kmp_lock.h

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/*
 * kmp_lock.h -- lock header file
 * $Revision: 42181 $
 * $Date: 2013-03-26 15:04:45 -0500 (Tue, 26 Mar 2013) $
 */

/* <copyright>
    Copyright (c) 1997-2013 Intel Corporation.  All Rights Reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions
    are met:

      * Redistributions of source code must retain the above copyright
        notice, this list of conditions and the following disclaimer.
      * Redistributions in binary form must reproduce the above copyright
        notice, this list of conditions and the following disclaimer in the
        documentation and/or other materials provided with the distribution.
      * Neither the name of Intel Corporation nor the names of its
        contributors may be used to endorse or promote products derived
        from this software without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
    HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.


------------------------------------------------------------------------

    Portions of this software are protected under the following patents:
        U.S. Patent 5,812,852
        U.S. Patent 6,792,599
        U.S. Patent 7,069,556
        U.S. Patent 7,328,433
        U.S. Patent 7,500,242

</copyright> */

#ifndef KMP_LOCK_H
#define KMP_LOCK_H

#include <limits.h>    // CHAR_BIT
#include <stddef.h>    // offsetof

#include "kmp_os.h"
#include "kmp_debug.h"

#ifdef __cplusplus
extern "C" {
#endif // __cplusplus

// ----------------------------------------------------------------------------
// Have to copy these definitions from kmp.h because kmp.h cannot be included
// due to circular dependencies.  Will undef these at end of file.

#define KMP_PAD(type, sz)     (sizeof(type) + (sz - ((sizeof(type) - 1) % (sz)) - 1))
#define KMP_GTID_DNE (-2)

// Forward declaration of ident and ident_t

struct ident;
typedef struct ident ident_t;

// End of copied code.
// ----------------------------------------------------------------------------

//
// We need to know the size of the area we can assume that the compiler(s)
// allocated for obects of type omp_lock_t and omp_nest_lock_t.  The Intel
// compiler always allocates a pointer-sized area, as does visual studio.
//
// gcc however, only allocates 4 bytes for regular locks, even on 64-bit
// intel archs.  It allocates at least 8 bytes for nested lock (more on
// recent versions), but we are bounded by the pointer-sized chunks that
// the Intel compiler allocates.
//

#if KMP_OS_LINUX && defined(KMP_GOMP_COMPAT)
# define OMP_LOCK_T_SIZE        sizeof(int)
# define OMP_NEST_LOCK_T_SIZE   sizeof(void *)
#else
# define OMP_LOCK_T_SIZE        sizeof(void *)
# define OMP_NEST_LOCK_T_SIZE   sizeof(void *)
#endif

//
// The Intel compiler allocates a 32-byte chunk for a critical section.
// Both gcc and visual studio only allocate enough space for a pointer.
// Sometimes we know that the space was allocated by the Intel compiler.
//
#define OMP_CRITICAL_SIZE       sizeof(void *)
#define INTEL_CRITICAL_SIZE     32

//
// lock flags
//
typedef kmp_uint32 kmp_lock_flags_t;

#define kmp_lf_critical_section 1
#define kmp_lf_atomic           2

//
// When a lock table is used, the indices are of kmp_lock_index_t
//
typedef kmp_uint32 kmp_lock_index_t;

//
// When memory allocated for locks are on the lock pool (free list),
// it is treated as structs of this type.
//
struct kmp_lock_pool {
    union kmp_user_lock *next;
    kmp_lock_index_t index;
};

typedef struct kmp_lock_pool kmp_lock_pool_t;


extern void __kmp_validate_locks( void );


// ----------------------------------------------------------------------------
//
//  There are 5 lock implementations:
//
//       1. Test and set locks.
//       2. futex locks (Linux* OS on x86 and Intel(R) Many Integrated Core architecture)
//       3. Ticket (Lamport bakery) locks.
//       4. Queuing locks (with separate spin fields).
//       5. DRPA (Dynamically Reconfigurable Distributed Polling Area) locks
//
//   and 3 lock purposes:
//
//       1. Bootstrap locks -- Used for a few locks available at library startup-shutdown time.
//          These do not require non-negative global thread ID's.
//       2. Internal RTL locks -- Used everywhere else in the RTL
//       3. User locks (includes critical sections)
//
// ----------------------------------------------------------------------------


// ============================================================================
// Lock implementations.
// ============================================================================


// ----------------------------------------------------------------------------
// Test and set locks.
//
// Non-nested test and set locks differ from the other lock kinds (except
// futex) in that we use the memory allocated by the compiler for the lock,
// rather than a pointer to it.
//
// On lin32, lin_32e, and win_32, the space allocated may be as small as 4
// bytes, so we have to use a lock table for nested locks, and avoid accessing
// the depth_locked field for non-nested locks.
//
// Information normally available to the tools, such as lock location,
// lock usage (normal lock vs. critical section), etc. is not available with
// test and set locks.
// ----------------------------------------------------------------------------

struct kmp_base_tas_lock {
    volatile kmp_int32 poll;         // 0 => unlocked
                                     // locked: (gtid+1) of owning thread
    kmp_int32          depth_locked; // depth locked, for nested locks only
};

typedef struct kmp_base_tas_lock kmp_base_tas_lock_t;

union kmp_tas_lock {
    kmp_base_tas_lock_t lk;
    kmp_lock_pool_t pool;   // make certain struct is large enough
    double lk_align;        // use worst case alignment
                            // no cache line padding
};

typedef union kmp_tas_lock kmp_tas_lock_t;

