/*
- * $Id: sysdep.c 5882 2007-12-13 19:46:05Z davew $
+ * Thread handling stuff for Citadel server
*
- * Citadel "system dependent" stuff.
- * See copyright.txt for copyright information.
+ * Copyright (c) 1987-2021 by the citadel.org team
*
- * Here's where we have the Citadel thread implimentation
+ * This program is open source software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 3.
*
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
*/
#include <errno.h>
-
-#include "threads.h"
-#include "ctdl_module.h"
+#include <stdio.h>
+#include <syslog.h>
+#include <libcitadel.h>
#include "modules_init.h"
-#include "housekeeping.h"
+#include "serv_extensions.h"
+#include "ctdl_module.h"
#include "config.h"
+#include "context.h"
+#include "threads.h"
-/*
- * New thread interface.
- * To create a thread you must call one of the create thread functions.
- * You must pass it the address of (a pointer to a CtdlThreadNode initialised to NULL) like this
- * struct CtdlThreadNode *node = NULL;
- * pass in &node
- * If the thread is created *node will point to the thread control structure for the created thread.
- * If the thread creation fails *node remains NULL
- * Do not free the memory pointed to by *node, it doesn't belong to you.
- * This new interface duplicates much of the eCrash stuff. We should go for closer integration since that would
- * remove the need for the calls to eCrashRegisterThread and friends
- */
-
-static int num_threads = 0; /* Current number of threads */
-static int num_workers = 0; /* Current number of worker threads */
-
-struct CtdlThreadNode *CtdlThreadList = NULL;
-struct CtdlThreadNode *CtdlThreadSchedList = NULL;
-
-/*
- * Condition variable and Mutex for thread garbage collection
- */
-/*static pthread_mutex_t thread_gc_mutex = PTHREAD_MUTEX_INITIALIZER;
-static pthread_cond_t thread_gc_cond = PTHREAD_COND_INITIALIZER;
-*/
-static pthread_t GC_thread;
-static char *CtdlThreadStates[CTDL_THREAD_LAST_STATE];
-double CtdlThreadLoadAvg = 0;
-double CtdlThreadWorkerAvg = 0;
+int num_workers = 0; /* Current number of worker threads */
+int active_workers = 0; /* Number of ACTIVE worker threads */
pthread_key_t ThreadKey;
-
pthread_mutex_t Critters[MAX_SEMAPHORES]; /* Things needing locking */
+struct thread_tsd masterTSD;
+int server_shutting_down = 0; /* set to nonzero during shutdown */
+pthread_mutex_t ThreadCountMutex;
-
-
-void InitialiseSemaphores(void)
+void InitializeSemaphores(void)
{
int i;
}
-
-
/*
* Obtain a semaphore lock to begin a critical section.
* but only if no one else has one
* transaction; this could lead to deadlock.
*/
if ( (which_one != S_FLOORCACHE)
-#ifdef DEBUG_MEMORY_LEAKS
- && (which_one != S_DEBUGMEMLEAKS)
-#endif
- && (which_one != S_RPLIST)
+ && (which_one != S_NETCONFIGS)
) {
cdb_check_handles();
}
*/
void begin_critical_section(int which_one)
{
- /* CtdlLogPrintf(CTDL_DEBUG, "begin_critical_section(%d)\n", which_one); */
-
/* For all types of critical sections except those listed here,
* ensure nobody ever tries to do a critical section within a
* transaction; this could lead to deadlock.
*/
if ( (which_one != S_FLOORCACHE)
-#ifdef DEBUG_MEMORY_LEAKS
- && (which_one != S_DEBUGMEMLEAKS)
-#endif
- && (which_one != S_RPLIST)
+ && (which_one != S_NETCONFIGS)
) {
cdb_check_handles();
}
pthread_mutex_lock(&Critters[which_one]);
}
+
/*
* Release a semaphore lock to end a critical section.
*/
/*
- * A function to destroy the TSD
- */
-static void ctdl_thread_internal_dest_tsd(void *arg)
-{
- if (arg != NULL) {
- check_handles(arg);
- free(arg);
- }
-}
-
-
-/*
- * A function to initialise the thread TSD
- */
-void ctdl_thread_internal_init_tsd(void)
-{
- int ret;
-
- if ((ret = pthread_key_create(&ThreadKey, ctdl_thread_internal_dest_tsd))) {
- lprintf(CTDL_EMERG, "pthread_key_create: %s\n",
- strerror(ret));
- exit(CTDLEXIT_DB);
- }
-}
-
-/*
- * Ensure that we have a key for thread-specific data.
- *
- * This should be called immediately after startup by any thread
- *
- */
-void CtdlThreadAllocTSD(void)
-{
- ThreadTSD *tsd;
-
- if (pthread_getspecific(ThreadKey) != NULL)
- return;
-
- tsd = malloc(sizeof(ThreadTSD));
-
- tsd->tid = NULL;
-
- memset(tsd->cursors, 0, sizeof tsd->cursors);
- tsd->self = NULL;
-
- pthread_setspecific(ThreadKey, tsd);
-}
-
-
-void ctdl_thread_internal_free_tsd(void)
-{
- ctdl_thread_internal_dest_tsd(pthread_getspecific(ThreadKey));
- pthread_setspecific(ThreadKey, NULL);
-}
-
-
-void ctdl_thread_internal_cleanup(void)
-{
- int i;
- struct CtdlThreadNode *this_thread, *that_thread;
-
- for (i=0; i<CTDL_THREAD_LAST_STATE; i++)
- {
- free (CtdlThreadStates[i]);
- }
-
- /* Clean up the scheduled thread list */
- this_thread = CtdlThreadSchedList;
- while (this_thread)
- {
- that_thread = this_thread;
- this_thread = this_thread->next;
- pthread_mutex_destroy(&that_thread->ThreadMutex);
- pthread_cond_destroy(&that_thread->ThreadCond);
- pthread_mutex_destroy(&that_thread->SleepMutex);
- pthread_cond_destroy(&that_thread->SleepCond);
- pthread_attr_destroy(&that_thread->attr);
- free(that_thread);
- }
- ctdl_thread_internal_free_tsd();
-}
-
-void ctdl_thread_internal_init(void)
-{
- struct CtdlThreadNode *this_thread;
- int ret = 0;
-
- GC_thread = pthread_self();
- CtdlThreadStates[CTDL_THREAD_INVALID] = strdup ("Invalid Thread");
- CtdlThreadStates[CTDL_THREAD_VALID] = strdup("Valid Thread");
- CtdlThreadStates[CTDL_THREAD_CREATE] = strdup("Thread being Created");
- CtdlThreadStates[CTDL_THREAD_CANCELLED] = strdup("Thread Cancelled");
- CtdlThreadStates[CTDL_THREAD_EXITED] = strdup("Thread Exited");
- CtdlThreadStates[CTDL_THREAD_STOPPING] = strdup("Thread Stopping");
- CtdlThreadStates[CTDL_THREAD_STOP_REQ] = strdup("Thread Stop Requested");
- CtdlThreadStates[CTDL_THREAD_SLEEPING] = strdup("Thread Sleeping");
- CtdlThreadStates[CTDL_THREAD_RUNNING] = strdup("Thread Running");
- CtdlThreadStates[CTDL_THREAD_BLOCKED] = strdup("Thread Blocked");
-
- /* Get ourself a thread entry */
- this_thread = malloc(sizeof(struct CtdlThreadNode));
- if (this_thread == NULL) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system, can't allocate CtdlThreadNode, exiting\n");
- return;
- }
- // Ensuring this is zero'd means we make sure the thread doesn't start doing its thing until we are ready.
