/***************************************************************************** Copyright (c) 1995, 2011, Oracle and/or its affiliates. All Rights Reserved. Copyright (c) 2008, Google Inc. Portions of this file contain modifications contributed and copyrighted by Google, Inc. Those modifications are gratefully acknowledged and are described briefly in the InnoDB documentation. The contributions by Google are incorporated with their permission, and subject to the conditions contained in the file COPYING.Google. 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 Free Software Foundation; version 2 of the License. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA *****************************************************************************/ /**************************************************//** @file include/os0sync.h The interface to the operating system synchronization primitives. Created 9/6/1995 Heikki Tuuri *******************************************************/ #ifndef os0sync_h #define os0sync_h #include "univ.i" #include "ut0lst.h" #include "sync0types.h" #ifdef __WIN__ /** Native event (slow)*/ typedef HANDLE os_native_event_t; /** Native mutex */ typedef CRITICAL_SECTION fast_mutex_t; /** Native condition variable. */ typedef CONDITION_VARIABLE os_cond_t; #else /** Native mutex */ typedef pthread_mutex_t fast_mutex_t; /** Native condition variable */ typedef pthread_cond_t os_cond_t; #endif /** Structure that includes Performance Schema Probe pfs_psi in the os_fast_mutex structure if UNIV_PFS_MUTEX is defined */ struct os_fast_mutex_t { fast_mutex_t mutex; /*!< os_fast_mutex */ #ifdef UNIV_PFS_MUTEX struct PSI_mutex* pfs_psi;/*!< The performance schema instrumentation hook */ #endif }; /** Operating system event handle */ typedef struct os_event* os_event_t; /** An asynchronous signal sent between threads */ struct os_event { #ifdef __WIN__ HANDLE handle; /*!< kernel event object, slow, used on older Windows */ #endif os_fast_mutex_t os_mutex; /*!< this mutex protects the next fields */ ibool is_set; /*!< this is TRUE when the event is in the signaled state, i.e., a thread does not stop if it tries to wait for this event */ ib_int64_t signal_count; /*!< this is incremented each time the event becomes signaled */ os_cond_t cond_var; /*!< condition variable is used in waiting for the event */ UT_LIST_NODE_T(os_event_t) os_event_list; /*!< list of all created events */ }; /** Denotes an infinite delay for os_event_wait_time() */ #define OS_SYNC_INFINITE_TIME ULINT_UNDEFINED /** Return value of os_event_wait_time() when the time is exceeded */ #define OS_SYNC_TIME_EXCEEDED 1 /** Operating system mutex handle */ typedef struct os_mutex_t* os_ib_mutex_t; /** Mutex protecting counts and the event and OS 'slow' mutex lists */ extern os_ib_mutex_t os_sync_mutex; /** This is incremented by 1 in os_thread_create and decremented by 1 in os_thread_exit */ extern ulint os_thread_count; extern ulint os_event_count; extern ulint os_mutex_count; extern ulint os_fast_mutex_count; /*********************************************************//** Initializes global event and OS 'slow' mutex lists. */ UNIV_INTERN void os_sync_init(void); /*==============*/ /*********************************************************//** Frees created events and OS 'slow' mutexes. */ UNIV_INTERN void os_sync_free(void); /*==============*/ /*********************************************************//** 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); /*==================*/ /**********************************************************//** Sets an event semaphore to the signaled state: lets waiting threads proceed. */ UNIV_INTERN void os_event_set( /*=========*/ os_event_t event); /*!< in: event to set */ /**********************************************************//** Resets an event semaphore to the nonsignaled state. Waiting threads will stop to wait for the event. The return value should be passed to os_even_wait_low() if it is desired that this thread should not wait in case of an intervening call to os_event_set() between this os_event_reset() and the os_event_wait_low() call. See comments for os_event_wait_low(). */ UNIV_INTERN ib_int64_t os_event_reset( /*===========*/ os_event_t event); /*!