//
// Static initializer for test and set lock variables. Usage:
//    kmp_tas_lock_t xlock = KMP_TAS_LOCK_INITIALIZER( xlock );
//
#define KMP_TAS_LOCK_INITIALIZER( lock ) { { 0, 0 } }

extern void __kmp_acquire_tas_lock( kmp_tas_lock_t *lck, kmp_int32 gtid );
extern int __kmp_test_tas_lock( kmp_tas_lock_t *lck, kmp_int32 gtid );
extern void __kmp_release_tas_lock( kmp_tas_lock_t *lck, kmp_int32 gtid );
extern void __kmp_init_tas_lock( kmp_tas_lock_t *lck );
extern void __kmp_destroy_tas_lock( kmp_tas_lock_t *lck );

extern void __kmp_acquire_nested_tas_lock( kmp_tas_lock_t *lck, kmp_int32 gtid );
extern int __kmp_test_nested_tas_lock( kmp_tas_lock_t *lck, kmp_int32 gtid );
extern int __kmp_release_nested_tas_lock( kmp_tas_lock_t *lck, kmp_int32 gtid );
extern void __kmp_init_nested_tas_lock( kmp_tas_lock_t *lck );
extern void __kmp_destroy_nested_tas_lock( kmp_tas_lock_t *lck );

#define KMP_NESTED_LOCK_RELEASED 1
#define KMP_NESTED_LOCK_HELD 0


#if KMP_OS_LINUX && (KMP_ARCH_X86 || KMP_ARCH_X86_64)

// ----------------------------------------------------------------------------
// futex locks.  futex locks are only available on Linux* OS.
//
// Like non-nested test and set lock, non-nested futex locks use the memory
// allocated by the compiler for the lock, rather than a pointer to it.
//
// Information normally available to the tools, such as lock location,
// lock usage (normal lock vs. critical section), etc. is not available with
// test and set locks.  With non-nested futex locks, the lock owner is not
// even available.
// ----------------------------------------------------------------------------

struct kmp_base_futex_lock {
    volatile kmp_int32 poll;         // 0 => unlocked
                                     // 2*(gtid+1) of owning thread, 0 if unlocked
                                     // locked: (gtid+1) of owning thread
    kmp_int32          depth_locked; // depth locked, for nested locks only
};

typedef struct kmp_base_futex_lock kmp_base_futex_lock_t;

union kmp_futex_lock {
    kmp_base_futex_lock_t lk;
    kmp_lock_pool_t pool;   // make certain struct is large enough
    double lk_align;        // use worst case alignment
                            // no cache line padding
};

typedef union kmp_futex_lock kmp_futex_lock_t;

//
// Static initializer for futex lock variables. Usage:
//    kmp_futex_lock_t xlock = KMP_FUTEX_LOCK_INITIALIZER( xlock );
//
#define KMP_FUTEX_LOCK_INITIALIZER( lock ) { { 0, 0 } }

extern void __kmp_acquire_futex_lock( kmp_futex_lock_t *lck, kmp_int32 gtid );
extern int __kmp_test_futex_lock( kmp_futex_lock_t *lck, kmp_int32 gtid );
extern void __kmp_release_futex_lock( kmp_futex_lock_t *lck, kmp_int32 gtid );
extern void __kmp_init_futex_lock( kmp_futex_lock_t *lck );
extern void __kmp_destroy_futex_lock( kmp_futex_lock_t *lck );

extern void __kmp_acquire_nested_futex_lock( kmp_futex_lock_t *lck, kmp_int32 gtid );
extern int __kmp_test_nested_futex_lock( kmp_futex_lock_t *lck, kmp_int32 gtid );
extern int __kmp_release_nested_futex_lock( kmp_futex_lock_t *lck, kmp_int32 gtid );
extern void __kmp_init_nested_futex_lock( kmp_futex_lock_t *lck );
extern void __kmp_destroy_nested_futex_lock( kmp_futex_lock_t *lck );

#endif // KMP_OS_LINUX && (KMP_ARCH_X86 || KMP_ARCH_X86_64)


// ----------------------------------------------------------------------------
// Ticket locks.
// ----------------------------------------------------------------------------

struct kmp_base_ticket_lock {
    // `initialized' must be the first entry in the lock data structure!
    volatile union kmp_ticket_lock * initialized;  // points to the lock union if in initialized state
    ident_t const *     location;     // Source code location of omp_init_lock().
    volatile kmp_uint32 next_ticket;  // ticket number to give to next thread which acquires
    volatile kmp_uint32 now_serving;  // ticket number for thread which holds the lock
    volatile kmp_int32  owner_id;     // (gtid+1) of owning thread, 0 if unlocked
    kmp_int32           depth_locked; // depth locked, for nested locks only
    kmp_lock_flags_t    flags;        // lock specifics, e.g. critical section lock
};

typedef struct kmp_base_ticket_lock kmp_base_ticket_lock_t;

union KMP_ALIGN_CACHE kmp_ticket_lock {
    kmp_base_ticket_lock_t lk;       // This field must be first to allow static initializing.
    kmp_lock_pool_t pool;
    double                 lk_align; // use worst case alignment
    char                   lk_pad[ KMP_PAD( kmp_base_ticket_lock_t, CACHE_LINE ) ];
};

typedef union kmp_ticket_lock kmp_ticket_lock_t;

