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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 15:01:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 15:01:30 +0000
commit6beeb1b708550be0d4a53b272283e17e5e35fe17 (patch)
tree1ce8673d4aaa948e5554000101f46536a1e4cc29 /server/mpm/event
parentInitial commit. (diff)
downloadapache2-6beeb1b708550be0d4a53b272283e17e5e35fe17.tar.xz
apache2-6beeb1b708550be0d4a53b272283e17e5e35fe17.zip
Adding upstream version 2.4.57.upstream/2.4.57
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'server/mpm/event')
-rw-r--r--server/mpm/event/Makefile.in1
-rw-r--r--server/mpm/event/config.m415
-rw-r--r--server/mpm/event/config3.m47
-rw-r--r--server/mpm/event/event.c4078
-rw-r--r--server/mpm/event/mpm_default.h56
5 files changed, 4157 insertions, 0 deletions
diff --git a/server/mpm/event/Makefile.in b/server/mpm/event/Makefile.in
new file mode 100644
index 0000000..f34af9c
--- /dev/null
+++ b/server/mpm/event/Makefile.in
@@ -0,0 +1 @@
+include $(top_srcdir)/build/special.mk
diff --git a/server/mpm/event/config.m4 b/server/mpm/event/config.m4
new file mode 100644
index 0000000..c891c75
--- /dev/null
+++ b/server/mpm/event/config.m4
@@ -0,0 +1,15 @@
+AC_MSG_CHECKING(if event MPM supports this platform)
+if test $forking_mpms_supported != yes; then
+ AC_MSG_RESULT(no - This is not a forking platform)
+elif test $ac_cv_define_APR_HAS_THREADS != yes; then
+ AC_MSG_RESULT(no - APR does not support threads)
+elif test $have_threaded_sig_graceful != yes; then
+ AC_MSG_RESULT(no - SIG_GRACEFUL cannot be used with a threaded MPM)
+elif test $ac_cv_have_threadsafe_pollset != yes; then
+ AC_MSG_RESULT(no - APR_POLLSET_THREADSAFE is not supported)
+elif test $apr_has_skiplist != yes; then
+ AC_MSG_RESULT(no - APR skiplist is not available, need APR 1.5.x or later)
+else
+ AC_MSG_RESULT(yes)
+ APACHE_MPM_SUPPORTED(event, yes, yes)
+fi
diff --git a/server/mpm/event/config3.m4 b/server/mpm/event/config3.m4
new file mode 100644
index 0000000..09d3626
--- /dev/null
+++ b/server/mpm/event/config3.m4
@@ -0,0 +1,7 @@
+dnl ## XXX - Need a more thorough check of the proper flags to use
+
+APACHE_SUBST(MOD_MPM_EVENT_LDADD)
+
+APACHE_MPM_MODULE(event, $enable_mpm_event, event.lo,[
+ AC_CHECK_FUNCS(pthread_kill)
+], , [\$(MOD_MPM_EVENT_LDADD)])
diff --git a/server/mpm/event/event.c b/server/mpm/event/event.c
new file mode 100644
index 0000000..3672f44
--- /dev/null
+++ b/server/mpm/event/event.c
@@ -0,0 +1,4078 @@
+/* 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
+ * significant 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 Listening 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 does not perform 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_version.h"
+
+#include <stdlib.h>
+
+#if APR_HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#if APR_HAVE_SYS_SOCKET_H
+#include <sys/socket.h>
+#endif
+#if APR_HAVE_SYS_WAIT_H
+#include <sys/wait.h>
+#endif
+#ifdef HAVE_SYS_PROCESSOR_H
+#include <sys/processor.h> /* for bindprocessor() */
+#endif
+
+#if !APR_HAS_THREADS
+#error The Event 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 "http_protocol.h"
+#include "ap_mpm.h"
+#include "mpm_common.h"
+#include "ap_listen.h"
+#include "scoreboard.h"
+#include "mpm_fdqueue.h"
+#include "mpm_default.h"
+#include "http_vhost.h"
+#include "unixd.h"
+#include "apr_skiplist.h"
+
+#include <signal.h>
+#include <limits.h> /* for INT_MAX */
+
+
+/* Limit on the total --- clients will be locked out if more servers than
+ * this are needed. It is intended solely to keep the server from crashing
+ * when things get out of hand.
+ *
+ * We keep a hard maximum number of servers, for two reasons --- first off,
+ * in case something goes seriously wrong, we want to stop the fork bomb
+ * short of actually crashing the machine we're running on by filling some
+ * kernel table. Secondly, it keeps the size of the scoreboard file small
+ * enough that we can read the whole thing without worrying too much about
+ * the overhead.
+ */
+#ifndef DEFAULT_SERVER_LIMIT
+#define DEFAULT_SERVER_LIMIT 16
+#endif
+
+/* Admin can't tune ServerLimit beyond MAX_SERVER_LIMIT. We want
+ * some sort of compile-time limit to help catch typos.
+ */
+#ifndef MAX_SERVER_LIMIT
+#define MAX_SERVER_LIMIT 20000
+#endif
+
+/* Limit on the threads per process. Clients will be locked out if more than
+ * this 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)
+
+#if !APR_VERSION_AT_LEAST(1,4,0)
+#define apr_time_from_msec(x) (x * 1000)
+#endif
+
+#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;
+ /* AsyncRequestWorkerFactor * 16 */
+
+static int threads_per_child = 0; /* ThreadsPerChild */
+static int ap_daemons_to_start = 0; /* StartServers */
+static int min_spare_threads = 0; /* MinSpareThreads */
+static int max_spare_threads = 0; /* MaxSpareThreads */
+static int active_daemons_limit = 0; /* MaxRequestWorkers / ThreadsPerChild */
+static int max_workers = 0; /* MaxRequestWorkers */
+static int server_limit = 0; /* ServerLimit */
+static int thread_limit = 0; /* ThreadLimit */
+static int had_healthy_child = 0;
+static volatile int dying = 0;
+static volatile int workers_may_exit = 0;
+static volatile int start_thread_may_exit = 0;
+static volatile int listener_may_exit = 0;
+static int listener_is_wakeable = 0; /* Pollset supports APR_POLLSET_WAKEABLE */
+static int num_listensocks = 0;
+static apr_int32_t conns_this_child; /* MaxConnectionsPerChild, only access
+ in listener thread */
+static apr_uint32_t connection_count = 0; /* Number of open connections */
+static apr_uint32_t lingering_count = 0; /* Number of connections in lingering close */
+static apr_uint32_t suspended_count = 0; /* Number of suspended connections */
+static apr_uint32_t clogged_count = 0; /* Number of threads processing ssl conns */
+static apr_uint32_t threads_shutdown = 0; /* Number of threads that have shutdown
+ early during graceful termination */
+static int resource_shortage = 0;
+static fd_queue_t *worker_queue;
+static fd_queue_info_t *worker_queue_info;
+
+static apr_thread_mutex_t *timeout_mutex;
+
+module AP_MODULE_DECLARE_DATA mpm_event_module;
+
+/* forward declare */
+struct event_srv_cfg_s;
+typedef struct event_srv_cfg_s event_srv_cfg;
+
+static apr_pollfd_t *listener_pollfd;
+
+/*
+ * 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;
+
+typedef struct event_conn_state_t event_conn_state_t;
+
+/*
+ * The chain of connections to be shutdown by a worker thread (deferred),
+ * linked list updated atomically.
+ */
+static event_conn_state_t *volatile defer_linger_chain;
+
+struct event_conn_state_t {
+ /** APR_RING of expiration timeouts */
+ APR_RING_ENTRY(event_conn_state_t) timeout_list;
+ /** the time when the entry was queued */
+ apr_time_t queue_timestamp;
+ /** connection record this struct refers to */
+ conn_rec *c;
+ /** request record (if any) this struct refers to */
+ request_rec *r;
+ /** server config this struct refers to */
+ event_srv_cfg *sc;
+ /** scoreboard handle for the conn_rec */
+ ap_sb_handle_t *sbh;
+ /** is the current conn_rec suspended? (disassociated with
+ * a particular MPM thread; for suspend_/resume_connection
+ * hooks)
+ */
+ int suspended;
+ /** 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;
+ /** chaining in defer_linger_chain */
+ struct event_conn_state_t *chain;
+ /** Is lingering close from defer_lingering_close()? */
+ int deferred_linger;
+};
+
+APR_RING_HEAD(timeout_head_t, event_conn_state_t);
+
+struct timeout_queue {
+ struct timeout_head_t head;
+ apr_interval_time_t timeout;
+ apr_uint32_t count; /* for this queue */
+ apr_uint32_t *total; /* for all chained/related queues */
+ struct timeout_queue *next; /* chaining */
+};
+/*
+ * Several timeout queues that use different timeouts, so that we always can
+ * simply append to the end.
+ * write_completion_q uses vhost's TimeOut
+ * keepalive_q uses vhost's 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 volatile apr_time_t queues_next_expiry;
+
+/* Prevent extra poll/wakeup calls for timeouts close in the future (queues
+ * have the granularity of a second anyway).
+ * XXX: Wouldn't 0.5s (instead of 0.1s) be "enough"?
+ */
+#define TIMEOUT_FUDGE_FACTOR apr_time_from_msec(100)
+
+/*
+ * Macros for accessing struct timeout_queue.
+ * For TO_QUEUE_APPEND and TO_QUEUE_REMOVE, timeout_mutex must be held.
+ */
+static void TO_QUEUE_APPEND(struct timeout_queue *q, event_conn_state_t *el)
+{
+ apr_time_t elem_expiry;
+ apr_time_t next_expiry;
+
+ APR_RING_INSERT_TAIL(&q->head, el, event_conn_state_t, timeout_list);
+ ++*q->total;
+ ++q->count;
+
+ /* Cheaply update the global queues_next_expiry with the one of the
+ * first entry of this queue (oldest) if it expires before.
+ */
+ el = APR_RING_FIRST(&q->head);
+ elem_expiry = el->queue_timestamp + q->timeout;
+ next_expiry = queues_next_expiry;
+ if (!next_expiry || next_expiry > elem_expiry + TIMEOUT_FUDGE_FACTOR) {
+ queues_next_expiry = elem_expiry;
+ /* Unblock the poll()ing listener for it to update its timeout. */
+ if (listener_is_wakeable) {
+ apr_pollset_wakeup(event_pollset);
+ }
+ }
+}
+
+static void TO_QUEUE_REMOVE(struct timeout_queue *q, event_conn_state_t *el)
+{
+ APR_RING_REMOVE(el, timeout_list);
+ APR_RING_ELEM_INIT(el, timeout_list);
+ --*q->total;
+ --q->count;
+}
+
+static struct timeout_queue *TO_QUEUE_MAKE(apr_pool_t *p, apr_time_t t,
+ struct timeout_queue *ref)
+{
+ struct timeout_queue *q;
+
+ q = apr_pcalloc(p, sizeof *q);
+ APR_RING_INIT(&q->head, event_conn_state_t, timeout_list);
+ q->total = (ref) ? ref->total : apr_pcalloc(p, sizeof *q->total);
+ q->timeout = t;
+
+ return q;
+}
+
+#define TO_QUEUE_ELEM_INIT(el) \
+ APR_RING_ELEM_INIT((el), timeout_list)
+
+/* The structure used to pass unique initialization info to each thread */
+typedef struct
+{
+ int pslot; /* process slot */
+ int tslot; /* worker slot of the thread */
+} 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
+} 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 {
+ ap_unixd_mpm_retained_data *mpm;
+
+ int first_server_limit;
+ int first_thread_limit;
+ int sick_child_detected;
+ int maxclients_reported;
+ int near_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_daemon_used;
+
+ /*
+ * All running workers, active and shutting down, including those that
+ * may be left from before a graceful restart.
+ * Not kept up-to-date when shutdown is pending.
+ */
+ int total_daemons;
+ /*
+ * Workers that still active, i.e. are not shutting down gracefully.
