Google SMP patch

storage/innobase/btr/btr0cur.c

@@ -333,7 +333,7 @@ btr_cur_search_to_nth_level(
 #ifdef UNIV_SEARCH_PERF_STAT
 	info->n_searches++;
 #endif
-	if (btr_search_latch.writer == RW_LOCK_NOT_LOCKED
+	if (rw_lock_get_writer(&btr_search_latch) == RW_LOCK_NOT_LOCKED
 	    && latch_mode <= BTR_MODIFY_LEAF && info->last_hash_succ
 	    && !estimate
 #ifdef PAGE_CUR_LE_OR_EXTENDS

storage/innobase/btr/btr0sea.c

@@ -748,8 +748,8 @@ btr_search_guess_on_hash(
 		rw_lock_s_lock(&btr_search_latch);
 	}
 
-	ut_ad(btr_search_latch.writer != RW_LOCK_EX);
-	ut_ad(btr_search_latch.reader_count > 0);
+	ut_ad(rw_lock_get_writer(&btr_search_latch) != RW_LOCK_EX);
+	ut_ad(rw_lock_get_reader_count(&btr_search_latch) > 0);
 
 	rec = ha_search_and_get_data(btr_search_sys->hash_index, fold);
 

storage/innobase/buf/buf0buf.c

@@ -1277,8 +1277,8 @@ buf_page_get_gen(
 
 	if (mode == BUF_GET_NOWAIT) {
 		if (rw_latch == RW_S_LATCH) {
-			success = rw_lock_s_lock_func_nowait(&(block->lock),
-							     file, line);
+			success = rw_lock_s_lock_nowait(&(block->lock),
+							file, line);
 			fix_type = MTR_MEMO_PAGE_S_FIX;
 		} else {
 			ut_ad(rw_latch == RW_X_LATCH);
@@ -1403,8 +1403,8 @@ buf_page_optimistic_get_func(
 	ut_ad(!ibuf_inside() || ibuf_page(block->space, block->offset));
 
 	if (rw_latch == RW_S_LATCH) {
-		success = rw_lock_s_lock_func_nowait(&(block->lock),
-						     file, line);
+		success = rw_lock_s_lock_nowait(&(block->lock),
+						file, line);
 		fix_type = MTR_MEMO_PAGE_S_FIX;
 	} else {
 		success = rw_lock_x_lock_func_nowait(&(block->lock),
@@ -1534,8 +1534,8 @@ buf_page_get_known_nowait(
 	ut_ad(!ibuf_inside() || (mode == BUF_KEEP_OLD));
 
 	if (rw_latch == RW_S_LATCH) {
-		success = rw_lock_s_lock_func_nowait(&(block->lock),
-						     file, line);
+		success = rw_lock_s_lock_nowait(&(block->lock),
+						file, line);
 		fix_type = MTR_MEMO_PAGE_S_FIX;
 	} else {
 		success = rw_lock_x_lock_func_nowait(&(block->lock),

storage/innobase/handler/ha_innodb.cc

@@ -374,6 +374,10 @@ static SHOW_VAR innodb_status_variables[]= {
   (char*) &export_vars.innodb_dblwr_pages_written,	  SHOW_LONG},
   {"dblwr_writes",
   (char*) &export_vars.innodb_dblwr_writes,		  SHOW_LONG},
+  {"have_atomic_builtins",
+  (char*) &export_vars.innodb_have_atomic_builtins,	  SHOW_BOOL},
+  {"heap_enabled",
+  (char*) &export_vars.innodb_heap_enabled,		  SHOW_BOOL},
   {"log_waits",
   (char*) &export_vars.innodb_log_waits,		  SHOW_LONG},
   {"log_write_requests",
@@ -6878,6 +6882,7 @@ innodb_mutex_show_status(
 {
 	char buf1[IO_SIZE], buf2[IO_SIZE];
 	mutex_t*  mutex;
+	rw_lock_t* lock;
 #ifdef UNIV_DEBUG
 	ulint	  rw_lock_count= 0;
 	ulint	  rw_lock_count_spin_loop= 0;
@@ -6948,6 +6953,31 @@ innodb_mutex_show_status(
 
 	mutex_exit_noninline(&mutex_list_mutex);
 
+	mutex_enter_noninline(&rw_lock_list_mutex);
+
+	lock = UT_LIST_GET_FIRST(rw_lock_list);
+
+	while (lock != NULL)
+	{
+		if (lock->count_os_wait)
+		{
+			buf1len= my_snprintf(buf1, sizeof(buf1), "%s:%lu",
+                                    lock->cfile_name, (ulong) lock->cline);
+			buf2len= my_snprintf(buf2, sizeof(buf2),
+                                    "os_waits=%lu", lock->count_os_wait);
+
+			if (stat_print(thd, innobase_hton_name,
+				       hton_name_len, buf1, buf1len,
+				       buf2, buf2len)) {
+				mutex_exit_noninline(&rw_lock_list_mutex);
+				DBUG_RETURN(1);
+			}
+		}
+		lock = UT_LIST_GET_NEXT(list, lock);
+	}
+
+	mutex_exit_noninline(&rw_lock_list_mutex);
+
 #ifdef UNIV_DEBUG
 	buf2len= my_snprintf(buf2, sizeof(buf2),
 		"count=%lu, spin_waits=%lu, spin_rounds=%lu, "
@@ -6980,6 +7010,7 @@ bool innobase_show_status(handlerton *hton, THD* thd,
 		return FALSE;
 	}
 }
+	rw_lock_t* lock;
 