//
// Static initializer for simple ticket lock variables. Usage:
//    kmp_ticket_lock_t xlock = KMP_TICKET_LOCK_INITIALIZER( xlock );
// Note the macro argument. It is important to make var properly initialized.
//
#define KMP_TICKET_LOCK_INITIALIZER( lock ) { { (kmp_ticket_lock_t *) & (lock), NULL, 0, 0, 0, -1 } }

extern void __kmp_acquire_ticket_lock( kmp_ticket_lock_t *lck, kmp_int32 gtid );
extern int __kmp_test_ticket_lock( kmp_ticket_lock_t *lck, kmp_int32 gtid );
extern int __kmp_test_ticket_lock_with_cheks( kmp_ticket_lock_t *lck, kmp_int32 gtid );
extern void __kmp_release_ticket_lock( kmp_ticket_lock_t *lck, kmp_int32 gtid );
extern void __kmp_init_ticket_lock( kmp_ticket_lock_t *lck );
extern void __kmp_destroy_ticket_lock( kmp_ticket_lock_t *lck );

extern void __kmp_acquire_nested_ticket_lock( kmp_ticket_lock_t *lck, kmp_int32 gtid );
extern int __kmp_test_nested_ticket_lock( kmp_ticket_lock_t *lck, kmp_int32 gtid );
extern int __kmp_release_nested_ticket_lock( kmp_ticket_lock_t *lck, kmp_int32 gtid );
extern void __kmp_init_nested_ticket_lock( kmp_ticket_lock_t *lck );
extern void __kmp_destroy_nested_ticket_lock( kmp_ticket_lock_t *lck );


// ----------------------------------------------------------------------------
// Queuing locks.
// ----------------------------------------------------------------------------

struct kmp_base_queuing_lock {

    //  `initialized' must be the first entry in the lock data structure!
    volatile union kmp_queuing_lock *initialized; // Points to the lock union if in initialized state.

    ident_t const *     location;     // Source code location of omp_init_lock().

    KMP_ALIGN( 8 )                    // tail_id  must be 8-byte aligned!

    volatile kmp_int32  tail_id;      // (gtid+1) of thread at tail of wait queue, 0 if empty
                                      // Must be no padding here since head/tail used in 8-byte CAS
    volatile kmp_int32  head_id;      // (gtid+1) of thread at head of wait queue, 0 if empty
                                      // Decl order assumes little endian
    // bakery-style lock
    volatile kmp_uint32 next_ticket;  // ticket number to give to next thread which acquires
    volatile kmp_uint32 now_serving;  // ticket number for thread which holds the lock
    volatile kmp_int32  owner_id;     // (gtid+1) of owning thread, 0 if unlocked
    kmp_int32           depth_locked; // depth locked, for nested locks only

    kmp_lock_flags_t    flags;        // lock specifics, e.g. critical section lock
};

typedef struct kmp_base_queuing_lock kmp_base_queuing_lock_t;

KMP_BUILD_ASSERT( offsetof( kmp_base_queuing_lock_t, tail_id ) % 8 == 0 );

union KMP_ALIGN_CACHE kmp_queuing_lock {
    kmp_base_queuing_lock_t lk;       // This field must be first to allow static initializing.
    kmp_lock_pool_t pool;
    double                   lk_align; // use worst case alignment
    char                     lk_pad[ KMP_PAD( kmp_base_queuing_lock_t, CACHE_LINE ) ];
};

typedef union kmp_queuing_lock kmp_queuing_lock_t;

extern void __kmp_acquire_queuing_lock( kmp_queuing_lock_t *lck, kmp_int32 gtid );
extern int __kmp_test_queuing_lock( kmp_queuing_lock_t *lck, kmp_int32 gtid );
extern void __kmp_release_queuing_lock( kmp_queuing_lock_t *lck, kmp_int32 gtid );
extern void __kmp_init_queuing_lock( kmp_queuing_lock_t *lck );
extern void __kmp_destroy_queuing_lock( kmp_queuing_lock_t *lck );

#define OMPT_SUPPORT 1
#if OMPT_SUPPORT
/* expose this so that locks for atomics can be tagged as such */
extern void __kmp_set_queuing_lock_flags( kmp_queuing_lock_t *lck, kmp_lock_flags_t flags );
#endif

extern void __kmp_acquire_nested_queuing_lock( kmp_queuing_lock_t *lck, kmp_int32 gtid );
extern int __kmp_test_nested_queuing_lock( kmp_queuing_lock_t *lck, kmp_int32 gtid );
extern int __kmp_release_nested_queuing_lock( kmp_queuing_lock_t *lck, kmp_int32 gtid );
extern void __kmp_init_nested_queuing_lock( kmp_queuing_lock_t *lck );
extern void __kmp_destroy_nested_queuing_lock( kmp_queuing_lock_t *lck );