- memset (this_thread, 0, sizeof(struct CtdlThreadNode));
-
- pthread_mutex_init (&(this_thread->ThreadMutex), NULL);
- pthread_cond_init (&(this_thread->ThreadCond), NULL);
- pthread_mutex_init (&(this_thread->SleepMutex), NULL);
- pthread_cond_init (&(this_thread->SleepCond), NULL);
-
- /* We are garbage collector so create us as running */
- this_thread->state = CTDL_THREAD_RUNNING;
-
- if ((ret = pthread_attr_init(&this_thread->attr))) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system, pthread_attr_init: %s\n", strerror(ret));
- free(this_thread);
- return;
- }
-
- this_thread->name = "Garbage Collection Thread";
-
- this_thread->tid = GC_thread;
- CT = this_thread;
-
- num_threads++; // Increase the count of threads in the system.
-
- this_thread->next = CtdlThreadList;
- CtdlThreadList = this_thread;
- if (this_thread->next)
- this_thread->next->prev = this_thread;
- /* Set up start times */
- gettimeofday(&this_thread->start_time, NULL); /* Time this thread started */
- memcpy(&this_thread->last_state_change, &this_thread->start_time, sizeof (struct timeval)); /* Changed state so mark it. */
-}
-
-
-/*
- * A function to update a threads load averages
- */
- void ctdl_thread_internal_update_avgs(struct CtdlThreadNode *this_thread)
- {
- struct timeval now, result;
- double last_duration;
-
- gettimeofday(&now, NULL);
- timersub(&now, &(this_thread->last_state_change), &result);
- pthread_mutex_lock(&this_thread->ThreadMutex);
- // result now has a timeval for the time we spent in the last state since we last updated
- last_duration = (double)result.tv_sec + ((double)result.tv_usec / (double) 1000000);
- if (this_thread->state == CTDL_THREAD_SLEEPING)
- this_thread->avg_sleeping += last_duration;
- if (this_thread->state == CTDL_THREAD_RUNNING)
- this_thread->avg_running += last_duration;
- if (this_thread->state == CTDL_THREAD_BLOCKED)
- this_thread->avg_blocked += last_duration;
- memcpy (&this_thread->last_state_change, &now, sizeof (struct timeval));
- pthread_mutex_unlock(&this_thread->ThreadMutex);
-}
-
-/*
- * A function to chenge the state of a thread
- */
-void ctdl_thread_internal_change_state (struct CtdlThreadNode *this_thread, enum CtdlThreadState new_state)
-{
- /*
- * Wether we change state or not we need update the load values
- */
- ctdl_thread_internal_update_avgs(this_thread);
- pthread_mutex_lock(&this_thread->ThreadMutex); /* To prevent race condition of a sleeping thread */
- if ((new_state == CTDL_THREAD_STOP_REQ) && (this_thread->state > CTDL_THREAD_STOP_REQ))
- this_thread->state = new_state;
- if (((new_state == CTDL_THREAD_SLEEPING) || (new_state == CTDL_THREAD_BLOCKED)) && (this_thread->state == CTDL_THREAD_RUNNING))
- this_thread->state = new_state;
- if ((new_state == CTDL_THREAD_RUNNING) && ((this_thread->state == CTDL_THREAD_SLEEPING) || (this_thread->state == CTDL_THREAD_BLOCKED)))
- this_thread->state = new_state;
- pthread_mutex_unlock(&this_thread->ThreadMutex);
-}
-
-
-/*
- * A function to tell all threads to exit
- */
-void CtdlThreadStopAll(void)
-{
- //FIXME: The signalling of the condition should not be in the critical_section
- // We need to build a list of threads we are going to signal and then signal them afterwards
-
- struct CtdlThreadNode *this_thread;
-
- begin_critical_section(S_THREAD_LIST);
- this_thread = CtdlThreadList;
- while(this_thread)
- {
-#ifdef THREADS_USESIGNALS
- pthread_kill(this_thread->tid, SIGHUP);
-#endif
- ctdl_thread_internal_change_state (this_thread, CTDL_THREAD_STOP_REQ);
- pthread_cond_signal(&this_thread->ThreadCond);
- pthread_cond_signal(&this_thread->SleepCond);
- CtdlLogPrintf(CTDL_DEBUG, "Thread system stopping thread \"%s\" (%ld).\n", this_thread->name, this_thread->tid);
- this_thread = this_thread->next;
- }
- end_critical_section(S_THREAD_LIST);
-}
-
-
-/*
- * A function to wake up all sleeping threads
- */
-void CtdlThreadWakeAll(void)
-{
- struct CtdlThreadNode *this_thread;
-
- CtdlLogPrintf(CTDL_DEBUG, "Thread system waking all threads.\n");
-
- begin_critical_section(S_THREAD_LIST);
- this_thread = CtdlThreadList;
- while(this_thread)
- {
- if (!this_thread->thread_func)
- {
- pthread_cond_signal(&this_thread->ThreadCond);
- pthread_cond_signal(&this_thread->SleepCond);
- }
- this_thread = this_thread->next;
- }
- end_critical_section(S_THREAD_LIST);
-}
-
-
-/*
- * A function to return the number of threads running in the system
- */
-int CtdlThreadGetCount(void)
-{
- return num_threads;
-}
-
-int CtdlThreadGetWorkers(void)
-{
- return num_workers;
-}
-
-double CtdlThreadGetWorkerAvg(void)
-{
- double ret;
-
- begin_critical_section(S_THREAD_LIST);
- ret = CtdlThreadWorkerAvg;
- end_critical_section(S_THREAD_LIST);
- return ret;
-}
-
-double CtdlThreadGetLoadAvg(void)
-{
- double ret;
-
- begin_critical_section(S_THREAD_LIST);
- ret = CtdlThreadLoadAvg;
- end_critical_section(S_THREAD_LIST);
- return ret;
-}
-
-
-
-
-/*
- * A function to rename a thread
- * Returns a const char *
