static RETSIGTYPE signal_cleanup(int signum) {
CtdlLogPrintf(CTDL_DEBUG, "Caught signal %d; shutting down.\n", signum);
- CtdlThreadStopAll();
exit_signal = signum;
}
}
+
+/*
+ * Obtain a semaphore lock to begin a critical section.
+ * but only if no one else has one
+ */
+int try_critical_section(int 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)
+ ) {
+ cdb_check_handles();
+ }
+ return (pthread_mutex_trylock(&Critters[which_one]));
+}
+
+
/*
* Obtain a semaphore lock to begin a critical section.
*/
* There are no threads so no critical_section stuff is needed.
*/
ptr = ContextList;
+
+ /* We need to update the ContextList because some modules may want to itterate it
+ * Question is should we NULL it before iterating here or should we just keep updating it
+ * as we remove items?
+ *
+ * Answer is to NULL it first to prevent modules from doing any actions on the list at all
+ */
+ ContextList=NULL;
while (ptr != NULL){
/* Remove the session from the active list */
rem = ptr->next;
free (ptr);
ptr = rem;
}
-
}
CtdlDestroyFixedOutputHooks();
CtdlDestroySessionHooks();
CtdlDestroyServiceHook();
+ CtdlDestroyRoomHooks();
+ CtdlDestroyDirectoryServiceFuncs();
#ifdef HAVE_BACKTRACE
eCrash_Uninit();
#endif
* 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.
- * If your thread function returns it will be started again without creating a new thread.
- * If your thread function wants to exit it should call CtdlThreadExit(ret_code);
* 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
*/
struct CtdlThreadNode *CtdlThreadList = NULL;
+struct CtdlThreadNode *CtdlThreadSchedList = NULL;
/*
* Condition variable and Mutex for thread garbage collection
static char *CtdlThreadStates[CTDL_THREAD_LAST_STATE];
double CtdlThreadLoadAvg = 0;
double CtdlThreadWorkerAvg = 0;
+pthread_key_t ThreadKey;
+
/*
- * Pinched the following bits regarding signals from Kannel.org
+ * A function to destroy the TSD
*/
-
+static void ctdl_thread_internal_dest_tsd(void *arg)
+{
+ if (arg != NULL) {
+ check_handles(arg);
+ free(arg);
+ }
+}
+
+
/*
- * Change this thread's signal mask to block user-visible signals
- * (HUP, TERM, QUIT, INT), and store the old signal mask in
- * *old_set_storage.
- * Return 0 for success, or -1 if an error occurred.
+ * A function to initialise the thread TSD
*/
-
- /*
- * This does not work in Darwin alias MacOS X alias Mach kernel,
- * however. So we define a dummy function doing nothing.
- */
-#if defined(DARWIN_OLD)
- static int pthread_sigmask();
-#endif
-
-static int ctdl_thread_internal_block_signals(sigset_t *old_set_storage)
+void ctdl_thread_internal_init_tsd(void)
{
- int ret;
- sigset_t block_signals;
-
- ret = sigemptyset(&block_signals);
- if (ret != 0) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC. Couldn't initialize signal set\n");
- return -1;
- }
- ret = sigaddset(&block_signals, SIGHUP);
- ret |= sigaddset(&block_signals, SIGTERM);
- ret |= sigaddset(&block_signals, SIGQUIT);
- ret |= sigaddset(&block_signals, SIGINT);
- if (ret != 0) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC. Couldn't add signal to signal set.\n");
- return -1;
- }
- ret = pthread_sigmask(SIG_BLOCK, &block_signals, old_set_storage);
- if (ret != 0) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC. Couldn't disable signals for thread creation\n");
- return -1;
- }
- return 0;
-}
-
-static void ctdl_thread_internal_restore_signals(sigset_t *old_set)
+ 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)
{
- int ret;
+ ThreadTSD *tsd;
+
+ if (pthread_getspecific(ThreadKey) != NULL)
+ return;
+
+ tsd = malloc(sizeof(ThreadTSD));
- ret = pthread_sigmask(SIG_SETMASK, old_set, NULL);
- if (ret != 0) {
- CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC. Couldn't restore signal set.\n");
- }
+ 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)
// 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;
return;
}
- this_thread->name = strdup("Garbage Collection Thread");
-
- pthread_mutex_init (&(this_thread->ThreadMutex), NULL);
- pthread_cond_init (&(this_thread->ThreadCond), NULL);
+ this_thread->name = "Garbage Collection Thread";
this_thread->tid = GC_thread;
+ CT = this_thread;
num_threads++; // Increase the count of threads in the system.