// ----------------------------------------------------------------------------
// DRDPA ticket locks.
// ----------------------------------------------------------------------------

struct kmp_base_drdpa_lock {
    //
    // All of the fields on the first cache line are only written when
    // initializing or reconfiguring the lock.  These are relatively rare
    // operations, so data from the first cache line will usually stay
    // resident in the cache of each thread trying to acquire the lock.
    //
    // initialized must be the first entry in the lock data structure!
    //
    KMP_ALIGN_CACHE

    volatile union kmp_drdpa_lock * initialized;    // points to the lock union if in initialized state
    ident_t const *                 location;       // Source code location of omp_init_lock().
    volatile struct kmp_lock_poll {
        kmp_uint64 poll;
    } * volatile polls;
    volatile kmp_uint64             mask;           // is 2**num_polls-1 for mod op
    kmp_uint64                      cleanup_ticket; // thread with cleanup ticket
    volatile struct kmp_lock_poll * old_polls;      // will deallocate old_polls
    kmp_uint32                      num_polls;      // must be power of 2

    //
    // next_ticket it needs to exist in a separate cache line, as it is
    // invalidated every time a thread takes a new ticket.
    //
    KMP_ALIGN_CACHE

    volatile kmp_uint64             next_ticket;

    //
    // now_serving is used to store our ticket value while we hold the lock.
    // It has a slighly different meaning in the DRDPA ticket locks (where
    // it is written by the acquiring thread) than it does in the simple
    // ticket locks (where it is written by the releasing thread).
    //
    // Since now_serving is only read an written in the critical section,
    // it is non-volatile, but it needs to exist on a separate cache line,
    // as it is invalidated at every lock acquire.
    //
    // Likewise, the vars used for nested locks (owner_id and depth_locked)
    // are only written by the thread owning the lock, so they are put in
    // this cache line.  owner_id is read by other threads, so it must be
    // declared volatile.
    //
    KMP_ALIGN_CACHE

    kmp_uint64                      now_serving;    // doesn't have to be volatile
    volatile kmp_uint32             owner_id;       // (gtid+1) of owning thread, 0 if unlocked
    kmp_int32                       depth_locked;   // depth locked
    kmp_lock_flags_t                flags;          // lock specifics, e.g. critical section lock
};

typedef struct kmp_base_drdpa_lock kmp_base_drdpa_lock_t;

union KMP_ALIGN_CACHE kmp_drdpa_lock {
    kmp_base_drdpa_lock_t lk;       // This field must be first to allow static initializing. */
    kmp_lock_pool_t pool;
    double                lk_align; // use worst case alignment
    char                  lk_pad[ KMP_PAD( kmp_base_drdpa_lock_t, CACHE_LINE ) ];
};

typedef union kmp_drdpa_lock kmp_drdpa_lock_t;

extern void __kmp_acquire_drdpa_lock( kmp_drdpa_lock_t *lck, kmp_int32 gtid );
extern int __kmp_test_drdpa_lock( kmp_drdpa_lock_t *lck, kmp_int32 gtid );
extern void __kmp_release_drdpa_lock( kmp_drdpa_lock_t *lck, kmp_int32 gtid );
extern void __kmp_init_drdpa_lock( kmp_drdpa_lock_t *lck );
extern void __kmp_destroy_drdpa_lock( kmp_drdpa_lock_t *lck );

extern void __kmp_acquire_nested_drdpa_lock( kmp_drdpa_lock_t *lck, kmp_int32 gtid );
extern int __kmp_test_nested_drdpa_lock( kmp_drdpa_lock_t *lck, kmp_int32 gtid );
extern int __kmp_release_nested_drdpa_lock( kmp_drdpa_lock_t *lck, kmp_int32 gtid );
extern void __kmp_init_nested_drdpa_lock( kmp_drdpa_lock_t *lck );
extern void __kmp_destroy_nested_drdpa_lock( kmp_drdpa_lock_t *lck );


// ============================================================================
// Lock purposes.
// ============================================================================


// ----------------------------------------------------------------------------
// Bootstrap locks.
// ----------------------------------------------------------------------------

// Bootstrap locks -- very few locks used at library initialization time.
// Bootstrap locks are currently implemented as ticket locks.
// They could also be implemented as test and set lock, but cannot be
// implemented with other lock kinds as they require gtids which are not
// available at initialization time.

typedef kmp_ticket_lock_t kmp_bootstrap_lock_t;

#define KMP_BOOTSTRAP_LOCK_INITIALIZER( lock ) KMP_TICKET_LOCK_INITIALIZER( (lock) )

inline void
__kmp_acquire_bootstrap_lock( kmp_bootstrap_lock_t *lck )
{
    __kmp_acquire_ticket_lock( lck, KMP_GTID_DNE );
}

inline int
__kmp_test_bootstrap_lock( kmp_bootstrap_lock_t *lck )
{
    return __kmp_test_ticket_lock( lck, KMP_GTID_DNE );
}

inline void
__kmp_release_bootstrap_lock( kmp_bootstrap_lock_t *lck )
{
    __kmp_release_ticket_lock( lck, KMP_GTID_DNE );
}

inline void
__kmp_init_bootstrap_lock( kmp_bootstrap_lock_t *lck )
{
    __kmp_init_ticket_lock( lck );
}

inline void
__kmp_destroy_bootstrap_lock( kmp_bootstrap_lock_t *lck )
{
    __kmp_destroy_ticket_lock( lck );
}