- */
-const char *CtdlThreadName(const char *name)
-{
- const char *old_name;
-
- if (!CT)
- {
- CtdlLogPrintf(CTDL_WARNING, "Thread system WARNING. Attempt to CtdlThreadRename() a non thread. %s\n", name);
- return NULL;
- }
-// FIXME: do we need this lock? I think not since the pointer asignmaent should be atomic
- pthread_mutex_lock(&CT->ThreadMutex);
- old_name = CT->name;
- if (name)
- CT->name = name;
- pthread_mutex_unlock(&CT->ThreadMutex);
- return (old_name);
-}
-
-
-/*
- * A function to force a thread to exit
- */
-void CtdlThreadCancel(struct CtdlThreadNode *thread)
-{
- struct CtdlThreadNode *this_thread;
-
- if (!thread)
- this_thread = CT;
- else
- this_thread = thread;
- if (!this_thread)
- {
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC. Attempt to CtdlThreadCancel() a non thread.\n");
- CtdlThreadStopAll();
- return;
- }
-
- if (!this_thread->thread_func)
- {
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC. Attempt to CtdlThreadCancel() the garbage collector.\n");
- CtdlThreadStopAll();
- return;
- }
-
- ctdl_thread_internal_change_state (this_thread, CTDL_THREAD_CANCELLED);
- pthread_cancel(this_thread->tid);
-}
-
-
-
-/*
- * A function for a thread to check if it has been asked to stop
- */
-int CtdlThreadCheckStop(void)
-{
- int state;
-
- if (!CT)
- {
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC, CtdlThreadCheckStop() called by a non thread.\n");
- CtdlThreadStopAll();
- return -1;
- }
-
- state = CT->state;
-
-#ifdef THREADS_USERSIGNALS
- if (CT->signal)
- CtdlLogPrintf(CTDL_DEBUG, "Thread \"%s\" caught signal %d.\n", CT->name, CT->signal);
-#endif
- pthread_mutex_lock(&CT->ThreadMutex);
- if(state == CTDL_THREAD_STOP_REQ)
- {
- CT->state = CTDL_THREAD_STOPPING;
- pthread_mutex_unlock(&CT->ThreadMutex);
- return -1;
- }
- else if((state < CTDL_THREAD_STOP_REQ) && (state > CTDL_THREAD_CREATE))
- {
- pthread_mutex_unlock(&CT->ThreadMutex);
- return -1;
- }
- pthread_mutex_unlock(&CT->ThreadMutex);
- return 0;
-}
-
-
-/*
- * A function to ask a thread to exit
- * The thread must call CtdlThreadCheckStop() periodically to determine if it should exit
- */
-void CtdlThreadStop(struct CtdlThreadNode *thread)
-{
- struct CtdlThreadNode *this_thread;
-
- if (!thread)
- this_thread = CT;
- else
- this_thread = thread;
- if (!this_thread)
- return;
- if (!(this_thread->thread_func))
- return; // Don't stop garbage collector
-#ifdef THREADS_USESIGNALS
- pthread_kill(this_thread->tid, SIGHUP);
-#endif
- ctdl_thread_internal_change_state (this_thread, CTDL_THREAD_STOP_REQ);
- pthread_cond_signal(&this_thread->ThreadCond);
- pthread_cond_signal(&this_thread->SleepCond);
-}
-
-/*
- * So we now have a sleep command that works with threads but it is in seconds
- */
-void CtdlThreadSleep(int secs)
-{
- struct timespec wake_time;
- struct timeval time_now;
-
-
- if (!CT)
- {
- CtdlLogPrintf(CTDL_WARNING, "CtdlThreadSleep() called by something that is not a thread. Should we die?\n");
- return;
- }
-
- memset (&wake_time, 0, sizeof(struct timespec));
- gettimeofday(&time_now, NULL);
- wake_time.tv_sec = time_now.tv_sec + secs;
- wake_time.tv_nsec = time_now.tv_usec * 10;
-
- ctdl_thread_internal_change_state (CT, CTDL_THREAD_SLEEPING);
-
- pthread_mutex_lock(&CT->ThreadMutex); /* Prevent something asking us to awaken before we've gone to sleep */
- pthread_cond_timedwait(&CT->SleepCond, &CT->ThreadMutex, &wake_time);
- pthread_mutex_unlock(&CT->ThreadMutex);
-
- ctdl_thread_internal_change_state (CT, CTDL_THREAD_RUNNING);
-}
-
-
-/*
- * Routine to clean up our thread function on exit
- */
-static void ctdl_internal_thread_cleanup(void *arg)
-{
- /*
- * In here we were called by the current thread because it is exiting
- * NB. WE ARE THE CURRENT THREAD
- */
- CtdlLogPrintf(CTDL_NOTICE, "Thread \"%s\" (%ld) exited.\n", CT->name, CT->tid);
-
- #ifdef HAVE_BACKTRACE
- eCrash_UnregisterThread();
- #endif
-
- pthread_mutex_lock(&CT->ThreadMutex);
- CT->state = CTDL_THREAD_EXITED; // needs to be last thing else house keeping will unlink us too early
- pthread_mutex_unlock(&CT->ThreadMutex);
-}
-
-/*
- * A quick function to show the load averages
- */
-void ctdl_thread_internal_calc_loadavg(void)
-{
- struct CtdlThreadNode *that_thread;
- double load_avg, worker_avg;
- int workers = 0;
-
- that_thread = CtdlThreadList;
- load_avg = 0;
- worker_avg = 0;
- while(that_thread)
- {
- /* Update load averages */
- ctdl_thread_internal_update_avgs(that_thread);
- pthread_mutex_lock(&that_thread->ThreadMutex);
- that_thread->load_avg = that_thread->avg_sleeping + that_thread->avg_running + that_thread->avg_blocked;
- that_thread->load_avg = that_thread->avg_running / that_thread->load_avg * 100;
- that_thread->avg_sleeping /= 2;
- that_thread->avg_running /= 2;
- that_thread->avg_blocked /= 2;
- load_avg += that_thread->load_avg;
- if (that_thread->flags & CTDLTHREAD_WORKER)
- {
- worker_avg += that_thread->load_avg;
- workers++;
- }
-#ifdef WITH_THREADLOG