struct timeval now, result;
double last_duration;
- pthread_mutex_lock(&this_thread->ThreadMutex); /* To prevent race condition of a sleeping thread */
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)
*/
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)
{
- if (this_thread->thread_func) // Don't tell garbage collector to stop
- {
- ctdl_thread_internal_change_state (this_thread, CTDL_THREAD_STOP_REQ);
- pthread_cond_signal(&this_thread->ThreadCond);
- CtdlLogPrintf(CTDL_DEBUG, "Thread system stopping thread \"%s\" (%ld).\n", this_thread->name, this_thread->tid);
- }
+ 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 signal that we need to do garbage collection on the thread list
+ * A function to wake up all sleeping threads
*/
-void CtdlThreadGC(void)
+void CtdlThreadWakeAll(void)
{
struct CtdlThreadNode *this_thread;
- CtdlLogPrintf(CTDL_DEBUG, "Thread system signalling garbage collection.\n");
+ 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);
*/
int CtdlThreadGetCount(void)
{
- return num_threads;
+ int ret;
+
+ begin_critical_section(S_THREAD_LIST);
+ ret = num_threads;
+ end_critical_section(S_THREAD_LIST);
+ return ret;
}
-/*
- * A function to find the thread structure for this thread
- */
-struct CtdlThreadNode *CtdlThreadSelf(void)
+int CtdlThreadGetWorkers(void)
{
- pthread_t self_tid;
- struct CtdlThreadNode *this_thread;
+ int ret;
- self_tid = pthread_self();
+ begin_critical_section(S_THREAD_LIST);
+ ret = num_workers;
+ end_critical_section(S_THREAD_LIST);
+ return ret;
+}
+
+double CtdlThreadGetWorkerAvg(void)
+{
+ double ret;
begin_critical_section(S_THREAD_LIST);
- this_thread = CtdlThreadList;
- while(this_thread)
- {
- if (pthread_equal(self_tid, this_thread->tid))
- {
- end_critical_section(S_THREAD_LIST);
- return this_thread;
- }
- this_thread = this_thread->next;
- }
+ 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 NULL;
+ return ret;
}
/*
* A function to rename a thread
- * Returns a char * and the caller owns the memory and should free it
+ * Returns a const char *
*/
-char *CtdlThreadName(struct CtdlThreadNode *thread, char *name)
+const char *CtdlThreadName(const char *name)
{
- struct CtdlThreadNode *this_thread;
- char *old_name;
+ const char *old_name;
- if (!thread)
- this_thread = CtdlThreadSelf();
- else
- this_thread = thread;
- if (!this_thread)
+ if (!CT)
{
- CtdlLogPrintf(CTDL_WARNING, "Thread system WARNING. Attempt to CtdlThreadRename() a non thread.\n");
+ CtdlLogPrintf(CTDL_WARNING, "Thread system WARNING. Attempt to CtdlThreadRename() a non thread. %s\n", name);
return NULL;
}
- begin_critical_section(S_THREAD_LIST);
+ pthread_mutex_lock(&CT->ThreadMutex);
+ old_name = CT->name;
if (name)
- {
- old_name = this_thread->name;
- this_thread->name = strdup (name);
- free(old_name);
- }
- old_name = strdup(this_thread->name);
- end_critical_section (S_THREAD_LIST);
+ CT->name = name;
+ pthread_mutex_unlock(&CT->ThreadMutex);
return (old_name);
}
struct CtdlThreadNode *this_thread;
if (!thread)
- this_thread = CtdlThreadSelf();
+ this_thread = CT;
else
this_thread = thread;
if (!this_thread)
return;
}
- begin_critical_section(S_THREAD_LIST);
ctdl_thread_internal_change_state (this_thread, CTDL_THREAD_CANCELLED);
pthread_cancel(this_thread->tid);
- end_critical_section (S_THREAD_LIST);
}
*/
int CtdlThreadCheckStop(void)
{
- struct CtdlThreadNode *this_thread;
-
- this_thread = CtdlThreadSelf();