 
 /****************************************************************************

storage/innobase/include/buf0buf.ic

@@ -513,7 +513,7 @@ buf_block_buf_fix_inc_debug(
 {
 	ibool	ret;
 
-	ret = rw_lock_s_lock_func_nowait(&(block->debug_latch), file, line);
+	ret = rw_lock_s_lock_nowait(&(block->debug_latch), file, line);
 
 	ut_ad(ret == TRUE);
 	ut_ad(mutex_own(&block->mutex));

storage/innobase/include/os0sync.h

@@ -261,6 +261,29 @@ os_fast_mutex_free(
 /*===============*/
 	os_fast_mutex_t*	fast_mutex);	/* in: mutex to free */
 
+#ifdef HAVE_GCC_ATOMIC_BUILTINS
+/**************************************************************
+Atomic compare-and-swap for InnoDB. Currently requires GCC atomic builtins. */
+UNIV_INLINE
+ibool
+os_compare_and_swap(
+/*================*/
+						/* out: true if swapped */
+	volatile lint*		ptr,		/* in: pointer to target */
+	lint			oldVal,		/* in: value to compare to */
+	lint			newVal);	/* in: value to swap in */
+/**************************************************************
+Atomic increment for InnoDB. Currently requires GCC atomic builtins. */
+UNIV_INLINE
+lint
+os_atomic_increment(
+/*================*/
+						/* out: resulting value */
+	volatile lint*		ptr,		/* in: pointer to target */
+	lint			amount);	/* in: amount of increment */
+
+#endif /* HAVE_GCC_ATOMIC_BUILTINS */
+
 #ifndef UNIV_NONINL
 #include "os0sync.ic"
 #endif

storage/innobase/include/os0sync.ic

@@ -44,3 +44,38 @@ os_fast_mutex_trylock(
 #endif
 #endif
 }
+
+#ifdef HAVE_GCC_ATOMIC_BUILTINS
+/**************************************************************
+Atomic compare-and-swap for InnoDB. Currently requires GCC atomic builtins. */
+UNIV_INLINE
+ibool
+os_compare_and_swap(
+/*================*/
+					/* out: true if swapped */
+	volatile lint* 	ptr,		/* in: pointer to target */
+	lint		oldVal,		/* in: value to compare to */
+	lint		newVal)		/* in: value to swap in */
+{
+	if(__sync_bool_compare_and_swap(ptr, oldVal, newVal)) {
+		return(TRUE);
+	}
+
+	return(FALSE);
+}
+
+/**************************************************************
+Atomic increment for InnoDB. Currently requires GCC atomic builtins. */
+UNIV_INLINE
+lint
+os_atomic_increment(
+/*================*/
+					/* out: resulting value */
+	volatile lint*	ptr,		/* in: pointer to target */
+	lint		amount)		/* in: amount of increment */
+{
+	lint newVal = __sync_add_and_fetch(ptr, amount);
+	return newVal;
+}
+
+#endif /* HAVE_GCC_ATOMIC_BUILTINS */

storage/innobase/include/srv0srv.h

@@ -513,6 +513,8 @@ struct export_var_struct{
 	ulint innodb_buffer_pool_read_ahead_rnd;
 	ulint innodb_dblwr_pages_written;
 	ulint innodb_dblwr_writes;
+	ibool innodb_have_atomic_builtins;
+	ibool innodb_heap_enabled;
 	ulint innodb_log_waits;
 	ulint innodb_log_write_requests;
 	ulint innodb_log_writes;
@@ -549,4 +551,3 @@ struct srv_sys_struct{
 extern ulint	srv_n_threads_active[];
 
 #endif
-

storage/innobase/include/sync0rw.h

@@ -24,6 +24,12 @@ smaller than 30 and the order of the numerical values like below! */
 #define	RW_X_LATCH	2
 #define	RW_NO_LATCH	3
 
+/* We decrement lock_word by this amount for each x_lock. It is also the
+start value for the lock_word, meaning that it limits the maximum number
+of concurrent read locks before the rw_lock breaks. The current value of
+0x00100000 allows 1,048,575 concurrent readers and 2047 recursive writers.*/
+#define X_LOCK_DECR		0x00100000
+
 typedef struct rw_lock_struct		rw_lock_t;
 #ifdef UNIV_SYNC_DEBUG
 typedef struct rw_lock_debug_struct	rw_lock_debug_t;
@@ -47,14 +53,14 @@ extern ibool		rw_lock_debug_waiters;	/* This is set to TRUE, if
 					there may be waiters for the event */
 #endif /* UNIV_SYNC_DEBUG */
 
-extern	ulint	rw_s_system_call_count;
-extern	ulint	rw_s_spin_wait_count;
-extern	ulint	rw_s_exit_count;
-extern	ulint	rw_s_os_wait_count;
-extern	ulint	rw_x_system_call_count;
-extern	ulint	rw_x_spin_wait_count;
-extern	ulint	rw_x_os_wait_count;
-extern	ulint	rw_x_exit_count;
+extern	ib_longlong	rw_s_spin_wait_count;
+extern	ib_longlong	rw_s_spin_round_count;
+extern	ib_longlong	rw_s_exit_count;
+extern	ib_longlong	rw_s_os_wait_count;
+extern	ib_longlong	rw_x_spin_wait_count;
+extern	ib_longlong	rw_x_spin_round_count;
+extern	ib_longlong	rw_x_os_wait_count;
+extern	ib_longlong	rw_x_exit_count;
 