+ */
+ int active_daemons;
+ /*
+ * 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
+ * maintained per listeners bucket, 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;
+
+typedef struct event_child_bucket {
+ ap_pod_t *pod;
+ ap_listen_rec *listeners;
+} event_child_bucket;
+static event_child_bucket *all_buckets, /* All listeners buckets */
+ *my_bucket; /* Current child bucket */
+
+struct event_srv_cfg_s {
+ struct timeout_queue *wc_q,
+ *ka_q;
+};
+
+#define ID_FROM_CHILD_THREAD(c, t) ((c * thread_limit) + t)
+
+/* The event 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 apr_pool_t *pruntime; /* Pool for MPM threads 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;
+
+static int ap_child_slot; /* Current child process slot in scoreboard */
+
+/* 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 volatile apr_uint32_t listensocks_disabled;
+
+static void disable_listensocks(void)
+{
+ int i;
+ if (apr_atomic_cas32(&listensocks_disabled, 1, 0) != 0) {
+ return;
+ }
+ if (event_pollset) {
+ for (i = 0; i < num_listensocks; i++) {
+ apr_pollset_remove(event_pollset, &listener_pollfd[i]);
+ }
+ }
+ ap_scoreboard_image->parent[ap_child_slot].not_accepting = 1;
+}
+
+static void enable_listensocks(void)
+{
+ int i;
+ if (listener_may_exit
+ || apr_atomic_cas32(&listensocks_disabled, 0, 1) != 1) {
+ return;
+ }
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, APLOGNO(00457)
+ "Accepting new connections again: "
+ "%u active conns (%u lingering/%u clogged/%u suspended), "
+ "%u idle workers",
+ apr_atomic_read32(&connection_count),
+ apr_atomic_read32(&lingering_count),
+ apr_atomic_read32(&clogged_count),
+ apr_atomic_read32(&suspended_count),
+ ap_queue_info_num_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[ap_child_slot].not_accepting = 0;
+}
+
+static APR_INLINE apr_uint32_t listeners_disabled(void)
+{
+ return apr_atomic_read32(&listensocks_disabled);
+}
+
+static APR_INLINE int connections_above_limit(int *busy)
+{
+ apr_uint32_t i_count = ap_queue_info_num_idlers(worker_queue_info);
+ if (i_count > 0) {
+ apr_uint32_t c_count = apr_atomic_read32(&connection_count);
+ apr_uint32_t l_count = apr_atomic_read32(&lingering_count);
+ if (c_count <= l_count
+ /* Off by 'listeners_disabled()' to avoid flip flop */
+ || c_count - l_count < (apr_uint32_t)threads_per_child +
+ (i_count - listeners_disabled()) *
+ (worker_factor / WORKER_FACTOR_SCALE)) {
+ return 0;
+ }
+ }
+ else if (busy) {
+ *busy = 1;
+ }
+ return 1;
+}
+
+static APR_INLINE int should_enable_listensocks(void)
+{
+ return !dying && listeners_disabled() && !connections_above_limit(NULL);
+}
+
+static void close_socket_nonblocking_(apr_socket_t *csd,
+ const char *from, int line)
+{
+ apr_status_t rv;
+ apr_os_sock_t fd = -1;
+
+ /* close_worker_sockets() may have closed it already */
+ rv = apr_os_sock_get(&fd, csd);
+ ap_log_error(APLOG_MARK, APLOG_TRACE8, 0, ap_server_conf,
+ "closing socket %i/%pp from %s:%i", (int)fd, csd, from, line);
+ if (rv == APR_SUCCESS && fd == -1) {
+ return;
+ }
+
+ apr_socket_timeout_set(csd, 0);
+ 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);
+ }
+}
+#define close_socket_nonblocking(csd) \
+ close_socket_nonblocking_(csd, __FUNCTION__, __LINE__)
+
+static void close_worker_sockets(void)
+{
+ int i;
+ for (i = 0; i < threads_per_child; i++) {
+ apr_socket_t *csd = worker_sockets[i];
+ if (csd) {
+ worker_sockets[i] = NULL;
+ close_socket_nonblocking(csd);
+ }
+ }
+}
+
+static void wakeup_listener(void)
+{
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf,
+ "wake up listener%s", listener_may_exit ? " again" : "");
+
+ listener_may_exit = 1;
+ disable_listensocks();
+
+ /* Unblock the listener if it's poll()ing */
+ if (event_pollset && listener_is_wakeable) {
+ apr_pollset_wakeup(event_pollset);
+ }
+
+ /* unblock the listener if it's waiting for a worker */
+ if (worker_queue_info) {
+ ap_queue_info_term(worker_queue_info);
+ }
+
+ if (!listener_os_thread) {
+ /* XXX there is an obscure path that this doesn't handle perfectly:
+ * right after listener thread is created but before
+ * listener_os_thread is set, the first worker thread hits an
+ * error and starts graceful termination
+ */
+ return;
+ }
+ /*
+ * we should just be able to "kill(ap_my_pid, LISTENER_SIGNAL)" on all
+ * platforms and wake up the listener thread since it is the only thread
+ * with SIGHUP unblocked, but that doesn't work on Linux
+ */
+#ifdef HAVE_PTHREAD_KILL
+ pthread_kill(*listener_os_thread, LISTENER_SIGNAL);
+#else
+ kill(ap_my_pid, LISTENER_SIGNAL);
+#endif
+}
+
+#define ST_INIT 0
+#define ST_GRACEFUL 1
+#define ST_UNGRACEFUL 2
+
+static int terminate_mode = ST_INIT;
+
+static void signal_threads(int mode)
+{
+ if (terminate_mode >= mode) {
+ return;
+ }
+ terminate_mode = mode;
+ retained->mpm->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 */
+ }
+
+ ap_run_child_stopping(pchild, mode == ST_GRACEFUL);
+}
+
+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_daemon_used;
+ 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_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 = active_daemons_limit;
+ break;
+ case AP_MPMQ_MPM_STATE:
+ *result = retained->mpm->mpm_state;
+ break;
+ case AP_MPMQ_GENERATION:
+ *result = retained->mpm->my_generation;
+ break;
+ default:
+ *rv = APR_ENOTIMPL;
+ break;
+ }
+ return OK;
+}
+
+static void event_note_child_stopped(int slot, pid_t pid, ap_generation_t gen)
+{
+ if (slot != -1) { /* child had a scoreboard slot? */
+ process_score *ps = &ap_scoreboard_image->parent[slot];
+ int i;
+
+ pid = ps->pid;
+ gen = ps->generation;
+ for (i = 0; i < threads_per_child; i++) {
+ ap_update_child_status_from_indexes(slot, i, SERVER_DEAD, NULL);
+ }
+ ap_run_child_status(ap_server_conf, pid, gen, slot, MPM_CHILD_EXITED);
+ if (ps->quiescing != 2) { /* vs perform_idle_server_maintenance() */
+ retained->active_daemons--;
+ }
+ retained->total_daemons--;
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf,
+ "Child %d stopped: pid %d, gen %d, "
+ "active %d/%d, total %d/%d/%d, quiescing %d",
+ slot, (int)pid, (int)gen,
+ retained->active_daemons, active_daemons_limit,
+ retained->total_daemons, retained->max_daemon_used,
+ server_limit, ps->quiescing);
+ ps->not_accepting = 0;
+ ps->quiescing = 0;
+ ps->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_generation_t gen = retained->mpm->my_generation;
+
+ retained->total_daemons++;
+ retained->active_daemons++;
+ ap_scoreboard_image->parent[slot].pid = pid;
+ ap_scoreboard_image->parent[slot].generation = gen;
+ ap_run_child_status(ap_server_conf, pid, gen, slot, MPM_CHILD_STARTED);
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf,
+ "Child %d started: pid %d, gen %d, "
+ "active %d/%d, total %d/%d/%d",
+ slot, (int)pid, (int)gen,
+ retained->active_daemons, active_daemons_limit,
+ retained->total_daemons, retained->max_daemon_used,
+ server_limit);
+}
+
+static const char *event_get_name(void)
+{
+ return "event";
+}
+
+/* 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)
+{
+ retained->mpm->mpm_state = AP_MPMQ_STOPPING;
+ if (terminate_mode == ST_INIT) {
+ ap_run_child_stopping(pchild, 0);
+ }
+
+ if (pchild) {
+ apr_pool_destroy(pchild);
+ }
+
+ if (one_process) {
+ event_note_child_stopped(/* slot */ 0, 0, 0);
+ }
+
+ exit(code);
+}
+
+static void just_die(int sig)
+{
+ clean_child_exit(0);
+}
+
+/*****************************************************************
+ * Connection structures and accounting...
+ */
+
+static int child_fatal;
+
+static apr_status_t decrement_connection_count(void *cs_)
+{
+ int is_last_connection;
+ event_conn_state_t *cs = cs_;
+ ap_log_cerror(APLOG_MARK, APLOG_TRACE8, 0, cs->c,
+ "cleanup connection from state %i", (int)cs->pub.state);
+ switch (cs->pub.state) {
+ case CONN_STATE_LINGER:
+ case CONN_STATE_LINGER_NORMAL:
+ case CONN_STATE_LINGER_SHORT:
+ apr_atomic_dec32(&lingering_count);
+ break;
+ case CONN_STATE_SUSPENDED:
+ apr_atomic_dec32(&suspended_count);
+ break;
+ default:
+ break;
+ }
+ /* Unblock the listener if it's waiting for connection_count = 0,
+ * or if the listening sockets were disabled due to limits and can
+ * now accept new connections.
+ */
+ is_last_connection = !apr_atomic_dec32(&connection_count);
+ if (listener_is_wakeable
+ && ((is_last_connection && listener_may_exit)
+ || should_enable_listensocks())) {
+ apr_pollset_wakeup(event_pollset);
+ }
+ if (dying) {
+ /* Help worker_thread_should_exit_early() */
+ ap_queue_interrupt_one(worker_queue);
+ }
+ return APR_SUCCESS;
+}
+
+static void notify_suspend(event_conn_state_t *cs)
+{
+ ap_run_suspend_connection(cs->c, cs->r);
+ cs->c->sbh = NULL;
+ cs->suspended = 1;
+}
+
+static void notify_resume(event_conn_state_t *cs, int cleanup)
+{
+ cs->suspended = 0;
+ cs->c->sbh = cleanup ? NULL : cs->sbh;
+ ap_run_resume_connection(cs->c, cs->r);
+}
+
+/*
+ * Defer flush and close of the connection by adding it to defer_linger_chain,
+ * for a worker to grab it and do the job (should that be blocking).
+ * Pre-condition: nonblocking, can be called from anywhere provided cs is not
+ * in any timeout queue or in the pollset.
+ */
+static int defer_lingering_close(event_conn_state_t *cs)
+{
+ ap_log_cerror(APLOG_MARK, APLOG_TRACE6, 0, cs->c,
+ "deferring close from state %i", (int)cs->pub.state);
+
+ /* The connection is not shutdown() yet strictly speaking, but it's not
+ * in any queue nor handled by a worker either (will be very soon), so
+ * to account for it somewhere we bump lingering_count now (and set
+ * deferred_linger for process_lingering_close() to know).
+ */
+ cs->pub.state = CONN_STATE_LINGER;
+ apr_atomic_inc32(&lingering_count);
+ cs->deferred_linger = 1;
+ for (;;) {
+ event_conn_state_t *chain = cs->chain = defer_linger_chain;
+ if (apr_atomic_casptr((void *)&defer_linger_chain, cs,
+ chain) != chain) {
+ /* Race lost, try again */
+ continue;
+ }
+ return 1;
+ }
+}
+
+/* Close the connection and release its resources (ptrans), either because an
+ * unrecoverable error occured (queues or pollset add/remove) or more usually
+ * if lingering close timed out.
+ * Pre-condition: nonblocking, can be called from anywhere provided cs is not
+ * in any timeout queue or in the pollset.
+ */
+static void close_connection(event_conn_state_t *cs)
+{
+ ap_log_cerror(APLOG_MARK, APLOG_TRACE6, 0, cs->c,
+ "closing connection from state %i", (int)cs->pub.state);
+
+ close_socket_nonblocking(cs->pfd.desc.s);
+ ap_queue_info_push_pool(worker_queue_info, cs->p);
+}
+
+/* Shutdown the connection in case of timeout, error or resources shortage.
+ * This starts short lingering close if not already there, or directly closes
+ * the connection otherwise.
+ * Pre-condition: nonblocking, can be called from anywhere provided cs is not
+ * in any timeout queue or in the pollset.
+ */
+static int shutdown_connection(event_conn_state_t *cs)
+{
+ if (cs->pub.state < CONN_STATE_LINGER) {
+ apr_table_setn(cs->c->notes, "short-lingering-close", "1");
+ defer_lingering_close(cs);
+ }
+ else {
+ close_connection(cs);
+ }
+ return 1;
+}
+
+/*
+ * This runs before any non-MPM cleanup code on the connection;
+ * if the connection is currently suspended as far as modules
+ * know, provide notification of resumption.
+ */
+static apr_status_t ptrans_pre_cleanup(void *dummy)
+{
+ event_conn_state_t *cs = dummy;
+
+ if (cs->suspended) {
+ notify_resume(cs, 1);
+ }
+ return APR_SUCCESS;
+}
+
+/*
+ * event_pre_read_request() and event_request_cleanup() track the
+ * current r for a given connection.
+ */
+static apr_status_t event_request_cleanup(void *dummy)
+{
+ conn_rec *c = dummy;
+ event_conn_state_t *cs = ap_get_module_config(c->conn_config,
+ &mpm_event_module);
+
+ cs->r = NULL;
+ return APR_SUCCESS;
+}
+
+static void event_pre_read_request(request_rec *r, conn_rec *c)
+{
+ event_conn_state_t *cs = ap_get_module_config(c->conn_config,
+ &mpm_event_module);
+
+ cs->r = r;
+ cs->sc = ap_get_module_config(ap_server_conf->module_config,
+ &mpm_event_module);
+ apr_pool_cleanup_register(r->pool, c, event_request_cleanup,
+ apr_pool_cleanup_null);
+}
+
+/*
+ * event_post_read_request() tracks the current server config for a
+ * given request.
+ */
+static int event_post_read_request(request_rec *r)
+{
+ conn_rec *c = r->connection;
+ event_conn_state_t *cs = ap_get_module_config(c->conn_config,
+ &mpm_event_module);
+
+ /* To preserve legacy behaviour (consistent with other MPMs), use
+ * the keepalive timeout from the base server (first on this IP:port)
+ * when none is explicitly configured on this server.
+ */
+ if (r->server->keep_alive_timeout_set) {
+ cs->sc = ap_get_module_config(r->server->module_config,
+ &mpm_event_module);
+ }
+ else {
+ cs->sc = ap_get_module_config(c->base_server->module_config,
+ &mpm_event_module);
+ }
+ return OK;
+}
+
+/* Forward declare */
+static void process_lingering_close(event_conn_state_t *cs);
+
+static void update_reqevents_from_sense(event_conn_state_t *cs, int sense)
+{
+ if (sense < 0) {
+ sense = cs->pub.sense;
+ }
+ if (sense == CONN_SENSE_WANT_READ) {
+ cs->pfd.reqevents = APR_POLLIN | APR_POLLHUP;
+ }
+ else {
+ cs->pfd.reqevents = APR_POLLOUT;
+ }
+ /* POLLERR is usually returned event only, but some pollset
+ * backends may require it in reqevents to do the right thing,
+ * so it shouldn't hurt (ignored otherwise).
