1 files changed, 44 insertions, 203 deletions

diff --git a/storage/xtradb/os/os0sync.cc b/storage/xtradb/os/os0sync.cc
index 03c53848832..1569fa7a865 100644
--- a/storage/xtradb/os/os0sync.cc
+++ b/storage/xtradb/os/os0sync.cc
@@ -47,27 +47,14 @@ struct os_mutex_t{
 				do not assume that the OS mutex
 				supports recursive locking, though
 				NT seems to do that */
-	UT_LIST_NODE_T(os_mutex_t) os_mutex_list;
-				/* list of all 'slow' OS mutexes created */
 };
 
-/** Mutex protecting counts and the lists of OS mutexes and events */
-UNIV_INTERN os_ib_mutex_t	os_sync_mutex;
-/** TRUE if os_sync_mutex has been initialized */
-static ibool		os_sync_mutex_inited	= FALSE;
-/** TRUE when os_sync_free() is being executed */
-static ibool		os_sync_free_called	= FALSE;
+// All the os_*_count variables are accessed atomically
 
 /** This is incremented by 1 in os_thread_create and decremented by 1 in
-os_thread_exit */
+os_thread_exit. */
 UNIV_INTERN ulint	os_thread_count		= 0;
 
-/** The list of all events created */
-static UT_LIST_BASE_NODE_T(os_event)		os_event_list;
-
-/** The list of all OS 'slow' mutexes */
-static UT_LIST_BASE_NODE_T(os_mutex_t)		os_mutex_list;
-
 UNIV_INTERN ulint	os_event_count		= 0;
 UNIV_INTERN ulint	os_mutex_count		= 0;
 UNIV_INTERN ulint	os_fast_mutex_count	= 0;
@@ -80,11 +67,6 @@ UNIV_INTERN mysql_pfs_key_t	event_os_mutex_key;
 UNIV_INTERN mysql_pfs_key_t	os_mutex_key;
 #endif
 
-/* Because a mutex is embedded inside an event and there is an
-event embedded inside a mutex, on free, this generates a recursive call.
-This version of the free event function doesn't acquire the global lock */
-static void os_event_free_internal(os_event_t	event);
-
 /* On Windows (Vista and later), load function pointers for condition
 variable handling. Those functions are not available in prior versions,
 so we have to use them via runtime loading, as long as we support XP. */
@@ -289,74 +271,21 @@ void
 os_sync_init(void)
 /*==============*/
 {
-	UT_LIST_INIT(os_event_list);
-	UT_LIST_INIT(os_mutex_list);
-
-	os_sync_mutex = NULL;
-	os_sync_mutex_inited = FALSE;
-
 	/* Now for Windows only */
 	os_cond_module_init();
-
-	os_sync_mutex = os_mutex_create();
-
-	os_sync_mutex_inited = TRUE;
 }
 
-/*********************************************************//**
-Frees created events and OS 'slow' mutexes. */
+/** Create an event semaphore, i.e., a semaphore which may just have two
+states: signaled and nonsignaled. The created event is manual reset: it must be
+reset explicitly by calling sync_os_reset_event.
+@param[in,out]	event	memory block where to create the event */
 UNIV_INTERN
 void
-os_sync_free(void)
-/*==============*/
-{
-	os_event_t	event;
-	os_ib_mutex_t	mutex;
-
-	os_sync_free_called = TRUE;
-	event = UT_LIST_GET_FIRST(os_event_list);
-
-	while (event) {
-
-		os_event_free(event);
-
-		event = UT_LIST_GET_FIRST(os_event_list);
-	}
-
-	mutex = UT_LIST_GET_FIRST(os_mutex_list);
-
-	while (mutex) {
-		if (mutex == os_sync_mutex) {
-			/* Set the flag to FALSE so that we do not try to
-			reserve os_sync_mutex any more in remaining freeing
-			operations in shutdown */
-			os_sync_mutex_inited = FALSE;
-		}
-
-		os_mutex_free(mutex);
-
-		mutex = UT_LIST_GET_FIRST(os_mutex_list);
-	}
-	os_sync_free_called = FALSE;
-}
-
-/*********************************************************//**
-Creates an event semaphore, i.e., a semaphore which may just have two
-states: signaled and nonsignaled. The created event is manual reset: it
-must be reset explicitly by calling sync_os_reset_event.
-@return	the event handle */
-UNIV_INTERN
-os_event_t
-os_event_create(void)
-/*==================*/
+os_event_create(os_event_t event)
 {
-	os_event_t	event;
-
 #ifdef __WIN__
 	if(!srv_use_native_conditions) {
 
