ethread.h

OTP是开放电信平台的简称

/* ``The contents of this file are subject to the Erlang Public License,
 * Version 1.1, (the "License"); you may not use this file except in
 * compliance with the License. You should have received a copy of the
 * Erlang Public License along with this software. If not, it can be
 * retrieved via the world wide web at http://www.erlang.org/.
 * 
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 * 
 * The Initial Developer of the Original Code is Ericsson Utvecklings AB.
 * Portions created by Ericsson are Copyright 1999, Ericsson Utvecklings
 * AB. All Rights Reserved.''
 * 
 *     $Id$
 */

/*
 * Description: Thread library for use in the ERTS and other OTP
 *              applications.
 * Author: Rickard Green
 */

#ifndef ETHREAD_H__
#define ETHREAD_H__

#ifndef ETHR_HAVE_ETHREAD_DEFINES
#  include "ethread_header_config.h"
#endif

#include <stdlib.h>
#include <errno.h>

typedef struct {
    long tv_sec;
    long tv_nsec;
} ethr_timeval;

#if defined(DEBUG)
#  undef ETHR_XCHK
#  define  ETHR_XCHK 1
#else
#  ifndef ETHR_XCHK
#    define ETHR_XCHK 0
#  endif
#endif

#undef ETHR_INLINE
#if defined(__GNUC__)
#  define ETHR_INLINE __inline__
#elif defined(__WIN32__)
#  define ETHR_INLINE __forceinline
#endif
#if defined(DEBUG) || !defined(ETHR_INLINE) || ETHR_XCHK
#  undef ETHR_TRY_INLINE_FUNCS
#endif

#define ETHR_RWMUTEX_INITIALIZED 	0x99999999
#define ETHR_MUTEX_INITIALIZED		0x77777777
#define ETHR_COND_INITIALIZED		0x55555555

#if defined(ETHR_PTHREADS)
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\
 * The pthread implementation                                                *
\*                                                                           */

#if defined(__linux__) && !defined(_GNU_SOURCE)
#error "_GNU_SOURCE not defined. Please, compile all files with -D_GNU_SOURCE."
#endif

#if defined(ETHR_HAVE_MIT_PTHREAD_H)
#include <pthread/mit/pthread.h>
#elif defined(ETHR_HAVE_PTHREAD_H)
#include <pthread.h>
#endif

#define ETHR_HAVE_ETHR_MUTEX_TRYLOCK 1

/* Types */

typedef pthread_t ethr_tid;

typedef struct ethr_mutex_ ethr_mutex;
struct ethr_mutex_ {
    pthread_mutex_t pt_mtx;
    int is_rec_mtx;
    ethr_mutex *prev;
    ethr_mutex *next;
#if ETHR_XCHK
    int initialized;
#endif
};

typedef struct ethr_cond_ ethr_cond;
struct ethr_cond_ {
    pthread_cond_t pt_cnd;
#if ETHR_XCHK
    int initialized;
#endif
};

#ifdef ETHR_EXTENDED_LIB

typedef struct ethr_rwmutex_ ethr_rwmutex;
struct ethr_rwmutex_ {
    pthread_rwlock_t pt_rwlock;
#if ETHR_XCHK
    int initialized;
#endif
};

#endif

/* Static initializers */
#if ETHR_XCHK
#define ETHR_MUTEX_XCHK_INITER	, ETHR_MUTEX_INITIALIZED
#define ETHR_COND_XCHK_INITER	, ETHR_COND_INITIALIZED
#else
#define ETHR_MUTEX_XCHK_INITER
#define ETHR_COND_XCHK_INITER
#endif

#define ETHR_MUTEX_INITER {PTHREAD_MUTEX_INITIALIZER, 0, NULL, NULL ETHR_MUTEX_XCHK_INITER}
#define ETHR_COND_INITER {PTHREAD_COND_INITIALIZER ETHR_COND_XCHK_INITER}

#if defined(ETHR_HAVE_PTHREAD_MUTEXATTR_SETTYPE) \
    || defined(ETHR_HAVE_PTHREAD_MUTEXATTR_SETKIND_NP)
#  define ETHR_HAVE_ETHR_REC_MUTEX_INIT 1
#  ifdef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
#    define ETHR_REC_MUTEX_INITER \
            {PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP, 1, NULL, NULL ETHR_MUTEX_XCHK_INITER}
#  endif
#else
#  undef ETHR_HAVE_ETHR_REC_MUTEX_INIT
#endif

#ifndef ETHR_HAVE_PTHREAD_ATFORK
#  define ETHR_NO_FORKSAFETY 1
#endif

typedef pthread_key_t ethr_tsd_key;

#define ETHR_HAVE_ETHR_SIG_FUNCS 1

#ifdef ETHR_EXTENDED_LIB

#if (!defined(__builtin_expect) \
     || !defined(__GNUC__) \
     || (__GNUC__ < 3 && __GNUC_MINOR__ < 96))
#define __builtin_expect(X, Y) (X)
#endif