+ */
+ cs->pfd.reqevents |= APR_POLLERR;
+
+ /* Reset to default for the next round */
+ cs->pub.sense = CONN_SENSE_DEFAULT;
+}
+
+/*
+ * process one connection in the worker
+ */
+static void process_socket(apr_thread_t *thd, apr_pool_t * p, apr_socket_t * sock,
+ event_conn_state_t * cs, 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 clogging = 0;
+ apr_status_t rv;
+ int rc = OK;
+
+ 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);
+ ap_create_sb_handle(&cs->sbh, p, my_child_num, my_thread_num);
+ c = ap_run_create_connection(p, ap_server_conf, sock,
+ conn_id, cs->sbh, cs->bucket_alloc);
+ if (!c) {
+ ap_queue_info_push_pool(worker_queue_info, p);
+ return;
+ }
+ apr_atomic_inc32(&connection_count);
+ apr_pool_cleanup_register(c->pool, cs, decrement_connection_count,
+ apr_pool_cleanup_null);
+ ap_set_module_config(c->conn_config, &mpm_event_module, cs);
+ c->current_thread = thd;
+ c->cs = &cs->pub;
+ cs->c = c;
+ cs->p = p;
+ cs->sc = ap_get_module_config(ap_server_conf->module_config,
+ &mpm_event_module);
+ cs->pfd.desc_type = APR_POLL_SOCKET;
+ cs->pfd.desc.s = sock;
+ update_reqevents_from_sense(cs, CONN_SENSE_WANT_READ);
+ pt->type = PT_CSD;
+ pt->baton = cs;
+ cs->pfd.client_data = pt;
+ apr_pool_pre_cleanup_register(p, cs, ptrans_pre_cleanup);
+ TO_QUEUE_ELEM_INIT(cs);
+
+ ap_update_vhost_given_ip(c);
+
+ rc = ap_pre_connection(c, sock);
+ if (rc != OK && rc != DONE) {
+ ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, c, APLOGNO(00469)
+ "process_socket: connection aborted");
+ }
+
+ /**
+ * 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;
+
+ cs->pub.sense = CONN_SENSE_DEFAULT;
+ rc = OK;
+ }
+ else {
+ c = cs->c;
+ ap_update_sb_handle(cs->sbh, my_child_num, my_thread_num);
+ notify_resume(cs, 0);
+ c->current_thread = thd;
+ /* Subsequent request on a conn, and thread number is part of ID */
+ c->id = conn_id;
+ }
+
+ if (c->aborted) {
+ /* do lingering close below */
+ cs->pub.state = CONN_STATE_LINGER;
+ }
+ else if (cs->pub.state >= CONN_STATE_LINGER) {
+ /* fall through */
+ }
+ else {
+ if (cs->pub.state == CONN_STATE_READ_REQUEST_LINE
+ /* If we have an input filter which 'clogs' the input stream,
+ * like mod_ssl used to, lets just do the normal read from input
+ * filters, like the Worker MPM does. Filters that need to write
+ * where they would otherwise read, or read where they would
+ * otherwise write, should set the sense appropriately.
+ */
+ || c->clogging_input_filters) {
+read_request:
+ clogging = c->clogging_input_filters;
+ if (clogging) {
+ apr_atomic_inc32(&clogged_count);
+ }
+ rc = ap_run_process_connection(c);
+ if (clogging) {
+ apr_atomic_dec32(&clogged_count);
+ }
+ if (cs->pub.state > CONN_STATE_LINGER) {
+ cs->pub.state = CONN_STATE_LINGER;
+ }
+ if (rc == DONE) {
+ rc = OK;
+ }
+ }
+ }
+ /*
+ * The process_connection hooks above should set the connection state
+ * appropriately upon return, for event MPM to either:
+ * - do lingering close (CONN_STATE_LINGER),
+ * - wait for readability of the next request with respect to the keepalive
+ * timeout (state CONN_STATE_CHECK_REQUEST_LINE_READABLE),
+ * - wait for read/write-ability of the underlying socket with respect to
+ * its timeout by setting c->clogging_input_filters to 1 and the sense
+ * to CONN_SENSE_WANT_READ/WRITE (state CONN_STATE_WRITE_COMPLETION),
+ * - keep flushing the output filters stack in nonblocking mode, and then
+ * if required wait for read/write-ability of the underlying socket with
+ * respect to its own timeout (state CONN_STATE_WRITE_COMPLETION); since
+ * completion at some point may require reads (e.g. SSL_ERROR_WANT_READ),
+ * an output filter can also set the sense to CONN_SENSE_WANT_READ at any
+ * time for event MPM to do the right thing,
+ * - suspend the connection (SUSPENDED) such that it now interacts with
+ * the MPM through suspend/resume_connection() hooks, and/or registered
+ * poll callbacks (PT_USER), and/or registered timed callbacks triggered
+ * by timer events.
+ * If a process_connection hook returns an error or no hook sets the state
+ * to one of the above expected value, we forcibly close the connection w/
+ * CONN_STATE_LINGER. This covers the cases where no process_connection
+ * hook executes (DECLINED), or one returns OK w/o touching the state (i.e.
+ * CONN_STATE_READ_REQUEST_LINE remains after the call) which can happen
+ * with third-party modules not updated to work specifically with event MPM
+ * while this was expected to do lingering close unconditionally with
+ * worker or prefork MPMs for instance.
+ */
+ if (rc != OK || (cs->pub.state >= CONN_STATE_NUM)
+ || (cs->pub.state < CONN_STATE_LINGER
+ && cs->pub.state != CONN_STATE_WRITE_COMPLETION
+ && cs->pub.state != CONN_STATE_CHECK_REQUEST_LINE_READABLE
+ && cs->pub.state != CONN_STATE_SUSPENDED)) {
+ ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, c, APLOGNO(10111)
+ "process_socket: connection processing %s: closing",
+ rc ? apr_psprintf(c->pool, "returned error %i", rc)
+ : apr_psprintf(c->pool, "unexpected state %i",
+ (int)cs->pub.state));
+ 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(cs->sbh, SERVER_BUSY_WRITE, NULL);
+ 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 ||
+ cs->pub.sense == CONN_SENSE_WANT_READ) {
+ /* Still in WRITE_COMPLETION_STATE:
+ * Set a read/write timeout for this connection, and let the
+ * event thread poll for read/writeability.
+ */
+ cs->queue_timestamp = apr_time_now();
+ notify_suspend(cs);
+
+ update_reqevents_from_sense(cs, -1);
+ apr_thread_mutex_lock(timeout_mutex);
+ TO_QUEUE_APPEND(cs->sc->wc_q, cs);
+ rv = apr_pollset_add(event_pollset, &cs->pfd);
+ if (rv != APR_SUCCESS && !APR_STATUS_IS_EEXIST(rv)) {
+ AP_DEBUG_ASSERT(0);
+ TO_QUEUE_REMOVE(cs->sc->wc_q, cs);
+ apr_thread_mutex_unlock(timeout_mutex);
+ ap_log_error(APLOG_MARK, APLOG_ERR, rv, ap_server_conf, APLOGNO(03465)
+ "process_socket: apr_pollset_add failure for "
+ "write completion");
+ close_connection(cs);
+ signal_threads(ST_GRACEFUL);
+ }
+ else {
+ apr_thread_mutex_unlock(timeout_mutex);
+ }
+ return;
+ }
+ else if (c->keepalive != AP_CONN_KEEPALIVE || c->aborted) {
+ 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 if (!listener_may_exit) {
+ cs->pub.state = CONN_STATE_CHECK_REQUEST_LINE_READABLE;
+ }
+ else {
+ cs->pub.state = CONN_STATE_LINGER;
+ }
+ }
+
+ if (cs->pub.state == CONN_STATE_CHECK_REQUEST_LINE_READABLE) {
+ ap_update_child_status(cs->sbh, SERVER_BUSY_KEEPALIVE, NULL);
+
+ /* It greatly simplifies the logic to use a single timeout value per q
+ * 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->queue_timestamp = apr_time_now();
+ notify_suspend(cs);
+
+ /* Add work to pollset. */
+ update_reqevents_from_sense(cs, CONN_SENSE_WANT_READ);
+ apr_thread_mutex_lock(timeout_mutex);
+ TO_QUEUE_APPEND(cs->sc->ka_q, cs);
+ rv = apr_pollset_add(event_pollset, &cs->pfd);
+ if (rv != APR_SUCCESS && !APR_STATUS_IS_EEXIST(rv)) {
+ AP_DEBUG_ASSERT(0);
+ TO_QUEUE_REMOVE(cs->sc->ka_q, cs);
+ apr_thread_mutex_unlock(timeout_mutex);
+ ap_log_error(APLOG_MARK, APLOG_ERR, rv, ap_server_conf, APLOGNO(03093)
+ "process_socket: apr_pollset_add failure for "
+ "keep alive");
+ close_connection(cs);
+ signal_threads(ST_GRACEFUL);
+ }
+ else {
+ apr_thread_mutex_unlock(timeout_mutex);
+ }
+ return;
+ }
+
+ if (cs->pub.state == CONN_STATE_SUSPENDED) {
+ apr_atomic_inc32(&suspended_count);
+ notify_suspend(cs);
+ return;
+ }
+
+ /* CONN_STATE_LINGER[_*] fall through process_lingering_close() */
+ if (cs->pub.state >= CONN_STATE_LINGER) {
+ process_lingering_close(cs);
+ return;
+ }
+}
+
+/* conns_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) {
+ ap_log_error(APLOG_MARK, APLOG_TRACE1, 0, ap_server_conf,
+ "Stopping process due to MaxConnectionsPerChild");
+ signal_threads(ST_GRACEFUL);
+ }
+ else {
+ /* keep going */
+ conns_this_child = APR_INT32_MAX;
+ }
+}
+
+static int close_listeners(int *closed)
+{
+ ap_log_error(APLOG_MARK, APLOG_TRACE6, 0, ap_server_conf,
+ "clos%s listeners (connection_count=%u)",
+ *closed ? "ed" : "ing", apr_atomic_read32(&connection_count));
+ if (!*closed) {
+ int i;
+
+ ap_close_listeners_ex(my_bucket->listeners);
+ *closed = 1; /* once */
+
+ dying = 1;
+ ap_scoreboard_image->parent[ap_child_slot].quiescing = 1;
+ for (i = 0; i < threads_per_child; ++i) {
+ ap_update_child_status_from_indexes(ap_child_slot, i,
+ SERVER_GRACEFUL, NULL);
+ }
+ /* wake up the main thread */
+ kill(ap_my_pid, SIGTERM);
+
+ ap_queue_info_free_idle_pools(worker_queue_info);
+ ap_queue_interrupt_all(worker_queue);
+
+ return 1;
+ }
+ return 0;
+}
+
+static void unblock_signal(int sig)
+{
+ sigset_t sig_mask;
+
+ sigemptyset(&sig_mask);
+ sigaddset(&sig_mask, sig);
+#if defined(SIGPROCMASK_SETS_THREAD_MASK)
+ sigprocmask(SIG_UNBLOCK, &sig_mask, NULL);
+#else
+ pthread_sigmask(SIG_UNBLOCK, &sig_mask, NULL);
+#endif
+}
+
+static void dummy_signal_handler(int sig)
+{
+ /* XXX If specifying SIG_IGN is guaranteed to unblock a syscall,
+ * then we don't need this goofy function.
+ */
+}
+
+
+static apr_status_t push_timer2worker(timer_event_t* te)
+{
+ return ap_queue_push_timer(worker_queue, te);
+}
+
+/*
+ * Pre-condition: cs is neither in event_pollset nor a timeout queue
+ * this function may only be called by the listener
+ */
+static apr_status_t push2worker(event_conn_state_t *cs, apr_socket_t *csd,
+ apr_pool_t *ptrans)
+{
+ apr_status_t rc;
+
+ if (cs) {
+ csd = cs->pfd.desc.s;
+ ptrans = cs->p;
+ }
+ rc = ap_queue_push_socket(worker_queue, csd, cs, ptrans);
+ if (rc != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rc, ap_server_conf, APLOGNO(00471)
+ "push2worker: ap_queue_push_socket failed");
+ /* trash the connection; we couldn't queue the connected
+ * socket to a worker
+ */
+ if (cs) {
+ shutdown_connection(cs);
+ }
+ else {
+ if (csd) {
+ close_socket_nonblocking(csd);
+ }
+ if (ptrans) {
+ ap_queue_info_push_pool(worker_queue_info, ptrans);
+ }
+ }
+ signal_threads(ST_GRACEFUL);
+ }
+
+ 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 || APR_STATUS_IS_EOF(rc)) {
+ *have_idle_worker_p = 1;
+ }
+ else if (!blocking && rc == APR_EAGAIN) {
+ *all_busy = 1;
+ }
+ else {
+ 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);
+ }
+}
+
+/* Structures to reuse */
+static timer_event_t timer_free_ring;
+
+static apr_skiplist *timer_skiplist;
+static volatile apr_time_t timers_next_expiry;
+
+/* Same goal as for TIMEOUT_FUDGE_FACTOR (avoid extra poll calls), but applied
+ * to timers. Since their timeouts are custom (user defined), we can't be too
+ * approximative here (hence using 0.01s).
+ */
+#define EVENT_FUDGE_FACTOR apr_time_from_msec(10)
+
+/* The following compare function is used by apr_skiplist_insert() to keep the
+ * elements (timers) sorted and provide O(log n) complexity (this is also true
+ * for apr_skiplist_{find,remove}(), but those are not used in MPM event where
+ * inserted timers are not searched nor removed, but with apr_skiplist_pop()
+ * which does use any compare function). It is meant to return 0 when a == b,
+ * <0 when a < b, and >0 when a > b. However apr_skiplist_insert() will not
+ * add duplicates (i.e. a == b), and apr_skiplist_add() is only available in
+ * APR 1.6, yet multiple timers could possibly be created in the same micro-
+ * second (duplicates with regard to apr_time_t); therefore we implement the
+ * compare function to return +1 instead of 0 when compared timers are equal,
+ * thus duplicates are still added after each other (in order of insertion).