// ----------------------------------------------------------------------------
// Internal RTL locks.
// ----------------------------------------------------------------------------

//
// Internal RTL locks are also implemented as ticket locks, for now.
//
// FIXME - We should go through and figure out which lock kind works best for
// each internal lock, and use the type deeclaration and function calls for
// that explicit lock kind (and get rid of this section).
//

typedef kmp_ticket_lock_t kmp_lock_t;

inline void
__kmp_acquire_lock( kmp_lock_t *lck, kmp_int32 gtid )
{
    __kmp_acquire_ticket_lock( lck, gtid );
}

inline int
__kmp_test_lock( kmp_lock_t *lck, kmp_int32 gtid )
{
    return __kmp_test_ticket_lock( lck, gtid );
}

inline void
__kmp_release_lock( kmp_lock_t *lck, kmp_int32 gtid )
{
    __kmp_release_ticket_lock( lck, gtid );
}

inline void
__kmp_init_lock( kmp_lock_t *lck )
{
    __kmp_init_ticket_lock( lck );
}

inline void
__kmp_destroy_lock( kmp_lock_t *lck )
{
    __kmp_destroy_ticket_lock( lck );
}


// ----------------------------------------------------------------------------
// User locks.
// ----------------------------------------------------------------------------

//
// Do not allocate objects of type union kmp_user_lock!!!
// This will waste space unless __kmp_user_lock_kind == lk_drdpa.
// Instead, check the value of __kmp_user_lock_kind and allocate objects of
// the type of the appropriate union member, and cast their addresses to
// kmp_user_lock_p.
//

enum kmp_lock_kind {
    lk_default = 0,
    lk_tas,
#if KMP_OS_LINUX && (KMP_ARCH_X86 || KMP_ARCH_X86_64)
    lk_futex,
#endif
    lk_ticket,
    lk_queuing,
    lk_drdpa
};

typedef enum kmp_lock_kind kmp_lock_kind_t;

extern kmp_lock_kind_t __kmp_user_lock_kind;

union kmp_user_lock {
    kmp_tas_lock_t     tas;
#if KMP_OS_LINUX && (KMP_ARCH_X86 || KMP_ARCH_X86_64)
    kmp_futex_lock_t   futex;
#endif
    kmp_ticket_lock_t  ticket;
    kmp_queuing_lock_t queuing;
    kmp_drdpa_lock_t   drdpa;
    kmp_lock_pool_t    pool;
};

typedef union kmp_user_lock *kmp_user_lock_p;

extern size_t __kmp_base_user_lock_size;
extern size_t __kmp_user_lock_size;

extern kmp_int32 ( *__kmp_get_user_lock_owner_ )( kmp_user_lock_p lck );

inline kmp_int32
__kmp_get_user_lock_owner( kmp_user_lock_p lck )
{
    KMP_DEBUG_ASSERT( __kmp_get_user_lock_owner_ != NULL );
    return ( *__kmp_get_user_lock_owner_ )( lck );
}

extern void ( *__kmp_acquire_user_lock_with_checks_ )( kmp_user_lock_p lck, kmp_int32 gtid );

#define KMP_FSYNC_PREPARE(x) ((void)0)
#define KMP_FSYNC_ACQUIRED(x) ((void)0)

#if KMP_OS_LINUX && (KMP_ARCH_X86 || KMP_ARCH_X86_64)

#define __kmp_acquire_user_lock_with_checks(lck,gtid)                                           \
    if (__kmp_user_lock_kind == lk_tas) {                                                       \
        if ( __kmp_env_consistency_check ) {                                                    \
            char const * const func = "omp_set_lock";                                           \
            if ( ( sizeof ( kmp_tas_lock_t ) <= OMP_LOCK_T_SIZE )                               \
                && lck->tas.lk.depth_locked != -1 ) {                                           \
                KMP_FATAL( LockNestableUsedAsSimple, func );                                    \
            }                                                                                   \
            if ( ( gtid >= 0 ) && ( lck->tas.lk.poll - 1 == gtid ) ) {                          \
                KMP_FATAL( LockIsAlreadyOwned, func );                                          \
            }                                                                                   \
        }                                                                                       \
        if ( __sync_val_compare_and_swap( &(lck->tas.lk.poll), 0, gtid + 1 ) ) {                \
            kmp_uint32 spins;                                                                   \
            KMP_FSYNC_PREPARE( lck );                                                           \
            KMP_INIT_YIELD( spins );                                                            \
            if ( TCR_4(__kmp_nth) > (__kmp_avail_proc ? __kmp_avail_proc : __kmp_xproc) ) {     \
                KMP_YIELD( TRUE );                                                              \
            } else {                                                                            \
                KMP_YIELD_SPIN( spins );                                                        \
            }                                                                                   \
            while ( __sync_val_compare_and_swap( &(lck->tas.lk.poll), 0, gtid + 1 ) ) {         \
                if ( TCR_4(__kmp_nth) > (__kmp_avail_proc ? __kmp_avail_proc : __kmp_xproc) ) { \
                    KMP_YIELD( TRUE );                                                          \
                } else {                                                                        \
                    KMP_YIELD_SPIN( spins );                                                    \
                }                                                                               \
            }                                                                                   \
        }                                                                                       \
        KMP_FSYNC_ACQUIRED( lck );                                                              \
    } else {                                                                                    \
        KMP_DEBUG_ASSERT( __kmp_acquire_user_lock_with_checks_ != NULL );                       \
        ( *__kmp_acquire_user_lock_with_checks_ )( lck, gtid );                                 \
    }