- CtdlLogPrintf(CTDL_DEBUG, "CtdlThread, \"%s\" (%ld) \"%s\" %f %f %f %f.\n",
- that_thread->name,
- that_thread->tid,
- CtdlThreadStates[that_thread->state],
- that_thread->avg_sleeping,
- that_thread->avg_running,
- that_thread->avg_blocked,
- that_thread->load_avg);
-#endif
- pthread_mutex_unlock(&that_thread->ThreadMutex);
- that_thread = that_thread->next;
+ * Return a pointer to our thread-specific (not session-specific) data.
+ */
+struct thread_tsd *MyThread(void) {
+ struct thread_tsd *c = (struct thread_tsd *) pthread_getspecific(ThreadKey) ;
+ if (!c) {
+ return &masterTSD;
}
- CtdlThreadLoadAvg = load_avg/num_threads;
- CtdlThreadWorkerAvg = worker_avg/workers;
-#ifdef WITH_THREADLOG
- CtdlLogPrintf(CTDL_INFO, "System load average %f, workers averag %f, threads %d, workers %d, sessions %d\n", CtdlThreadLoadAvg, CtdlThreadWorkerAvg, num_threads, num_workers, num_sessions);
-#endif
+ return c;
}
-/*
- * Garbage collection routine.
- * Gets called by main() in a loop to clean up the thread list periodically.
+/*
+ * Called by CtdlThreadCreate()
+ * We have to pass through here before starting our thread in order to create a set of data
+ * that is thread-specific rather than session-specific.
*/
-void CtdlThreadGC (void)
-{
- struct CtdlThreadNode *this_thread, *that_thread;
- int workers = 0;
- int ret=0;
-
- begin_critical_section(S_THREAD_LIST);
-
- /* Handle exiting of garbage collector thread */
- if(num_threads == 1)
- CtdlThreadList->state = CTDL_THREAD_EXITED;
-
-#ifdef WITH_THREADLOG
- CtdlLogPrintf(CTDL_DEBUG, "Thread system running garbage collection.\n");
-#endif
- /*
- * Woke up to do garbage collection
- */
- this_thread = CtdlThreadList;
- while(this_thread)
- {
- that_thread = this_thread;
- this_thread = this_thread->next;
-
- /* Do we need to clean up this thread? */
- pthread_mutex_lock(&that_thread->ThreadMutex);
- if (that_thread->state != CTDL_THREAD_EXITED)
- {
- if(that_thread->flags & CTDLTHREAD_WORKER)
- workers++; /* Sanity check on number of worker threads */
- pthread_mutex_unlock(&that_thread->ThreadMutex);
- continue;
- }
-
- if (pthread_equal(that_thread->tid, pthread_self()) && that_thread->thread_func)
- { /* Sanity check */
- pthread_mutex_unlock(&that_thread->ThreadMutex);
- end_critical_section(S_THREAD_LIST);
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC, a thread is trying to clean up after itself.\n");
- abort();
- return;
- }
-
- if (num_threads <= 0)
- { /* Sanity check */
- pthread_mutex_unlock(&that_thread->ThreadMutex);
- end_critical_section(S_THREAD_LIST);
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC, num_threads <= 0 and trying to do Garbage Collection.\n");
- abort();
- return;
- }
-
- if(that_thread->flags & CTDLTHREAD_WORKER)
- num_workers--; /* This is a wroker thread so reduce the count. */
- num_threads--;
- /* If we are unlinking the list head then the next becomes the list head */
- if(that_thread->prev)
- that_thread->prev->next = that_thread->next;
- else
- CtdlThreadList = that_thread->next;
- if(that_thread->next)
- that_thread->next->prev = that_thread->prev;
-
- pthread_mutex_unlock(&that_thread->ThreadMutex);
- pthread_cond_signal(&that_thread->ThreadCond);
- pthread_cond_signal(&that_thread->SleepCond); // Make sure this thread is awake
- pthread_mutex_lock(&that_thread->ThreadMutex); // Make sure it has done what its doing
- pthread_mutex_unlock(&that_thread->ThreadMutex);
- /*
- * Join on the thread to do clean up and prevent memory leaks
- * Also makes sure the thread has cleaned up after itself before we remove it from the list
- * We can join on the garbage collector thread the join should just return EDEADLCK
- */
- ret = pthread_join (that_thread->tid, NULL);
- if (ret == EDEADLK)
- CtdlLogPrintf(CTDL_DEBUG, "Garbage collection on own thread.\n");
- else if (ret == EINVAL)
- CtdlLogPrintf(CTDL_DEBUG, "Garbage collection, that thread already joined on.\n");
- else if (ret == ESRCH)
- CtdlLogPrintf(CTDL_DEBUG, "Garbage collection, no thread to join on.\n");
- else if (ret != 0)
- CtdlLogPrintf(CTDL_DEBUG, "Garbage collection, pthread_join returned an unknown error.\n");
- /*
- * Now we own that thread entry
- */
- CtdlLogPrintf(CTDL_INFO, "Garbage Collection for thread \"%s\" (%ld).\n", that_thread->name, that_thread->tid);
- pthread_mutex_destroy(&that_thread->ThreadMutex);
- pthread_cond_destroy(&that_thread->ThreadCond);
- pthread_mutex_destroy(&that_thread->SleepMutex);
- pthread_cond_destroy(&that_thread->SleepCond);
- pthread_attr_destroy(&that_thread->attr);
- free(that_thread);
- }
-
- /* Sanity check number of worker threads */
- if (workers != num_workers)
- {
- end_critical_section(S_THREAD_LIST);
- CtdlLogPrintf(CTDL_EMERG,
- "Thread system PANIC, discrepancy in number of worker threads. Counted %d, should be %d.\n",
- workers, num_workers
- );
- abort();
- }
- end_critical_section(S_THREAD_LIST);
-}
-
-
-
-
-/*
- * Runtime function for a Citadel Thread.