- if (!this_thread)
+ if (!CT)
{
CtdlLogPrintf(CTDL_EMERG, "Thread system PANIC, CtdlThreadCheckStop() called by a non thread.\n");
CtdlThreadStopAll();
return -1;
}
- if(this_thread->state == CTDL_THREAD_STOP_REQ)
+ pthread_mutex_lock(&CT->ThreadMutex);
+ if(CT->state == CTDL_THREAD_STOP_REQ)
{
- this_thread->state = CTDL_THREAD_STOPPING;
+ CT->state = CTDL_THREAD_STOPPING;
+ pthread_mutex_unlock(&CT->ThreadMutex);
return -1;
}
- else if(this_thread->state < CTDL_THREAD_STOP_REQ)
+ else if((CT->state < CTDL_THREAD_STOP_REQ) && (CT->state > CTDL_THREAD_CREATE))
+ {
+ pthread_mutex_unlock(&CT->ThreadMutex);
return -1;
-
+ }
+ pthread_mutex_unlock(&CT->ThreadMutex);
return 0;
}
struct CtdlThreadNode *this_thread;
if (!thread)
- this_thread = CtdlThreadSelf();
+ this_thread = CT;
else
this_thread = thread;
if (!this_thread)
if (!(this_thread->thread_func))
return; // Don't stop garbage collector
- begin_critical_section (S_THREAD_LIST);
ctdl_thread_internal_change_state (this_thread, CTDL_THREAD_STOP_REQ);
pthread_cond_signal(&this_thread->ThreadCond);
- end_critical_section(S_THREAD_LIST);
+ pthread_cond_signal(&this_thread->SleepCond);
}
/*
{
struct timespec wake_time;
struct timeval time_now;
- struct CtdlThreadNode *self;
- self = CtdlThreadSelf();
- if (!self)
+ if (!CT)
{
CtdlLogPrintf(CTDL_WARNING, "CtdlThreadSleep() called by something that is not a thread. Should we die?\n");
return;
}
- begin_critical_section(S_THREAD_LIST);
- ctdl_thread_internal_change_state (self, CTDL_THREAD_SLEEPING);
- pthread_mutex_lock(&self->ThreadMutex); /* Prevent something asking us to awaken before we've gone to sleep */
- end_critical_section(S_THREAD_LIST);
-
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;
- pthread_cond_timedwait(&self->ThreadCond, &self->ThreadMutex, &wake_time);
- begin_critical_section(S_THREAD_LIST);
- pthread_mutex_unlock(&self->ThreadMutex);
- ctdl_thread_internal_change_state (self, CTDL_THREAD_RUNNING);
- end_critical_section(S_THREAD_LIST);
+
+ 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);
}
*/
static void ctdl_internal_thread_cleanup(void *arg)
{
- struct CtdlThreadNode *this_thread;
- this_thread = CtdlThreadSelf();
/*
* 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", this_thread->name, this_thread->tid);
- begin_critical_section(S_THREAD_LIST);
+ CtdlLogPrintf(CTDL_NOTICE, "Thread \"%s\" (%ld) exited.\n", CT->name, CT->tid);
+
#ifdef HAVE_BACKTRACE
eCrash_UnregisterThread();
#endif
- this_thread->state = CTDL_THREAD_EXITED; // needs to be last thing else house keeping will unlink us too early
- end_critical_section(S_THREAD_LIST);
-// CtdlThreadGC();
+
+ 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);
}
/*
double load_avg, worker_avg;
int workers = 0;
- begin_critical_section(S_THREAD_LIST);
that_thread = CtdlThreadList;
load_avg = 0;
worker_avg = 0;
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,
that_thread->avg_running,
that_thread->avg_blocked,
that_thread->load_avg);
-
+#endif
pthread_mutex_unlock(&that_thread->ThreadMutex);
that_thread = that_thread->next;
}
CtdlThreadLoadAvg = load_avg/num_threads;
CtdlThreadWorkerAvg = worker_avg/workers;
- CtdlLogPrintf(CTDL_INFO, "System load average %f, workers averag %f\n", CtdlThreadLoadAvg, CtdlThreadWorkerAvg);
- end_critical_section(S_THREAD_LIST);
+#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
}
* Garbage collection routine.
