Fix bug 1578139 (Parallel doublewrite memory not freed with innodb_fa…

…st_shutdown=2)

With a very fast InnoDB shutdown, buf_parallel_dblwr_destroy(), which
closes and deletes the doublewrite file and frees memory, is skipped.
In this configuration the file should not be deleted, thus fix by
renaming buf_parallel_dblwr_destroy() to buf_parallel_dblwr_free()
that unconditionally frees memory and, depending on the arg value,
closes and deletes the file. Call it in the common code path for all
innodb_fast_shutdown values.

storage/innobase/buf/buf0dblwr.cc

@@ -1524,7 +1524,7 @@ buf_parallel_dblwr_file_create(void)
 	success = os_file_set_size(parallel_dblwr_buf.path,
 				   parallel_dblwr_buf.file, size, false);
 	if (!success) {
-		buf_parallel_dblwr_destroy();
+		buf_parallel_dblwr_free(true);
 		return(DB_ERROR);
 	}
 	ut_ad(os_file_get_size(parallel_dblwr_buf.file) == size);
@@ -1567,7 +1567,7 @@ buf_parallel_dblwr_create(void)
 						       * UNIV_PAGE_SIZE,
 					mem_key_parallel_doublewrite));
 		if (!dblwr_shard->write_buf_unaligned) {
-			buf_parallel_dblwr_destroy();
+			buf_parallel_dblwr_free(true);
 			return(DB_OUT_OF_MEMORY);
 		}
 		dblwr_shard->write_buf = static_cast<byte*>(
@@ -1579,7 +1579,7 @@ buf_parallel_dblwr_create(void)
 				  * sizeof(void*),
 				  mem_key_parallel_doublewrite));
 		if (!dblwr_shard->buf_block_arr) {
-			buf_parallel_dblwr_destroy();
+			buf_parallel_dblwr_free(true);
 			return(DB_OUT_OF_MEMORY);
 		}
 
@@ -1591,10 +1591,11 @@ buf_parallel_dblwr_create(void)
 	return(DB_SUCCESS);
 }
 
-/** Close and delete the doublewrite buffer file and free its memory data
-structure. */
+/** Cleanup parallel doublewrite memory structures and optionally close and
+delete the doublewrite buffer file too.
+@param	delete_file	whether to close and delete the buffer file too  */
 void
-buf_parallel_dblwr_destroy(void)
+buf_parallel_dblwr_free(bool delete_file)
 {
 	for (ulint i = 0; i < buf_parallel_dblwr_shard_num(); i++) {
 
@@ -1610,8 +1611,10 @@ buf_parallel_dblwr_destroy(void)
 		ut_free(dblwr_shard->buf_block_arr);
 	}
 
-	buf_parallel_dblwr_close();
-	buf_parallel_dblwr_delete();
+	if (delete_file) {
+		buf_parallel_dblwr_close();
+		buf_parallel_dblwr_delete();
+	}
 
 	ut_free(parallel_dblwr_buf.path);
 	parallel_dblwr_buf.path = NULL;

storage/innobase/include/buf0dblwr.h

@@ -161,10 +161,11 @@ computed. It is up to the caller to ensure that this called at safe point */
 void
 buf_parallel_dblwr_delete(void);
 
-/** Close and delete the doublewrite buffer file and free its memory data
-structure. */
+/** Cleanup parallel doublewrite memory structures and optionally close and
+delete the doublewrite buffer file too.
+@param	delete_file	whether to close and delete the buffer file too  */
 void
-buf_parallel_dblwr_destroy(void);
+buf_parallel_dblwr_free(bool delete_file);
 
 /** Release any unused parallel doublewrite pages and free their underlying
 buffer at the end of crash recovery */

storage/innobase/log/log0log.cc

@@ -2405,8 +2405,6 @@ logs_empty_and_mark_files_at_shutdown(void)
 		fil_write_flushed_lsn(lsn);
 	}
 
-	buf_parallel_dblwr_destroy();
-
 	fil_close_all_files();
 
 	/* Make some checks that the server really is quiet */

storage/innobase/trx/trx0sys.cc

@@ -1164,6 +1164,7 @@ trx_sys_close(void)
 
 	/* Free the double write data structures. */
 	buf_dblwr_free();
+	buf_parallel_dblwr_free(srv_fast_shutdown != 2);
 
 	/* Only prepared transactions may be left in the system. Free them. */
 	ut_a(UT_LIST_GET_LEN(trx_sys->rw_trx_list) == trx_sys->n_prepared_trx);