< in: event to reset */ /**********************************************************//** Frees an event object. */ UNIV_INTERN void os_event_free( /*==========*/ os_event_t event); /*!< in: event to free */ /**********************************************************//** Waits for an event object until it is in the signaled state. Typically, if the event has been signalled after the os_event_reset() we'll return immediately because event->is_set == TRUE. There are, however, situations (e.g.: sync_array code) where we may lose this information. For example: thread A calls os_event_reset() thread B calls os_event_set() [event->is_set == TRUE] thread C calls os_event_reset() [event->is_set == FALSE] thread A calls os_event_wait() [infinite wait!] thread C calls os_event_wait() [infinite wait!] Where such a scenario is possible, to avoid infinite wait, the value returned by os_event_reset() should be passed in as reset_sig_count. */ UNIV_INTERN void os_event_wait_low( /*==============*/ os_event_t event, /*!< in: event to wait */ ib_int64_t reset_sig_count);/*!< in: zero or the value returned by previous call of os_event_reset(). */ #define os_event_wait(event) os_event_wait_low(event, 0) #define os_event_wait_time(event, t) os_event_wait_time_low(event, t, 0) /**********************************************************//** Waits for an event object until it is in the signaled state or a timeout is exceeded. @return 0 if success, OS_SYNC_TIME_EXCEEDED if timeout was exceeded */ UNIV_INTERN ulint os_event_wait_time_low( /*===================*/ os_event_t event, /*!< in: event to wait */ ulint time_in_usec, /*!< in: timeout in microseconds, or OS_SYNC_INFINITE_TIME */ ib_int64_t reset_sig_count); /*!< in: zero or the value returned by previous call of os_event_reset(). */ /*********************************************************//** Creates an operating system mutex semaphore. Because these are slow, the mutex semaphore of InnoDB itself (ib_mutex_t) should be used where possible. @return the mutex handle */ UNIV_INTERN os_ib_mutex_t os_mutex_create(void); /*=================*/ /**********************************************************//** Acquires ownership of a mutex semaphore. */ UNIV_INTERN void os_mutex_enter( /*===========*/ os_ib_mutex_t mutex); /*!< in: mutex to acquire */ /**********************************************************//** Releases ownership of a mutex. */ UNIV_INTERN void os_mutex_exit( /*==========*/ os_ib_mutex_t mutex); /*!< in: mutex to release */ /**********************************************************//** Frees an mutex object. */ UNIV_INTERN void os_mutex_free( /*==========*/ os_ib_mutex_t mutex); /*!< in: mutex to free */ /**********************************************************//** Acquires ownership of a fast mutex. Currently in Windows this is the same as os_fast_mutex_lock! @return 0 if success, != 0 if was reserved by another thread */ UNIV_INLINE ulint os_fast_mutex_trylock( /*==================*/ os_fast_mutex_t* fast_mutex); /*!< in: mutex to acquire */ /********************************************************************** Following os_fast_ mutex APIs would be performance schema instrumented: os_fast_mutex_init os_fast_mutex_lock os_fast_mutex_unlock os_fast_mutex_free These mutex APIs will point to corresponding wrapper functions that contain the performance schema instrumentation. NOTE! The following macro should be used in mutex operation, not the corresponding function. */ #ifdef UNIV_PFS_MUTEX # define os_fast_mutex_init(K, M) \ pfs_os_fast_mutex_init(K, M) # define os_fast_mutex_lock(M) \ pfs_os_fast_mutex_lock(M, __FILE__, __LINE__) # define os_fast_mutex_unlock(M) pfs_os_fast_mutex_unlock(M) # define os_fast_mutex_free(M) pfs_os_fast_mutex_free(M) /*********************************************************//** NOTE! Please use the corresponding macro os_fast_mutex_init(), not directly this function! A wrapper function for os_fast_mutex_init_func(). Initializes an operating system fast mutex semaphore. */ UNIV_INLINE void pfs_os_fast_mutex_init( /*===================*/ PSI_mutex_key key, /*!< in: Performance Schema key */ os_fast_mutex_t* fast_mutex); /*!