[Fedora-directory-commits] ldapserver/ldap/servers/slapd slapi_counter.c, NONE, 1.1 slapi_counter_sunos_sparcv9.il, NONE, 1.1

Fri Oct 17 22:15:28 UTC 2008

Author: nkinder

Update of /cvs/dirsec/ldapserver/ldap/servers/slapd
In directory cvs1.fedora.phx.redhat.com:/tmp/cvs-serv11405/ldap/servers/slapd

Added Files:
	slapi_counter.c slapi_counter_sunos_sparcv9.il 
Log Message:
Related: 207457
Summary: Add 64-bit counter support (phase 1).

--- NEW FILE slapi_counter.c ---
/** BEGIN COPYRIGHT BLOCK
 * 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., 59 Temple
 * Place, Suite 330, Boston, MA 02111-1307 USA.
 * 
 * In addition, as a special exception, Red Hat, Inc. gives You the additional
 * right to link the code of this Program with code not covered under the GNU
 * General Public License ("Non-GPL Code") and to distribute linked combinations
 * including the two, subject to the limitations in this paragraph. Non-GPL Code
 * permitted under this exception must only link to the code of this Program
 * through those well defined interfaces identified in the file named EXCEPTION
 * found in the source code files (the "Approved Interfaces"). The files of
 * Non-GPL Code may instantiate templates or use macros or inline functions from
 * the Approved Interfaces without causing the resulting work to be covered by
 * the GNU General Public License. Only Red Hat, Inc. may make changes or
 * additions to the list of Approved Interfaces. You must obey the GNU General
 * Public License in all respects for all of the Program code and other code used
 * in conjunction with the Program except the Non-GPL Code covered by this
 * exception. If you modify this file, you may extend this exception to your
 * version of the file, but you are not obligated to do so. If you do not wish to
 * provide this exception without modification, you must delete this exception
 * statement from your version and license this file solely under the GPL without
 * exception. 
 * 
 * 
 * Copyright (C) 2008 Red Hat, Inc.
 * All rights reserved.
 * END COPYRIGHT BLOCK **/

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

#include "slap.h"

#ifdef HPUX
#ifdef ATOMIC_64BIT_OPERATIONS
#include <machine/sys/inline.h>
#endif
#endif
/*
 * Counter Structure
 */
typedef struct slapi_counter {
    PRUint64 value;
#ifndef ATOMIC_64BIT_OPERATIONS
    Slapi_Mutex *lock;
#endif
} slapi_counter;

/*
 * slapi_counter_new()
 *
 * Allocates and initializes a new Slapi_Counter.
 */
Slapi_Counter *slapi_counter_new()
{
    Slapi_Counter *counter = NULL;

    counter = (Slapi_Counter *)slapi_ch_calloc(1, sizeof(Slapi_Counter));

    if (counter != NULL) {
        slapi_counter_init(counter);
    }

    return counter;
}

/*
 * slapi_counter_init()
 *
 * Initializes a Slapi_Counter.
 */
void slapi_counter_init(Slapi_Counter *counter)
{
    if (counter != NULL) {
#ifndef ATOMIC_64BIT_OPERATIONS
        /* Create the lock if necessary. */
        if (counter->lock == NULL) {
            counter->lock = slapi_new_mutex();
        }
#endif

        /* Set the value to 0. */
        slapi_counter_set_value(counter, 0);
    }
}

/*
 * slapi_counter_destroy()
 *
 * Destroy's a Slapi_Counter and sets the
 * pointer to NULL to prevent reuse.
 */
void slapi_counter_destroy(Slapi_Counter **counter)
{
    if ((counter != NULL) && (*counter != NULL)) {
#ifndef ATOMIC_64BIT_OPERATIONS
        slapi_destroy_mutex((*counter)->lock);
#endif
        slapi_ch_free((void **)counter);
    }
}

/*
 * slapi_counter_increment()
 *
 * Atomically increments a Slapi_Counter.
 */
PRUint64 slapi_counter_increment(Slapi_Counter *counter)
{
    return slapi_counter_add(counter, 1);
}

/*
 * slapi_counter_decrement()
 *
 * Atomically decrements a Slapi_Counter. Note
 * that this will not prevent you from wrapping
 * around 0.
 */
PRUint64 slapi_counter_decrement(Slapi_Counter *counter)
{
    return slapi_counter_subtract(counter, 1);
}

/*
 * slapi_counter_add()
 *
 * Atomically add a value to a Slapi_Counter.
 */
PRUint64 slapi_counter_add(Slapi_Counter *counter, PRUint64 addvalue)
{
    PRUint64 newvalue = 0;
#ifdef HPUX
    PRUint64 prev = 0;
#endif