-		event = static_cast<os_event_t>(ut_malloc(sizeof(*event)));
-
 		event->handle = CreateEvent(NULL, TRUE, FALSE, NULL);
 		if (!event->handle) {
 			fprintf(stderr,
@@ -367,8 +296,6 @@ os_event_create(void)
 	} else /* Windows with condition variables */
 #endif
 	{
-		event = static_cast<os_event_t>(ut_malloc(sizeof *event));
-
 #ifndef PFS_SKIP_EVENT_MUTEX
 		os_fast_mutex_init(event_os_mutex_key, &event->os_mutex);
 #else
@@ -377,32 +304,25 @@ os_event_create(void)
 
 		os_cond_init(&(event->cond_var));
 
-		event->is_set = FALSE;
-
-		/* We return this value in os_event_reset(), which can then be
-		be used to pass to the os_event_wait_low(). The value of zero
-		is reserved in os_event_wait_low() for the case when the
-		caller does not want to pass any signal_count value. To
-		distinguish between the two cases we initialize signal_count
-		to 1 here. */
-		event->signal_count = 1;
+		event->init_count_and_set();
 	}
 
-	/* The os_sync_mutex can be NULL because during startup an event
-	can be created [ because it's embedded in the mutex/rwlock ] before
-	this module has been initialized */
-	if (os_sync_mutex != NULL) {
-		os_mutex_enter(os_sync_mutex);
-	}
-
-	/* Put to the list of events */
-	UT_LIST_ADD_FIRST(os_event_list, os_event_list, event);
+	os_atomic_increment_ulint(&os_event_count, 1);
+}
 
-	os_event_count++;
+/*********************************************************//**
+Creates an event semaphore, i.e., a semaphore which may just have two
+states: signaled and nonsignaled. The created event is manual reset: it
+must be reset explicitly by calling sync_os_reset_event.
+@return	the event handle */
+UNIV_INTERN
+os_event_t
+os_event_create(void)
+/*==================*/
+{
+	os_event_t event = static_cast<os_event_t>(ut_malloc(sizeof(*event)));;
 
-	if (os_sync_mutex != NULL) {
-		os_mutex_exit(os_sync_mutex);
-	}
+	os_event_create(event);
 
 	return(event);
 }
@@ -427,11 +347,11 @@ os_event_set(
 
 	os_fast_mutex_lock(&(event->os_mutex));
 
-	if (event->is_set) {
+	if (UNIV_UNLIKELY(event->is_set())) {
 		/* Do nothing */
 	} else {
-		event->is_set = TRUE;
-		event->signal_count += 1;
+		event->set();
+		event->inc_signal_count();
 		os_cond_broadcast(&(event->cond_var));
 	}
 
@@ -465,55 +385,26 @@ os_event_reset(
 
 	os_fast_mutex_lock(&(event->os_mutex));
 
-	if (!event->is_set) {
+	if (UNIV_UNLIKELY(!event->is_set())) {
 		/* Do nothing */
 	} else {
-		event->is_set = FALSE;
+		event->reset();
 	}
-	ret = event->signal_count;
+	ret = event->signal_count();
 
 	os_fast_mutex_unlock(&(event->os_mutex));
 	return(ret);
 }
 
 /**********************************************************//**
-Frees an event object, without acquiring the global lock. */
-static
-void
-os_event_free_internal(
-/*===================*/
-	os_event_t	event)	/*!< in: event to free */
-{
-#ifdef __WIN__
-	if(!srv_use_native_conditions) {
-		ut_a(event);
-		ut_a(CloseHandle(event->handle));
-	} else
-#endif
-	{
-		ut_a(event);
-
-		/* This is to avoid freeing the mutex twice */
-		os_fast_mutex_free(&(event->os_mutex));
-
-		os_cond_destroy(&(event->cond_var));
-	}
-
-	/* Remove from the list of events */
-	UT_LIST_REMOVE(os_event_list, os_event_list, event);
-
-	os_event_count--;
-
-	ut_free(event);
-}
-
-/**********************************************************//**
 Frees an event object. */
 UNIV_INTERN
 void
 os_event_free(
 /*==========*/
-	os_event_t	event)	/*!< in: event to free */
+	os_event_t	event,	/*!< in: event to free */
+	bool		free_memory)/*!< in: if true, deallocate the event
+				    memory block too */
 
 {
 	ut_a(event);
@@ -528,16 +419,10 @@ os_event_free(
 		os_cond_destroy(&(event->cond_var));
 	}
 
