASSERT(q->count >= count); q->count -= count; while (count) { cs = APR_RING_NEXT(first, timeout_list); TO_QUEUE_ELEM_INIT(first); func(first, NULL); first = cs; count--; } } static void * APR_THREAD_FUNC listener_thread(apr_thread_t * thd, void *dummy) { timer_event_t *ep; timer_event_t *te; apr_status_t rc; 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 */ ap_listen_rec *lr; int have_idle_worker = 0; event_conn_state_t *cs; const apr_pollfd_t *out_pfd; apr_int32_t num = 0; apr_interval_time_t timeout_interval; apr_time_t timeout_time = 0, now, last_log; listener_poll_type *pt; int closed = 0, listeners_disabled = 0; last_log = apr_time_now(); free(ti); /* the following times out events that are really close in the future * to prevent extra poll calls * * current value is .1 second */ #define TIMEOUT_FUDGE_FACTOR 100000 #define EVENT_FUDGE_FACTOR 10000 rc = init_pollset(tpool); if (rc != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_ERR, rc, ap_server_conf, "failed to initialize pollset, " "attempting to shutdown process gracefully"); signal_threads(ST_GRACEFUL); return NULL; } /* 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); for (;;) { int workers_were_busy = 0; if (listener_may_exit) { close_listeners(process_slot, &closed); if (terminate_mode == ST_UNGRACEFUL || apr_atomic_read32(&connection_count) == 0) break; } if (requests_this_child <= 0) { check_infinite_requests(); } now = apr_time_now(); if (APLOGtrace6(ap_server_conf)) { /* trace log status every second */ if (now - last_log > apr_time_from_msec(1000)) { last_log = now; ap_log_error(APLOG_MARK, APLOG_TRACE6, 0, ap_server_conf, "connections: %d (write-completion: %d " "keep-alive: %d lingering: %d)", connection_count, write_completion_q.count, keepalive_q.count, linger_q.count + short_linger_q.count); } } apr_thread_mutex_lock(g_timer_ring_mtx); if (!APR_RING_EMPTY(&timer_ring, timer_event_t, link)) { te = APR_RING_FIRST(&timer_ring); if (te->when > now) { timeout_interval = te->when - now; } else { timeout_interval = 1; } } else { timeout_interval = apr_time_from_msec(100); } apr_thread_mutex_unlock(g_timer_ring_mtx); #if HAVE_SERF rc = serf_context_prerun(g_serf); if (rc != APR_SUCCESS) { /* TOOD: what should do here? ugh. */ } #endif rc = apr_pollset_poll(event_pollset, timeout_interval, &num, &out_pfd); if (rc != APR_SUCCESS && !APR_STATUS_IS_EINTR(rc) && !APR_STATUS_IS_TIMEUP(rc)) { ap_log_error(APLOG_MARK, APLOG_CRIT, rc, ap_server_conf, "apr_pollset_poll failed. Attempting to " "shutdown process gracefully"); signal_threads(ST_GRACEFUL); } if (listener_may_exit) { close_listeners(process_slot, &closed); if (terminate_mode == ST_UNGRACEFUL || apr_atomic_read32(&connection_count) == 0) break; } now = apr_time_now(); apr_thread_mutex_lock(g_timer_ring_mtx); for (ep = APR_RING_FIRST(&timer_ring); ep != APR_RING_SENTINEL(&timer_ring, timer_event_t, link); ep = APR_RING_FIRST(&timer_ring)) { if (ep->when < now + EVENT_FUDGE_FACTOR) { APR_RING_REMOVE(ep, link); push_timer2worker(ep); } else { break; } } apr_thread_mutex_unlock(g_timer_ring_mtx); while (num) { pt = (listener_poll_type *) out_pfd->client_data; if (pt->type == PT_CSD) { /* one of the sockets is readable */ struct timeout_queue *remove_from_q = &write_completion_q; int blocking = 1; cs = (event_conn_state_t *)pt->baton; switch (cs->pub.state) { case CONN_STATE_CHECK_REQUEST_LINE_READABLE: cs->pub.state = CONN_STATE_READ_REQUEST_LINE; remove_from_q = &keepalive_q; /* don't wait for a worker for a keepalive request */ blocking = 0; /* FALL THROUGH */ case CONN_STATE_WRITE_COMPLETION: get_worker(&have_idle_worker, blocking, &workers_were_busy); TO_QUEUE_REMOVE(*remove_from_q, cs); rc = apr_pollset_remove(event_pollset, &cs->pfd); /* * Some of the pollset backends, like KQueue or Epoll * automagically remove the FD if the socket is closed, * therefore, we can accept _SUCCESS or _NOTFOUND, * and we still want to keep going */ if (rc != APR_SUCCESS && !APR_STATUS_IS_NOTFOUND(rc)) { ap_log_error(APLOG_MARK, APLOG_ERR, rc, ap_server_conf, "pollset remove failed"); start_lingering_close(cs, NULL); break; } TO_QUEUE_ELEM_INIT(cs); /* If we didn't get a worker immediately for a keep-alive * request, we close the connection, so that the client can * re-connect to a different process. */ if (!have_idle_worker) { start_lingering_close(cs, NULL); break; } rc = push2worker(out_pfd, event_pollset); if (rc != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_CRIT, rc, ap_server_conf, "push2worker failed"); } else { have_idle_worker = 0; } break; case CONN_STATE_LINGER_NORMAL: case CONN_STATE_LINGER_SHORT: process_lingering_close(cs, out_pfd); break; default: ap_log_error(APLOG_MARK, APLOG_CRIT, rc, ap_server_conf, "event_loop: unexpected state %d", cs->pub.state); ap_assert(0); } } else if (pt->type == PT_ACCEPT) { int skip_accept = 0; int connection_count_local = connection_count; /* A Listener Socket is ready for an accept() */ if (workers_were_busy) { skip_accept = 1; ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, "All workers busy, not accepting new conns" "in this process"); } else if (listeners_disabled) { listeners_disabled = 0; enable_listensocks(process_slot); } else if (connection_count_local > threads_per_child + ap_queue_info_get_idlers(worker_queue_info) * worker_factor / WORKER_FACTOR_SCALE) { skip_accept = 1; ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, "Too many open connections (%u), " "not accepting new conns in this process", connection_count_local); ap_log_error(APLOG_MARK, APLOG_TRACE1, 0, ap_server_conf, "Idle workers: %u", ap_queue_info_get_idlers(worker_queue_info)); } if (skip_accept == 0) { lr = (ap_listen_rec *) pt->baton; ap_pop_pool(&ptrans, worker_queue_info); if (ptrans == NULL) { /* create a new transaction pool for each accepted socket */ apr_allocator_t *allocator; apr_allocator_create(&allocator); apr_allocator_max_free_set(allocator, ap_max_mem_free); apr_pool_create_ex(&ptrans, pconf, NULL, allocator); apr_allocator_owner_set(allocator, ptrans); if (ptrans == NULL) { ap_log_error(APLOG_MARK, APLOG_CRIT, rc, ap_server_conf, "Failed to create transaction pool"); signal_threads(ST_GRACEFUL); return NULL; } } apr_pool_tag(ptrans, "transaction"); get_worker(&have_idle_worker, 1, &workers_were_busy); rc = lr->accept_func(&csd, lr, ptrans); /* later we trash rv and rely on csd to indicate * success/failure */ AP_DEBUG_ASSERT(rc == APR_SUCCESS || !csd); if (rc == APR_EGENERAL) { /* E[NM]FILE, ENOMEM, etc */ resource_shortage = 1; signal_threads(ST_GRACEFUL); } if (csd != NULL) { rc = ap_queue_push(worker_queue, csd, NULL, ptrans); if (rc != APR_SUCCESS) { /* trash the connection; we couldn't queue the connected * socket to a worker */ apr_socket_close(csd); ap_log_error(APLOG_MARK, APLOG_CRIT, rc, ap_server_conf, "ap_queue_push failed"); apr_pool_clear(ptrans); ap_push_pool(worker_queue_info, ptrans); } else { have_idle_worker = 0; } } else { apr_pool_clear(ptrans); ap_push_pool(worker_queue_info, ptrans); } } } /* if:else on pt->type */ #if HAVE_SERF else if (pt->type == PT_SERF) { /* send socket to serf. */ /* XXXX: this doesn't require get_worker() */ serf_event_trigger(g_serf, pt->baton, out_pfd); } #endif out_pfd++; num--; } /* while for processing poll */ { /* TODO: break out to separate function */ int i; for (i = 0; i < threads_per_child; i++) { ap_equeue_t *eq = worker_equeues[i]; pollset_op_t *op = NULL; while ((op = ap_equeue_reader_next(eq)) != NULL) { process_pollop(op); } } } /* XXX possible optimization: stash the current time for use as * r->request_time for new requests */ now = apr_time_now(); /* we only do this once per 0.1s (TIMEOUT_FUDGE_FACTOR) */ if (now > timeout_time) { struct process_score *ps; timeout_time = now + TIMEOUT_FUDGE_FACTOR; /* handle timed out sockets */ /* Step 1: keepalive timeouts */ /* If all workers are busy, we kill older keep-alive connections so that they * may connect to another process. */ if (workers_were_busy && keepalive_q.count) { ap_log_error(APLOG_MARK, APLOG_TRACE1, 0, ap_server_conf, "All workers are busy, will close %d keep-alive " "connections", keepalive_q.count); process_timeout_queue(&keepalive_q, timeout_time + ap_server_conf->keep_alive_timeout, start_lingering_close); } else { process_timeout_queue(&keepalive_q, timeout_time, start_lingering_close); } /* Step 2: write completion timeouts */ process_timeout_queue(&write_completion_q, timeout_time, start_lingering_close); /* Step 3: (normal) lingering close completion timeouts */ process_timeout_queue(&linger_q, timeout_time, stop_lingering_close); /* Step 4: (short) lingering close completion timeouts */ process_timeout_queue(&short_linger_q, timeout_time, stop_lingering_close); ps = ap_get_scoreboard_process(process_slot); ps->write_completion = write_completion_q.count; ps->lingering_close = linger_q.count + short_linger_q.count; ps->keep_alive = keepalive_q.count; ps->connections = apr_atomic_read32(&connection_count); /* XXX: should count CONN_STATE_SUSPENDED and set ps->suspended */ } if (listeners_disabled && !workers_were_busy && (int)apr_atomic_read32(&connection_count) < ((int)ap_queue_info_get_idlers(worker_queue_info) - 1) * worker_factor / WORKER_FACTOR_SCALE + threads_per_child) { listeners_disabled = 0; enable_listensocks(process_slot); } /* * XXX: do we need to set some timeout that re-enables the listensocks * XXX: in case no other event occurs? */ } /* listener main loop */ close_listeners(process_slot, &closed); ap_queue_term(worker_queue); 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; event_conn_state_t *cs; apr_pool_t *ptrans; /* Pool for per-transaction stuff */ apr_status_t rv; int is_idle = 0; timer_event_t *te = NULL; ap_equeue_t *eq = worker_equeues[thread_slot]; free(ti); ap_scoreboard_image->servers[process_slot][thread_slot].pid = ap_my_pid; ap_scoreboard_image->servers[process_slot][thread_slot].tid = apr_os_thread_current(); ap_scoreboard_image->servers[process_slot][thread_slot].generation = retained->my_generation; 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, 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, dying ? SERVER_GRACEFUL : SERVER_READY, NULL); worker_pop: if (workers_may_exit) { break; } te = NULL; rv = ap_queue_pop_something(worker_queue, &csd, &cs, &ptrans, &te); 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; } if (te != NULL) { te->cbfunc(te->baton); { apr_thread_mutex_lock(g_timer_ring_mtx); APR_RING_INSERT_TAIL(&timer_free_ring, te, timer_event_t, link); apr_thread_mutex_unlock(g_timer_ring_mtx); } } else { is_idle = 0; worker_sockets[thread_slot] = csd; rv = process_socket(thd, ptrans, csd, cs, eq, process_slot, thread_slot); if (!rv) { requests_this_child--; } worker_sockets[thread_slot] = NULL; } } 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 *) ap_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, APLOGNO(00474) "apr_thread_create: unable to create listener thread"); /* let the parent decide how bad this really is */ clean_child_exit(APEXIT_CHILDSICK); } 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; int max_recycled_pools = -1; int good_methods[] = {APR_POLLSET_KQUEUE, APR_POLLSET_PORT, APR_POLLSET_EPOLL}; /* 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, 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); } if (ap_max_mem_free != APR_ALLOCATOR_MAX_FREE_UNLIMITED) { /* If we want to conserve memory, let's not keep an unlimited number of * pools & allocators. * XXX: This should probably be a separate config directive */ max_recycled_pools = threads_per_child * 3 / 4 ; } rv = ap_queue_info_create(&worker_queue_info, pchild, threads_per_child, max_recycled_pools); 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); } /* Create the main pollset */ for (i = 0; i < sizeof(good_methods) / sizeof(void*); i++) { rv = apr_pollset_create_ex(&event_pollset, threads_per_child*2, /* XXX don't we need more, to handle * connections in K-A or lingering * close? */ pchild, APR_POLLSET_WAKEABLE|APR_POLLSET_NOCOPY|APR_POLLSET_NODEFAULT, good_methods[i]); if (rv == APR_SUCCESS) { break; } } if (rv != APR_SUCCESS) { rv = apr_pollset_create(&event_pollset, threads_per_child*2, /* XXX don't we need more, to handle * connections in K-A or lingering * close? */ pchild, APR_POLLSET_WAKEABLE|APR_POLLSET_NOCOPY); } if (rv != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_ERR, rv, ap_server_conf, "apr_pollset_create failed; check system or user limits"); clean_child_exit(APEXIT_CHILDFATAL); } ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, APLOGNO() "start_threads: Using %s", apr_pollset_method_name(event_pollset)); worker_sockets = apr_pcalloc(pchild, threads_per_child * sizeof(apr_socket_t *)); worker_equeues = apr_palloc(pchild, threads_per_child * sizeof(ap_equeue_t*)); for (i = 0; i < threads_per_child; i++) { ap_equeue_t* eq = NULL; /* TODO: research/test optimal size of queue here */ ap_equeue_create(pchild, 16, sizeof(pollset_op_t), &eq); /* same as thread ID */ worker_equeues[i] = eq; } loops = prev_threads_created = 0; while (1) { /* threads_per_child does not include the listener thread */ for (i = 0; i < 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 *) ap_malloc(sizeof(proc_info)); 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"); /* let the parent decide how bad this really is */ clean_child_exit(APEXIT_CHILDSICK); } 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 == 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, 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 && !dying) { /* listener has not stopped accepting 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, APLOGNO(00475) "the listener thread didn't stop accepting"); } else { rv = apr_thread_join(&thread_rv, listener); if (rv != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ap_server_conf, APLOGNO(00476) "apr_thread_join: unable to join listener thread"); } } } for (i = 0; i < 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, APLOGNO(00477) "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, APLOGNO(00478) "apr_thread_join: unable to join the start " "thread"); } } static void force_set_tz(apr_pool_t *p) { /* If the TZ variable is unset, many operationg systems, * such as Linux, will at runtime read from /etc/localtime * and call fstat on it. * * By forcing the time zone to UTC if it is unset, we gain * about 2% in raw requests/second (since we format log files * in the local time, if present) * * For more info, see: * */ char *v = NULL; apr_status_t rv; rv = apr_env_get(&v, "TZ", p); if (v == NULL || rv == APR_ENOENT) { apr_env_set("TZ", "UTC+0", p); } } 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); if (ap_run_drop_privileges(pchild, ap_server_conf)) { clean_child_exit(APEXIT_CHILDFATAL); } apr_thread_mutex_create(&g_timer_ring_mtx, APR_THREAD_MUTEX_DEFAULT, pchild); APR_RING_INIT(&timer_free_ring, timer_event_t, link); APR_RING_INIT(&timer_ring, timer_event_t, link); 