 /**********************************************************************
 Creates, or rather, initializes an rw-lock object in a specified memory
@@ -127,8 +133,8 @@ corresponding function. */
 NOTE! The following macros should be used in rw s-locking, not the
 corresponding function. */
 
-#define rw_lock_s_lock_nowait(M)	rw_lock_s_lock_func_nowait(\
-		(M), __FILE__, __LINE__)
+#define rw_lock_s_lock_nowait(M, F, L)    rw_lock_s_lock_low(\
+					  (M), 0, (F), (L))
 /**********************************************************************
 NOTE! Use the corresponding macro, not directly this function, except if
 you supply the file name and line number. Lock an rw-lock in shared mode
@@ -146,18 +152,6 @@ rw_lock_s_lock_func(
 	const char*	file_name,/* in: file name where lock requested */
 	ulint		line);	/* in: line where requested */
 /**********************************************************************
-NOTE! Use the corresponding macro, not directly this function, except if
-you supply the file name and line number. Lock an rw-lock in shared mode
-for the current thread if the lock can be acquired immediately. */
-UNIV_INLINE
-ibool
-rw_lock_s_lock_func_nowait(
-/*=======================*/
-				/* out: TRUE if success */
-	rw_lock_t*	lock,	/* in: pointer to rw-lock */
-	const char*	file_name,/* in: file name where lock requested */
-	ulint		line);	/* in: line where requested */
-/**********************************************************************
 NOTE! Use the corresponding macro, not directly this function! Lock an
 rw-lock in exclusive mode for the current thread if the lock can be
 obtained immediately. */
@@ -341,6 +335,23 @@ ulint
 rw_lock_get_reader_count(
 /*=====================*/
 	rw_lock_t*	lock);
+/**********************************************************************
+Decrements lock_word the specified amount if it is greater than 0.
+This is used by both s_lock and x_lock operations. */
+UNIV_INLINE
+ibool
+rw_lock_lock_word_decr(
+					/* out: TRUE if decr occurs */
+	rw_lock_t*	lock,		/* in: rw-lock */
+	ulint		amount);	/* in: amount to decrement */
+/**********************************************************************
+Increments lock_word the specified amount and returns new value. */
+UNIV_INLINE
+lint
+rw_lock_lock_word_incr(
+					/* out: TRUE if decr occurs */
+	rw_lock_t*	lock,
+	ulint		amount);	/* in: rw-lock */
 #ifdef UNIV_SYNC_DEBUG
 /**********************************************************************
 Checks if the thread has locked the rw-lock in the specified mode, with
@@ -417,44 +428,28 @@ Do not use its fields directly! The structure used in the spin lock
 implementation of a read-write lock. Several threads may have a shared lock
 simultaneously in this lock, but only one writer may have an exclusive lock,
 in which case no shared locks are allowed. To prevent starving of a writer
-blocked by readers, a writer may queue for the lock by setting the writer
-field. Then no new readers are allowed in. */
+blocked by readers, a writer may queue for x-lock by decrementing lock_word:
+no new readers will be let in while the thread waits for readers to exit. */
 
 struct rw_lock_struct {
-	os_event_t	event;	/* Used by sync0arr.c for thread queueing */
-
-#ifdef __WIN__
-	os_event_t	wait_ex_event;	/* This windows specific event is
-				used by the thread which has set the
-				lock state to RW_LOCK_WAIT_EX. The
-				rw_lock design guarantees that this
-				thread will be the next one to proceed
-				once the current the event gets
-				signalled. See LEMMA 2 in sync0sync.c */
-#endif
-
-	ulint	reader_count;	/* Number of readers who have locked this
-				lock in the shared mode */
-	ulint	writer;		/* This field is set to RW_LOCK_EX if there
-				is a writer owning the lock (in exclusive
-				mode), RW_LOCK_WAIT_EX if a writer is
-				queueing for the lock, and
-				RW_LOCK_NOT_LOCKED, otherwise. */
-	os_thread_id_t	writer_thread;
-				/* Thread id of a possible writer thread */
-	ulint	writer_count;	/* Number of times the same thread has
-				recursively locked the lock in the exclusive
-				mode */
-	mutex_t	mutex;		/* The mutex protecting rw_lock_struct */
-	ulint	pass;		/* Default value 0. This is set to some
+	volatile lint	lock_word;
+				/* Holds the state of the lock. */
+	volatile ulint	waiters;/* 1: there are waiters */
+	volatile ulint	pass;	/* Default value 0. This is set to some
 				value != 0 given by the caller of an x-lock
 				operation, if the x-lock is to be passed to
 				another thread to unlock (which happens in
 				asynchronous i/o). */
-	ulint	waiters;	/* This ulint is set to 1 if there are
-				waiters (readers or writers) in the global
-				wait array, waiting for this rw_lock.
-				Otherwise, == 0. */
+	volatile os_thread_id_t	writer_thread;
+				/* Thread id of writer thread */
+	os_event_t	event;	/* Used by sync0arr.c for thread queueing */
+	os_event_t	wait_ex_event;
+				/* Event for next-writer to wait on. A thread
+				must decrement lock_word before waiting. */
+#ifndef HAVE_GCC_ATOMIC_BUILTINS
+	mutex_t	mutex;		/* The mutex protecting rw_lock_struct */
+#endif /* HAVE_GCC_ATOMIC_BUILTINS */
+
 	UT_LIST_NODE_T(rw_lock_t) list;
 				/* All allocated rw locks are put into a
 				list */
@@ -464,7 +459,9 @@ struct rw_lock_struct {
 				info list of the lock */
 	ulint	level;		/* Level in the global latching order. */
 #endif /* UNIV_SYNC_DEBUG */
+	ulint count_os_wait;	/* Count of os_waits. May not be accurate */
 	const char*	cfile_name;/* File name where lock created */
+        /* last s-lock file/line is not guaranteed to be correct */
 	const char*	last_s_file_name;/* File name where last s-locked */
 	const char*	last_x_file_name;/* File name where last x-locked */
 	ibool		writer_is_wait_ex;