+ */
+static int timer_comp(void *a, void *b)
+{
+ apr_time_t t1 = (apr_time_t) ((timer_event_t *)a)->when;
+ apr_time_t t2 = (apr_time_t) ((timer_event_t *)b)->when;
+ AP_DEBUG_ASSERT(t1);
+ AP_DEBUG_ASSERT(t2);
+ return ((t1 < t2) ? -1 : 1);
+}
+
+static apr_thread_mutex_t *g_timer_skiplist_mtx;
+
+static apr_status_t event_register_timed_callback(apr_time_t t,
+ ap_mpm_callback_fn_t *cbfn,
+ void *baton)
+{
+ timer_event_t *te;
+ /* oh yeah, and make locking smarter/fine grained. */
+ apr_thread_mutex_lock(g_timer_skiplist_mtx);
+
+ if (!APR_RING_EMPTY(&timer_free_ring.link, timer_event_t, link)) {
+ te = APR_RING_FIRST(&timer_free_ring.link);
+ APR_RING_REMOVE(te, link);
+ }
+ else {
+ te = apr_skiplist_alloc(timer_skiplist, sizeof(timer_event_t));
+ APR_RING_ELEM_INIT(te, link);
+ }
+
+ te->cbfunc = cbfn;
+ te->baton = baton;
+ /* XXXXX: optimize */
+ te->when = t + apr_time_now();
+
+ {
+ apr_time_t next_expiry;
+
+ /* Okay, add sorted by when.. */
+ apr_skiplist_insert(timer_skiplist, te);
+
+ /* Cheaply update the global timers_next_expiry with this event's
+ * if it expires before.
+ */
+ next_expiry = timers_next_expiry;
+ if (!next_expiry || next_expiry > te->when + EVENT_FUDGE_FACTOR) {
+ timers_next_expiry = te->when;
+ /* Unblock the poll()ing listener for it to update its timeout. */
+ if (listener_is_wakeable) {
+ apr_pollset_wakeup(event_pollset);
+ }
+ }
+ }
+
+ apr_thread_mutex_unlock(g_timer_skiplist_mtx);
+
+ return APR_SUCCESS;
+}
+
+
+/*
+ * Flush data and close our side of the connection, then drain incoming data.
+ * If the latter would block put the connection in one of the linger timeout
+ * queues to be called back when ready, and repeat until it's closed by peer.
+ * Only to be called in the worker thread, and since it's in immediate call
+ * stack, we can afford a comfortable buffer size to consume data quickly.
+ * Pre-condition: cs is not in any timeout queue and not in the pollset,
+ * timeout_mutex is not locked
+ */
+#define LINGERING_BUF_SIZE (32 * 1024)
+static void process_lingering_close(event_conn_state_t *cs)
+{
+ apr_socket_t *csd = ap_get_conn_socket(cs->c);
+ char dummybuf[LINGERING_BUF_SIZE];
+ apr_size_t nbytes;
+ apr_status_t rv;
+ struct timeout_queue *q;
+
+ ap_log_cerror(APLOG_MARK, APLOG_TRACE6, 0, cs->c,
+ "lingering close from state %i", (int)cs->pub.state);
+ AP_DEBUG_ASSERT(cs->pub.state >= CONN_STATE_LINGER);
+
+ if (cs->pub.state == CONN_STATE_LINGER) {
+ /* defer_lingering_close() may have bumped lingering_count already */
+ if (!cs->deferred_linger) {
+ apr_atomic_inc32(&lingering_count);
+ }
+
+ apr_socket_timeout_set(csd, apr_time_from_sec(SECONDS_TO_LINGER));
+ if (ap_start_lingering_close(cs->c)) {
+ notify_suspend(cs);
+ close_connection(cs);
+ return;
+ }
+
+ cs->queue_timestamp = apr_time_now();
+ /* Clear APR_INCOMPLETE_READ if it was ever set, we'll do the poll()
+ * at the listener only from now, if needed.
+ */
+ apr_socket_opt_set(csd, APR_INCOMPLETE_READ, 0);
+ /*
+ * 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->pub.state = CONN_STATE_LINGER_SHORT;
+ }
+ else {
+ cs->pub.state = CONN_STATE_LINGER_NORMAL;
+ }
+ notify_suspend(cs);
+ }
+
+ apr_socket_timeout_set(csd, 0);
+ do {
+ nbytes = sizeof(dummybuf);
+ rv = apr_socket_recv(csd, dummybuf, &nbytes);
+ } while (rv == APR_SUCCESS);
+
+ if (!APR_STATUS_IS_EAGAIN(rv)) {
+ close_connection(cs);
+ return;
+ }
+
+ /* (Re)queue the connection to come back when readable */
+ update_reqevents_from_sense(cs, CONN_SENSE_WANT_READ);
+ q = (cs->pub.state == CONN_STATE_LINGER_SHORT) ? short_linger_q : linger_q;
+ apr_thread_mutex_lock(timeout_mutex);
+ TO_QUEUE_APPEND(q, cs);
+ rv = apr_pollset_add(event_pollset, &cs->pfd);
+ if (rv != APR_SUCCESS && !APR_STATUS_IS_EEXIST(rv)) {
+ AP_DEBUG_ASSERT(0);
+ TO_QUEUE_REMOVE(q, cs);
+ apr_thread_mutex_unlock(timeout_mutex);
+ ap_log_error(APLOG_MARK, APLOG_ERR, rv, ap_server_conf, APLOGNO(03092)
+ "process_lingering_close: apr_pollset_add failure");
+ close_connection(cs);
+ signal_threads(ST_GRACEFUL);
+ return;
+ }
+ apr_thread_mutex_unlock(timeout_mutex);
+}
+
+/* call 'func' for all elements of 'q' above 'expiry'.
+ * 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 expiry,
+ int (*func)(event_conn_state_t *))
+{
+ apr_uint32_t total = 0, count;
+ event_conn_state_t *first, *cs, *last;
+ struct event_conn_state_t trash;
+ struct timeout_queue *qp;
+ apr_status_t rv;
+
+ if (!*q->total) {
+ return;
+ }
+
+ APR_RING_INIT(&trash.timeout_list, event_conn_state_t, timeout_list);
+ for (qp = q; qp; qp = qp->next) {
+ count = 0;
+ cs = first = last = APR_RING_FIRST(&qp->head);
+ while (cs != APR_RING_SENTINEL(&qp->head, event_conn_state_t,
+ timeout_list)) {
+ /* Trash the entry if:
+ * - no expiry was given (zero means all), or
+ * - it expired (according to the queue timeout), or
+ * - the system clock skewed in the past: no entry should be
+ * registered above the given expiry (~now) + the queue
+ * timeout, we won't keep any here (eg. for centuries).
+ *
+ * Otherwise stop, no following entry will match thanks to the
+ * single timeout per queue (entries are added to the end!).
+ * This allows maintenance in O(1).
+ */
+ if (expiry && cs->queue_timestamp + qp->timeout > expiry
+ && cs->queue_timestamp < expiry + qp->timeout) {
+ /* Since this is the next expiring entry of this queue, update
+ * the global queues_next_expiry if it's later than this one.
+ */
+ apr_time_t elem_expiry = cs->queue_timestamp + qp->timeout;
+ apr_time_t next_expiry = queues_next_expiry;
+ if (!next_expiry
+ || next_expiry > elem_expiry + TIMEOUT_FUDGE_FACTOR) {
+ queues_next_expiry = elem_expiry;
+ }
+ break;
+ }
+
+ last = cs;
+ rv = apr_pollset_remove(event_pollset, &cs->pfd);
+ if (rv != APR_SUCCESS && !APR_STATUS_IS_NOTFOUND(rv)) {
+ AP_DEBUG_ASSERT(0);
+ 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)
+ continue;
+
+ APR_RING_UNSPLICE(first, last, timeout_list);
+ APR_RING_SPLICE_TAIL(&trash.timeout_list, first, last, event_conn_state_t,
+ timeout_list);
+ AP_DEBUG_ASSERT(*q->total >= count && qp->count >= count);
+ *q->total -= count;
+ qp->count -= count;
+ total += count;
+ }
+ if (!total)
+ return;
+
+ apr_thread_mutex_unlock(timeout_mutex);
+ first = APR_RING_FIRST(&trash.timeout_list);
+ do {
+ cs = APR_RING_NEXT(first, timeout_list);
+ TO_QUEUE_ELEM_INIT(first);
+ func(first);
+ first = cs;
+ } while (--total);
+ apr_thread_mutex_lock(timeout_mutex);
+}
+
+static void process_keepalive_queue(apr_time_t expiry)
+{
+ /* If all workers are busy, we kill older keep-alive connections so
+ * that they may connect to another process.
+ */
+ if (!expiry && *keepalive_q->total) {
+ ap_log_error(APLOG_MARK, APLOG_TRACE1, 0, ap_server_conf,
+ "All workers are busy or dying, will shutdown %u "
+ "keep-alive connections", *keepalive_q->total);
+ }
+ process_timeout_queue(keepalive_q, expiry, shutdown_connection);
+}
+
+static void * APR_THREAD_FUNC listener_thread(apr_thread_t * thd, void *dummy)
+{
+ apr_status_t rc;
+ proc_info *ti = dummy;
+ int process_slot = ti->pslot;
+ struct process_score *ps = ap_get_scoreboard_process(process_slot);
+ int closed = 0;
+ int have_idle_worker = 0;
+ apr_time_t last_log;
+
+ last_log = apr_time_now();
+ free(ti);
+
+ /* Unblock the signal used to wake this thread up, and set a handler for
+ * it.
+ */
+ apr_signal(LISTENER_SIGNAL, dummy_signal_handler);
+ unblock_signal(LISTENER_SIGNAL);
+
+ for (;;) {
+ timer_event_t *te;
+ const apr_pollfd_t *out_pfd;
+ apr_int32_t num = 0;
+ apr_interval_time_t timeout;
+ apr_time_t now, expiry = -1;
+ int workers_were_busy = 0;
+
+ if (conns_this_child <= 0)
+ check_infinite_requests();
+
+ if (listener_may_exit) {
+ int first_close = close_listeners(&closed);
+
+ if (terminate_mode == ST_UNGRACEFUL
+ || apr_atomic_read32(&connection_count) == 0)
+ break;
+
+ /* Don't wait in poll() for the first close (i.e. dying now), we
+ * want to maintain the queues and schedule defer_linger_chain ASAP
+ * to kill kept-alive connection and shutdown the workers and child
+ * faster.
+ */
+ if (first_close) {
+ goto do_maintenance; /* with expiry == -1 */
+ }
+ }
+
+ now = apr_time_now();
+ if (APLOGtrace6(ap_server_conf)) {
+ /* trace log status every second */
+ if (now - last_log > apr_time_from_sec(1)) {
+ last_log = now;
+ apr_thread_mutex_lock(timeout_mutex);
+ ap_log_error(APLOG_MARK, APLOG_TRACE6, 0, ap_server_conf,
+ "connections: %u (clogged: %u write-completion: %d "
+ "keep-alive: %d lingering: %d suspended: %u)",
+ apr_atomic_read32(&connection_count),
+ apr_atomic_read32(&clogged_count),
+ apr_atomic_read32(write_completion_q->total),
+ apr_atomic_read32(keepalive_q->total),
+ apr_atomic_read32(&lingering_count),
+ apr_atomic_read32(&suspended_count));
+ if (dying) {
+ ap_log_error(APLOG_MARK, APLOG_TRACE6, 0, ap_server_conf,
+ "%u/%u workers shutdown",
+ apr_atomic_read32(&threads_shutdown),
+ threads_per_child);
+ }
+ apr_thread_mutex_unlock(timeout_mutex);
+ }
+ }
+
+ /* Start with an infinite poll() timeout and update it according to
+ * the next expiring timer or queue entry. If there are none, either
+ * the listener is wakeable and it can poll() indefinitely until a wake
+ * up occurs, otherwise periodic checks (maintenance, shutdown, ...)
+ * must be performed.
+ */
+ now = apr_time_now();
+ timeout = -1;
+
+ /* Push expired timers to a worker, the first remaining one determines
+ * the maximum time to poll() below, if any.
+ */
+ expiry = timers_next_expiry;
+ if (expiry && expiry < now) {
+ apr_thread_mutex_lock(g_timer_skiplist_mtx);
+ while ((te = apr_skiplist_peek(timer_skiplist))) {
+ if (te->when > now) {
+ timers_next_expiry = te->when;
+ timeout = te->when - now;
+ break;
+ }
+ apr_skiplist_pop(timer_skiplist, NULL);
+ push_timer2worker(te);
+ }
+ if (!te) {
+ timers_next_expiry = 0;
+ }
+ apr_thread_mutex_unlock(g_timer_skiplist_mtx);
+ }
+
+ /* Same for queues, use their next expiry, if any. */
+ expiry = queues_next_expiry;
+ if (expiry
+ && (timeout < 0
+ || expiry <= now
+ || timeout > expiry - now)) {
+ timeout = expiry > now ? expiry - now : 0;
+ }
+
+ /* When non-wakeable, don't wait more than 100 ms, in any case. */
+#define NON_WAKEABLE_POLL_TIMEOUT apr_time_from_msec(100)
+ if (!listener_is_wakeable
+ && (timeout < 0
+ || timeout > NON_WAKEABLE_POLL_TIMEOUT)) {
+ timeout = NON_WAKEABLE_POLL_TIMEOUT;
+ }
+ else if (timeout > 0) {
+ /* apr_pollset_poll() might round down the timeout to milliseconds,
+ * let's forcibly round up here to never return before the timeout.