< out: fast mutex */ /**********************************************************//** NOTE! Please use the corresponding macro os_fast_mutex_free(), not directly this function! Wrapper function for pfs_os_fast_mutex_free(). Also destroys the performance schema probes when freeing the mutex */ UNIV_INLINE void pfs_os_fast_mutex_free( /*===================*/ os_fast_mutex_t* fast_mutex); /*!< in/out: mutex to free */ /**********************************************************//** NOTE! Please use the corresponding macro os_fast_mutex_lock, not directly this function! Wrapper function of os_fast_mutex_lock. Acquires ownership of a fast mutex. */ UNIV_INLINE void pfs_os_fast_mutex_lock( /*===================*/ os_fast_mutex_t* fast_mutex, /*!< in/out: mutex to acquire */ const char* file_name, /*!< in: file name where locked */ ulint line); /*!< in: line where locked */ /**********************************************************//** NOTE! Please use the corresponding macro os_fast_mutex_unlock, not directly this function! Wrapper function of os_fast_mutex_unlock. Releases ownership of a fast mutex. */ UNIV_INLINE void pfs_os_fast_mutex_unlock( /*=====================*/ os_fast_mutex_t* fast_mutex); /*!< in/out: mutex to release */ #else /* UNIV_PFS_MUTEX */ # define os_fast_mutex_init(K, M) \ os_fast_mutex_init_func(&((os_fast_mutex_t*)(M))->mutex) # define os_fast_mutex_lock(M) \ os_fast_mutex_lock_func(&((os_fast_mutex_t*)(M))->mutex) # define os_fast_mutex_unlock(M) \ os_fast_mutex_unlock_func(&((os_fast_mutex_t*)(M))->mutex) # define os_fast_mutex_free(M) \ os_fast_mutex_free_func(&((os_fast_mutex_t*)(M))->mutex) #endif /* UNIV_PFS_MUTEX */ /**********************************************************//** Releases ownership of a fast mutex. */ UNIV_INTERN void os_fast_mutex_unlock_func( /*======================*/ fast_mutex_t* fast_mutex); /*!< in: mutex to release */ /*********************************************************//** Initializes an operating system fast mutex semaphore. */ UNIV_INTERN void os_fast_mutex_init_func( /*====================*/ fast_mutex_t* fast_mutex); /*!< in: fast mutex */ /**********************************************************//** Acquires ownership of a fast mutex. */ UNIV_INTERN void os_fast_mutex_lock_func( /*====================*/ fast_mutex_t* fast_mutex); /*!< in: mutex to acquire */ /**********************************************************//** Frees an mutex object. */ UNIV_INTERN void os_fast_mutex_free_func( /*====================*/ fast_mutex_t* fast_mutex); /*!< in: mutex to free */ /**********************************************************//** Atomic compare-and-swap and increment for InnoDB. */ #if defined(HAVE_IB_GCC_ATOMIC_BUILTINS) # define HAVE_ATOMIC_BUILTINS # ifdef HAVE_IB_GCC_ATOMIC_BUILTINS_64 # define HAVE_ATOMIC_BUILTINS_64 # endif /**********************************************************//** Returns true if swapped, ptr is pointer to target, old_val is value to compare to, new_val is the value to swap in. */ # define os_compare_and_swap(ptr, old_val, new_val) \ __sync_bool_compare_and_swap(ptr, old_val, new_val) # define os_compare_and_swap_ulint(ptr, old_val, new_val) \ os_compare_and_swap(ptr, old_val, new_val) # define os_compare_and_swap_lint(ptr, old_val, new_val) \ os_compare_and_swap(ptr, old_val, new_val) # ifdef HAVE_IB_ATOMIC_PTHREAD_T_GCC # define os_compare_and_swap_thread_id(ptr, old_val, new_val) \ os_compare_and_swap(ptr, old_val, new_val) # define INNODB_RW_LOCKS_USE_ATOMICS # define IB_ATOMICS_STARTUP_MSG \ "Mutexes and rw_locks use GCC atomic builtins" # else /* HAVE_IB_ATOMIC_PTHREAD_T_GCC */ # define IB_ATOMICS_STARTUP_MSG \ "Mutexes use GCC atomic builtins, rw_locks do not" # endif /* HAVE_IB_ATOMIC_PTHREAD_T_GCC */ /**********************************************************//** Returns the resulting value, ptr is pointer to target, amount is the amount of increment. */ # define os_atomic_increment(ptr, amount) \ __sync_add_and_fetch(ptr, amount) # define os_atomic_increment_lint(ptr, amount) \ os_atomic_increment(ptr, amount) # define os_atomic_increment_ulint(ptr, amount) \ os_atomic_increment(ptr, amount) # define os_atomic_increment_uint64(ptr, amount) \ os_atomic_increment(ptr, amount) /* Returns the resulting value, ptr is pointer to target, amount is the amount to decrement. */ # define os_atomic_decrement(ptr, amount) \ __sync_sub_and_fetch(ptr, amount) # define