storage/innobase/include/sync0sync.h

@@ -252,7 +252,7 @@ mutex_n_reserved(void);
 NOT to be used outside this module except in debugging! Gets the value
 of the lock word. */
 UNIV_INLINE
-ulint
+byte
 mutex_get_lock_word(
 /*================*/
 	const mutex_t*	mutex);	/* in: mutex */
@@ -471,9 +471,13 @@ implementation of a mutual exclusion semaphore. */
 
 struct mutex_struct {
 	os_event_t	event;	/* Used by sync0arr.c for the wait queue */
-	ulint	lock_word;	/* This ulint is the target of the atomic
-				test-and-set instruction in Win32 */
-#if !defined(_WIN32) || !defined(UNIV_CAN_USE_X86_ASSEMBLER)
+
+ 	byte	lock_word;	/* This byte is the target of the atomic
+ 				test-and-set instruction in Win32 and
+ 				x86 32/64 with GCC 4.1.0 or later version */
+#if defined(_WIN32) && defined(UNIV_CAN_USE_X86_ASSEMBLER)
+#elif defined(HAVE_GCC_ATOMIC_BUILTINS)
+#else
 	os_fast_mutex_t
 		os_fast_mutex;	/* In other systems we use this OS mutex
 				in place of lock_word */
@@ -526,8 +530,7 @@ to 20 microseconds. */
 /* The number of system calls made in this module. Intended for performance
 monitoring. */
 
-extern	ulint	mutex_system_call_count;
-extern	ulint	mutex_exit_count;
+extern	ib_longlong	mutex_exit_count;
 
 #ifdef UNIV_SYNC_DEBUG
 /* Latching order checks start when this is set TRUE */

storage/innobase/include/sync0sync.ic

@@ -6,16 +6,6 @@ Mutex, the basic synchronization primitive
 Created 9/5/1995 Heikki Tuuri
 *******************************************************/
 
-#if defined(not_defined) && defined(__GNUC__) && defined(UNIV_INTEL_X86)
-/* %z0: Use the size of operand %0 which in our case is *m to determine
-instruction size, it should end up as xchgl. "1" in the input constraint,
-says that "in" has to go in the same place as "out".*/
-#define TAS(m, in, out) \
-	asm volatile ("xchg%z0 %2, %0" \
-	: "=g" (*(m)), "=r" (out) \
-	: "1" (in))	/* Note: "1" here refers to "=r" (out) */
-#endif
-
 /**********************************************************************
 Sets the waiters field in a mutex. */
 
@@ -59,7 +49,7 @@ mutex_signal_object(
 Performs an atomic test-and-set instruction to the lock_word field of a
 mutex. */
 UNIV_INLINE
-ulint
+byte
 mutex_test_and_set(
 /*===============*/
 				/* out: the previous value of lock_word: 0 or
@@ -67,18 +57,18 @@ mutex_test_and_set(
 	mutex_t*	mutex)	/* in: mutex */
 {
 #if defined(_WIN32) && defined(UNIV_CAN_USE_X86_ASSEMBLER)
-	ulint	res;
-	ulint*	lw;		/* assembler code is used to ensure that
+	byte	res;
+	byte*	lw;		/* assembler code is used to ensure that
 				lock_word is loaded from memory */
 	ut_ad(mutex);
-	ut_ad(sizeof(ulint) == 4);
+	ut_ad(sizeof(byte) == 1);
 
 	lw = &(mutex->lock_word);
 
 	__asm	MOV	ECX, lw
 		__asm	MOV	EDX, 1
-		__asm	XCHG	EDX, DWORD PTR [ECX]
-		__asm	MOV	res, EDX
+		__asm	XCHG	DL, BYTE PTR [ECX]
+		__asm	MOV	res, DL
 
 		/* The fence below would prevent this thread from
 		reading the data structure protected by the mutex
@@ -98,12 +88,8 @@ mutex_test_and_set(
 		/* mutex_fence(); */
 
 		return(res);
-#elif defined(not_defined) && defined(__GNUC__) && defined(UNIV_INTEL_X86)
-	ulint	res;
-
-	TAS(&mutex->lock_word, 1, res);
-
-	return(res);
+#elif defined(HAVE_GCC_ATOMIC_BUILTINS)
+	return __sync_lock_test_and_set(&(mutex->lock_word), 1);
 #else
 	ibool	ret;
 
