MDEV-17441 InnoDB transition to C++11 atomics

zip_pad_info_t::mutex_created: remove along with corresponding stuff

zip_pad_info_t::mutex: make member value instead of a pointer

storage/innobase/dict/dict0dict.cc

@@ -568,33 +568,6 @@ dict_table_get_nth_v_col_mysql(
 	return(dict_table_get_nth_v_col(table, i));
 }
 
-/** Allocate and init the zip_pad_mutex of a given index.
-This function must not be called concurrently on the same index object.
-@param[in,out]	index_void	index whose zip_pad_mutex to create */
-static
-void
-dict_index_zip_pad_alloc(
-	void*	index_void)
-{
-	dict_index_t*	index = static_cast<dict_index_t*>(index_void);
-	index->zip_pad.mutex = UT_NEW_NOKEY(SysMutex());
-	ut_a(index->zip_pad.mutex != NULL);
-	mutex_create(LATCH_ID_ZIP_PAD_MUTEX, index->zip_pad.mutex);
-}
-
-/** Acquire the zip_pad_mutex latch.
-@param[in,out]	index	the index whose zip_pad_mutex to acquire.*/
-static
-void
-dict_index_zip_pad_lock(
-	dict_index_t*	index)
-{
-	os_once::do_or_wait_for_done(
-		&index->zip_pad.mutex_created,
-		dict_index_zip_pad_alloc, index);
-
-	mutex_enter(index->zip_pad.mutex);
-}
 
 /** Get all the FTS indexes on a table.
 @param[in]	table	table
@@ -6453,10 +6426,10 @@ dict_index_zip_success(
 		return;
 	}
 
-	dict_index_zip_pad_lock(index);
+	mutex_enter(&index->zip_pad.mutex);
 	++index->zip_pad.success;
 	dict_index_zip_pad_update(&index->zip_pad, zip_threshold);
-	dict_index_zip_pad_unlock(index);
+	mutex_exit(&index->zip_pad.mutex);
 }
 
 /*********************************************************************//**
@@ -6473,10 +6446,10 @@ dict_index_zip_failure(
 		return;
 	}
 
-	dict_index_zip_pad_lock(index);
+	mutex_enter(&index->zip_pad.mutex);
 	++index->zip_pad.failure;
 	dict_index_zip_pad_update(&index->zip_pad, zip_threshold);
-	dict_index_zip_pad_unlock(index);
+	mutex_exit(&index->zip_pad.mutex);
 }
 
 /*********************************************************************//**

storage/innobase/dict/dict0mem.cc

@@ -740,7 +740,7 @@ dict_mem_index_create(
 
 	dict_mem_fill_index_struct(index, heap, index_name, type, n_fields);
 
-	dict_index_zip_pad_mutex_create_lazy(index);
+	mutex_create(LATCH_ID_ZIP_PAD_MUTEX, &index->zip_pad.mutex);
 
 	if (type & DICT_SPATIAL) {
 		mutex_create(LATCH_ID_RTR_SSN_MUTEX, &index->rtr_ssn.mutex);
@@ -1050,7 +1050,7 @@ dict_mem_index_free(
 	ut_ad(index);
 	ut_ad(index->magic_n == DICT_INDEX_MAGIC_N);
 
-	dict_index_zip_pad_mutex_destroy(index);
+	mutex_free(&index->zip_pad.mutex);
 
 	if (dict_index_is_spatial(index)) {
 		for (auto& rtr_info : index->rtr_track->rtr_active) {

storage/innobase/include/dict0mem.h

@@ -883,7 +883,7 @@ extern ulong	zip_pad_max;
 an uncompressed page should be left as padding to avoid compression
 failures. This estimate is based on a self-adapting heuristic. */
 struct zip_pad_info_t {
-	SysMutex*	mutex;	/*!< mutex protecting the info */
+	SysMutex	mutex;	/*!< mutex protecting the info */
 	Atomic_counter<ulint>
 			pad;	/*!< number of bytes used as pad */
 	ulint		success;/*!< successful compression ops during
@@ -892,9 +892,6 @@ struct zip_pad_info_t {
 				current round */
 	ulint		n_rounds;/*!< number of currently successful
 				rounds */
-	volatile os_once::state_t
-			mutex_created;
-				/*!< Creation state of mutex member */
 };
 
 /** Number of samples of data size kept when page compression fails for
@@ -2286,45 +2283,6 @@ struct dict_foreign_add_to_referenced_table {
 	}
 };
 
-/** Request a lazy creation of dict_index_t::zip_pad::mutex.
-This function is only called from either single threaded environment
-or from a thread that has not shared the table object with other threads.
-@param[in,out]	index	index whose zip_pad mutex is to be created */
-inline
-void
-dict_index_zip_pad_mutex_create_lazy(
-	dict_index_t*	index)
-{
-	index->zip_pad.mutex = NULL;
-	index->zip_pad.mutex_created = os_once::NEVER_DONE;
-}
-
-/** Destroy the zip_pad_mutex of the given index.
-This function is only called from either single threaded environment
-or from a thread that has not shared the table object with other threads.
-@param[in,out]	table	table whose stats latch to destroy */
-inline
-void
-dict_index_zip_pad_mutex_destroy(
-	dict_index_t*	index)
-{
-	if (index->zip_pad.mutex_created == os_once::DONE
-	    && index->zip_pad.mutex != NULL) {
-		mutex_free(index->zip_pad.mutex);
-		UT_DELETE(index->zip_pad.mutex);
-	}
-}
-
-/** Release the zip_pad_mutex of a given index.
-@param[in,out]	index	index whose zip_pad_mutex is to be released */
-inline
-void
-dict_index_zip_pad_unlock(
-	dict_index_t*	index)
-{
-	mutex_exit(index->zip_pad.mutex);
-}
-
 /** Check whether the col is used in spatial index or regular index.
 @param[in]	col	column to check
 @return spatial status */

storage/innobase/page/page0zip.cc

@@ -1602,7 +1602,7 @@ page_zip_fields_free(
 {
 	if (index) {
 		dict_table_t*	table = index->table;
-		dict_index_zip_pad_mutex_destroy(index);
+		mutex_free(&index->zip_pad.mutex);
 		mem_heap_free(index->heap);
 
 		dict_mem_table_free(table);