os_atomic_decrement_lint(ptr, amount) \ os_atomic_decrement(ptr, amount) # define os_atomic_decrement_ulint(ptr, amount) \ os_atomic_decrement(ptr, amount) # define os_atomic_decrement_uint64(ptr, amount) \ os_atomic_decrement(ptr, amount) /**********************************************************//** Returns the old value of *ptr, atomically sets *ptr to new_val */ # define os_atomic_test_and_set_byte(ptr, new_val) \ __sync_lock_test_and_set(ptr, (byte) new_val) # define os_atomic_test_and_set_ulint(ptr, new_val) \ __sync_lock_test_and_set(ptr, new_val) #elif defined(HAVE_IB_SOLARIS_ATOMICS) # define HAVE_ATOMIC_BUILTINS # define HAVE_ATOMIC_BUILTINS_64 /* If not compiling with GCC or GCC doesn't support the atomic intrinsics and running on Solaris >= 10 use Solaris atomics */ # include /**********************************************************//** Returns true if swapped, ptr is pointer to target, old_val is value to compare to, new_val is the value to swap in. */ # define os_compare_and_swap_ulint(ptr, old_val, new_val) \ (atomic_cas_ulong(ptr, old_val, new_val) == old_val) # define os_compare_and_swap_lint(ptr, old_val, new_val) \ ((lint) atomic_cas_ulong((ulong_t*) ptr, old_val, new_val) == old_val) # ifdef HAVE_IB_ATOMIC_PTHREAD_T_SOLARIS # if SIZEOF_PTHREAD_T == 4 # define os_compare_and_swap_thread_id(ptr, old_val, new_val) \ ((pthread_t) atomic_cas_32(ptr, old_val, new_val) == old_val) # elif SIZEOF_PTHREAD_T == 8 # define os_compare_and_swap_thread_id(ptr, old_val, new_val) \ ((pthread_t) atomic_cas_64(ptr, old_val, new_val) == old_val) # else # error "SIZEOF_PTHREAD_T != 4 or 8" # endif /* SIZEOF_PTHREAD_T CHECK */ # define INNODB_RW_LOCKS_USE_ATOMICS # define IB_ATOMICS_STARTUP_MSG \ "Mutexes and rw_locks use Solaris atomic functions" # else /* HAVE_IB_ATOMIC_PTHREAD_T_SOLARIS */ # define IB_ATOMICS_STARTUP_MSG \ "Mutexes use Solaris atomic functions, rw_locks do not" # endif /* HAVE_IB_ATOMIC_PTHREAD_T_SOLARIS */ /**********************************************************//** Returns the resulting value, ptr is pointer to target, amount is the amount of increment. */ # define os_atomic_increment_ulint(ptr, amount) \ atomic_add_long_nv(ptr, amount) # define os_atomic_increment_lint(ptr, amount) \ os_atomic_increment_ulint((ulong_t*) ptr, amount) # define os_atomic_increment_uint64(ptr, amount) \ atomic_add_64_nv(ptr, amount) /* Returns the resulting value, ptr is pointer to target, amount is the amount to decrement. */ # define os_atomic_decrement_lint(ptr, amount) \ os_atomic_increment_ulint((ulong_t*) ptr, -(amount)) # define os_atomic_decrement_ulint(ptr, amount) \ os_atomic_increment_ulint(ptr, -(amount)) # define os_atomic_decrement_uint64(ptr, amount) \ os_atomic_increment_uint64(ptr, -(amount)) /**********************************************************//** Returns the old value of *ptr, atomically sets *ptr to new_val */ # define os_atomic_test_and_set_byte(ptr, new_val) \ atomic_swap_uchar(ptr, new_val) # define os_atomic_test_and_set_ulint(ptr, new_val) \ atomic_swap_ulong(ptr, new_val) #elif defined(HAVE_WINDOWS_ATOMICS) # define HAVE_ATOMIC_BUILTINS # ifndef _WIN32 # define HAVE_ATOMIC_BUILTINS_64 # endif /**********************************************************//** Atomic compare and exchange of signed integers (both 32 and 64 bit). @return value found before the exchange. If it is not equal to old_value the exchange did not happen. */ UNIV_INLINE lint win_cmp_and_xchg_lint( /*==================*/ volatile lint* ptr, /*!< in/out: source/destination */ lint new_val, /*!< in: exchange value */ lint old_val); /*!< in: value to compare to */ /**********************************************************//** Atomic addition of signed integers. @return Initial value of the variable pointed to by ptr */ UNIV_INLINE lint win_xchg_and_add( /*=============*/ volatile lint* ptr, /*!< in/out: address of destination */ lint val); /*!< in: number to be added */ /**********************************************************//** Atomic compare and exchange of unsigned integers. @return value found before the exchange. If it is not equal to old_value the exchange did not happen. */ UNIV_INLINE ulint win_cmp_and_xchg_ulint( /*===================*/ volatile ulint* ptr, /*!< in/out: source/destination */ ulint new_val, /*!