@@ -117,7 +103,7 @@ mutex_test_and_set(
 		mutex->lock_word = 1;
 	}
 
-	return(ret);
+	return((byte)ret);
 #endif
 }
 
@@ -131,7 +117,7 @@ mutex_reset_lock_word(
 	mutex_t*	mutex)	/* in: mutex */
 {
 #if defined(_WIN32) && defined(UNIV_CAN_USE_X86_ASSEMBLER)
-	ulint*	lw;		/* assembler code is used to ensure that
+	byte*	lw;		/* assembler code is used to ensure that
 				lock_word is loaded from memory */
 	ut_ad(mutex);
 
@@ -139,11 +125,12 @@ mutex_reset_lock_word(
 
 	__asm	MOV	EDX, 0
 		__asm	MOV	ECX, lw
-		__asm	XCHG	EDX, DWORD PTR [ECX]
-#elif defined(not_defined) && defined(__GNUC__) && defined(UNIV_INTEL_X86)
-	ulint	res;
-
-	TAS(&mutex->lock_word, 0, res);
+		__asm	XCHG	DL, BYTE PTR [ECX]
+#elif defined(HAVE_GCC_ATOMIC_BUILTINS)
+	/* In theory __sync_lock_release should be used to release the lock.
+	Unfortunately, it does not work properly alone. The workaround is
+	that more conservative __sync_lock_test_and_set is used instead. */
+	__sync_lock_test_and_set(&(mutex->lock_word), 0);
 #else
 	mutex->lock_word = 0;
 
@@ -154,12 +141,12 @@ mutex_reset_lock_word(
 /**********************************************************************
 Gets the value of the lock word. */
 UNIV_INLINE
-ulint
+byte
 mutex_get_lock_word(
 /*================*/
 	const mutex_t*	mutex)	/* in: mutex */
 {
-	const volatile ulint*	ptr;	/* declared volatile to ensure that
+	const volatile byte*	ptr;	/* declared volatile to ensure that
 					lock_word is loaded from memory */
 	ut_ad(mutex);
 

storage/innobase/include/univ.i

@@ -116,6 +116,9 @@ by one. */
 #define UNIV_SET_MEM_TO_ZERO
 #endif
 
+/* Use malloc instead of innodb additional memory pool (great with tcmalloc) */
+#define UNIV_DISABLE_MEM_POOL
+
 /*
 #define UNIV_SQL_DEBUG
 #define UNIV_LOG_DEBUG

storage/innobase/mem/mem0pool.c

@@ -329,6 +329,9 @@ mem_area_alloc(
 				minus MEM_AREA_EXTRA_SIZE */
 	mem_pool_t*	pool)	/* in: memory pool */
 {
+#ifdef UNIV_DISABLE_MEM_POOL
+        return malloc(size);
+#else /* UNIV_DISABLE_MEM_POOL */
 	mem_area_t*	area;
 	ulint		n;
 	ibool		ret;
@@ -407,6 +410,7 @@ mem_area_alloc(
 		       ut_2_exp(n) - MEM_AREA_EXTRA_SIZE);
 
 	return((void*)(MEM_AREA_EXTRA_SIZE + ((byte*)area)));
+#endif /* UNIV_DISABLE_MEM_POOL */
 }
 
 /************************************************************************
@@ -459,6 +463,9 @@ mem_area_free(
 				buffer */
 	mem_pool_t*	pool)	/* in: memory pool */
 {
+#ifdef UNIV_DISABLE_MEM_POOL
+        free(ptr);
+#else /* UNIV_DISABLE_MEM_POOL */
 	mem_area_t*	area;
 	mem_area_t*	buddy;
 	void*		new_ptr;
@@ -570,6 +577,7 @@ mem_area_free(
 	mutex_exit(&(pool->mutex));
 
 	ut_ad(mem_pool_validate(pool));
+#endif /* UNIV_DISABLE_MEM_POOL */
 }
 
 /************************************************************************

storage/innobase/row/row0sel.c

@@ -1248,7 +1248,7 @@ row_sel(
 			rw_lock_s_lock(&btr_search_latch);
 
 			search_latch_locked = TRUE;
-		} else if (btr_search_latch.writer_is_wait_ex) {
+		} else if (rw_lock_get_writer(&btr_search_latch) == RW_LOCK_WAIT_EX) {
 
 			/* There is an x-latch request waiting: release the
 			s-latch for a moment; as an s-latch here is often
@@ -3327,7 +3327,7 @@ row_search_for_mysql(
 	/* PHASE 0: Release a possible s-latch we are holding on the
 	adaptive hash index latch if there is someone waiting behind */
 
-	if (UNIV_UNLIKELY(btr_search_latch.writer != RW_LOCK_NOT_LOCKED)
+	if (UNIV_UNLIKELY(rw_lock_get_writer(&btr_search_latch) != RW_LOCK_NOT_LOCKED)
 	    && trx->has_search_latch) {
 