- * This initialises the threads environment and then calls the user supplied thread function
- * Note that this is the REAL thread function and wraps the users thread function.
- */
-static void *ctdl_internal_thread_func (void *arg)
+void *CTC_backend(void *supplied_start_routine)
{
- struct CtdlThreadNode *this_thread;
- void *ret = NULL;
+ struct thread_tsd *mytsd;
+ void *(*start_routine)(void*) = supplied_start_routine;
- /* lock and unlock the thread list.
- * This causes this thread to wait until all its creation stuff has finished before it
- * can continue its execution.
- */
- begin_critical_section(S_THREAD_LIST);
- this_thread = (struct CtdlThreadNode *) arg;
- gettimeofday(&this_thread->start_time, NULL); /* Time this thread started */
- pthread_mutex_lock(&this_thread->ThreadMutex);
-
- // Register the cleanup function to take care of when we exit.
- pthread_cleanup_push(ctdl_internal_thread_cleanup, NULL);
- // Get our thread data structure
- CtdlThreadAllocTSD();
- CT = this_thread;
- this_thread->pid = getpid();
- memcpy(&this_thread->last_state_change, &this_thread->start_time, sizeof (struct timeval)); /* Changed state so mark it. */
- /* Only change to running state if we weren't asked to stop during the create cycle
- * Other wise there is a window to allow this threads creation to continue to full grown and
- * therby prevent a shutdown of the server.
- */
- pthread_mutex_unlock(&this_thread->ThreadMutex);
-
- if (!CtdlThreadCheckStop())
- {
- pthread_mutex_lock(&this_thread->ThreadMutex);
- this_thread->state = CTDL_THREAD_RUNNING;
- pthread_mutex_unlock(&this_thread->ThreadMutex);
- }
- end_critical_section(S_THREAD_LIST);
-
- // Register for tracing
- #ifdef HAVE_BACKTRACE
- eCrash_RegisterThread(this_thread->name, 0);
- #endif
-
- // Tell the world we are here
- CtdlLogPrintf(CTDL_NOTICE, "Created a new thread \"%s\" (%ld). \n", this_thread->name, this_thread->tid);
+ mytsd = (struct thread_tsd *) malloc(sizeof(struct thread_tsd));
+ memset(mytsd, 0, sizeof(struct thread_tsd));
+ pthread_setspecific(ThreadKey, (const void *) mytsd);
-
-
- /*
- * run the thread to do the work but only if we haven't been asked to stop
- */
- if (!CtdlThreadCheckStop())
- ret = (this_thread->thread_func)(this_thread->user_args);
-
- /*
- * Our thread is exiting either because it wanted to end or because the server is stopping
- * We need to clean up
- */
- pthread_cleanup_pop(1); // Execute our cleanup routine and remove it
-
- return(ret);
+ start_routine(NULL);
+ // free(mytsd);
+ return(NULL);
}
-
/*
- * Internal function to create a thread.
- * Must be called from within a S_THREAD_LIST critical section
+ * Function to create a thread.
*/
-struct CtdlThreadNode *ctdl_internal_create_thread(char *name, long flags, void *(*thread_func) (void *arg), void *args)
+void CtdlThreadCreate(void *(*start_routine)(void*))
{
+ pthread_t thread;
+ pthread_attr_t attr;
int ret = 0;
- struct CtdlThreadNode *this_thread;
-
- if (num_threads >= 32767)
- {
- CtdlLogPrintf(CTDL_EMERG, "Thread system. Thread list full.\n");
- return NULL;
- }
-
- this_thread = malloc(sizeof(struct CtdlThreadNode));
- if (this_thread == NULL) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system, can't allocate CtdlThreadNode, exiting\n");
- return NULL;
- }
- // Ensuring this is zero'd means we make sure the thread doesn't start doing its thing until we are ready.
- memset (this_thread, 0, sizeof(struct CtdlThreadNode));
-
- /* Create the mutex's early so we can use them */
- pthread_mutex_init (&(this_thread->ThreadMutex), NULL);
- pthread_cond_init (&(this_thread->ThreadCond), NULL);
- pthread_mutex_init (&(this_thread->SleepMutex), NULL);
- pthread_cond_init (&(this_thread->SleepCond), NULL);
-
- pthread_mutex_lock(&this_thread->ThreadMutex);
-
- this_thread->state = CTDL_THREAD_CREATE;
-
- if ((ret = pthread_attr_init(&this_thread->attr))) {
- pthread_mutex_unlock(&this_thread->ThreadMutex);
- pthread_mutex_destroy(&(this_thread->ThreadMutex));
- pthread_cond_destroy(&(this_thread->ThreadCond));
- pthread_mutex_destroy(&(this_thread->SleepMutex));
- pthread_cond_destroy(&(this_thread->SleepCond));
- CtdlLogPrintf(CTDL_EMERG, "Thread system, pthread_attr_init: %s\n", strerror(ret));
- free(this_thread);
- return NULL;
- }
- /* Our per-thread stacks need to be bigger than the default size,
- * otherwise the MIME parser crashes on FreeBSD, and the IMAP service
- * crashes on 64-bit Linux.