#else
inline void
__kmp_acquire_user_lock_with_checks( kmp_user_lock_p lck, kmp_int32 gtid )
{
    KMP_DEBUG_ASSERT( __kmp_acquire_user_lock_with_checks_ != NULL );
    ( *__kmp_acquire_user_lock_with_checks_ )( lck, gtid );
}
#endif

extern int ( *__kmp_test_user_lock_with_checks_ )( kmp_user_lock_p lck, kmp_int32 gtid );

#if KMP_OS_LINUX && (KMP_ARCH_X86 || KMP_ARCH_X86_64)

#include "kmp_i18n.h"                       /* AC: KMP_FATAL definition */
extern int __kmp_env_consistency_check;     /* AC: copy from kmp.h here */
inline int
__kmp_test_user_lock_with_checks( kmp_user_lock_p lck, kmp_int32 gtid )
{
    if ( __kmp_user_lock_kind == lk_tas ) {
        if ( __kmp_env_consistency_check ) {
            char const * const func = "omp_test_lock";
            if ( ( sizeof ( kmp_tas_lock_t ) <= OMP_LOCK_T_SIZE )
                && lck->tas.lk.depth_locked != -1 ) {
                KMP_FATAL( LockNestableUsedAsSimple, func );
            }
        }
        return !__sync_val_compare_and_swap( &(lck->tas.lk.poll), 0, gtid + 1 );
    } else {
        KMP_DEBUG_ASSERT( __kmp_test_user_lock_with_checks_ != NULL );
        return ( *__kmp_test_user_lock_with_checks_ )( lck, gtid );
    }
}
#else
inline int
__kmp_test_user_lock_with_checks( kmp_user_lock_p lck, kmp_int32 gtid )
{
    KMP_DEBUG_ASSERT( __kmp_test_user_lock_with_checks_ != NULL );
    return ( *__kmp_test_user_lock_with_checks_ )( lck, gtid );
}
#endif

extern void ( *__kmp_release_user_lock_with_checks_ )( kmp_user_lock_p lck, kmp_int32 gtid );

inline void
__kmp_release_user_lock_with_checks( kmp_user_lock_p lck, kmp_int32 gtid )
{
    KMP_DEBUG_ASSERT( __kmp_release_user_lock_with_checks_ != NULL );
    ( *__kmp_release_user_lock_with_checks_ ) ( lck, gtid );
}

extern void ( *__kmp_init_user_lock_with_checks_ )( kmp_user_lock_p lck );

inline void
__kmp_init_user_lock_with_checks( kmp_user_lock_p lck )
{
    KMP_DEBUG_ASSERT( __kmp_init_user_lock_with_checks_ != NULL );
    ( *__kmp_init_user_lock_with_checks_ )( lck );
}

//
// We need a non-checking version of destroy lock for when the RTL is
// doing the cleanup as it can't always tell if the lock is nested or not.
//
extern void ( *__kmp_destroy_user_lock_ )( kmp_user_lock_p lck );

inline void
__kmp_destroy_user_lock( kmp_user_lock_p lck )
{
    KMP_DEBUG_ASSERT( __kmp_destroy_user_lock_ != NULL );
    ( *__kmp_destroy_user_lock_ )( lck );
}

extern void ( *__kmp_destroy_user_lock_with_checks_ )( kmp_user_lock_p lck );

inline void
__kmp_destroy_user_lock_with_checks( kmp_user_lock_p lck )
{
    KMP_DEBUG_ASSERT( __kmp_destroy_user_lock_with_checks_ != NULL );
    ( *__kmp_destroy_user_lock_with_checks_ )( lck );
}

extern void ( *__kmp_acquire_nested_user_lock_with_checks_ )( kmp_user_lock_p lck, kmp_int32 gtid );

#if KMP_OS_LINUX && (KMP_ARCH_X86 || KMP_ARCH_X86_64)