/* For CPU-optimised atomics, spinlocks, and rwlocks. */
#if defined(__GNUC__)
#if defined(__i386__)
#include "i386/ethread.h"
#elif defined(__x86_64__)
#include "x86_64/ethread.h"
#elif (defined(__powerpc__) || defined(__ppc__)) && !defined(__powerpc64__)
#include "ppc32/ethread.h"
#elif defined(__sparc__)
#include "sparc32/ethread.h"
#endif
#endif /* __GNUC__ */

#if defined(PURIFY) || defined(VALGRIND) || defined(ETHR_DISABLE_NATIVE_OPS)
#undef ETHR_HAVE_NATIVE_ATOMICS
#undef ETHR_HAVE_NATIVE_LOCKS
#endif

#ifdef ETHR_HAVE_NATIVE_ATOMICS
/*
 * Map ethread native atomics to ethread API atomics.
 */
typedef ethr_native_atomic_t ethr_atomic_t;

static ETHR_INLINE int
ethr_atomic_init(ethr_atomic_t *var, long i)
{
    ethr_native_atomic_init(var, i);
    return 0;
}

static ETHR_INLINE int
ethr_atomic_set(ethr_atomic_t *var, long i)
{
    ethr_native_atomic_set(var, i);
    return 0;
}

static ETHR_INLINE int
ethr_atomic_read(ethr_atomic_t *var, long *i)
{
    *i = ethr_native_atomic_read(var);
    return 0;
}

static ETHR_INLINE int
ethr_atomic_add(ethr_atomic_t *var, long incr)
{
    ethr_native_atomic_add(var, incr);
    return 0;
}   
    
static ETHR_INLINE int
ethr_atomic_addtest(ethr_atomic_t *var, long i, long *testp)
{
    *testp = ethr_native_atomic_add_return(var, i);
    return 0;
}

static ETHR_INLINE int
ethr_atomic_inc(ethr_atomic_t *var)
{
    ethr_native_atomic_inc(var);
    return 0;
}

static ETHR_INLINE int
ethr_atomic_dec(ethr_atomic_t *var)
{
    ethr_native_atomic_dec(var);
    return 0;
}

static ETHR_INLINE int
ethr_atomic_inctest(ethr_atomic_t *var, long *testp)
{
    *testp = ethr_native_atomic_inc_return(var);
    return 0;
}

static ETHR_INLINE int
ethr_atomic_dectest(ethr_atomic_t *var, long *testp)
{
    *testp = ethr_native_atomic_dec_return(var);
    return 0;
}

static ETHR_INLINE int
ethr_atomic_and_old(ethr_atomic_t *var, long mask, long *old)
{
    *old = ethr_native_atomic_and_retold(var, mask);
    return 0;
}

static ETHR_INLINE int
ethr_atomic_or_old(ethr_atomic_t *var, long mask, long *old)
{
    *old = ethr_native_atomic_or_retold(var, mask);
    return 0;
}

static ETHR_INLINE int
ethr_atomic_xchg(ethr_atomic_t *var, long new, long *old)
{
    *old = ethr_native_atomic_xchg(var, new);
    return 0;
}   

#define ETHR_HAVE_OPTIMIZED_ATOMIC_OPS 1
#endif /* ETHR_HAVE_NATIVE_ATOMICS */

#ifdef ETHR_HAVE_NATIVE_LOCKS
/*
 * Map ethread native spinlocks to ethread API spinlocks.
 */
typedef ethr_native_spinlock_t ethr_spinlock_t;

static ETHR_INLINE int
ethr_spinlock_init(ethr_spinlock_t *lock)
{
    ethr_native_spinlock_init(lock);
    return 0;
}

static ETHR_INLINE int
ethr_spinlock_destroy(ethr_spinlock_t *lock)
{
    return 0;
}

static ETHR_INLINE int
ethr_spin_unlock(ethr_spinlock_t *lock)
{
    ethr_native_spin_unlock(lock);
    return 0;
}

static ETHR_INLINE int
ethr_spin_lock(ethr_spinlock_t *lock)
{
    ethr_native_spin_lock(lock);
    return 0;
}

/*
 * Map ethread native rwlocks to ethread API rwlocks.
 */
typedef ethr_native_rwlock_t ethr_rwlock_t;

static ETHR_INLINE int
ethr_rwlock_init(ethr_rwlock_t *lock)
{
    ethr_native_rwlock_init(lock);
    return 0;
}

static ETHR_INLINE int
ethr_rwlock_destroy(ethr_rwlock_t *lock)
{
    return 0;
}

static ETHR_INLINE int
ethr_read_unlock(ethr_rwlock_t *lock)
{
    ethr_native_read_unlock(lock);
    return 0;
}

static ETHR_INLINE int
ethr_read_lock(ethr_rwlock_t *lock)
{
    ethr_native_read_lock(lock);
    return 0;
}

static ETHR_INLINE int
ethr_write_unlock(ethr_rwlock_t *lock)
{
    ethr_native_write_unlock(lock);
    return 0;
}

static ETHR_INLINE int
ethr_write_lock(ethr_rwlock_t *lock)
{
    ethr_native_write_lock(lock);
    return 0;
}