- */
- if (flags & CTDLTHREAD_BIGSTACK)
- {
-#ifdef WITH_THREADLOG
- CtdlLogPrintf(CTDL_INFO, "Thread system. Creating BIG STACK thread.\n");
-#endif
- if ((ret = pthread_attr_setstacksize(&this_thread->attr, THREADSTACKSIZE))) {
- pthread_mutex_unlock(&this_thread->ThreadMutex);
- pthread_mutex_destroy(&(this_thread->ThreadMutex));
- pthread_cond_destroy(&(this_thread->ThreadCond));
- pthread_mutex_destroy(&(this_thread->SleepMutex));
- pthread_cond_destroy(&(this_thread->SleepCond));
- pthread_attr_destroy(&this_thread->attr);
- CtdlLogPrintf(CTDL_EMERG, "Thread system, pthread_attr_setstacksize: %s\n",
- strerror(ret));
- free(this_thread);
- return NULL;
- }
- }
-
- /*
- * If we got here we are going to create the thread so we must initilise the structure
- * first because most implimentations of threading can't create it in a stopped state
- * and it might want to do things with its structure that aren't initialised otherwise.
- */
- if(name)
- {
- this_thread->name = name;
- }
- else
- {
- this_thread->name = "Un-named Thread";
- }
-
- this_thread->flags = flags;
- this_thread->thread_func = thread_func;
- this_thread->user_args = args;
- /* Set this new thread with an avg_blocked of 2. We do this so that its creation affects the
- * load average for the system. If we don't do this then we create a mass of threads at the same time
- * because the creation didn't affect the load average.
- */
- this_thread->avg_blocked = 2;
-
- /*
- * We pass this_thread into the thread as its args so that it can find out information
- * about itself and it has a bit of storage space for itself, not to mention that the REAL
- * thread function needs to finish off the setup of the structure
- */
- if ((ret = pthread_create(&this_thread->tid, &this_thread->attr, ctdl_internal_thread_func, this_thread) != 0))
- {
-
- CtdlLogPrintf(CTDL_ALERT, "Thread system, Can't create thread: %s\n",
- strerror(ret));
- pthread_mutex_unlock(&this_thread->ThreadMutex);
- pthread_mutex_destroy(&(this_thread->ThreadMutex));
- pthread_cond_destroy(&(this_thread->ThreadCond));
- pthread_mutex_destroy(&(this_thread->SleepMutex));
- pthread_cond_destroy(&(this_thread->SleepCond));
- pthread_attr_destroy(&this_thread->attr);
- free(this_thread);
- return NULL;
- }
-
- num_threads++; // Increase the count of threads in the system.
- if(this_thread->flags & CTDLTHREAD_WORKER)
- num_workers++;
-
- this_thread->next = CtdlThreadList;
- CtdlThreadList = this_thread;
- if (this_thread->next)
- this_thread->next->prev = this_thread;
-
- pthread_mutex_unlock(&this_thread->ThreadMutex);
-
- ctdl_thread_internal_calc_loadavg();
- return this_thread;
+ ret = pthread_attr_init(&attr);
+ ret = pthread_attr_setstacksize(&attr, THREADSTACKSIZE);
+ ret = pthread_create(&thread, &attr, CTC_backend, (void *)start_routine);
+ if (ret != 0) syslog(LOG_ERR, "pthread_create() : %m");
}
-/*
- * Wrapper function to create a thread
- * ensures the critical section and other protections are in place.
- * char *name = name to give to thread, if NULL, use generic name
- * int flags = flags to determine type of thread and standard facilities
- */
-struct CtdlThreadNode *CtdlThreadCreate(char *name, long flags, void *(*thread_func) (void *arg), void *args)
-{
- struct CtdlThreadNode *ret = NULL;
-
- begin_critical_section(S_THREAD_LIST);
- ret = ctdl_internal_create_thread(name, flags, thread_func, args);
- end_critical_section(S_THREAD_LIST);
- return ret;
-}
-
-
-
-/*
- * Internal function to schedule a thread.
- * Must be called from within a S_THREAD_LIST critical section
- */
-struct CtdlThreadNode *CtdlThreadSchedule(char *name, long flags, void *(*thread_func) (void *arg), void *args, time_t when)
-{
- int ret = 0;
- struct CtdlThreadNode *this_thread;
-
- if (num_threads >= 32767)
- {
- CtdlLogPrintf(CTDL_EMERG, "Thread system. Thread list full.\n");
- return NULL;
- }
-
- this_thread = malloc(sizeof(struct CtdlThreadNode));
- if (this_thread == NULL) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system, can't allocate CtdlThreadNode, exiting\n");
- return NULL;
- }
- // Ensuring this is zero'd means we make sure the thread doesn't start doing its thing until we are ready.
- memset (this_thread, 0, sizeof(struct CtdlThreadNode));
-
- /* Create the mutex's early so we can use them */
- pthread_mutex_init (&(this_thread->ThreadMutex), NULL);
- pthread_cond_init (&(this_thread->ThreadCond), NULL);
- pthread_mutex_init (&(this_thread->SleepMutex), NULL);
- pthread_cond_init (&(this_thread->SleepCond), NULL);
-
- this_thread->state = CTDL_THREAD_CREATE;
-
- if ((ret = pthread_attr_init(&this_thread->attr))) {
- pthread_mutex_destroy(&(this_thread->ThreadMutex));
- pthread_cond_destroy(&(this_thread->ThreadCond));
- pthread_mutex_destroy(&(this_thread->SleepMutex));
- pthread_cond_destroy(&(this_thread->SleepCond));
- CtdlLogPrintf(CTDL_EMERG, "Thread system, pthread_attr_init: %s\n", strerror(ret));
- free(this_thread);
- return NULL;
- }
-
- /* Our per-thread stacks need to be bigger than the default size,
- * otherwise the MIME parser crashes on FreeBSD, and the IMAP service
- * crashes on 64-bit Linux.