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, APLOGNO(00479) "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 = ap_calloc(threads_per_child, sizeof(apr_thread_t *)); ts = 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, APLOGNO(00480) "apr_thread_create: unable to create worker thread"); /* let the parent decide how bad this really is */ clean_child_exit(APEXIT_CHILDSICK); } 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); /* helps us terminate a little more quickly than the dispatch of the * signal thread; beats the Pipe of Death and the browsers */ signal_threads(ST_UNGRACEFUL); /* 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 MaxConnectionsPerChild) 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_podx_check(pod); if (rv == AP_MPM_PODX_NORESTART) { /* see if termination was triggered while we slept */ switch (terminate_mode) { case ST_GRACEFUL: rv = AP_MPM_PODX_GRACEFUL; break; case ST_UNGRACEFUL: rv = AP_MPM_PODX_RESTART; break; } } if (rv == AP_MPM_PODX_GRACEFUL || rv == AP_MPM_PODX_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_MPM_PODX_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 > retained->max_daemons_limit) { retained->max_daemons_limit = slot + 1; } if (one_process) { set_signals(); event_note_child_started(slot, getpid()); child_main(slot); /* NOTREACHED */ } if ((pid = fork()) == -1) { ap_log_error(APLOG_MARK, APLOG_ERR, errno, s, APLOGNO(00481) "fork: Unable to fork new process"); /* fork didn't succeed. There's no need to touch the scoreboard; * if we were trying to replace a failed child process, then * server_main_loop() marked its workers SERVER_DEAD, and if * we were trying to replace a child process that exited normally, * its worker_thread()s left SERVER_DEAD or SERVER_GRACEFUL behind. */ /* 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_DEBUG, errno, ap_server_conf, APLOGNO(00482) "processor unbind failed"); #endif RAISE_SIGSTOP(MAKE_CHILD); apr_signal(SIGTERM, just_die); child_main(slot); /* NOTREACHED */ } /* else */ if (ap_scoreboard_image->parent[slot].pid != 0) { /* This new child process is squatting on the scoreboard * entry owned by an exiting child process, which cannot * exit until all active requests complete. */ event_note_child_lost_slot(slot, pid); } ap_scoreboard_image->parent[slot].quiescing = 0; ap_scoreboard_image->parent[slot].not_accepting = 0; event_note_child_started(slot, 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; } } 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; int active_thread_count = 0; /* 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 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 >= retained->max_daemons_limit && totally_free_length == retained->idle_spawn_rate) /* short cut if all active processes have been examined and * enough empty scoreboard slots have been found */ break; ps = &ap_scoreboard_image->parent[i]; for (j = 0; j < 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 (ps->pid != 0) { /* XXX just set all_dead_threads in outer for loop if no pid? not much else matters */ if (status <= SERVER_READY && !ps->quiescing && !ps->not_accepting && ps->generation == retained->my_generation) { ++idle_thread_count; } if (status >= SERVER_READY && status < SERVER_GRACEFUL) { ++active_thread_count; } } } if (any_dead_threads && totally_free_length < retained->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; } } if (retained->sick_child_detected) { if (active_thread_count > 0) { /* some child processes appear to be working. don't kill the * whole server. */ retained->sick_child_detected = 0; } else { /* looks like a basket case. give up. */ shutdown_pending = 1; child_fatal = 1; ap_log_error(APLOG_MARK, APLOG_ALERT, 0, ap_server_conf, APLOGNO(00483) "No active workers found..." " Apache is exiting!"); /* the child already logged the failure details */ return; } } retained->max_daemons_limit = last_non_dead + 1; if (idle_thread_count > max_spare_threads) { /* Kill off one child */ ap_mpm_podx_signal(pod, AP_MPM_PODX_GRACEFUL); retained->idle_spawn_rate = 1; } else if (idle_thread_count < min_spare_threads) { /* terminate the free list */ if (free_length == 0) { /* scoreboard is full, can't fork */ if (active_thread_count >= ap_daemons_limit * threads_per_child) { if (!retained->maxclients_reported) { /* only report this condition once */ ap_log_error(APLOG_MARK, APLOG_ERR, 0, ap_server_conf, APLOGNO(00484) "server reached MaxRequestWorkers setting, " "consider raising the MaxRequestWorkers " "setting"); retained->maxclients_reported = 1; } } else { ap_log_error(APLOG_MARK, APLOG_ERR, 0, ap_server_conf, APLOGNO(00485) "scoreboard is full, not at MaxRequestWorkers"); } retained->idle_spawn_rate = 1; } else { if (free_length > retained->idle_spawn_rate) { free_length = retained->idle_spawn_rate; } if (retained->idle_spawn_rate >= 8) { ap_log_error(APLOG_MARK, APLOG_INFO, 