+ */
+ timeout = apr_time_from_msec(
+ apr_time_as_msec(timeout + apr_time_from_msec(1) - 1)
+ );
+ }
+
+ ap_log_error(APLOG_MARK, APLOG_TRACE7, 0, ap_server_conf,
+ "polling with timeout=%" APR_TIME_T_FMT
+ " queues_timeout=%" APR_TIME_T_FMT
+ " timers_timeout=%" APR_TIME_T_FMT,
+ timeout, queues_next_expiry - now,
+ timers_next_expiry - now);
+
+ rc = apr_pollset_poll(event_pollset, timeout, &num, &out_pfd);
+ if (rc != APR_SUCCESS) {
+ if (!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);
+ }
+ num = 0;
+ }
+
+ if (APLOGtrace7(ap_server_conf)) {
+ now = apr_time_now();
+ ap_log_error(APLOG_MARK, APLOG_TRACE7, rc, ap_server_conf,
+ "polled with num=%u exit=%d/%d conns=%d"
+ " queues_timeout=%" APR_TIME_T_FMT
+ " timers_timeout=%" APR_TIME_T_FMT,
+ num, listener_may_exit, dying,
+ apr_atomic_read32(&connection_count),
+ queues_next_expiry - now, timers_next_expiry - now);
+ }
+
+ /* XXX possible optimization: stash the current time for use as
+ * r->request_time for new requests or queues maintenance
+ */
+
+ for (; num; --num, ++out_pfd) {
+ listener_poll_type *pt = (listener_poll_type *) out_pfd->client_data;
+ if (pt->type == PT_CSD) {
+ /* one of the sockets is readable */
+ event_conn_state_t *cs = (event_conn_state_t *) pt->baton;
+ struct timeout_queue *remove_from_q = NULL;
+ /* don't wait for a worker for a keepalive request or
+ * lingering close processing. */
+ int blocking = 0;
+
+ switch (cs->pub.state) {
+ case CONN_STATE_WRITE_COMPLETION:
+ remove_from_q = cs->sc->wc_q;
+ blocking = 1;
+ break;
+
+ case CONN_STATE_CHECK_REQUEST_LINE_READABLE:
+ cs->pub.state = CONN_STATE_READ_REQUEST_LINE;
+ remove_from_q = cs->sc->ka_q;
+ break;
+
+ case CONN_STATE_LINGER_NORMAL:
+ remove_from_q = linger_q;
+ break;
+
+ case CONN_STATE_LINGER_SHORT:
+ remove_from_q = short_linger_q;
+ break;
+
+ default:
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rc,
+ ap_server_conf, APLOGNO(03096)
+ "event_loop: unexpected state %d",
+ cs->pub.state);
+ ap_assert(0);
+ }
+
+ if (remove_from_q) {
+ apr_thread_mutex_lock(timeout_mutex);
+ TO_QUEUE_REMOVE(remove_from_q, cs);
+ rc = apr_pollset_remove(event_pollset, &cs->pfd);
+ apr_thread_mutex_unlock(timeout_mutex);
+ /*
+ * 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_DEBUG_ASSERT(0);
+ ap_log_error(APLOG_MARK, APLOG_ERR, rc, ap_server_conf,
+ APLOGNO(03094) "pollset remove failed");
+ close_connection(cs);
+ signal_threads(ST_GRACEFUL);
+ break;
+ }
+
+ /* If we don't get a worker immediately (nonblocking), we
+ * close the connection; the client can re-connect to a
+ * different process for keepalive, and for lingering close
+ * the connection will be shutdown so the choice is to favor
+ * incoming/alive connections.
+ */
+ get_worker(&have_idle_worker, blocking,
+ &workers_were_busy);
+ if (!have_idle_worker) {
+ shutdown_connection(cs);
+ }
+ else if (push2worker(cs, NULL, NULL) == APR_SUCCESS) {
+ have_idle_worker = 0;
+ }
+ }
+ }
+ else if (pt->type == PT_ACCEPT && !listeners_disabled()) {
+ /* A Listener Socket is ready for an accept() */
+ if (workers_were_busy) {
+ disable_listensocks();
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf,
+ "All workers busy, not accepting new conns "
+ "in this process");
+ }
+ else if (connections_above_limit(&workers_were_busy)) {
+ disable_listensocks();
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf,
+ "Too many open connections (%u), "
+ "not accepting new conns in this process",
+ apr_atomic_read32(&connection_count));
+ ap_log_error(APLOG_MARK, APLOG_TRACE1, 0, ap_server_conf,
+ "Idle workers: %u",
+ ap_queue_info_num_idlers(worker_queue_info));
+ }
+ else if (!listener_may_exit) {
+ void *csd = NULL;
+ ap_listen_rec *lr = (ap_listen_rec *) pt->baton;
+ apr_pool_t *ptrans; /* Pool for per-transaction stuff */
+ ap_queue_info_pop_pool(worker_queue_info, &ptrans);
+
+ if (ptrans == NULL) {
+ /* create a new transaction pool for each accepted socket */
+ apr_allocator_t *allocator = NULL;
+
+ rc = apr_allocator_create(&allocator);
+ if (rc == APR_SUCCESS) {
+ apr_allocator_max_free_set(allocator,
+ ap_max_mem_free);
+ rc = apr_pool_create_ex(&ptrans, pconf, NULL,
+ allocator);
+ if (rc == APR_SUCCESS) {
+ apr_pool_tag(ptrans, "transaction");
+ apr_allocator_owner_set(allocator, ptrans);
+ }
+ }
+ if (rc != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rc,
+ ap_server_conf, APLOGNO(03097)
+ "Failed to create transaction pool");
+ if (allocator) {
+ apr_allocator_destroy(allocator);
+ }
+ resource_shortage = 1;
+ signal_threads(ST_GRACEFUL);
+ continue;
+ }
+ }
+
+ 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) {
+ conns_this_child--;
+ if (push2worker(NULL, csd, ptrans) == APR_SUCCESS) {
+ have_idle_worker = 0;
+ }
+ }
+ else {
+ ap_queue_info_push_pool(worker_queue_info, ptrans);
+ }
+ }
+ } /* if:else on pt->type */
+ } /* for processing poll */
+
+ /* We process the timeout queues here only when the global
+ * queues_next_expiry is passed. This happens accurately since
+ * adding to the queues (in workers) can only decrease this expiry,
+ * while latest ones are only taken into account here (in listener)
+ * during queues' processing, with the lock held. This works both
+ * with and without wake-ability.
+ */
+ expiry = queues_next_expiry;
+do_maintenance:
+ if (expiry && expiry < (now = apr_time_now())) {
+ ap_log_error(APLOG_MARK, APLOG_TRACE7, 0, ap_server_conf,
+ "queues maintenance with timeout=%" APR_TIME_T_FMT,
+ expiry > 0 ? expiry - now : -1);
+ apr_thread_mutex_lock(timeout_mutex);
+
+ /* Steps below will recompute this. */
+ queues_next_expiry = 0;
+
+ /* Step 1: keepalive timeouts */
+ if (workers_were_busy || dying) {
+ process_keepalive_queue(0); /* kill'em all \m/ */
+ }
+ else {
+ process_keepalive_queue(now);
+ }
+ /* Step 2: write completion timeouts */
+ process_timeout_queue(write_completion_q, now,
+ defer_lingering_close);
+ /* Step 3: (normal) lingering close completion timeouts */
+ if (dying && linger_q->timeout > short_linger_q->timeout) {
+ /* Dying, force short timeout for normal lingering close */
+ linger_q->timeout = short_linger_q->timeout;
+ }
+ process_timeout_queue(linger_q, now, shutdown_connection);
+ /* Step 4: (short) lingering close completion timeouts */
+ process_timeout_queue(short_linger_q, now, shutdown_connection);
+
+ apr_thread_mutex_unlock(timeout_mutex);
+ ap_log_error(APLOG_MARK, APLOG_TRACE7, 0, ap_server_conf,
+ "queues maintained with timeout=%" APR_TIME_T_FMT,
+ queues_next_expiry > now ? queues_next_expiry - now
+ : -1);
+
+ ps->keep_alive = apr_atomic_read32(keepalive_q->total);
+ ps->write_completion = apr_atomic_read32(write_completion_q->total);
+ ps->connections = apr_atomic_read32(&connection_count);
+ ps->suspended = apr_atomic_read32(&suspended_count);
+ ps->lingering_close = apr_atomic_read32(&lingering_count);
+ }
+ else if ((workers_were_busy || dying)
+ && apr_atomic_read32(keepalive_q->total)) {
+ apr_thread_mutex_lock(timeout_mutex);
+ process_keepalive_queue(0); /* kill'em all \m/ */
+ apr_thread_mutex_unlock(timeout_mutex);
+ ps->keep_alive = 0;
+ }
+
+ /* If there are some lingering closes to defer (to a worker), schedule
+ * them now. We might wakeup a worker spuriously if another one empties
+ * defer_linger_chain in the meantime, but there also may be no active
+ * or all busy workers for an undefined time. In any case a deferred
+ * lingering close can't starve if we do that here since the chain is
+ * filled only above in the listener and it's emptied only in the
+ * worker(s); thus a NULL here means it will stay so while the listener
+ * waits (possibly indefinitely) in poll().
+ */
+ if (defer_linger_chain) {
+ get_worker(&have_idle_worker, 0, &workers_were_busy);
+ if (have_idle_worker
+ && defer_linger_chain /* re-test */
+ && push2worker(NULL, NULL, NULL) == APR_SUCCESS) {
+ have_idle_worker = 0;
+ }
+ }
+
+ if (!workers_were_busy && should_enable_listensocks()) {
+ enable_listensocks();
+ }
+ } /* listener main loop */
+
+ ap_queue_term(worker_queue);
+
+ apr_thread_exit(thd, APR_SUCCESS);
+ return NULL;
+}
+
+/*
+ * During graceful shutdown, if there are more running worker threads than
+ * open connections, exit one worker thread.
+ *
+ * return 1 if thread should exit, 0 if it should continue running.
+ */
+static int worker_thread_should_exit_early(void)
+{
+ for (;;) {
+ apr_uint32_t conns = apr_atomic_read32(&connection_count);
+ apr_uint32_t dead = apr_atomic_read32(&threads_shutdown);
+ apr_uint32_t newdead;
+
+ AP_DEBUG_ASSERT(dead <= threads_per_child);
+ if (conns >= threads_per_child - dead)
+ return 0;
+
+ newdead = dead + 1;
+ if (apr_atomic_cas32(&threads_shutdown, newdead, dead) == dead) {
+ /*
+ * No other thread has exited in the mean time, safe to exit
+ * this one.
+ */
+ return 1;
+ }
+ }
+}
+
+/* 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->pslot;
+ int thread_slot = ti->tslot;
+ apr_status_t rv;
+ int is_idle = 0;
+
+ 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->mpm->my_generation;
+ ap_update_child_status_from_indexes(process_slot, thread_slot,
+ SERVER_STARTING, NULL);
+
+ for (;;) {
+ apr_socket_t *csd = NULL;
+ event_conn_state_t *cs;
+ timer_event_t *te = NULL;
+ apr_pool_t *ptrans; /* Pool for per-transaction stuff */
+
+ 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;
+ }
+ /* A new idler may have changed connections_above_limit(),
+ * let the listener know and decide.
+ */
+ if (listener_is_wakeable && should_enable_listensocks()) {
+ apr_pollset_wakeup(event_pollset);
+ }
+ 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;
+ }
+ if (dying && worker_thread_should_exit_early()) {
+ break;
+ }
+
+ rv = ap_queue_pop_something(worker_queue, &csd, (void **)&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,
+ APLOGNO(03099) "ap_queue_pop_socket failed");
+ }
+ continue;
+ }
+ if (te != NULL) {
+ te->cbfunc(te->baton);
+
+ {
+ apr_thread_mutex_lock(g_timer_skiplist_mtx);
+ APR_RING_INSERT_TAIL(&timer_free_ring.link, te, timer_event_t, link);
+ apr_thread_mutex_unlock(g_timer_skiplist_mtx);
+ }
+ }
+ else {
+ is_idle = 0;
+ if (csd != NULL) {
+ worker_sockets[thread_slot] = csd;
+ process_socket(thd, ptrans, csd, cs, process_slot, thread_slot);
+ worker_sockets[thread_slot] = NULL;
+ }
+ }
+
+ /* If there are deferred lingering closes, handle them now. */
+ while (!workers_may_exit) {
+ cs = defer_linger_chain;
+ if (!cs) {
+ break;
+ }
+ if (apr_atomic_casptr((void *)&defer_linger_chain, cs->chain,
+ cs) != cs) {
+ /* Race lost, try again */
+ continue;
+ }
+ cs->chain = NULL;
+ AP_DEBUG_ASSERT(cs->pub.state == CONN_STATE_LINGER);
+
+ worker_sockets[thread_slot] = csd = cs->pfd.desc.s;
+ process_socket(thd, cs->p, csd, cs, process_slot, thread_slot);
+ worker_sockets[thread_slot] = NULL;
+ }
+ }
+
+ ap_update_child_status_from_indexes(process_slot, thread_slot,
+ dying ? SERVER_DEAD
+ : SERVER_GRACEFUL, 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->pslot = my_child_num;
+ my_info->tslot = -1; /* listener thread doesn't have a thread slot */
+ rv = ap_thread_create(&ts->listener, thread_attr, listener_thread,
+ my_info, pruntime);
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_ALERT, rv, ap_server_conf, APLOGNO(00474)
+ "ap_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);
+}
+
+static void setup_threads_runtime(void)
+{
+ apr_status_t rv;
+ ap_listen_rec *lr;
+ apr_pool_t *pskip = NULL;
+ int max_recycled_pools = -1, i;
+ const int good_methods[] = { APR_POLLSET_KQUEUE,
+ APR_POLLSET_PORT,
+ APR_POLLSET_EPOLL };
+ /* XXX: K-A or lingering close connection included in the async factor */
+ const apr_uint32_t async_factor = worker_factor / WORKER_FACTOR_SCALE;
+ const apr_uint32_t pollset_size = (apr_uint32_t)num_listensocks +
+ (apr_uint32_t)threads_per_child *
+ (async_factor > 2 ? async_factor : 2);
+ int pollset_flags;
+
+ /* Event's skiplist operations will happen concurrently with other modules'
+ * runtime so they need their own pool for allocations, and its lifetime
+ * should be at least the one of the connections (ptrans). Thus pskip is
+ * created as a subpool of pconf like/before ptrans (before so that it's
+ * destroyed after). In forked mode pconf is never destroyed so we are good
+ * anyway, but in ONE_PROCESS mode this ensures that the skiplist works
+ * from connection/ptrans cleanups (even after pchild is destroyed).