- */
- if (flags & CTDLTHREAD_BIGSTACK)
- {
- CtdlLogPrintf(CTDL_INFO, "Thread system. Creating BIG STACK thread.\n");
- if ((ret = pthread_attr_setstacksize(&this_thread->attr, THREADSTACKSIZE))) {
- pthread_mutex_destroy(&(this_thread->ThreadMutex));
- pthread_cond_destroy(&(this_thread->ThreadCond));
- pthread_mutex_destroy(&(this_thread->SleepMutex));
- pthread_cond_destroy(&(this_thread->SleepCond));
- pthread_attr_destroy(&this_thread->attr);
- CtdlLogPrintf(CTDL_EMERG, "Thread system, pthread_attr_setstacksize: %s\n",
- strerror(ret));
- free(this_thread);
- return NULL;
- }
- }
- /*
- * If we got here we are going to create the thread so we must initilise the structure
- * first because most implimentations of threading can't create it in a stopped state
- * and it might want to do things with its structure that aren't initialised otherwise.
- */
- if(name)
- {
- this_thread->name = name;
- }
- else
- {
- this_thread->name = "Un-named Thread";
- }
-
- this_thread->flags = flags;
- this_thread->thread_func = thread_func;
- this_thread->user_args = args;
- /* Set this new thread with an avg_blocked of 2. We do this so that its creation affects the
- * load average for the system. If we don't do this then we create a mass of threads at the same time
- * because the creation didn't affect the load average.
- */
- this_thread->avg_blocked = 2;
-
- /*
- * When to start this thread
- */
- this_thread->when = when;
-
- begin_critical_section(S_SCHEDULE_LIST);
- this_thread->next = CtdlThreadSchedList;
- CtdlThreadSchedList = this_thread;
- if (this_thread->next)
- this_thread->next->prev = this_thread;
- end_critical_section(S_SCHEDULE_LIST);
-
- return this_thread;
-}
-
-
-
-struct CtdlThreadNode *ctdl_thread_internal_start_scheduled (struct CtdlThreadNode *this_thread)
-{
- int ret = 0;
-
- /*
- * We pass this_thread into the thread as its args so that it can find out information
- * about itself and it has a bit of storage space for itself, not to mention that the REAL
- * thread function needs to finish off the setup of the structure
- */
- if ((ret = pthread_create(&this_thread->tid, &this_thread->attr, ctdl_internal_thread_func, this_thread) != 0))
- {
-
- CtdlLogPrintf(CTDL_ALERT, "Thread system, Can't create thread: %s\n",
- strerror(ret));
- return NULL;
- }
-
-
- num_threads++; // Increase the count of threads in the system.
- if(this_thread->flags & CTDLTHREAD_WORKER)
- num_workers++;
-
- this_thread->next = CtdlThreadList;
- CtdlThreadList = this_thread;
- if (this_thread->next)
- this_thread->next->prev = this_thread;
-
- return this_thread;
-}
-
-
-
-void ctdl_thread_internal_check_scheduled(void)
-{
- struct CtdlThreadNode *this_thread, *that_thread;
- time_t now;
-
- if (try_critical_section(S_SCHEDULE_LIST))
- return; /* If this list is locked we wait till the next chance */
-
- now = time(NULL);
-
-#ifdef WITH_THREADLOG
- CtdlLogPrintf(CTDL_DEBUG, "Checking for scheduled threads to start.\n");
-#endif
-
- this_thread = CtdlThreadSchedList;
- while(this_thread)
- {
- that_thread = this_thread;
- this_thread = this_thread->next;
-
- if (now > that_thread->when)
- {
- /* Unlink from schedule list */
- if (that_thread->prev)
- that_thread->prev->next = that_thread->next;
- else
- CtdlThreadSchedList = that_thread->next;
- if (that_thread->next)
- that_thread->next->prev = that_thread->prev;
-
- that_thread->next = that_thread->prev = NULL;
-#ifdef WITH_THREADLOG
- CtdlLogPrintf(CTDL_DEBUG, "About to start scheduled thread \"%s\".\n", that_thread->name);
-#endif
- begin_critical_section(S_THREAD_LIST);
- if (CT->state > CTDL_THREAD_STOP_REQ)
- { /* Only start it if the system is not stopping */
- pthread_mutex_lock(&that_thread->ThreadMutex);
- if (ctdl_thread_internal_start_scheduled (that_thread) == NULL)
- {
-#ifdef WITH_THREADLOG
- CtdlLogPrintf(CTDL_DEBUG, "Failed to start scheduled thread \"%s\".\n", that_thread->name);
-#endif
- pthread_mutex_unlock(&that_thread->ThreadMutex);
- pthread_mutex_destroy(&(that_thread->ThreadMutex));
- pthread_cond_destroy(&(that_thread->ThreadCond));
- pthread_mutex_destroy(&(that_thread->SleepMutex));
- pthread_cond_destroy(&(that_thread->SleepCond));
- pthread_attr_destroy(&that_thread->attr);
- free(that_thread);
- }
- else
- {
- CtdlLogPrintf(CTDL_INFO, "Thread system, Started a scheduled thread \"%s\" (%ld).\n",
- that_thread->name, that_thread->tid);
- pthread_mutex_unlock(&that_thread->ThreadMutex);
- ctdl_thread_internal_calc_loadavg();
- }
- }
- end_critical_section(S_THREAD_LIST);
- }
- else
- {
-#ifdef WITH_THREADLOG
- CtdlLogPrintf(CTDL_DEBUG, "Thread \"%s\" will start in %ld seconds.\n", that_thread->name, that_thread->when - time(NULL));
-#endif
- }
- }
- end_critical_section(S_SCHEDULE_LIST);
+void InitializeMasterTSD(void) {
+ memset(&masterTSD, 0, sizeof(struct thread_tsd));
}
/*
- * A warapper function for select so we can show a thread as blocked
+ * Initialize the thread system
*/
-int CtdlThreadSelect(int n, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeout)
-{
- int ret;
-
- ctdl_thread_internal_change_state(CT, CTDL_THREAD_BLOCKED);
- ret = select(n, readfds, writefds, exceptfds, timeout);
- ctdl_thread_internal_change_state(CT, CTDL_THREAD_RUNNING);
- return ret;
-}
-
-
-
-
-
-
void go_threading(void)
{
- int i;
- struct CtdlThreadNode *last_worker;
-
- /*
- * Initialise the thread system
- */
- ctdl_thread_internal_init();
- /*
- * Now create a bunch of worker threads.
