MDEV-12534 Use atomic operations whenever available

Allow 64-bit atomic operations on 32-bit systems,
only relying on HAVE_ATOMIC_BUILTINS_64, disregarding
the width of the register file.

Define UNIV_WORD_SIZE correctly on all systems, including Windows.
In MariaDB 10.0 and 10.1, it was incorrectly defined as 4 on
64-bit Windows.

Define HAVE_ATOMIC_BUILTINS_64 on Windows
(64-bit atomics are available on both 32-bit and 64-bit Windows
platforms; the operations were unnecessarily disabled even on
64-bit Windows).

MONITOR_OS_PENDING_READS, MONITOR_OS_PENDING_WRITES: Enable by default.

os_file_n_pending_preads, os_file_n_pending_pwrites,
os_n_pending_reads, os_n_pending_writes: Remove.
Use the monitor counters instead.

os_file_count_mutex: Remove. On a system that does not support
64-bit atomics, monitor_mutex will be used instead.

4 files changed, 50 insertions, 41 deletions

diff --git a/storage/innobase/include/os0file.h b/storage/innobase/include/os0file.h
index 6cb4f54d629..bdb4682eafb 100644
--- a/storage/innobase/include/os0file.h
+++ b/storage/innobase/include/os0file.h
@@ -2,7 +2,7 @@
 
 Copyright (c) 1995, 2016, Oracle and/or its affiliates. All Rights Reserved.
 Copyright (c) 2009, Percona Inc.
-Copyright (c) 2017, MariaDB Corporation. All Rights Reserved.
+Copyright (c) 2013, 2017, MariaDB Corporation.
 
 Portions of this file contain modifications contributed and copyrighted
 by Percona Inc.. Those modifications are
@@ -51,16 +51,6 @@ extern ibool	os_has_said_disk_full;
 /** Flag: enable debug printout for asynchronous i/o */
 extern ibool	os_aio_print_debug;
 
-/** Number of pending os_file_pread() operations */
-extern ulint	os_file_n_pending_preads;
-/** Number of pending os_file_pwrite() operations */
-extern ulint	os_file_n_pending_pwrites;
-
-/** Number of pending read operations */
-extern ulint	os_n_pending_reads;
-/** Number of pending write operations */
-extern ulint	os_n_pending_writes;
-
 #ifdef __WIN__
 
 /** We define always WIN_ASYNC_IO, and check at run-time whether
diff --git a/storage/innobase/include/os0sync.h b/storage/innobase/include/os0sync.h
index 0754210c47a..dd6de43dc0b 100644
--- a/storage/innobase/include/os0sync.h
+++ b/storage/innobase/include/os0sync.h
@@ -667,10 +667,7 @@ os_atomic_clear(volatile lock_word_t* ptr)
 
 # define HAVE_ATOMIC_BUILTINS
 # define HAVE_ATOMIC_BUILTINS_BYTE
-
-# ifndef _WIN32
-#  define HAVE_ATOMIC_BUILTINS_64
-# endif
+# define HAVE_ATOMIC_BUILTINS_64
 
 /**********************************************************//**
 Atomic compare and exchange of signed integers (both 32 and 64 bit).
diff --git a/storage/innobase/include/srv0mon.h b/storage/innobase/include/srv0mon.h
index 2d90f47eefe..09af5d4159b 100644
--- a/storage/innobase/include/srv0mon.h
+++ b/storage/innobase/include/srv0mon.h
@@ -2,6 +2,7 @@
 
 Copyright (c) 2010, 2013, Oracle and/or its affiliates. All Rights Reserved.
 Copyright (c) 2012, Facebook Inc.
+Copyright (c) 2017, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it
 under the terms of the GNU General Public License as published by the
@@ -541,22 +542,30 @@ on the counters */
 
 /** Increment a monitor counter under mutex protection.
 Use MONITOR_INC if appropriate mutex protection already exists.
+@param mutex	mutex to acquire and release
 @param monitor	monitor to be incremented by 1
-@param mutex	mutex to acquire and relese */
-# define MONITOR_MUTEX_INC(mutex, monitor)				\
+@param enabled	whether the monitor is enabled */
+#define MONITOR_MUTEX_INC_LOW(mutex, monitor, enabled)			\
 	ut_ad(!mutex_own(mutex));					\
-	if (MONITOR_IS_ON(monitor)) {					\
+	if (enabled) {							\
 		mutex_enter(mutex);					\
 		if (++MONITOR_VALUE(monitor) > MONITOR_MAX_VALUE(monitor)) { \
 			MONITOR_MAX_VALUE(monitor) = MONITOR_VALUE(monitor); \
 		}							\
 		mutex_exit(mutex);					\
 	}
+/** Increment a monitor counter under mutex protection.
+Use MONITOR_INC if appropriate mutex protection already exists.
+@param mutex	mutex to acquire and release
+@param monitor	monitor to be incremented by 1 */
+#define MONITOR_MUTEX_INC(mutex, monitor)				\
+	MONITOR_MUTEX_INC_LOW(mutex, monitor, MONITOR_IS_ON(monitor))
 /** Decrement a monitor counter under mutex protection.
 Use MONITOR_DEC if appropriate mutex protection already exists.
+@param mutex	mutex to acquire and release
 @param monitor	monitor to be decremented by 1
-@param mutex	mutex to acquire and relese */
-# define MONITOR_MUTEX_DEC(mutex, monitor)				\
+@param enabled	whether the monitor is enabled */
+#define MONITOR_MUTEX_DEC_LOW(mutex, monitor, enabled)			\
 	ut_ad(!mutex_own(mutex));					\
 	if (MONITOR_IS_ON(monitor)) {					\
 		mutex_enter(mutex);					\
@@ -565,13 +574,20 @@ Use MONITOR_DEC if appropriate mutex protection already exists.
 		}							\
 		mutex_exit(mutex);					\
 	}
+/** Decrement a monitor counter under mutex protection.
+Use MONITOR_DEC if appropriate mutex protection already exists.
+@param mutex	mutex to acquire and release
+@param monitor	monitor to be decremented by 1 */
+#define MONITOR_MUTEX_DEC(mutex, monitor)				\
+	MONITOR_MUTEX_DEC_LOW(mutex, monitor, MONITOR_IS_ON(monitor))
 