* Gets called by main() in a loop to clean up the thread list periodically.
*/
-void ctdl_internal_thread_gc (void)
+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
*/
- begin_critical_section(S_THREAD_LIST);
this_thread = CtdlThreadList;
while(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");
- CtdlThreadStopAll();
+ abort();
return;
}
if (num_threads <= 0)
{ /* Sanity check */
- end_critical_section (S_THREAD_LIST);
+ 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");
- CtdlThreadStopAll();
+ 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 == CtdlThreadList)
- CtdlThreadList = that_thread->next;
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->next;
- num_threads--;
- if(that_thread->flags & CTDLTHREAD_WORKER)
- num_workers--; /* This is a wroker thread so reduce the count. */
+ 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
- * If that thread has no function it must be the garbage collector
+ * We can join on the garbage collector thread the join should just return EDEADLCK
*/
- if (that_thread->thread_func)
- pthread_join (that_thread->tid, NULL);
-
+ 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);
- if(that_thread->name)
- free(that_thread->name);
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);
}
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);
- return;
+ 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);
}
* can continue its execution.
*/
begin_critical_section(S_THREAD_LIST);
- // Get our thread data structure
this_thread = (struct CtdlThreadNode *) arg;
- this_thread->state = CTDL_THREAD_RUNNING;
- this_thread->pid = getpid();
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. */
- end_critical_section(S_THREAD_LIST);
+ /* 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);
- // Register the cleanup function to take care of when we exit.
- pthread_cleanup_push(ctdl_internal_thread_cleanup, NULL);
/*
- * run the thread to do the work
+ * run the thread to do the work but only if we haven't been asked to stop
*/
- ret = (this_thread->thread_func)(this_thread->user_args);
+ 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
{
int ret = 0;
struct CtdlThreadNode *this_thread;
- int sigtrick = 0;
- sigset_t old_signal_set;
if (num_threads >= 32767)
{
// 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;
{
CtdlLogPrintf(CTDL_INFO, "Thread system. Creating BIG STACK thread.\n");
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));
- pthread_attr_destroy(&this_thread->attr);
free(this_thread);
return NULL;
}
*/
if(name)
{
- this_thread->name = strdup(name);
+ this_thread->name = name;
}
else
{
- this_thread->name = strdup("Un-named Thread");
+ this_thread->name = "Un-named Thread";
}
this_thread->flags = flags;
this_thread->thread_func = thread_func;
this_thread->user_args = args;
- pthread_mutex_init (&(this_thread->ThreadMutex), NULL);
- pthread_cond_init (&(this_thread->ThreadCond), NULL);
-
- /*
- * We want to make sure that only the main thread handles signals,
- * so that each signal is handled exactly once. To do this, we
- * make sure that each new thread has all the signals that we
- * handle blocked. To avoid race conditions, we block them in
- * the spawning thread first, then create the new thread (which
- * inherits the settings), and then restore the old settings in
- * the spawning thread. This means that there is a brief period
- * when no signals will be processed, but during that time they
- * should be queued by the operating system.
+ /* 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.