+ */
+ apr_pool_create(&pskip, pconf);
+ apr_pool_tag(pskip, "mpm_skiplist");
+ apr_thread_mutex_create(&g_timer_skiplist_mtx, APR_THREAD_MUTEX_DEFAULT, pskip);
+ APR_RING_INIT(&timer_free_ring.link, timer_event_t, link);
+ apr_skiplist_init(&timer_skiplist, pskip);
+ apr_skiplist_set_compare(timer_skiplist, timer_comp, timer_comp);
+
+ /* All threads (listener, workers) and synchronization objects (queues,
+ * pollset, mutexes...) created here should have at least the lifetime of
+ * the connections they handle (i.e. ptrans). We can't use this thread's
+ * self pool because all these objects survive it, nor use pchild or pconf
+ * directly because this starter thread races with other modules' runtime,
+ * nor finally pchild (or subpool thereof) because it is killed explicitly
+ * before pconf (thus connections/ptrans can live longer, which matters in
+ * ONE_PROCESS mode). So this leaves us with a subpool of pconf, created
+ * before any ptrans hence destroyed after.
+ */
+ apr_pool_create(&pruntime, pconf);
+ apr_pool_tag(pruntime, "mpm_runtime");
+
+ /* We must create the fd queues before we start up the listener
+ * and worker threads. */
+ rv = ap_queue_create(&worker_queue, threads_per_child, pruntime);
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_ALERT, rv, ap_server_conf, APLOGNO(03100)
+ "ap_queue_create() 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, pruntime,
+ threads_per_child, max_recycled_pools);
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_ALERT, rv, ap_server_conf, APLOGNO(03101)
+ "ap_queue_info_create() failed");
+ clean_child_exit(APEXIT_CHILDFATAL);
+ }
+
+ /* Create the timeout mutex and main pollset before the listener
+ * thread starts.
+ */
+ rv = apr_thread_mutex_create(&timeout_mutex, APR_THREAD_MUTEX_DEFAULT,
+ pruntime);
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_ERR, rv, ap_server_conf, APLOGNO(03102)
+ "creation of the timeout mutex failed.");
+ clean_child_exit(APEXIT_CHILDFATAL);
+ }
+
+ /* Create the main pollset */
+ pollset_flags = APR_POLLSET_THREADSAFE | APR_POLLSET_NOCOPY |
+ APR_POLLSET_NODEFAULT | APR_POLLSET_WAKEABLE;
+ for (i = 0; i < sizeof(good_methods) / sizeof(good_methods[0]); i++) {
+ rv = apr_pollset_create_ex(&event_pollset, pollset_size, pruntime,
+ pollset_flags, good_methods[i]);
+ if (rv == APR_SUCCESS) {
+ listener_is_wakeable = 1;
+ break;
+ }
+ }
+ if (rv != APR_SUCCESS) {
+ pollset_flags &= ~APR_POLLSET_WAKEABLE;
+ for (i = 0; i < sizeof(good_methods) / sizeof(good_methods[0]); i++) {
+ rv = apr_pollset_create_ex(&event_pollset, pollset_size, pruntime,
+ pollset_flags, good_methods[i]);
+ if (rv == APR_SUCCESS) {
+ break;
+ }
+ }
+ }
+ if (rv != APR_SUCCESS) {
+ pollset_flags &= ~APR_POLLSET_NODEFAULT;
+ rv = apr_pollset_create(&event_pollset, pollset_size, pruntime,
+ pollset_flags);
+ }
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_ERR, rv, ap_server_conf, APLOGNO(03103)
+ "apr_pollset_create with Thread Safety failed.");
+ clean_child_exit(APEXIT_CHILDFATAL);
+ }
+
+ /* Add listeners to the main pollset */
+ listener_pollfd = apr_pcalloc(pruntime, num_listensocks *
+ sizeof(apr_pollfd_t));
+ for (i = 0, lr = my_bucket->listeners; lr; lr = lr->next, i++) {
+ apr_pollfd_t *pfd;
+ listener_poll_type *pt;
+
+ AP_DEBUG_ASSERT(i < num_listensocks);
+ pfd = &listener_pollfd[i];
+
+ pfd->reqevents = APR_POLLIN | APR_POLLHUP | APR_POLLERR;
+ pfd->desc_type = APR_POLL_SOCKET;
+ pfd->desc.s = lr->sd;
+
+ pt = apr_pcalloc(pruntime, sizeof(*pt));
+ pfd->client_data = pt;
+ pt->type = PT_ACCEPT;
+ pt->baton = lr;
+
+ apr_socket_opt_set(pfd->desc.s, APR_SO_NONBLOCK, 1);
+ apr_pollset_add(event_pollset, pfd);
+
+ lr->accept_func = ap_unixd_accept;
+ }
+
+ worker_sockets = apr_pcalloc(pruntime, threads_per_child *
+ sizeof(apr_socket_t *));
+}
+
+/* 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 my_child_num = ts->child_num_arg;
+ proc_info *my_info;
+ apr_status_t rv;
+ int threads_created = 0;
+ int listener_started = 0;
+ int prev_threads_created;
+ int loops, i;
+
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, APLOGNO(02471)
+ "start_threads: Using %s (%swakeable)",
+ apr_pollset_method_name(event_pollset),
+ listener_is_wakeable ? "" : "not ");
+
+ 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[my_child_num][i].status;
+
+ if (status != SERVER_DEAD) {
+ continue;
+ }
+
+ my_info = (proc_info *) ap_malloc(sizeof(proc_info));
+ my_info->pslot = my_child_num;
+ my_info->tslot = i;
+
+ /* 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 = ap_thread_create(&threads[i], thread_attr,
+ worker_thread, my_info, pruntime);
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_ALERT, rv, ap_server_conf,
+ APLOGNO(03104)
+ "ap_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 (!dying) {
+ apr_sleep(apr_time_from_msec(500));
+ if (dying || ++iter > 10) {
+ break;
+ }
+ /* listener has not stopped accepting yet */
+ ap_log_error(APLOG_MARK, APLOG_TRACE1, 0, ap_server_conf,
+ "listener has not stopped accepting yet (%d iter)", iter);
+ wakeup_listener();
+ }
+ 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 child_main(int child_num_arg, int child_bucket)
+{
+ apr_thread_t **threads;
+ apr_status_t rv;
+ thread_starter *ts;
+ apr_threadattr_t *thread_attr;
+ apr_thread_t *start_thread_id;
+ int i;
+
+ /* for benefit of any hooks that run as this child initializes */
+ retained->mpm->mpm_state = AP_MPMQ_STARTING;
+
+ ap_my_pid = getpid();
+ ap_child_slot = child_num_arg;
+ ap_fatal_signal_child_setup(ap_server_conf);
+
+ /* Get a sub context for global allocations in this child, so that
+ * we can have cleanups occur when the child exits.
+ */
+ apr_pool_create(&pchild, pconf);
+ apr_pool_tag(pchild, "pchild");
+
+#if AP_HAS_THREAD_LOCAL
+ if (!one_process) {
+ apr_thread_t *thd = NULL;
+ if ((rv = ap_thread_main_create(&thd, pchild))) {
+ ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf, APLOGNO(10377)
+ "Couldn't initialize child main thread");
+ clean_child_exit(APEXIT_CHILDFATAL);
+ }
+ }
+#endif
+
+ /* close unused listeners and pods */
+ for (i = 0; i < retained->mpm->num_buckets; i++) {
+ if (i != child_bucket) {
+ ap_close_listeners_ex(all_buckets[i].listeners);
+ ap_mpm_podx_close(all_buckets[i].pod);
+ }
+ }
+
+ /*stuff to do before we switch id's, so we have permissions. */
+ ap_reopen_scoreboard(pchild, NULL, 0);
+
+ /* done with init critical section */
+ if (ap_run_drop_privileges(pchild, ap_server_conf)) {
+ clean_child_exit(APEXIT_CHILDFATAL);
+ }
+
+ /* 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. Let's also do this before
+ * child_init() hooks are called and possibly create threads that
+ * otherwise could "steal" (implicitly) MPM's signals.
+ */
+ 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);
+ }
+
+ ap_run_child_init(pchild, ap_server_conf);
+
+ if (ap_max_requests_per_child) {
+ conns_this_child = ap_max_requests_per_child;
+ }
+ else {
+ /* coding a value of zero means infinity */
+ conns_this_child = APR_INT32_MAX;
+ }
+
+ /* Setup threads */
+
+ /* Globals used by signal_threads() so to be initialized before */
+ setup_threads_runtime();
+
+ /* 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) {
+ rv = apr_threadattr_stacksize_set(thread_attr, ap_thread_stacksize);
+ if (rv != APR_SUCCESS && rv != APR_ENOTIMPL) {
+ ap_log_error(APLOG_MARK, APLOG_WARNING, rv, ap_server_conf, APLOGNO(02436)
+ "WARNING: ThreadStackSize of %" APR_SIZE_T_FMT " is "
+ "inappropriate, using default",
+ ap_thread_stacksize);
+ }
+ }
+
+ ts->threads = threads;
+ ts->listener = NULL;
+ ts->child_num_arg = child_num_arg;
+ ts->threadattr = thread_attr;
+
+ rv = ap_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)
+ "ap_thread_create: unable to create worker thread");
+ /* let the parent decide how bad this really is */
+ clean_child_exit(APEXIT_CHILDSICK);
+ }
+
+ retained->mpm->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
+ */
+ apr_signal(SIGTERM, dummy_signal_handler);
+ unblock_signal(SIGTERM);
+ /* Watch for any messages from the parent over the POD */
+ while (1) {
+ rv = ap_mpm_podx_check(my_bucket->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).
+ */
+ ap_log_error(APLOG_MARK, APLOG_TRACE1, 0, ap_server_conf,
+ "%s termination received, joining workers",
+ rv == AP_MPM_PODX_GRACEFUL ? "graceful" : "ungraceful");
+ join_workers(ts->listener, threads);
+ ap_log_error(APLOG_MARK, APLOG_TRACE1, 0, ap_server_conf,
+ "%s termination, workers joined, exiting",
+ rv == AP_MPM_PODX_GRACEFUL ? "graceful" : "ungraceful");
+ }
+
+ free(threads);
+
+ clean_child_exit(resource_shortage ? APEXIT_CHILDSICK : 0);
+}
+
+static int make_child(server_rec * s, int slot, int bucket)
+{
+ int pid;
+
+ if (slot + 1 > retained->max_daemon_used) {
+ retained->max_daemon_used = slot + 1;
+ }
+
+ if (ap_scoreboard_image->parent[slot].pid != 0) {
+ /* XXX replace with assert or remove ? */
+ ap_log_error(APLOG_MARK, APLOG_ERR, 0, ap_server_conf, APLOGNO(03455)
+ "BUG: Scoreboard slot %d should be empty but is "
+ "in use by pid %" APR_PID_T_FMT,
+ slot, ap_scoreboard_image->parent[slot].pid);
+ return -1;
+ }
+
+ if (one_process) {
+ my_bucket = &all_buckets[0];
+
+ event_note_child_started(slot, getpid());
+ child_main(slot, 0);
+ /* NOTREACHED */
+ ap_assert(0);
+ return -1;
+ }
+
+ 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) {
+#if AP_HAS_THREAD_LOCAL
+ ap_thread_current_after_fork();
+#endif
+
+ my_bucket = &all_buckets[bucket];
+
+#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, bucket);
+ /* NOTREACHED */
+ ap_assert(0);
+ return -1;
+ }
+
+ 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 < server_limit; ++i) {
+ if (ap_scoreboard_image->parent[i].pid != 0) {
+ continue;
+ }
+ if (make_child(ap_server_conf, i, i % retained->mpm->num_buckets) < 0) {
+ break;
+ }
+ --number_to_start;
+ }
+}
+
+static void perform_idle_server_maintenance(int child_bucket,
+ int *max_daemon_used)
+{
+ int num_buckets = retained->mpm->num_buckets;
+ int idle_thread_count = 0;
+ process_score *ps;
+ int free_length = 0;
+ int free_slots[MAX_SPAWN_RATE];
+ int last_non_dead = -1;
+ int active_thread_count = 0;
+ int i, j;
+
+ for (i = 0; i < server_limit; ++i) {
+ if (num_buckets > 1 && (i % num_buckets) != child_bucket) {
+ /* We only care about child_bucket in this call */
+ continue;
+ }
+ if (i >= retained->max_daemon_used &&
+ free_length == retained->idle_spawn_rate[child_bucket]) {
+ /* short cut if all active processes have been examined and
+ * enough empty scoreboard slots have been found
+ */
+ break;
+ }
+
+ ps = &ap_scoreboard_image->parent[i];
+ if (ps->pid != 0) {
+ int child_threads_active = 0;
+ if (ps->quiescing == 1) {
+ ps->quiescing = 2;
+ retained->active_daemons--;
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf,
+ "Child %d quiescing: pid %d, gen %d, "
+ "active %d/%d, total %d/%d/%d",
+ i, (int)ps->pid, (int)ps->generation,
+ retained->active_daemons, active_daemons_limit,
+ retained->total_daemons, retained->max_daemon_used,
+ server_limit);
+ }
+ for (j = 0; j < threads_per_child; j++) {
+ int status = ap_scoreboard_image->servers[i][j].status;
+
+ /* We consider a starting server as idle because we started it
+ * at least a cycle ago, and if it still hasn't finished starting
+ * then we're just going to swamp things worse by forking more.