#define __kmp_acquire_nested_user_lock_with_checks(lck,gtid)                                        \
    if (__kmp_user_lock_kind == lk_tas) {                                                           \
        if ( __kmp_env_consistency_check ) {                                                        \
            char const * const func = "omp_set_nest_lock";                                          \
            if ( ( sizeof ( kmp_tas_lock_t ) <= OMP_NEST_LOCK_T_SIZE )                              \
                && lck->tas.lk.depth_locked == -1 ) {                                               \
                KMP_FATAL( LockSimpleUsedAsNestable, func );                                        \
            }                                                                                       \
        }                                                                                           \
        if ( lck->tas.lk.poll - 1 == gtid ) {                                                       \
            lck->tas.lk.depth_locked += 1;                                                          \
        } else {                                                                                    \
            if ( __sync_val_compare_and_swap( &(lck->tas.lk.poll), 0, gtid + 1 ) ) {                \
                kmp_uint32 spins;                                                                   \
                KMP_FSYNC_PREPARE( lck );                                                           \
                KMP_INIT_YIELD( spins );                                                            \
                if ( TCR_4(__kmp_nth) > (__kmp_avail_proc ? __kmp_avail_proc : __kmp_xproc) ) {     \
                    KMP_YIELD( TRUE );                                                              \
                } else {                                                                            \
                    KMP_YIELD_SPIN( spins );                                                        \
                }                                                                                   \
                while ( __sync_val_compare_and_swap( &(lck->tas.lk.poll), 0, gtid + 1 ) ) {         \
                    if ( TCR_4(__kmp_nth) > (__kmp_avail_proc ? __kmp_avail_proc : __kmp_xproc) ) { \
                        KMP_YIELD( TRUE );                                                          \
                    } else {                                                                        \
                        KMP_YIELD_SPIN( spins );                                                    \
                    }                                                                               \
                }                                                                                   \
            }                                                                                       \
            lck->tas.lk.depth_locked = 1;                                                           \
        }                                                                                           \
        KMP_FSYNC_ACQUIRED( lck );                                                                  \
    } else {                                                                                        \
        KMP_DEBUG_ASSERT( __kmp_acquire_nested_user_lock_with_checks_ != NULL );                    \
        ( *__kmp_acquire_nested_user_lock_with_checks_ )( lck, gtid );                              \
    }

#else
inline void
__kmp_acquire_nested_user_lock_with_checks( kmp_user_lock_p lck, kmp_int32 gtid )
{
    KMP_DEBUG_ASSERT( __kmp_acquire_nested_user_lock_with_checks_ != NULL );
    ( *__kmp_acquire_nested_user_lock_with_checks_ )( lck, gtid );
}
#endif

extern int ( *__kmp_test_nested_user_lock_with_checks_ )( kmp_user_lock_p lck, kmp_int32 gtid );

#if KMP_OS_LINUX && (KMP_ARCH_X86 || KMP_ARCH_X86_64)
inline int
__kmp_test_nested_user_lock_with_checks( kmp_user_lock_p lck, kmp_int32 gtid )
{
    if ( __kmp_user_lock_kind == lk_tas ) {
        int retval;
        if ( __kmp_env_consistency_check ) {
            char const * const func = "omp_test_nest_lock";
            if ( ( sizeof ( kmp_tas_lock_t ) <= OMP_NEST_LOCK_T_SIZE )
                && lck->tas.lk.depth_locked == -1 ) {
                KMP_FATAL( LockSimpleUsedAsNestable, func );
            }
        }
        KMP_DEBUG_ASSERT( gtid >= 0 );
        if ( lck->tas.lk.poll - 1 == gtid ) {   /* __kmp_get_tas_lock_owner( lck ) == gtid */
            return ++lck->tas.lk.depth_locked;  /* same owner, depth increased */
        }
        retval = !__sync_val_compare_and_swap( &(lck->tas.lk.poll), 0, gtid + 1 );
        if ( retval ) {
            KMP_MB();
            lck->tas.lk.depth_locked = 1;
        }
        return retval;
    } else {
        KMP_DEBUG_ASSERT( __kmp_test_nested_user_lock_with_checks_ != NULL );
        return ( *__kmp_test_nested_user_lock_with_checks_ )( lck, gtid );
    }
}
#else
inline int
__kmp_test_nested_user_lock_with_checks( kmp_user_lock_p lck, kmp_int32 gtid )
{
    KMP_DEBUG_ASSERT( __kmp_test_nested_user_lock_with_checks_ != NULL );
    return ( *__kmp_test_nested_user_lock_with_checks_ )( lck, gtid );
}
#endif

extern int ( *__kmp_release_nested_user_lock_with_checks_ )( kmp_user_lock_p lck, kmp_int32 gtid );

inline int
__kmp_release_nested_user_lock_with_checks( kmp_user_lock_p lck, kmp_int32 gtid )
{
    KMP_DEBUG_ASSERT( __kmp_release_nested_user_lock_with_checks_ != NULL );
    return ( *__kmp_release_nested_user_lock_with_checks_ )( lck, gtid );
}

extern void ( *__kmp_init_nested_user_lock_with_checks_ )( kmp_user_lock_p lck );

inline void __kmp_init_nested_user_lock_with_checks( kmp_user_lock_p lck )
{
    KMP_DEBUG_ASSERT( __kmp_init_nested_user_lock_with_checks_ != NULL );
    ( *__kmp_init_nested_user_lock_with_checks_ )( lck );
}

extern void ( *__kmp_destroy_nested_user_lock_with_checks_ )( kmp_user_lock_p lck );

inline void
__kmp_destroy_nested_user_lock_with_checks( kmp_user_lock_p lck )
{
    KMP_DEBUG_ASSERT( __kmp_destroy_nested_user_lock_with_checks_ != NULL );
    ( *__kmp_destroy_nested_user_lock_with_checks_ )( lck );
}