< in: exchange value */ ulint old_val); /*!< in: value to compare to */ /**********************************************************//** Atomic compare and exchange of 32 bit unsigned integers. @return value found before the exchange. If it is not equal to old_value the exchange did not happen. */ UNIV_INLINE DWORD win_cmp_and_xchg_dword( /*===================*/ volatile DWORD* ptr, /*!< in/out: source/destination */ DWORD new_val, /*!< in: exchange value */ DWORD old_val); /*!< in: value to compare to */ /**********************************************************//** Returns true if swapped, ptr is pointer to target, old_val is value to compare to, new_val is the value to swap in. */ # define os_compare_and_swap_ulint(ptr, old_val, new_val) \ (win_cmp_and_xchg_ulint(ptr, new_val, old_val) == old_val) # define os_compare_and_swap_lint(ptr, old_val, new_val) \ (win_cmp_and_xchg_lint(ptr, new_val, old_val) == old_val) /* windows thread objects can always be passed to windows atomic functions */ # define os_compare_and_swap_thread_id(ptr, old_val, new_val) \ (win_cmp_and_xchg_dword(ptr, new_val, old_val) == old_val) # define INNODB_RW_LOCKS_USE_ATOMICS # define IB_ATOMICS_STARTUP_MSG \ "Mutexes and rw_locks use Windows interlocked functions" /**********************************************************//** Returns the resulting value, ptr is pointer to target, amount is the amount of increment. */ # define os_atomic_increment_lint(ptr, amount) \ (win_xchg_and_add(ptr, amount) + amount) # define os_atomic_increment_ulint(ptr, amount) \ ((ulint) (win_xchg_and_add((lint*) ptr, (lint) amount) + amount)) # define os_atomic_increment_uint64(ptr, amount) \ ((ib_uint64_t) (InterlockedExchangeAdd64( \ (ib_int64_t*) ptr, \ (ib_int64_t) amount) + amount)) /**********************************************************//** Returns the resulting value, ptr is pointer to target, amount is the amount to decrement. There is no atomic substract function on Windows */ # define os_atomic_decrement_lint(ptr, amount) \ (win_xchg_and_add(ptr, -(lint) amount) - amount) # define os_atomic_decrement_ulint(ptr, amount) \ ((ulint) (win_xchg_and_add((lint*) ptr, -(lint) amount) - amount)) # define os_atomic_decrement_uint64(ptr, amount) \ ((ib_uint64_t) (InterlockedExchangeAdd64( \ (ib_int64_t*) ptr, \ -(ib_int64_t) amount) - amount)) /**********************************************************//** Returns the old value of *ptr, atomically sets *ptr to new_val. InterlockedExchange() operates on LONG, and the LONG will be clobbered */ # define os_atomic_test_and_set_byte(ptr, new_val) \ ((byte) InterlockedExchange(ptr, new_val)) # define os_atomic_test_and_set_ulong(ptr, new_val) \ InterlockedExchange(ptr, new_val) #else # define IB_ATOMICS_STARTUP_MSG \ "Mutexes and rw_locks use InnoDB's own implementation" #endif #ifdef HAVE_ATOMIC_BUILTINS #define os_atomic_inc_ulint(m,v,d) os_atomic_increment_ulint(v, d) #define os_atomic_dec_ulint(m,v,d) os_atomic_decrement_ulint(v, d) #else #define os_atomic_inc_ulint(m,v,d) os_atomic_inc_ulint_func(m, v, d) #define os_atomic_dec_ulint(m,v,d) os_atomic_dec_ulint_func(m, v, d) #endif /* HAVE_ATOMIC_BUILTINS */ /**********************************************************//** Following macros are used to update specified counter atomically if HAVE_ATOMIC_BUILTINS defined. Otherwise, use mutex passed in for synchronization */ #ifdef HAVE_ATOMIC_BUILTINS #define os_increment_counter_by_amount(mutex, counter, amount) \ (void) os_atomic_increment_ulint(&counter, amount) #define os_decrement_counter_by_amount(mutex, counter, amount) \ (void) os_atomic_increment_ulint(&counter, (-((lint) amount))) #else #define os_increment_counter_by_amount(mutex, counter, amount) \ do { \ mutex_enter(&(mutex)); \ (counter) += (amount); \ mutex_exit(&(mutex)); \ } while (0) #define os_decrement_counter_by_amount(mutex, counter, amount) \ do { \ ut_a(counter >= amount); \ mutex_enter(&(mutex)); \ (counter) -= (amount); \ mutex_exit(&(mutex)); \ } while (0) #endif /* HAVE_ATOMIC_BUILTINS */ #define os_inc_counter(mutex, counter) \ os_increment_counter_by_amount(mutex, counter, 1) #define os_dec_counter(mutex, counter) \ do { \ os_decrement_counter_by_amount(mutex, counter, 1);\ } while (0); #ifndef UNIV_NONINL #include "os0sync.ic" #endif #endif