*/
- if (pthread_equal(GC_thread, pthread_self()))
- sigtrick = ctdl_thread_internal_block_signals(&old_signal_set) == 0;
-
+ 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
CtdlLogPrintf(CTDL_ALERT, "Thread system, Can't create thread: %s\n",
strerror(ret));
- if (this_thread->name)
- free (this_thread->name);
+ 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);
- if (sigtrick)
- ctdl_thread_internal_restore_signals(&old_signal_set);
return NULL;
}
- if (sigtrick)
- ctdl_thread_internal_restore_signals(&old_signal_set);
-
num_threads++; // Increase the count of threads in the system.
if(this_thread->flags & CTDLTHREAD_WORKER)
num_workers++;
CtdlThreadList = this_thread;
if (this_thread->next)
this_thread->next->prev = this_thread;
- // Register for tracing
- #ifdef HAVE_BACKTRACE
- eCrash_RegisterThread(this_thread->name, 0);
- #endif
+
+ pthread_mutex_unlock(&this_thread->ThreadMutex);
+
+ ctdl_thread_internal_calc_loadavg();
return this_thread;
}
+/*
+ * 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);
+}
+
+
/*
* A warapper function for select so we can show a thread as blocked
*/
-int CtdlThreadSelect(int n, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, const struct timeval *timeout)
+int CtdlThreadSelect(int n, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeout, struct CtdlThreadNode *self)
{
- struct CtdlThreadNode *self;
int ret;
- self = CtdlThreadSelf();
ctdl_thread_internal_change_state(self, CTDL_THREAD_BLOCKED);
ret = select(n, readfds, writefds, exceptfds, timeout);
ctdl_thread_internal_change_state(self, CTDL_THREAD_RUNNING);
* few seconds, because running it after every single unbind would waste a lot
* of CPU time and keep the context list locked too much. To force it to run
* anyway, set "force" to nonzero.
- *
- *
- * After that's done, we raise the size of the worker thread pool
- * if such an action is appropriate.
*/
void dead_session_purge(int force) {
struct CitContext *ptr, *ptr2; /* general-purpose utility pointer */
struct CitContext *rem = NULL; /* list of sessions to be destroyed */
-
+
if (force == 0) {
if ( (time(NULL) - last_purge) < 5 ) {
return; /* Too soon, go away */
}
time(&last_purge);
- begin_critical_section(S_SESSION_TABLE);
+ if (try_critical_section(S_SESSION_TABLE))
+ return;
+
ptr = ContextList;
while (ptr) {
ptr2 = ptr;
}
--num_sessions;
-
/* And put it on our to-be-destroyed list */
ptr2->next = rem;
rem = ptr2;
-
}
}
end_critical_section(S_SESSION_TABLE);
rem = rem->next;
free(ptr);
}
-
- /* Raise the size of the worker thread pool if necessary. */
- begin_critical_section(S_THREAD_LIST);
- if ( (num_sessions > num_workers)
- && (num_workers < config.c_max_workers) ) {
- ctdl_internal_create_thread("Worker Thread", CTDLTHREAD_BIGSTACK + CTDLTHREAD_WORKER, worker_thread, NULL);
- }
- end_critical_section(S_THREAD_LIST);
- // FIXME: reduce the number of worker threads too
}
struct timeval tv;
int force_purge = 0;
int m;
-
- cdb_allocate_tsd();
+
while (!CtdlThreadCheckStop()) {
if (!CtdlThreadCheckStop()) {
tv.tv_sec = 1; /* wake up every second if no input */
tv.tv_usec = 0;
- retval = CtdlThreadSelect(highest + 1, &readfds, NULL, NULL, &tv);
-// retval = select(highest + 1, &readfds, NULL, NULL, &tv);
+ retval = CtdlThreadSelect(highest + 1, &readfds, NULL, NULL, &tv, CT);
}
if (CtdlThreadCheckStop()) return(NULL);
dead_session_purge(force_purge);
do_housekeeping();
- check_sched_shutdown();
}
/* If control reaches this point, the server is shutting down */
return(NULL);