//
// user lock functions which do not necessarily exist for all lock kinds.
//
// The "set" functions usually have wrapper routines that check for a NULL set
// function pointer and call it if non-NULL.
//
// In some cases, it makes sense to have a "get" wrapper function check for a
// NULL get function pointer and return NULL / invalid value / error code if
// the function pointer is NULL.
//
// In other cases, the calling code really should differentiate between an
// unimplemented function and one that is implemented but returning NULL /
// invalied value.  If this is the case, no get function wrapper exists.
//

extern int ( *__kmp_is_user_lock_initialized_ )( kmp_user_lock_p lck );

// no set function; fields set durining local allocation

extern const ident_t * ( *__kmp_get_user_lock_location_ )( kmp_user_lock_p lck );

inline const ident_t *
__kmp_get_user_lock_location( kmp_user_lock_p lck )
{
    if ( __kmp_get_user_lock_location_  != NULL ) {
        return ( *__kmp_get_user_lock_location_ )( lck );
    }
    else {
        return NULL;
    }
}

extern void ( *__kmp_set_user_lock_location_ )( kmp_user_lock_p lck, const ident_t *loc );

inline void
__kmp_set_user_lock_location( kmp_user_lock_p lck, const ident_t *loc )
{
    if ( __kmp_set_user_lock_location_  != NULL ) {
        ( *__kmp_set_user_lock_location_ )( lck, loc );
    }
}

extern kmp_lock_flags_t ( *__kmp_get_user_lock_flags_ )( kmp_user_lock_p lck );

extern void ( *__kmp_set_user_lock_flags_ )( kmp_user_lock_p lck, kmp_lock_flags_t flags );

inline void
__kmp_set_user_lock_flags( kmp_user_lock_p lck, kmp_lock_flags_t flags )
{
    if ( __kmp_set_user_lock_flags_  != NULL ) {
        ( *__kmp_set_user_lock_flags_ )( lck, flags );
    }
}

//
// The fuction which sets up all of the vtbl pointers for kmp_user_lock_t.
//
extern void __kmp_set_user_lock_vptrs( kmp_lock_kind_t user_lock_kind );



// ----------------------------------------------------------------------------
// User lock table & lock allocation
// ----------------------------------------------------------------------------

/*
    On 64-bit Linux* OS (and OS X*) GNU compiler allocates only 4 bytems memory for lock variable, which
    is not enough to store a pointer, so we have to use lock indexes instead of pointers and
    maintain lock table to map indexes to pointers.


    Note: The first element of the table is not a pointer to lock! It is a pointer to previously
    allocated table (or NULL if it is the first table).

    Usage:

        if ( OMP_LOCK_T_SIZE < sizeof( <lock> ) ) { // or OMP_NEST_LOCK_T_SIZE
            Lock table is fully utilized. User locks are indexes, so table is
            used on user lock operation.
            Note: it may be the case (lin_32) that we don't need to use a lock
            table for regular locks, but do need the table for nested locks.
        }
        else {
            Lock table initialized but not actually used.
        }
*/

struct kmp_lock_table {
    kmp_lock_index_t  used;      // Number of used elements
    kmp_lock_index_t  allocated; // Number of allocated elements
    kmp_user_lock_p * table;     // Lock table.
};

typedef struct kmp_lock_table kmp_lock_table_t;

extern kmp_lock_table_t __kmp_user_lock_table;
extern kmp_user_lock_p __kmp_lock_pool;

struct kmp_block_of_locks {
    struct kmp_block_of_locks * next_block;
    void *                      locks;
};

typedef struct kmp_block_of_locks kmp_block_of_locks_t;

extern kmp_block_of_locks_t *__kmp_lock_blocks;
extern int __kmp_num_locks_in_block;

extern kmp_user_lock_p __kmp_user_lock_allocate( void **user_lock, kmp_int32 gtid, kmp_lock_flags_t flags = 0 );
extern void __kmp_user_lock_free( void **user_lock, kmp_int32 gtid, kmp_user_lock_p lck );
extern kmp_user_lock_p __kmp_lookup_user_lock( void **user_lock, char const *func );
extern void __kmp_cleanup_user_locks();

#define KMP_CHECK_USER_LOCK_INIT() \
        {                                                               \
            if ( ! TCR_4( __kmp_init_user_locks ) ) {                   \
                __kmp_acquire_bootstrap_lock( &__kmp_initz_lock );      \
                if ( ! TCR_4( __kmp_init_user_locks ) ) {               \
                    TCW_4( __kmp_init_user_locks, TRUE );               \
                }                                                       \
                __kmp_release_bootstrap_lock( &__kmp_initz_lock );      \
            }                                                           \
        }

#undef KMP_PAD
#undef KMP_GTID_DNE

#ifdef __cplusplus
} // extern "C"
#endif // __cplusplus

#endif /* KMP_LOCK_H */