 		/* There is an x-latch request on the adaptive hash index:

storage/innobase/srv/srv0srv.c

@@ -1834,6 +1834,16 @@ srv_export_innodb_status(void)
 	export_vars.innodb_buffer_pool_pages_misc = buf_pool->max_size
 		- UT_LIST_GET_LEN(buf_pool->LRU)
 		- UT_LIST_GET_LEN(buf_pool->free);
+#ifdef HAVE_GCC_ATOMIC_BUILTINS
+	export_vars.innodb_have_atomic_builtins = 1;
+#else
+	export_vars.innodb_have_atomic_builtins = 0;
+#endif
+#ifdef UNIV_DISABLE_MEM_POOL
+	export_vars.innodb_heap_enabled = 0;
+#else
+	export_vars.innodb_heap_enabled = 1;
+#endif
 	export_vars.innodb_page_size = UNIV_PAGE_SIZE;
 	export_vars.innodb_log_waits = srv_log_waits;
 	export_vars.innodb_os_log_written = srv_os_log_written;

storage/innobase/srv/srv0start.c

@@ -1062,6 +1062,16 @@ innobase_start_or_create_for_mysql(void)
 		return(DB_ERROR);
 	}
 
+#ifdef UNIV_DISABLE_MEM_POOL
+	fprintf(stderr,
+		"InnoDB: The InnoDB memory heap has been disabled.\n");
+#endif
+
+#ifdef HAVE_GCC_ATOMIC_BUILTINS
+	fprintf(stderr,
+		"InnoDB: Mutex and rw_lock use GCC atomic builtins.\n");
+#endif
+
 	/* Since InnoDB does not currently clean up all its internal data
 	structures in MySQL Embedded Server Library server_end(), we
 	print an error message if someone tries to start up InnoDB a

storage/innobase/sync/sync0arr.c

@@ -295,28 +295,25 @@ sync_array_validate(
 }
 
 /***********************************************************************
-Puts the cell event in reset state. */
+Returns the event that the thread owning the cell waits for. */
 static
-ib_longlong
-sync_cell_event_reset(
-/*==================*/
-				/* out: value of signal_count
-				at the time of reset. */
-	ulint		type,	/* in: lock type mutex/rw_lock */
-	void*		object) /* in: the rw_lock/mutex object */
+os_event_t
+sync_cell_get_event(
+/*================*/
+	sync_cell_t*   	cell) /* in: non-empty sync array cell */
 {
+	ulint type = cell->request_type;
+
 	if (type == SYNC_MUTEX) {
-		return(os_event_reset(((mutex_t *) object)->event));
-#ifdef __WIN__
+		return(((mutex_t *) cell->wait_object)->event);
 	} else if (type == RW_LOCK_WAIT_EX) {
-		return(os_event_reset(
-		       ((rw_lock_t *) object)->wait_ex_event));
-#endif
-	} else {
-		return(os_event_reset(((rw_lock_t *) object)->event));
+		return(((rw_lock_t *) cell->wait_object)->wait_ex_event);
+	} else { /* RW_LOCK_SHARED and RW_LOCK_EX wait on the same event */
+		return(((rw_lock_t *) cell->wait_object)->event);
 	}
 }
 
+
 /**********************************************************************
 Reserves a wait array cell for waiting for an object.
 The event of the cell is reset to nonsignalled state. */
@@ -332,6 +329,7 @@ sync_array_reserve_cell(
 	ulint*		index)	/* out: index of the reserved cell */
 {
 	sync_cell_t*	cell;
+	os_event_t      event;
 	ulint		i;
 
 	ut_a(object);
@@ -370,8 +368,8 @@ sync_array_reserve_cell(
 			/* Make sure the event is reset and also store
 			the value of signal_count at which the event
 			was reset. */
-			cell->signal_count = sync_cell_event_reset(type,
-								object);
+                        event = sync_cell_get_event(cell);
+			cell->signal_count = os_event_reset(event);
 
 			cell->reservation_time = time(NULL);
 
@@ -411,19 +409,7 @@ sync_array_wait_event(
 	ut_a(!cell->waiting);
 	ut_ad(os_thread_get_curr_id() == cell->thread);
 
-	if (cell->request_type == SYNC_MUTEX) {
-		event = ((mutex_t*) cell->wait_object)->event;
-#ifdef __WIN__
-	/* On windows if the thread about to wait is the one which
-	has set the state of the rw_lock to RW_LOCK_WAIT_EX, then
-	it waits on a special event i.e.: wait_ex_event. */
-	} else if (cell->request_type == RW_LOCK_WAIT_EX) {
-		event = ((rw_lock_t*) cell->wait_object)->wait_ex_event;
-#endif
-	} else {
-		event = ((rw_lock_t*) cell->wait_object)->event;
-	}
-
+	event = sync_cell_get_event(cell);
 		cell->waiting = TRUE;
 
 #ifdef UNIV_SYNC_DEBUG
@@ -462,6 +448,7 @@ sync_array_cell_print(
 	mutex_t*	mutex;
 	rw_lock_t*	rwlock;
 	ulint		type;
+	ulint		writer;
 
 	type = cell->request_type;
 
@@ -491,9 +478,7 @@ sync_array_cell_print(
 			(ulong) mutex->waiters);
 