+ * So we hopefully won't need to fork more if we count it.
+ * This depends on the ordering of SERVER_READY and SERVER_STARTING.
+ */
+ if (status <= SERVER_READY && !ps->quiescing && !ps->not_accepting
+ && ps->generation == retained->mpm->my_generation) {
+ ++idle_thread_count;
+ }
+ if (status >= SERVER_READY && status < SERVER_GRACEFUL) {
+ ++child_threads_active;
+ }
+ }
+ active_thread_count += child_threads_active;
+ if (child_threads_active == threads_per_child) {
+ had_healthy_child = 1;
+ }
+ last_non_dead = i;
+ }
+ else if (free_length < retained->idle_spawn_rate[child_bucket]) {
+ free_slots[free_length++] = i;
+ }
+ }
+ if (*max_daemon_used < last_non_dead + 1) {
+ *max_daemon_used = last_non_dead + 1;
+ }
+
+ if (retained->sick_child_detected) {
+ if (had_healthy_child) {
+ /* Assume this is a transient error, even though it may not be. Leave
+ * the server up in case it is able to serve some requests or the
+ * problem will be resolved.
+ */
+ retained->sick_child_detected = 0;
+ }
+ else if (child_bucket < num_buckets - 1) {
+ /* check for had_healthy_child up to the last child bucket */
+ return;
+ }
+ else {
+ /* looks like a basket case, as no child ever fully initialized; give up.
+ */
+ retained->mpm->shutdown_pending = 1;
+ child_fatal = 1;
+ ap_log_error(APLOG_MARK, APLOG_ALERT, 0,
+ ap_server_conf, APLOGNO(02324)
+ "A resource shortage or other unrecoverable failure "
+ "was encountered before any child process initialized "
+ "successfully... httpd is exiting!");
+ /* the child already logged the failure details */
+ return;
+ }
+ }
+
+ AP_DEBUG_ASSERT(retained->active_daemons <= retained->total_daemons
+ && retained->total_daemons <= retained->max_daemon_used
+ && retained->max_daemon_used <= server_limit);
+
+ if (idle_thread_count > max_spare_threads / num_buckets) {
+ /*
+ * Child processes that we ask to shut down won't die immediately
+ * but may stay around for a long time when they finish their
+ * requests. If the server load changes many times, many such
+ * gracefully finishing processes may accumulate, filling up the
+ * scoreboard. To avoid running out of scoreboard entries, we
+ * don't shut down more processes if there are stopping ones
+ * already (i.e. active_daemons != total_daemons) and not enough
+ * slack space in the scoreboard for a graceful restart.
+ *
+ * XXX It would be nice if we could
+ * XXX - kill processes without keepalive connections first
+ * XXX - tell children to stop accepting new connections, and
+ * XXX depending on server load, later be able to resurrect them
+ * or kill them
+ */
+ int do_kill = (retained->active_daemons == retained->total_daemons
+ || (server_limit - retained->total_daemons >
+ active_daemons_limit));
+ ap_log_error(APLOG_MARK, APLOG_TRACE5, 0, ap_server_conf,
+ "%shutting down one child: "
+ "active %d/%d, total %d/%d/%d, "
+ "idle threads %d, max workers %d",
+ (do_kill) ? "S" : "Not s",
+ retained->active_daemons, active_daemons_limit,
+ retained->total_daemons, retained->max_daemon_used,
+ server_limit, idle_thread_count, max_workers);
+ if (do_kill) {
+ ap_mpm_podx_signal(all_buckets[child_bucket].pod,
+ AP_MPM_PODX_GRACEFUL);
+ }
+ else {
+ /* Wait for dying daemon(s) to exit */
+ }
+ retained->idle_spawn_rate[child_bucket] = 1;
+ }
+ else if (idle_thread_count < min_spare_threads / num_buckets) {
+ if (active_thread_count >= max_workers / num_buckets) {
+ if (0 == idle_thread_count) {
+ if (!retained->maxclients_reported) {
+ 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 {
+ if (!retained->near_maxclients_reported) {
+ ap_log_error(APLOG_MARK, APLOG_ERR, 0, ap_server_conf, APLOGNO(10159)
+ "server is within MinSpareThreads of "
+ "MaxRequestWorkers, consider raising the "
+ "MaxRequestWorkers setting");
+ retained->near_maxclients_reported = 1;
+ }
+ }
+ retained->idle_spawn_rate[child_bucket] = 1;
+ }
+ else if (free_length == 0) { /* scoreboard is full, can't fork */
+ ap_log_error(APLOG_MARK, APLOG_ERR, 0, ap_server_conf, APLOGNO(03490)
+ "scoreboard is full, not at MaxRequestWorkers."
+ "Increase ServerLimit.");
+ retained->idle_spawn_rate[child_bucket] = 1;
+ }
+ else {
+ if (free_length > retained->idle_spawn_rate[child_bucket]) {
+ free_length = retained->idle_spawn_rate[child_bucket];
+ }
+ if (free_length + retained->active_daemons > active_daemons_limit) {
+ if (retained->active_daemons < active_daemons_limit) {
+ free_length = active_daemons_limit - retained->active_daemons;
+ }
+ else {
+ ap_log_error(APLOG_MARK, APLOG_TRACE1, 0, ap_server_conf,
+ "server is at active daemons limit, spawning "
+ "of %d children cancelled: active %d/%d, "
+ "total %d/%d/%d, rate %d", free_length,
+ retained->active_daemons, active_daemons_limit,
+ retained->total_daemons, retained->max_daemon_used,
+ server_limit, retained->idle_spawn_rate[child_bucket]);
+ /* reset the spawning rate and prevent its growth below */
+ retained->idle_spawn_rate[child_bucket] = 1;
+ ++retained->hold_off_on_exponential_spawning;
+ free_length = 0;
+ }
+ }
+ if (retained->idle_spawn_rate[child_bucket] >= 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, %d active children, and %d children "
+ "that are shutting down", free_length,
+ idle_thread_count, retained->active_daemons,
+ retained->total_daemons);
+ }
+ for (i = 0; i < free_length; ++i) {
+ int slot = free_slots[i];
+ if (make_child(ap_server_conf, slot, child_bucket) < 0) {
+ continue;
+ }
+ if (*max_daemon_used < slot + 1) {
+ *max_daemon_used = slot + 1;
+ }
+ }
+ /* 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[child_bucket]
+ < MAX_SPAWN_RATE / num_buckets) {
+ retained->idle_spawn_rate[child_bucket] *= 2;
+ }
+ }
+ }
+ else {
+ retained->idle_spawn_rate[child_bucket] = 1;
+ }
+}
+
+static void server_main_loop(int remaining_children_to_start)
+{
+ int num_buckets = retained->mpm->num_buckets;
+ int max_daemon_used = 0;
+ int successive_kills = 0;
+ int child_slot;
+ apr_exit_why_e exitwhy;
+ int status, processed_status;
+ apr_proc_t pid;
+ int i;
+
+ while (!retained->mpm->restart_pending && !retained->mpm->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->mpm->my_generation) {
+ retained->mpm->shutdown_pending = 1;
+ child_fatal = 1;
+ /*
+ * total_daemons counting will be off now, but as we
+ * are shutting down, that is not an issue anymore.
+ */
+ 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) {
+ event_note_child_stopped(child_slot, 0, 0);
+
+ if (processed_status == APEXIT_CHILDSICK) {
+ /* resource shortage, minimize the fork rate */
+ retained->idle_spawn_rate[child_slot % num_buckets] = 1;
+ }
+ else if (remaining_children_to_start) {
+ /* we're still doing a 1-for-1 replacement of dead
+ * children with new children
+ */
+ make_child(ap_server_conf, child_slot,
+ child_slot % num_buckets);
+ --remaining_children_to_start;
+ }
+ }
+#if APR_HAS_OTHER_CHILD
+ else if (apr_proc_other_child_alert(&pid, APR_OC_REASON_DEATH,
+ status) == 0) {
+ /* handled */
+ }
+#endif
+ else if (retained->mpm->was_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. If a child is
+ * killed by a signal (faulting) we want to restart it ASAP
+ * though, up to 3 successive faults or we stop this until
+ * a timeout happens again (to avoid the flood of fork()ed
+ * processes that keep being killed early).
+ */
+ if (child_slot < 0 || !APR_PROC_CHECK_SIGNALED(exitwhy)) {
+ continue;
+ }
+ if (++successive_kills >= 3) {
+ if (successive_kills % 10 == 3) {
+ ap_log_error(APLOG_MARK, APLOG_WARNING, 0,
+ ap_server_conf, APLOGNO(10392)
+ "children are killed successively!");
+ }
+ continue;
+ }
+ ++remaining_children_to_start;
+ }
+ else {
+ successive_kills = 0;
+ }
+
+ 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;
+ }
+
+ max_daemon_used = 0;
+ for (i = 0; i < num_buckets; i++) {
+ perform_idle_server_maintenance(i, &max_daemon_used);
+ }
+ retained->max_daemon_used = max_daemon_used;
+ }
+}
+
+static int event_run(apr_pool_t * _pconf, apr_pool_t * plog, server_rec * s)
+{
+ int num_buckets = retained->mpm->num_buckets;
+ int remaining_children_to_start;
+ int i;
+
+ ap_log_pid(pconf, ap_pid_fname);
+
+ if (!retained->mpm->was_graceful) {
+ if (ap_run_pre_mpm(s->process->pool, SB_SHARED) != OK) {
+ retained->mpm->mpm_state = AP_MPMQ_STOPPING;
+ return !OK;
+ }
+ /* fix the generation number in the global score; we just got a new,
+ * cleared scoreboard
+ */
+ ap_scoreboard_image->global->running_generation = retained->mpm->my_generation;
+ }
+
+ ap_unixd_mpm_set_signals(pconf, one_process);
+
+ /* Don't thrash since num_buckets depends on the
+ * system and the number of online CPU cores...
+ */
+ if (active_daemons_limit < num_buckets)
+ active_daemons_limit = num_buckets;
+ if (ap_daemons_to_start < num_buckets)
+ ap_daemons_to_start = num_buckets;
+ /* We want to create as much children at a time as the number of buckets,
+ * so to optimally accept connections (evenly distributed across buckets).
+ * Thus min_spare_threads should at least maintain num_buckets children,
+ * and max_spare_threads allow num_buckets more children w/o triggering
+ * immediately (e.g. num_buckets idle threads margin, one per bucket).
+ */
+ if (min_spare_threads < threads_per_child * (num_buckets - 1) + num_buckets)
+ min_spare_threads = threads_per_child * (num_buckets - 1) + num_buckets;
+ if (max_spare_threads < min_spare_threads + (threads_per_child + 1) * num_buckets)
+ max_spare_threads = min_spare_threads + (threads_per_child + 1) * num_buckets;
+
+ /* 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 > active_daemons_limit) {
+ remaining_children_to_start = active_daemons_limit;
+ }
+ if (!retained->mpm->was_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);
+ ap_log_mpm_common(s);
+
+ retained->mpm->mpm_state = AP_MPMQ_RUNNING;
+
+ server_main_loop(remaining_children_to_start);
+ retained->mpm->mpm_state = AP_MPMQ_STOPPING;
+
+ if (retained->mpm->shutdown_pending && retained->mpm->is_ungraceful) {
+ /* Time to shut down:
+ * Kill child processes, tell them to call child_exit, etc...
+ */
+ for (i = 0; i < num_buckets; i++) {
+ ap_mpm_podx_killpg(all_buckets[i].pod, active_daemons_limit,
+ AP_MPM_PODX_RESTART);
+ }
+ ap_reclaim_child_processes(1, /* Start with SIGTERM */
+ event_note_child_stopped);
+
+ 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;
+ }
+
+ if (retained->mpm->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();
+ for (i = 0; i < num_buckets; i++) {
+ ap_mpm_podx_killpg(all_buckets[i].pod, active_daemons_limit,
+ AP_MPM_PODX_GRACEFUL);
+ }
+ ap_relieve_child_processes(event_note_child_stopped);
+
+ 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 */
+ retained->mpm->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_stopped);
+
+ active_children = 0;
+ for (index = 0; index < retained->max_daemon_used; ++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 (!retained->mpm->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.
+ */
+ for (i = 0; i < num_buckets; i++) {
+ ap_mpm_podx_killpg(all_buckets[i].pod, active_daemons_limit,
+ AP_MPM_PODX_RESTART);
+ }
+ ap_reclaim_child_processes(1, event_note_child_stopped);
+
+ return DONE;
+ }
+
+ /* we've been told to restart */
+ 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->mpm->my_generation;
+ ap_scoreboard_image->global->running_generation = retained->mpm->my_generation;
+
+ if (!retained->mpm->is_ungraceful) {
+ 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 */
+ for (i = 0; i < num_buckets; i++) {
+ ap_mpm_podx_killpg(all_buckets[i].pod, active_daemons_limit,
+ AP_MPM_PODX_GRACEFUL);
+ }
+
+ /* This is mostly for debugging... so that we know what is still
+ * gracefully dealing with existing request.
+ */
+
+ }
+ else {
+ ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf, APLOGNO(00494)
+ "SIGHUP received. Attempting to restart");
+ /* 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.