-	/* Remove from the list of events */
-	os_mutex_enter(os_sync_mutex);
+	os_atomic_decrement_ulint(&os_event_count, 1);
 
-	UT_LIST_REMOVE(os_event_list, os_event_list, event);
-
-	os_event_count--;
-
-	os_mutex_exit(os_sync_mutex);
-
-	ut_free(event);
+	if (free_memory)
+		ut_free(event);
 }
 
 /**********************************************************//**
@@ -585,10 +470,10 @@ os_event_wait_low(
 	os_fast_mutex_lock(&event->os_mutex);
 
 	if (!reset_sig_count) {
-		reset_sig_count = event->signal_count;
+		reset_sig_count = event->signal_count();
 	}
 
-	while (!event->is_set && event->signal_count == reset_sig_count) {
+	while (!event->is_set() && event->signal_count() == reset_sig_count) {
 		os_cond_wait(&(event->cond_var), &(event->os_mutex));
 
 		/* Solaris manual said that spurious wakeups may occur: we
@@ -686,11 +571,12 @@ os_event_wait_time_low(
 	os_fast_mutex_lock(&event->os_mutex);
 
 	if (!reset_sig_count) {
-		reset_sig_count = event->signal_count;
+		reset_sig_count = event->signal_count();
 	}
 
 	do {
-		if (event->is_set || event->signal_count != reset_sig_count) {
+		if (event->is_set()
+		    || event->signal_count() != reset_sig_count) {
 
 			break;
 		}
@@ -734,18 +620,7 @@ os_mutex_create(void)
 	mutex_str->count = 0;
 	mutex_str->event = os_event_create();
 
-	if (UNIV_LIKELY(os_sync_mutex_inited)) {
-		/* When creating os_sync_mutex itself we cannot reserve it */
-		os_mutex_enter(os_sync_mutex);
-	}
-
-	UT_LIST_ADD_FIRST(os_mutex_list, os_mutex_list, mutex_str);
-
-	os_mutex_count++;
-
-	if (UNIV_LIKELY(os_sync_mutex_inited)) {
-		os_mutex_exit(os_sync_mutex);
-	}
+	os_atomic_increment_ulint(&os_mutex_count, 1);
 
 	return(mutex_str);
 }
@@ -791,21 +666,9 @@ os_mutex_free(
 {
 	ut_a(mutex);
 
-	if (UNIV_LIKELY(!os_sync_free_called)) {
-		os_event_free_internal(mutex->event);
-	}
-
-	if (UNIV_LIKELY(os_sync_mutex_inited)) {
-		os_mutex_enter(os_sync_mutex);
-	}
-
-	UT_LIST_REMOVE(os_mutex_list, os_mutex_list, mutex);
+	os_event_free(mutex->event);
 
-	os_mutex_count--;
-
-	if (UNIV_LIKELY(os_sync_mutex_inited)) {
-		os_mutex_exit(os_sync_mutex);
-	}
+	os_atomic_decrement_ulint(&os_mutex_count, 1);
 
 	os_fast_mutex_free(static_cast<os_fast_mutex_t*>(mutex->handle));
 	ut_free(mutex->handle);
@@ -827,18 +690,7 @@ os_fast_mutex_init_func(
 #else
 	ut_a(0 == pthread_mutex_init(fast_mutex, MY_MUTEX_INIT_FAST));
 #endif
-	if (UNIV_LIKELY(os_sync_mutex_inited)) {
-		/* When creating os_sync_mutex itself (in Unix) we cannot
-		reserve it */
-
-		os_mutex_enter(os_sync_mutex);
-	}
-
-	os_fast_mutex_count++;
-
-	if (UNIV_LIKELY(os_sync_mutex_inited)) {
-		os_mutex_exit(os_sync_mutex);
-	}
+	os_atomic_increment_ulint(&os_fast_mutex_count, 1);
 }
 
 /**********************************************************//**
@@ -919,17 +771,6 @@ os_fast_mutex_free_func(
 		putc('\n', stderr);
 	}
 #endif
-	if (UNIV_LIKELY(os_sync_mutex_inited)) {
-		/* When freeing the last mutexes, we have
-		already freed os_sync_mutex */
-
-		os_mutex_enter(os_sync_mutex);
-	}
 
-	ut_ad(os_fast_mutex_count > 0);
-	os_fast_mutex_count--;
-
-	if (UNIV_LIKELY(os_sync_mutex_inited)) {
-		os_mutex_exit(os_sync_mutex);
-	}
+	os_atomic_decrement_ulint(&os_fast_mutex_count, 1);
 }