 	} else if (type == RW_LOCK_EX
-#ifdef __WIN__
 		   || type == RW_LOCK_WAIT_EX
-#endif
 		   || type == RW_LOCK_SHARED) {
 
 		fputs(type == RW_LOCK_EX ? "X-lock on" : "S-lock on", file);
@@ -504,22 +489,25 @@ sync_array_cell_print(
 			" RW-latch at %p created in file %s line %lu\n",
 			(void*) rwlock, rwlock->cfile_name,
 			(ulong) rwlock->cline);
-		if (rwlock->writer != RW_LOCK_NOT_LOCKED) {
+		writer = rw_lock_get_writer(rwlock);
+		if (writer != RW_LOCK_NOT_LOCKED) {
 			fprintf(file,
 				"a writer (thread id %lu) has"
 				" reserved it in mode %s",
 				(ulong) os_thread_pf(rwlock->writer_thread),
-				rwlock->writer == RW_LOCK_EX
+				writer == RW_LOCK_EX
 				? " exclusive\n"
 				: " wait exclusive\n");
 		}
 
 		fprintf(file,
-			"number of readers %lu, waiters flag %lu\n"
+			"number of readers %lu, waiters flag %lu, "
+                        "lock_word: %ld\n"
 			"Last time read locked in file %s line %lu\n"
 			"Last time write locked in file %s line %lu\n",
-			(ulong) rwlock->reader_count,
+			(ulong) rw_lock_get_reader_count(rwlock),
 			(ulong) rwlock->waiters,
+			rwlock->lock_word,
 			rwlock->last_s_file_name,
 			(ulong) rwlock->last_s_line,
 			rwlock->last_x_file_name,
@@ -778,28 +766,30 @@ sync_arr_cell_can_wake_up(
 			return(TRUE);
 		}
 
-	} else if (cell->request_type == RW_LOCK_EX
-		   || cell->request_type == RW_LOCK_WAIT_EX) {
+	} else if (cell->request_type == RW_LOCK_EX) {
 
 		lock = cell->wait_object;
 
-		if (rw_lock_get_reader_count(lock) == 0
-		    && rw_lock_get_writer(lock) == RW_LOCK_NOT_LOCKED) {
+                /* X_LOCK_DECR is the unlocked state */
+	    	if (lock->lock_word == X_LOCK_DECR) {
 
 			return(TRUE);
 		}
 
-		if (rw_lock_get_reader_count(lock) == 0
-		    && rw_lock_get_writer(lock) == RW_LOCK_WAIT_EX
-		    && os_thread_eq(lock->writer_thread, cell->thread)) {
+        } else if (cell->request_type == RW_LOCK_WAIT_EX) {
+
+	    	lock = cell->wait_object;
+
+                /* lock_word == 0 means all readers have left */
+	    	if (lock->lock_word == 0) {
 
 			return(TRUE);
 		}
-
 	} else if (cell->request_type == RW_LOCK_SHARED) {
 		lock = cell->wait_object;
 
-		if (rw_lock_get_writer(lock) == RW_LOCK_NOT_LOCKED) {
+                /* lock_word > 0 means no writer or reserved writer */
+		if (lock->lock_word > 0) {
 
 			return(TRUE);
 		}
@@ -844,11 +834,15 @@ sync_array_object_signalled(
 /*========================*/
 	sync_array_t*	arr)	/* in: wait array */
 {
+#ifdef HAVE_GCC_ATOMIC_BUILTINS
+	__sync_fetch_and_add(&(arr->sg_count),1);
+#else
 	sync_array_enter(arr);
 
 	arr->sg_count++;
 
 	sync_array_exit(arr);
+#endif
 }
 
 /**************************************************************************
@@ -868,6 +862,7 @@ sync_arr_wake_threads_if_sema_free(void)
 	sync_cell_t*	cell;
 	ulint		count;
 	ulint		i;
+	os_event_t      event;
 
 	sync_array_enter(arr);
 
@@ -877,36 +872,20 @@ sync_arr_wake_threads_if_sema_free(void)
 	while (count < arr->n_reserved) {
 
 		cell = sync_array_get_nth_cell(arr, i);
+		i++;
 
-		if (cell->wait_object != NULL) {
-
+		if (cell->wait_object == NULL) {
+			continue;
+		}
 			count++;
 
 			if (sync_arr_cell_can_wake_up(cell)) {
 
-				if (cell->request_type == SYNC_MUTEX) {
-					mutex_t*	mutex;
+			event = sync_cell_get_event(cell);
 
-					mutex = cell->wait_object;
-					os_event_set(mutex->event);
-#ifdef __WIN__
-				} else if (cell->request_type
-					   == RW_LOCK_WAIT_EX) {
-					rw_lock_t*	lock;
-
-					lock = cell->wait_object;
-					os_event_set(lock->wait_ex_event);
-#endif
-				} else {
-					rw_lock_t*	lock;
-
-					lock = cell->wait_object;
-					os_event_set(lock->event);
-				}
-			}
+			os_event_set(event);
 		}
 
-		i++;
 	}
 
 	sync_array_exit(arr);
@@ -1026,4 +1005,3 @@ sync_array_print_info(
 
 	sync_array_exit(arr);
 }
-

storage/innobase/sync/sync0sync.c

@@ -138,18 +138,13 @@ Therefore, this thread is guaranteed to catch the os_set_event()
 signalled unconditionally at the release of the lock.
 Q.E.D. */
 
-/* The number of system calls made in this module. Intended for performance
-monitoring. */
-
-ulint	mutex_system_call_count		= 0;
-
 /* Number of spin waits on mutexes: for performance monitoring */
 