0, ap_server_conf, APLOGNO(00486) "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 (retained->hold_off_on_exponential_spawning) { --retained->hold_off_on_exponential_spawning; } else if (retained->idle_spawn_rate < MAX_SPAWN_RATE) { retained->idle_spawn_rate *= 2; } } } else { retained->idle_spawn_rate = 1; } } static void server_main_loop(int remaining_children_to_start) { ap_generation_t old_gen; 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, ap_server_conf); if (pid.pid != -1) { processed_status = ap_process_child_status(&pid, exitwhy, status); child_slot = ap_find_child_by_pid(&pid); if (processed_status == APEXIT_CHILDFATAL) { /* fix race condition found in PR 39311 * A child created at the same time as a graceful happens * can find the lock missing and create a fatal error. * It is not fatal for the last generation to be in this state. */ if (child_slot < 0 || ap_get_scoreboard_process(child_slot)->generation == retained->my_generation) { shutdown_pending = 1; child_fatal = 1; return; } else { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, ap_server_conf, APLOGNO(00487) "Ignoring fatal error in child of previous " "generation (pid %ld).", (long)pid.pid); retained->sick_child_detected = 1; } } else if (processed_status == APEXIT_CHILDSICK) { /* tell perform_idle_server_maintenance to check into this * on the next timer pop */ retained->sick_child_detected = 1; } /* non-fatal death... note that it's gone in the scoreboard. */ if (child_slot >= 0) { for (i = 0; i < threads_per_child; i++) ap_update_child_status_from_indexes(child_slot, i, SERVER_DEAD, (request_rec *) NULL); event_note_child_killed(child_slot, 0, 0); ap_scoreboard_image->parent[child_slot].quiescing = 0; if (processed_status == APEXIT_CHILDSICK) { /* resource shortage, minimize the fork rate */ retained->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; } } else if (ap_unregister_extra_mpm_process(pid.pid, &old_gen) == 1) { event_note_child_killed(-1, /* already out of the scoreboard */ pid.pid, old_gen); #if APR_HAS_OTHER_CHILD } else if (apr_proc_other_child_alert(&pid, APR_OC_REASON_DEATH, status) == 0) { /* handled */ #endif } else if (retained->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, APLOGNO(00488) "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(); } } static int event_run(apr_pool_t * _pconf, apr_pool_t * plog, server_rec * s) { int remaining_children_to_start; ap_log_pid(pconf, ap_pid_fname); if (!retained->is_graceful) { if (ap_run_pre_mpm(s->process->pool, SB_SHARED) != OK) { mpm_state = AP_MPMQ_STOPPING; return DONE; } /* fix the generation number in the global score; we just got a new, * cleared scoreboard */ ap_scoreboard_image->global->running_generation = retained->my_generation; } restart_pending = shutdown_pending = 0; set_signals(); /* Don't thrash... */ if (max_spare_threads < min_spare_threads + threads_per_child) max_spare_threads = min_spare_threads + 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 may start a new one, until * there are at least min_spare_threads idle threads, counting across * all children. But we may be permitted to start more children 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 (!retained->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 */ retained->hold_off_on_exponential_spawning = 10; } ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf, APLOGNO(00489) "%s configured -- resuming normal operations", ap_get_server_description()); ap_log_error(APLOG_MARK, APLOG_INFO, 0, ap_server_conf, APLOGNO(00490) "Server built: %s", ap_get_server_built()); ap_log_command_line(plog, s); mpm_state = AP_MPMQ_RUNNING; server_main_loop(remaining_children_to_start); mpm_state = AP_MPMQ_STOPPING; if (shutdown_pending && !retained->is_graceful) { /* Time to shut down: * Kill child processes, tell them to call child_exit, etc... */ ap_mpm_podx_killpg(pod, ap_daemons_limit, AP_MPM_PODX_RESTART); ap_reclaim_child_processes(1, /* Start with SIGTERM */ event_note_child_killed); if (!child_fatal) { /* cleanup pid file on normal shutdown */ ap_remove_pid(pconf, ap_pid_fname); ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf, APLOGNO(00491) "caught SIGTERM, shutting down"); } return DONE; } else if (shutdown_pending) { /* Time to gracefully shut down: * Kill child processes, tell them to call child_exit, etc... */ int active_children; int index; apr_time_t cutoff = 0; /* Close our listeners, and then ask our children to do same */ ap_close_listeners(); ap_mpm_podx_killpg(pod, ap_daemons_limit, AP_MPM_PODX_GRACEFUL); ap_relieve_child_processes(event_note_child_killed); if (!child_fatal) { /* cleanup pid file on normal shutdown */ ap_remove_pid(pconf, ap_pid_fname); ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf, APLOGNO(00492) "caught " AP_SIG_GRACEFUL_STOP_STRING ", shutting down gracefully"); } if (ap_graceful_shutdown_timeout) { cutoff = apr_time_now() + apr_time_from_sec(ap_graceful_shutdown_timeout); } /* Don't