+ */
+ for (i = 0; i < num_buckets; i++) {
+ ap_mpm_podx_killpg(all_buckets[i].pod, active_daemons_limit,
+ AP_MPM_PODX_RESTART);
+ }
+
+ ap_reclaim_child_processes(1, /* Start with SIGTERM */
+ event_note_child_stopped);
+ }
+
+ return OK;
+}
+
+static void setup_slave_conn(conn_rec *c, void *csd)
+{
+ event_conn_state_t *mcs;
+ event_conn_state_t *cs;
+
+ mcs = ap_get_module_config(c->master->conn_config, &mpm_event_module);
+
+ cs = apr_pcalloc(c->pool, sizeof(*cs));
+ cs->c = c;
+ cs->r = NULL;
+ cs->sc = mcs->sc;
+ cs->suspended = 0;
+ cs->p = c->pool;
+ cs->bucket_alloc = c->bucket_alloc;
+ cs->pfd = mcs->pfd;
+ cs->pub = mcs->pub;
+ cs->pub.state = CONN_STATE_READ_REQUEST_LINE;
+ cs->pub.sense = CONN_SENSE_DEFAULT;
+
+ c->cs = &(cs->pub);
+ ap_set_module_config(c->conn_config, &mpm_event_module, cs);
+}
+
+static int event_pre_connection(conn_rec *c, void *csd)
+{
+ if (c->master && (!c->cs || c->cs == c->master->cs)) {
+ setup_slave_conn(c, csd);
+ }
+ return OK;
+}
+
+static int event_protocol_switch(conn_rec *c, request_rec *r, server_rec *s,
+ const char *protocol)
+{
+ if (!r && s) {
+ /* connection based switching of protocol, set the correct server
+ * configuration, so that timeouts, keepalives and such are used
+ * for the server that the connection was switched on.
+ * Normally, we set this on post_read_request, but on a protocol
+ * other than http/1.1, this might never happen.
+ */
+ event_conn_state_t *cs;
+
+ cs = ap_get_module_config(c->conn_config, &mpm_event_module);
+ cs->sc = ap_get_module_config(s->module_config, &mpm_event_module);
+ }
+ return DECLINED;
+}
+
+/* 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;
+ int num_buckets = 0;
+ ap_listen_rec **listen_buckets;
+ apr_status_t rv;
+ int i;
+
+ pconf = p;
+
+ /* the reverse of pre_config, we want this only the first time around */
+ if (retained->mpm->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 !OK;
+ }
+
+ if (one_process) {
+ num_buckets = 1;
+ }
+ else if (retained->mpm->was_graceful) {
+ /* Preserve the number of buckets on graceful restarts. */
+ num_buckets = retained->mpm->num_buckets;
+ }
+ if ((rv = ap_duplicate_listeners(pconf, ap_server_conf,
+ &listen_buckets, &num_buckets))) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT | level_flags, rv,
+ (startup ? NULL : s),
+ "could not duplicate listeners");
+ return !OK;
+ }
+
+ all_buckets = apr_pcalloc(pconf, num_buckets * sizeof(*all_buckets));
+ for (i = 0; i < num_buckets; i++) {
+ if (!one_process && /* no POD in one_process mode */
+ (rv = ap_mpm_podx_open(pconf, &all_buckets[i].pod))) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT | level_flags, rv,
+ (startup ? NULL : s),
+ "could not open pipe-of-death");
+ return !OK;
+ }
+ all_buckets[i].listeners = listen_buckets[i];
+ }
+
+ if (retained->mpm->max_buckets < num_buckets) {
+ int new_max, *new_ptr;
+ new_max = retained->mpm->max_buckets * 2;
+ if (new_max < num_buckets) {
+ new_max = num_buckets;
+ }
+ new_ptr = (int *)apr_palloc(ap_pglobal, new_max * sizeof(int));
+ if (retained->idle_spawn_rate) /* NULL at startup */
+ memcpy(new_ptr, retained->idle_spawn_rate,
+ retained->mpm->num_buckets * sizeof(int));
+ retained->idle_spawn_rate = new_ptr;
+ retained->mpm->max_buckets = new_max;
+ }
+ if (retained->mpm->num_buckets < num_buckets) {
+ int rate_max = 1;
+ /* If new buckets are added, set their idle spawn rate to
+ * the highest so far, so that they get filled as quickly
+ * as the existing ones.
+ */
+ for (i = 0; i < retained->mpm->num_buckets; i++) {
+ if (rate_max < retained->idle_spawn_rate[i]) {
+ rate_max = retained->idle_spawn_rate[i];
+ }
+ }
+ for (/* up to date i */; i < num_buckets; i++) {
+ retained->idle_spawn_rate[i] = rate_max;
+ }
+ }
+ retained->mpm->num_buckets = num_buckets;
+
+ /* for skiplist */
+ srand((unsigned int)apr_time_now());
+ 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_event_module";
+ int test_atomics = 0;
+
+ 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");
+ }
+
+ retained = ap_retained_data_get(userdata_key);
+ if (!retained) {
+ retained = ap_retained_data_create(userdata_key, sizeof(*retained));
+ retained->mpm = ap_unixd_mpm_get_retained_data();
+ if (retained->mpm->module_loads) {
+ test_atomics = 1;
+ }
+ }
+ retained->mpm->mpm_state = AP_MPMQ_STARTING;
+ if (retained->mpm->baton != retained) {
+ retained->mpm->was_graceful = 0;
+ retained->mpm->baton = retained;
+ }
+ ++retained->mpm->module_loads;
+
+ /* test once for correct operation of fdqueue */
+ if (test_atomics || retained->mpm->module_loads == 2) {
+ static apr_uint32_t foo1, foo2;
+
+ apr_atomic_set32(&foo1, 100);
+ foo2 = apr_atomic_add32(&foo1, -10);
+ if (foo2 != 100 || foo1 != 90) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, 0, NULL, APLOGNO(02405)
+ "atomics not working as expected - add32 of negative number");
+ return HTTP_INTERNAL_SERVER_ERROR;
+ }
+ }
+
+ /* sigh, want this only the second time around */
+ if (retained->mpm->module_loads == 2) {
+ rv = apr_pollset_create(&event_pollset, 1, plog,
+ APR_POLLSET_THREADSAFE | APR_POLLSET_NOCOPY);
+ if (rv != APR_SUCCESS) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, NULL, APLOGNO(00495)
+ "Couldn't create a Thread Safe Pollset. "
+ "Is it supported on your platform?"
+ "Also 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;
+ active_daemons_limit = server_limit;
+ threads_per_child = DEFAULT_THREADS_PER_CHILD;
+ max_workers = active_daemons_limit * threads_per_child;
+ defer_linger_chain = NULL;
+ had_healthy_child = 0;
+ ap_extended_status = 0;
+
+ event_pollset = NULL;
+ worker_queue_info = NULL;
+ listener_os_thread = NULL;
+ listensocks_disabled = 0;
+ listener_is_wakeable = 0;
+
+ return OK;
+}
+
+static int event_post_config(apr_pool_t *pconf, apr_pool_t *plog,
+ apr_pool_t *ptemp, server_rec *s)
+{
+ struct {
+ struct timeout_queue *tail, *q;
+ apr_hash_t *hash;
+ } wc, ka;
+
+ /* Not needed in pre_config stage */
+ if (ap_state_query(AP_SQ_MAIN_STATE) == AP_SQ_MS_CREATE_PRE_CONFIG) {
+ return OK;
+ }
+
+ wc.tail = ka.tail = NULL;
+ wc.hash = apr_hash_make(ptemp);
+ ka.hash = apr_hash_make(ptemp);
+
+ linger_q = TO_QUEUE_MAKE(pconf, apr_time_from_sec(MAX_SECS_TO_LINGER),
+ NULL);
+ short_linger_q = TO_QUEUE_MAKE(pconf, apr_time_from_sec(SECONDS_TO_LINGER),
+ NULL);
+
+ for (; s; s = s->next) {
+ event_srv_cfg *sc = apr_pcalloc(pconf, sizeof *sc);
+
+ ap_set_module_config(s->module_config, &mpm_event_module, sc);
+ if (!wc.tail) {
+ /* The main server uses the global queues */
+ wc.q = TO_QUEUE_MAKE(pconf, s->timeout, NULL);
+ apr_hash_set(wc.hash, &s->timeout, sizeof s->timeout, wc.q);
+ wc.tail = write_completion_q = wc.q;
+
+ ka.q = TO_QUEUE_MAKE(pconf, s->keep_alive_timeout, NULL);
+ apr_hash_set(ka.hash, &s->keep_alive_timeout,
+ sizeof s->keep_alive_timeout, ka.q);
+ ka.tail = keepalive_q = ka.q;
+ }
+ else {
+ /* The vhosts use any existing queue with the same timeout,
+ * or their own queue(s) if there isn't */
+ wc.q = apr_hash_get(wc.hash, &s->timeout, sizeof s->timeout);
+ if (!wc.q) {
+ wc.q = TO_QUEUE_MAKE(pconf, s->timeout, wc.tail);
+ apr_hash_set(wc.hash, &s->timeout, sizeof s->timeout, wc.q);
+ wc.tail = wc.tail->next = wc.q;
+ }
+
+ ka.q = apr_hash_get(ka.hash, &s->keep_alive_timeout,
+ sizeof s->keep_alive_timeout);
+ if (!ka.q) {
+ ka.q = TO_QUEUE_MAKE(pconf, s->keep_alive_timeout, ka.tail);
+ apr_hash_set(ka.hash, &s->keep_alive_timeout,
+ sizeof s->keep_alive_timeout, ka.q);
+ ka.tail = ka.tail->next = ka.q;
+ }
+ }
+ sc->wc_q = wc.q;
+ sc->ka_q = ka.q;
+ }
+
+ 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->mpm->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 %d servers, decreasing to %d.",
+ server_limit, 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 %d threads, decreasing to %d.",
+ thread_limit, 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 %d threads, decreasing to %d. "
+ "To increase, please see the ThreadLimit directive.",
+ threads_per_child, thread_limit, thread_limit);
+ } 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 %d, increasing to %d. "
+ "MaxRequestWorkers must be at least as large "
+ "as the number of threads in a single server.",
+ max_workers, threads_per_child, threads_per_child);
+ } 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;
+ }
+
+ active_daemons_limit = max_workers / threads_per_child;
+
+ if (max_workers % threads_per_child) {
+ int tmp_max_workers = active_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 ThreadsPerChild of %d, decreasing to nearest "
+ "multiple %d, for a maximum of %d servers.",
+ max_workers, threads_per_child, tmp_max_workers,
+ active_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 (active_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 would exceed ServerLimit of %d, decreasing to %d. "
+ "To increase, please see the ServerLimit directive.",
+ max_workers, active_daemons_limit, server_limit,
+ server_limit * threads_per_child);
+ } 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, active_daemons_limit, server_limit,
+ server_limit * threads_per_child);
+ }
+ active_daemons_limit = server_limit;
+ }
+
+ /* ap_daemons_to_start > active_daemons_limit checked in ap_mpm_run() */
+ if (ap_daemons_to_start < 1) {
+ 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 to avoid almost certain server "
+ "failure. Please read the documentation.",
+ min_spare_threads);
+ } 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;
+
+ 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_post_config(event_post_config, NULL, NULL, APR_HOOK_MIDDLE);
+ 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_pre_read_request(event_pre_read_request, NULL, NULL, APR_HOOK_MIDDLE);
+ ap_hook_post_read_request(event_post_read_request, NULL, NULL, APR_HOOK_MIDDLE);
+ ap_hook_mpm_get_name(event_get_name, NULL, NULL, APR_HOOK_MIDDLE);
+
+ ap_hook_pre_connection(event_pre_connection, NULL, NULL, APR_HOOK_REALLY_FIRST);
+ ap_hook_protocol_switch(event_protocol_switch, NULL, NULL, APR_HOOK_REALLY_FIRST);
+}
+
+static const char *set_daemons_to_start(cmd_parms *cmd, void *dummy,
+ const char *arg)
+{
+ const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
+ if (err != NULL) {
+ return err;
+ }
+
+ ap_daemons_to_start = atoi(arg);
+ return NULL;
+}
+
+static const char *set_min_spare_threads(cmd_parms * cmd, void *dummy,
+ const char *arg)
+{
+ const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
+ if (err != NULL) {
+ return err;
+ }
+
+ min_spare_threads = atoi(arg);
+ 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";
+
+ if (val <= 0)
+ return "AsyncRequestWorkerFactor argument must be a positive number";
+
+ worker_factor = val * WORKER_FACTOR_SCALE;
+ if (worker_factor < WORKER_FACTOR_SCALE) {
+ worker_factor = WORKER_FACTOR_SCALE;
+ }
+ 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_event) = {
+ 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 */
+};
diff --git a/server/mpm/event/mpm_default.h b/server/mpm/event/mpm_default.h
new file mode 100644
index 0000000..214caa0
--- /dev/null
+++ b/server/mpm/event/mpm_default.h
@@ -0,0 +1,56 @@
+/* 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.
+ */
+
+
+/**
+ * @file event/mpm_default.h
+ * @brief Event MPM defaults
+ *
+ * @defgroup APACHE_MPM_EVENT Event MPM
+ * @ingroup APACHE_INTERNAL
+ * @{
+ */
+
+#ifndef APACHE_MPM_DEFAULT_H
+#define APACHE_MPM_DEFAULT_H
+
+/* Number of servers to spawn off by default --- also, if fewer than
+ * this free when the caretaker checks, it will spawn more.
+ */
+#ifndef DEFAULT_START_DAEMON
+#define DEFAULT_START_DAEMON 3
+#endif
+
+/* Maximum number of *free* server processes --- more than this, and
+ * they will die off.
+ */
+
+#ifndef DEFAULT_MAX_FREE_DAEMON
+#define DEFAULT_MAX_FREE_DAEMON 10
+#endif
+
+/* Minimum --- fewer than this, and more will be created */
+
+#ifndef DEFAULT_MIN_FREE_DAEMON
+#define DEFAULT_MIN_FREE_DAEMON 3
+#endif
+
+#ifndef DEFAULT_THREADS_PER_CHILD
+#define DEFAULT_THREADS_PER_CHILD 25
+#endif
+
+#endif /* AP_MPM_DEFAULT_H */
+/** @} */