 /* round=one iteration of a spin loop */
-ulint	mutex_spin_round_count		= 0;
-ulint	mutex_spin_wait_count		= 0;
-ulint	mutex_os_wait_count		= 0;
-ulint	mutex_exit_count		= 0;
+ib_longlong	mutex_spin_round_count		= 0;
+ib_longlong	mutex_spin_wait_count		= 0;
+ib_longlong	mutex_os_wait_count		= 0;
+ib_longlong	mutex_exit_count		= 0;
 
 /* The global array of wait cells for implementation of the database's own
 mutexes and read-write locks */
@@ -243,6 +238,8 @@ mutex_create_func(
 {
 #if defined(_WIN32) && defined(UNIV_CAN_USE_X86_ASSEMBLER)
 	mutex_reset_lock_word(mutex);
+#elif defined(HAVE_GCC_ATOMIC_BUILTINS)
+	mutex_reset_lock_word(mutex);
 #else
 	os_fast_mutex_init(&(mutex->os_fast_mutex));
 	mutex->lock_word = 0;
@@ -333,7 +330,9 @@ mutex_free(
 
 	os_event_free(mutex->event);
 
-#if !defined(_WIN32) || !defined(UNIV_CAN_USE_X86_ASSEMBLER)
+#if defined(_WIN32) && defined(UNIV_CAN_USE_X86_ASSEMBLER)
+#elif defined(HAVE_GCC_ATOMIC_BUILTINS)
+#else
 	os_fast_mutex_free(&(mutex->os_fast_mutex));
 #endif
 	/* If we free the mutex protecting the mutex list (freeing is
@@ -450,6 +449,12 @@ mutex_spin_wait(
 #endif /* UNIV_DEBUG && !UNIV_HOTBACKUP */
 	ut_ad(mutex);
 
+	/* This update is not thread safe, but we don't mind if the count
+	isn't exact. Moved out of ifdef that follows because we are willing
+	to sacrifice the cost of counting this as the data is valuable.
+	Count the number of calls to mutex_spin_wait. */
+	mutex_spin_wait_count++;
+
 mutex_loop:
 
 	i = 0;
@@ -462,7 +467,6 @@ mutex_spin_wait(
 
 spin_loop:
 #if defined UNIV_DEBUG && !defined UNIV_HOTBACKUP
-	mutex_spin_wait_count++;
 	mutex->count_spin_loop++;
 #endif /* UNIV_DEBUG && !UNIV_HOTBACKUP */
 
@@ -527,8 +531,6 @@ mutex_spin_wait(
 	sync_array_reserve_cell(sync_primary_wait_array, mutex,
 				SYNC_MUTEX, file_name, line, &index);
 
-	mutex_system_call_count++;
-
 	/* The memory order of the array reservation and the change in the
 	waiters field is important: when we suspend a thread, we first
 	reserve the cell and then set waiters field to 1. When threads are
@@ -575,7 +577,6 @@ mutex_spin_wait(
 		mutex->cfile_name, (ulong) mutex->cline, (ulong) i);
 #endif
 
-	mutex_system_call_count++;
 	mutex_os_wait_count++;
 
 #ifndef UNIV_HOTBACKUP
@@ -1377,21 +1378,31 @@ sync_print_wait_info(
 	FILE*	file)		/* in: file where to print */
 {
 #ifdef UNIV_SYNC_DEBUG
-	fprintf(file, "Mutex exits %lu, rws exits %lu, rwx exits %lu\n",
+	fprintf(file, "Mutex exits %llu, rws exits %llu, rwx exits %llu\n",
 		mutex_exit_count, rw_s_exit_count, rw_x_exit_count);
 #endif
 
 	fprintf(file,
-		"Mutex spin waits %lu, rounds %lu, OS waits %lu\n"
-		"RW-shared spins %lu, OS waits %lu;"
-		" RW-excl spins %lu, OS waits %lu\n",
-		(ulong) mutex_spin_wait_count,
-		(ulong) mutex_spin_round_count,
-		(ulong) mutex_os_wait_count,
-		(ulong) rw_s_spin_wait_count,
-		(ulong) rw_s_os_wait_count,
-		(ulong) rw_x_spin_wait_count,
-		(ulong) rw_x_os_wait_count);
+		"Mutex spin waits %llu, rounds %llu, OS waits %llu\n"
+		"RW-shared spins %llu, OS waits %llu;"
+		" RW-excl spins %llu, OS waits %llu\n",
+		mutex_spin_wait_count,
+		mutex_spin_round_count,
+		mutex_os_wait_count,
+		rw_s_spin_wait_count,
+		rw_s_os_wait_count,
+		rw_x_spin_wait_count,
+		rw_x_os_wait_count);
+
+	fprintf(file,
+		"Spin rounds per wait: %.2f mutex, %.2f RW-shared, "
+		"%.2f RW-excl\n",
+		(double) mutex_spin_round_count /
+		(mutex_spin_wait_count ? mutex_spin_wait_count : 1),
+		(double) rw_s_spin_round_count /
+		(rw_s_spin_wait_count ? rw_s_spin_wait_count : 1),
+		(double) rw_x_spin_round_count /
+		(rw_x_spin_wait_count ? rw_x_spin_wait_count : 1));
 }
 
 /***********************************************************************