really exit until each child has finished */ shutdown_pending = 0; do { /* Pause for a second */ apr_sleep(apr_time_from_sec(1)); /* Relieve any children which have now exited */ ap_relieve_child_processes(event_note_child_killed); active_children = 0; for (index = 0; index < ap_daemons_limit; ++index) { if (ap_mpm_safe_kill(MPM_CHILD_PID(index), 0) == APR_SUCCESS) { active_children = 1; /* Having just one child is enough to stay around */ break; } } } while (!shutdown_pending && active_children && (!ap_graceful_shutdown_timeout || apr_time_now() < cutoff)); /* We might be here because we received SIGTERM, either * way, try and make sure that all of our processes are * really dead. */ ap_mpm_podx_killpg(pod, ap_daemons_limit, AP_MPM_PODX_RESTART); ap_reclaim_child_processes(1, event_note_child_killed); return DONE; } /* we've been told to restart */ apr_signal(SIGHUP, SIG_IGN); if (one_process) { /* not worth thinking about */ return DONE; } /* 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. */ ++retained->my_generation; ap_scoreboard_image->global->running_generation = retained->my_generation; if (retained->is_graceful) { ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf, APLOGNO(00493) AP_SIG_GRACEFUL_STRING " received. Doing graceful restart"); /* wake up the children...time to die. But we'll have more soon */ ap_mpm_podx_killpg(pod, ap_daemons_limit, AP_MPM_PODX_GRACEFUL); /* 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_podx_killpg(pod, ap_daemons_limit, AP_MPM_PODX_RESTART); ap_reclaim_child_processes(1, /* Start with SIGTERM */ event_note_child_killed); ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf, APLOGNO(00494) "SIGHUP received. Attempting to restart"); } return OK; } /* 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 event_open_logs(apr_pool_t * p, apr_pool_t * plog, apr_pool_t * ptemp, server_rec * s) { int startup = 0; int level_flags = 0; apr_status_t rv; pconf = p; /* the reverse of pre_config, we want this only the first time around */ if (retained->module_loads == 1) { startup = 1; level_flags |= APLOG_STARTUP; } if ((num_listensocks = ap_setup_listeners(ap_server_conf)) < 1) { ap_log_error(APLOG_MARK, APLOG_ALERT | level_flags, 0, (startup ? NULL : s), "no listening sockets available, shutting down"); return DONE; } if (!one_process) { if ((rv = ap_mpm_podx_open(pconf, &pod))) { ap_log_error(APLOG_MARK, APLOG_CRIT | level_flags, rv, (startup ? NULL : s), "could not open pipe-of-death"); return DONE; } } return OK; } static int event_pre_config(apr_pool_t * pconf, apr_pool_t * plog, apr_pool_t * ptemp) { int no_detach, debug, foreground; apr_status_t rv; const char *userdata_key = "mpm_eventopt_module"; mpm_state = AP_MPMQ_STARTING; 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 */ retained = ap_retained_data_get(userdata_key); if (!retained) { retained = ap_retained_data_create(userdata_key, sizeof(*retained)); retained->max_daemons_limit = -1; retained->idle_spawn_rate = 1; } ++retained->module_loads; if (retained->module_loads == 2) { int i; static apr_uint32_t foo = 0; apr_atomic_inc32(&foo); apr_atomic_dec32(&foo); apr_atomic_dec32(&foo); i = apr_atomic_dec32(&foo); if (i >= 0) { ap_log_error(APLOG_MARK, APLOG_CRIT, 0, NULL, APLOGNO(02406) "atomics not working as expected"); return HTTP_INTERNAL_SERVER_ERROR; } rv = apr_pollset_create(&event_pollset, 1, plog, APR_POLLSET_WAKEABLE|APR_POLLSET_NOCOPY); if (rv != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_CRIT, rv, NULL, APLOGNO(00495) "apr_pollset_create failed; check system or user limits"); return HTTP_INTERNAL_SERVER_ERROR; } apr_pollset_destroy(event_pollset); if (!one_process && !foreground) { /* before we detach, setup crash handlers to log to errorlog */ ap_fatal_signal_setup(ap_server_conf, pconf); 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, APLOGNO(00496) "apr_proc_detach failed"); return HTTP_INTERNAL_SERVER_ERROR; } } } parent_pid = ap_my_pid = getpid(); 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; server_limit = DEFAULT_SERVER_LIMIT; thread_limit = DEFAULT_THREAD_LIMIT; ap_daemons_limit = server_limit; threads_per_child = DEFAULT_THREADS_PER_CHILD; max_workers = ap_daemons_limit * threads_per_child; ap_extended_status = 0; return OK; } static int event_check_config(apr_pool_t *p, apr_pool_t *plog, apr_pool_t *ptemp, server_rec *s) { int startup = 0; /* the reverse of pre_config, we want this only the first time around */ if (retained->module_loads == 1) { startup = 1; } if (server_limit > MAX_SERVER_LIMIT) { if (startup) { ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, APLOGNO(00497) "WARNING: ServerLimit of %d exceeds compile-time " "limit of", server_limit); ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, " %d servers, decreasing to %d.", MAX_SERVER_LIMIT, MAX_SERVER_LIMIT); } else { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(00498) "ServerLimit of %d exceeds compile-time limit " "of %d, decreasing to match", server_limit, MAX_SERVER_LIMIT); } server_limit = MAX_SERVER_LIMIT; } else if (server_limit < 1) { if (startup) { ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, APLOGNO(00499) "WARNING: ServerLimit of %d not allowed, " "increasing to 1.", server_limit); } else { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(00500) "ServerLimit of %d not allowed, increasing to 1", server_limit); } server_limit = 1; } /* you cannot change ServerLimit across a restart; ignore * any such attempts */ if (!retained->first_server_limit) { retained->first_server_limit = server_limit; } else if (server_limit != retained->first_server_limit) { /* don't need a startup console version here */ ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(00501) "changing ServerLimit to %d from original value of %d " "not allowed during restart", server_limit, retained->first_server_limit); server_limit = retained->first_server_limit; } if (thread_limit > MAX_THREAD_LIMIT) { if (startup) { ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, APLOGNO(00502) "WARNING: ThreadLimit of %d exceeds compile-time " "limit of", thread_limit); ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, " %d threads, decreasing to %d.", MAX_THREAD_LIMIT, MAX_THREAD_LIMIT); } else { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(00503) "ThreadLimit of %d exceeds compile-time limit " "of %d, decreasing to match", thread_limit, MAX_THREAD_LIMIT); } thread_limit = MAX_THREAD_LIMIT; } else if (thread_limit < 1) { if (startup) { ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, APLOGNO(00504) "WARNING: ThreadLimit of %d not allowed, " "increasing to 1.", thread_limit); } else { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(00505) "ThreadLimit of %d not allowed, increasing to 1", thread_limit); } thread_limit = 1; } /* you cannot change ThreadLimit across a restart; ignore * any such attempts */ if (!retained->first_thread_limit) { retained->first_thread_limit = thread_limit; } else if (thread_limit != retained->first_thread_limit) { /* don't need a startup console version here */ ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(00506) "changing ThreadLimit to %d from original value of %d " "not allowed during restart", thread_limit, retained->first_thread_limit); thread_limit = retained->first_thread_limit; } if (threads_per_child > thread_limit) { if (startup) { ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, APLOGNO(00507) "WARNING: ThreadsPerChild of %d exceeds ThreadLimit " "of", threads_per_child); ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, " %d threads, decreasing to %d.", thread_limit, thread_limit); ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, " To increase, please see the ThreadLimit " "directive."); } else { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(00508) "ThreadsPerChild of %d exceeds ThreadLimit " "of %d, decreasing to match", threads_per_child, thread_limit); } threads_per_child = thread_limit; } else if (threads_per_child < 1) { if (startup) { ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, APLOGNO(00509) "WARNING: ThreadsPerChild of %d not allowed, " "increasing to 1.", threads_per_child); } else { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(00510) "ThreadsPerChild of %d not allowed, increasing to 1", threads_per_child); } threads_per_child = 1; } if (max_workers < threads_per_child) { if (startup) { ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, APLOGNO(00511) "WARNING: MaxRequestWorkers of %d is less than " "ThreadsPerChild of", max_workers); ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, " %d, increasing to %d. MaxRequestWorkers must be at " "least as large", threads_per_child, threads_per_child); ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, " as the number of threads in a single server."); } else { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(00512) "MaxRequestWorkers of %d is less than ThreadsPerChild " "of %d, increasing to match", max_workers, threads_per_child); } max_workers = threads_per_child; } ap_daemons_limit = max_workers / threads_per_child; if (max_workers % threads_per_child) { int tmp_max_workers = ap_daemons_limit * threads_per_child; if (startup) { ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, APLOGNO(00513) "WARNING: MaxRequestWorkers of %d is not an integer " "multiple of", max_workers); ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, " ThreadsPerChild of %d, decreasing to nearest " "multiple %d,", threads_per_child, tmp_max_workers); ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, " for a maximum of %d servers.", ap_daemons_limit); } else { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(00514) "MaxRequestWorkers of %d is not an integer multiple " "of ThreadsPerChild of %d, decreasing to nearest " "multiple %d", max_workers, threads_per_child, tmp_max_workers); } max_workers = tmp_max_workers; } if (ap_daemons_limit > server_limit) { if (startup) { ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, APLOGNO(00515) "WARNING: MaxRequestWorkers of %d would require %d " "servers and ", max_workers, ap_daemons_limit); ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, " would exceed ServerLimit of %d, decreasing to %d.", server_limit, server_limit * threads_per_child); ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, " To increase, please see the ServerLimit " "directive."); } else { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(00516) "MaxRequestWorkers of %d would require %d servers and " "exceed ServerLimit of %d, decreasing to %d", max_workers, ap_daemons_limit, server_limit, server_limit * threads_per_child); } ap_daemons_limit = server_limit; } /* ap_daemons_to_start > ap_daemons_limit checked in ap_mpm_run() */ if (ap_daemons_to_start < 0) { if (startup) { ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, APLOGNO(00517) "WARNING: StartServers of %d not allowed, " "increasing to 1.", ap_daemons_to_start); } else { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(00518) "StartServers of %d not allowed, increasing to 1", ap_daemons_to_start); } ap_daemons_to_start = 1; } if (min_spare_threads < 1) { if (startup) { ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, APLOGNO(00519) "WARNING: MinSpareThreads of %d not allowed, " "increasing to 1", min_spare_threads); ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, " to avoid almost certain server failure."); ap_log_error(APLOG_MARK, APLOG_WARNING | APLOG_STARTUP, 0, NULL, " Please read the documentation."); } else { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(00520) "MinSpareThreads of %d not allowed, increasing to 1", min_spare_threads); } min_spare_threads = 1; } /* max_spare_threads < min_spare_threads + threads_per_child * checked in ap_mpm_run() */ return OK; } static void event_hooks(apr_pool_t * p) { /* Our open_logs hook function 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; force_set_tz(p); ap_hook_open_logs(event_open_logs, NULL, aszSucc, APR_HOOK_REALLY_FIRST); /* 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(event_pre_config, NULL, NULL, APR_HOOK_REALLY_FIRST); ap_hook_check_config(event_check_config, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_mpm(event_run, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_mpm_query(event_query, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_mpm_register_timed_callback(event_register_timed_callback, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_mpm_get_name(event_get_name, NULL, NULL, APR_HOOK_MIDDLE); } 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); 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_workers(cmd_parms * cmd, void *dummy, const char *arg) { const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } if (!strcasecmp(cmd->cmd->name, "MaxClients")) { ap_log_error(APLOG_MARK, APLOG_INFO, 0, NULL, APLOGNO(00521) "MaxClients is deprecated, use MaxRequestWorkers " "instead."); } max_workers = atoi(arg); 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; } threads_per_child = atoi(arg); return NULL; } static const char *set_server_limit (cmd_parms *cmd, void *dummy, const char *arg) { const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } server_limit = atoi(arg); return NULL; } static const char *set_thread_limit(cmd_parms * cmd, void *dummy, const char *arg) { const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } thread_limit = atoi(arg); return NULL; } static const char *set_worker_factor(cmd_parms * cmd, void *dummy, const char *arg) { double val; char *endptr; const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } val = strtod(arg, &endptr); if (*endptr) return "error parsing value"; worker_factor = val * WORKER_FACTOR_SCALE; if (worker_factor == 0) worker_factor = 1; return NULL; } static const command_rec event_cmds[] = { LISTEN_COMMANDS, AP_INIT_TAKE1("StartServers", set_daemons_to_start, NULL, RSRC_CONF, "Number of child processes launched at server startup"), AP_INIT_TAKE1("ServerLimit", set_server_limit, NULL, RSRC_CONF, "Maximum number of child processes for this run of Apache"), 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_workers, NULL, RSRC_CONF, "Deprecated name of MaxRequestWorkers"), AP_INIT_TAKE1("MaxRequestWorkers", set_max_workers, 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("ThreadLimit", set_thread_limit, NULL, RSRC_CONF, "Maximum number of worker threads per child process for this " "run of Apache - Upper limit for ThreadsPerChild"), AP_INIT_TAKE1("AsyncRequestWorkerFactor", set_worker_factor, NULL, RSRC_CONF, "How many additional connects will be accepted per idle " "worker thread"), AP_GRACEFUL_SHUTDOWN_TIMEOUT_COMMAND, {NULL} }; AP_DECLARE_MODULE(mpm_eventopt) = { MPM20_MODULE_STUFF, NULL, /* 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 */ event_cmds, /* command apr_table_t */ event_hooks /* register_hooks */ };