 #if defined HAVE_ATOMIC_BUILTINS_64
 /** Atomically increment a monitor counter.
 Use MONITOR_INC if appropriate mutex protection exists.
-@param monitor	monitor to be incremented by 1 */
-# define MONITOR_ATOMIC_INC(monitor)					\
-	if (MONITOR_IS_ON(monitor)) {					\
+@param monitor	monitor to be incremented by 1
+@param enabled	whether the monitor is enabled */
+# define MONITOR_ATOMIC_INC_LOW(monitor, enabled)			\
+	if (enabled) {					\
 		ib_uint64_t	value;					\
 		value  = os_atomic_increment_uint64(			\
 			(ib_uint64_t*) &MONITOR_VALUE(monitor),	 1);	\
@@ -584,9 +600,10 @@ Use MONITOR_INC if appropriate mutex protection exists.
 
 /** Atomically decrement a monitor counter.
 Use MONITOR_DEC if appropriate mutex protection exists.
-@param monitor	monitor to be decremented by 1 */
-# define MONITOR_ATOMIC_DEC(monitor)					\
-	if (MONITOR_IS_ON(monitor)) {					\
+@param monitor	monitor to be decremented by 1
+@param enabled	whether the monitor is enabled */
+# define MONITOR_ATOMIC_DEC_LOW(monitor, enabled)			\
+	if (enabled) {							\
 		ib_uint64_t	value;					\
 		value = os_atomic_decrement_uint64(			\
 			(ib_uint64_t*) &MONITOR_VALUE(monitor), 1);	\
@@ -617,14 +634,29 @@ srv_mon_free(void);
 
 /** Atomically increment a monitor counter.
 Use MONITOR_INC if appropriate mutex protection exists.
-@param monitor	monitor to be incremented by 1 */
-# define MONITOR_ATOMIC_INC(monitor) MONITOR_MUTEX_INC(&monitor_mutex, monitor)
+@param monitor	monitor to be incremented by 1
+@param enabled	whether the monitor is enabled */
+# define MONITOR_ATOMIC_INC_LOW(monitor, enabled)		\
+	MONITOR_MUTEX_INC_LOW(&monitor_mutex, monitor, enabled)
 /** Atomically decrement a monitor counter.
 Use MONITOR_DEC if appropriate mutex protection exists.
-@param monitor	monitor to be decremented by 1 */
-# define MONITOR_ATOMIC_DEC(monitor) MONITOR_MUTEX_DEC(&monitor_mutex, monitor)
+@param monitor	monitor to be decremented by 1
+@param enabled	whether the monitor is enabled */
+# define MONITOR_ATOMIC_DEC_LOW(monitor, enabled)		\
+	MONITOR_MUTEX_DEC_LOW(&monitor_mutex, monitor, enabled)
 #endif /* HAVE_ATOMIC_BUILTINS_64 */
 
+/** Atomically increment a monitor counter if it is enabled.
+Use MONITOR_INC if appropriate mutex protection exists.
+@param monitor	monitor to be incremented by 1 */
+#define MONITOR_ATOMIC_INC(monitor)				\
+	MONITOR_ATOMIC_INC_LOW(monitor, MONITOR_IS_ON(monitor))
+/** Atomically decrement a monitor counter if it is enabled.
+Use MONITOR_DEC if appropriate mutex protection exists.
+@param monitor	monitor to be decremented by 1 */
+#define MONITOR_ATOMIC_DEC(monitor)				\
+	MONITOR_ATOMIC_DEC_LOW(monitor, MONITOR_IS_ON(monitor))
+
 #define	MONITOR_DEC(monitor)						\
 	if (MONITOR_IS_ON(monitor)) {					\
 		MONITOR_VALUE(monitor)--;				\
diff --git a/storage/innobase/include/univ.i b/storage/innobase/include/univ.i
index 824a06829f9..fc0bf0aeeca 100644
--- a/storage/innobase/include/univ.i
+++ b/storage/innobase/include/univ.i
@@ -285,22 +285,12 @@ definitions: */
 
 #endif /* !UNIV_MUST_NOT_INLINE */
 
-#ifdef _WIN32
-#define UNIV_WORD_SIZE		4
-#elif defined(_WIN64)
-#define UNIV_WORD_SIZE		8
-#else
-/** MySQL config.h generated by GNU autoconf will define SIZEOF_LONG in Posix */
-#define UNIV_WORD_SIZE		SIZEOF_LONG
-#endif
+#define UNIV_WORD_SIZE		SIZEOF_SIZE_T
 
 /** The following alignment is used in memory allocations in memory heap
 management to ensure correct alignment for doubles etc. */
 #define UNIV_MEM_ALIGNMENT	8
 
-/** The following alignment is used in aligning lints etc. */
-#define UNIV_WORD_ALIGNMENT	UNIV_WORD_SIZE
-
 /*
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