- */
-// CtdlLogPrintf(CTDL_DEBUG, "Starting %d worker threads\n", config.c_min_workers);
-// begin_critical_section(S_THREAD_LIST);
-// i=0; /* Always start at least 1 worker thread */
-// do
-// {
-// ctdl_internal_create_thread("Worker Thread", CTDLTHREAD_BIGSTACK + CTDLTHREAD_WORKER, worker_thread, NULL);
-// } while (++i < config.c_min_workers);
-// end_critical_section(S_THREAD_LIST);
+ pthread_mutex_init(&ThreadCountMutex, NULL);
/* Second call to module init functions now that threading is up */
initialise_modules(1);
- /*
- * This thread is now used for garbage collection of other threads in the thread list
- */
- CtdlLogPrintf(CTDL_INFO, "Startup thread %d becoming garbage collector,\n", pthread_self());
+ /* Begin with one worker thread. We will expand the pool if necessary */
+ CtdlThreadCreate(worker_thread);
- /*
- * We do a lot of locking and unlocking of the thread list in here.
- * We do this so that we can repeatedly release time for other threads
- * that may be waiting on the thread list.
- * We are a low priority thread so we can afford to do this
+ /* The supervisor thread monitors worker threads and spawns more of them if it finds that
+ * they are all in use.
*/
-
- while (CtdlThreadGetCount())
- {
- if (CT->signal)
- exit_signal = CT->signal;
- if (exit_signal)
- CtdlThreadStopAll();
- check_sched_shutdown();
- if (CT->state > CTDL_THREAD_STOP_REQ)
- {
- begin_critical_section(S_THREAD_LIST);
- ctdl_thread_internal_calc_loadavg();
- end_critical_section(S_THREAD_LIST);
-
- ctdl_thread_internal_check_scheduled(); /* start scheduled threads */
- }
-
- /* Reduce the size of the worker thread pool if necessary. */
- if ((CtdlThreadGetWorkers() > config.c_min_workers) && (CtdlThreadWorkerAvg < 20) && (CT->state > CTDL_THREAD_STOP_REQ))
- {
- /* Ask a worker thread to stop as we no longer need it */
- begin_critical_section(S_THREAD_LIST);
- last_worker = CtdlThreadList;
- while (last_worker)
- {
- pthread_mutex_lock(&last_worker->ThreadMutex);
- if (last_worker->flags & CTDLTHREAD_WORKER && last_worker->state > CTDL_THREAD_STOPPING)
- {
- pthread_mutex_unlock(&last_worker->ThreadMutex);
- break;
- }
- pthread_mutex_unlock(&last_worker->ThreadMutex);
- last_worker = last_worker->next;
- }
- end_critical_section(S_THREAD_LIST);
- if (last_worker)
- {
-#ifdef WITH_THREADLOG
- CtdlLogPrintf(CTDL_DEBUG, "Thread system, stopping excess worker thread \"%s\" (%ld).\n",
- last_worker->name,
- last_worker->tid
- );
-#endif
- CtdlThreadStop(last_worker);
- }
- }
-
- /*
- * If all our workers are working hard, start some more to help out
- * with things
- */
- /* FIXME: come up with a better way to dynamically alter the number of threads
- * based on the system load
- */
-// if ((CtdlThreadGetWorkers() < config.c_max_workers) && (CtdlThreadGetWorkers() < num_sessions))
- // && (CtdlThreadLoadAvg < 90) )
- if ((((CtdlThreadGetWorkers() < config.c_max_workers) && (CtdlThreadGetWorkerAvg() > 60) && (CtdlThreadGetLoadAvg() < 90) ) || CtdlThreadGetWorkers() < config.c_min_workers) && (CT->state > CTDL_THREAD_STOP_REQ))
- {
- for (i=0; i<5 ; i++)
-// for (i=0; i< (num_sessions - CtdlThreadGetWorkers()) ; i++)
-// for (i=0; i< (10 - (55 - CtdlThreadWorkerAvg) / CtdlThreadWorkerAvg / CtdlThreadGetWorkers()) ; i++)
- {
-// begin_critical_section(S_THREAD_LIST);
- CtdlThreadCreate("Worker Thread",
- CTDLTHREAD_BIGSTACK + CTDLTHREAD_WORKER,
- worker_thread,
- NULL
- );
-// end_critical_section(S_THREAD_LIST);
- }
+ while (!server_shutting_down) {
+ if ((active_workers == num_workers) && (num_workers < CtdlGetConfigInt("c_max_workers"))) {
+ CtdlThreadCreate(worker_thread);
}
-
- CtdlThreadGC();
-
- if (CtdlThreadGetCount() <= 1) // Shutting down clean up the garbage collector
- {
- CtdlThreadGC();
- }
-
- if (CtdlThreadGetCount())
- CtdlThreadSleep(1);
+ usleep(1000000);
}
- /*
- * If the above loop exits we must be shutting down since we obviously have no threads
+
+ /* When we get to this point we are getting ready to shut down our Citadel server */
+ terminate_all_sessions(); /* close all client sockets */
+ CtdlShutdownServiceHooks(); /* close all listener sockets to prevent new connections */
+ PerformSessionHooks(EVT_SHUTDOWN); /* run any registered shutdown hooks */
+
+ /* We used to wait for all threads to exit. Fuck that. The only thing important is that the databases are
+ * cleanly unmounted. After that, exit the whole program.
*/
- ctdl_thread_internal_cleanup();
+#if 0
+ int countdown = 30;
+ while ( (num_workers > 0) && (countdown-- > 0)) {
+ syslog(LOG_DEBUG, "Waiting %d seconds for %d worker threads to exit",
+ countdown, num_workers
+ );
+ usleep(1000000);
+ }
+#endif
+
}
projects / citadel.git / blobdiff