#define ETHR_HAVE_OPTIMIZED_LOCKS 1
#endif /* ETHR_HAVE_NATIVE_LOCKS */

#endif /* #ifdef ETHR_EXTENDED_LIB */

#ifndef ETHR_HAVE_OPTIMIZED_ATOMIC_OPS

#define ETHR_ATOMIC_ADDR_BITS 4
#define ETHR_ATOMIC_ADDR_SHIFT 3

#ifdef ETHR_HAVE_PTHREAD_SPIN_LOCK

extern pthread_spinlock_t ethr_atomic_spinlock[1 << ETHR_ATOMIC_ADDR_BITS];

#define ETHR_ATOMIC_PTR2LCK__(PTR) \
(&ethr_atomic_spinlock[((((unsigned long) (PTR)) >> ETHR_ATOMIC_ADDR_SHIFT) \
			& ((1 << ETHR_ATOMIC_ADDR_BITS) - 1))])


#define ETHR_ATOMIC_OP_FALLBACK_IMPL__(AP, EXPS)			\
do {									\
    pthread_spinlock_t *slp__ = ETHR_ATOMIC_PTR2LCK__((AP));		\
    int res__ = pthread_spin_lock(slp__);				\
    if (res__ != 0)							\
	return res__;							\
    { EXPS; }								\
    return pthread_spin_unlock(slp__);					\
} while (0)

#else

extern pthread_mutex_t ethr_atomic_mutex[1 << ETHR_ATOMIC_ADDR_BITS];

#define ETHR_ATOMIC_PTR2LCK__(PTR) \
(&ethr_atomic_mutex[((((unsigned long) (PTR)) >> ETHR_ATOMIC_ADDR_SHIFT) \
		     & ((1 << ETHR_ATOMIC_ADDR_BITS) - 1))])

#define ETHR_ATOMIC_OP_FALLBACK_IMPL__(AP, EXPS)			\
do {									\
    pthread_mutex_t *mtxp__ = ETHR_ATOMIC_PTR2LCK__((AP));		\
    int res__ = pthread_mutex_lock(mtxp__);				\
    if (res__ != 0)							\
	return res__;							\
    { EXPS; }								\
    return pthread_mutex_unlock(mtxp__);				\
} while (0)

#endif

typedef long ethr_atomic_t;

#endif

#ifndef ETHR_HAVE_OPTIMIZED_LOCKS

#ifdef ETHR_HAVE_PTHREAD_SPIN_LOCK
typedef struct {
    pthread_spinlock_t spnlck;
} ethr_spinlock_t;
typedef struct {
    pthread_spinlock_t spnlck;
    unsigned counter;
} ethr_rwlock_t;
#define ETHR_RWLOCK_WRITERS (((unsigned) 1) << 31)

#else

typedef struct {
    pthread_mutex_t mtx;
} ethr_spinlock_t;

typedef struct {
    pthread_rwlock_t rwlck;
} ethr_rwlock_t;

#endif

#endif

#ifdef ETHR_TRY_INLINE_FUNCS

static ETHR_INLINE int
ethr_mutex_trylock(ethr_mutex *mtx)
{
    return pthread_mutex_trylock(&mtx->pt_mtx);
}

static ETHR_INLINE int
ethr_mutex_lock(ethr_mutex *mtx)
{
    return pthread_mutex_lock(&mtx->pt_mtx);
}

static ETHR_INLINE int
ethr_mutex_unlock(ethr_mutex *mtx)
{
    return pthread_mutex_unlock(&mtx->pt_mtx);
}

#ifdef ETHR_EXTENDED_LIB

static ETHR_INLINE int
ethr_rwmutex_tryrlock(ethr_rwmutex *rwmtx)
{
    return pthread_rwlock_tryrdlock(&rwmtx->pt_rwlock);
}

static ETHR_INLINE int
ethr_rwmutex_rlock(ethr_rwmutex *rwmtx)
{
    return pthread_rwlock_rdlock(&rwmtx->pt_rwlock);
}

static ETHR_INLINE int
ethr_rwmutex_runlock(ethr_rwmutex *rwmtx)
{
    return pthread_rwlock_unlock(&rwmtx->pt_rwlock);
}

static ETHR_INLINE int
ethr_rwmutex_tryrwlock(ethr_rwmutex *rwmtx)
{
    return pthread_rwlock_trywrlock(&rwmtx->pt_rwlock);
}

static ETHR_INLINE int
ethr_rwmutex_rwlock(ethr_rwmutex *rwmtx)
{
    return pthread_rwlock_wrlock(&rwmtx->pt_rwlock);
}

static ETHR_INLINE int
ethr_rwmutex_rwunlock(ethr_rwmutex *rwmtx)
{
    return pthread_rwlock_unlock(&rwmtx->pt_rwlock);
}

#endif