    if (counter == NULL) {
        return newvalue;
    }

#ifndef ATOMIC_64BIT_OPERATIONS
    slapi_lock_mutex(counter->lock);
    counter->value += addvalue;
    newvalue = counter->value;
    slapi_unlock_mutex(counter->lock);
#else
#ifdef LINUX
    newvalue = __sync_add_and_fetch(&(counter->value), addvalue);
#elif defined(SOLARIS)
    newvalue = _sparcv9_AtomicAdd_il(&(counter->value), addvalue);
#elif defined(HPUX)
    /* fetchadd only works with values of 1, 4, 8, and 16.  In addition, it requires
     * it's argument to be an integer constant. */
    if (addvalue == 1) {
        newvalue = _Asm_fetchadd(_FASZ_D, _SEM_ACQ, &(counter->value), 1, _LDHINT_NONE);
        newvalue += 1;
    } else if  (addvalue == 4) {
        newvalue = _Asm_fetchadd(_FASZ_D, _SEM_ACQ, &(counter->value), 4, _LDHINT_NONE);
        newvalue += 4;
    } else if (addvalue == 8) {
        newvalue = _Asm_fetchadd(_FASZ_D, _SEM_ACQ, &(counter->value), 8, _LDHINT_NONE);
        newvalue += 8;
    } else if (addvalue == 16) {
        newvalue = _Asm_fetchadd(_FASZ_D, _SEM_ACQ, &(counter->value), 16, _LDHINT_NONE);
        newvalue += 16;
    } else {
        /* For other values, we have to use cmpxchg. */
        do {
            prev = slapi_counter_get(counter);
            newvalue = prev + addvalue;
            /* Put prev in a register for cmpxchg to compare against */
           _Asm_mov_to_ar(_AREG_CCV, prev);
        } while (prev != _Asm_cmpxchg(_FASZ_D, _SEM_ACQ, &(counter->value), newvalue, _LDHINT_NONE));
    }
#endif
#endif /* ATOMIC_64BIT_OPERATIONS */

    return newvalue;
}

/*
 * slapi_counter_subtract()
 *
 * Atomically subtract a value from a Slapi_Counter.  Note
 * that this will not prevent you from wrapping around 0.
 */
PRUint64 slapi_counter_subtract(Slapi_Counter *counter, PRUint64 subvalue)
{
    PRUint64 newvalue = 0;
#ifdef HPUX
    PRUint64 prev = 0;
#endif

    if (counter == NULL) {
        return newvalue;
    }

#ifndef ATOMIC_64BIT_OPERATIONS
    slapi_lock_mutex(counter->lock);
    counter->value -= subvalue;
    newvalue = counter->value;
    slapi_unlock_mutex(counter->lock);
#else
#ifdef LINUX
    newvalue = __sync_sub_and_fetch(&(counter->value), subvalue);
#elif defined(SOLARIS)
    newvalue = _sparcv9_AtomicSub_il(&(counter->value), subvalue);
#elif defined(HPUX)
    /* fetchadd only works with values of -1, -4, -8, and -16.  In addition, it requires
     * it's argument to be an integer constant. */
    if (subvalue == 1) {
        newvalue = _Asm_fetchadd(_FASZ_D, _SEM_ACQ, &(counter->value), -1, _LDHINT_NONE);
        newvalue -= 1;
    } else if  (subvalue == 4) {
        newvalue = _Asm_fetchadd(_FASZ_D, _SEM_ACQ, &(counter->value), -4, _LDHINT_NONE);
        newvalue -= 4;
    } else if (subvalue == 8) {
        newvalue = _Asm_fetchadd(_FASZ_D, _SEM_ACQ, &(counter->value), -8, _LDHINT_NONE);
        newvalue -= 8;
    } else if (subvalue == 16) {
        newvalue = _Asm_fetchadd(_FASZ_D, _SEM_ACQ, &(counter->value), -16, _LDHINT_NONE);
        newvalue -= 16;
    } else {
        /* For other values, we have to use cmpxchg. */
        do {
            prev = slapi_counter_get(counter);
            newvalue = prev - subvalue;
            /* Put prev in a register for cmpxchg to compare against */
           _Asm_mov_to_ar(_AREG_CCV, prev);
        } while (prev != _Asm_cmpxchg(_FASZ_D, _SEM_ACQ, &(counter->value), newvalue, _LDHINT_NONE));
    }
#endif
#endif /* ATOMIC_64BIT_OPERATIONS */

    return newvalue;
}

/*
 * slapi_counter_set_value()
 *
 * Atomically sets the value of a Slapi_Counter.
 */
PRUint64 slapi_counter_set_value(Slapi_Counter *counter, PRUint64 newvalue)
{
    PRUint64 value = 0;

    if (counter == NULL) {
        return value;
    }

#ifndef ATOMIC_64BIT_OPERATIONS
    slapi_lock_mutex(counter->lock);
    counter->value = newvalue;
    slapi_unlock_mutex(counter->lock);
    return newvalue;
#else
#ifdef LINUX
    while (1) {
        value = counter->value;
        if (__sync_bool_compare_and_swap(&(counter->value), value, newvalue)) {
            return newvalue;
        }
    }
#elif defined(SOLARIS)
    _sparcv9_AtomicSet_il(&(counter->value), newvalue);
    return newvalue;
#elif defined(HPUX)
    do {
        value = counter->value;
        /* Put value in a register for cmpxchg to compare against */
        _Asm_mov_to_ar(_AREG_CCV, value);
    } while (value != _Asm_cmpxchg(_FASZ_D, _SEM_ACQ, &(counter->value), newvalue, _LDHINT_NONE));
    return newvalue;
#endif
#endif /* ATOMIC_64BIT_OPERATIONS */
}

/*
 * slapi_counter_get_value()
 *
 * Returns the value of a Slapi_Counter.
 */
PRUint64 slapi_counter_get_value(Slapi_Counter *counter)
{
    PRUint64 value = 0;

    if (counter == NULL) {
        return value;
    }

#ifndef ATOMIC_64BIT_OPERATIONS
    slapi_lock_mutex(counter->lock);
    value = counter->value;
    slapi_unlock_mutex(counter->lock);
#else
#ifdef LINUX
    while (1) {
        value = counter->value;
        if (__sync_bool_compare_and_swap(&(counter->value), value, value)) {
            break;
        }
    }
#elif defined(SOLARIS)
    while (1) {
        value = counter->value;
        if (value == _sparcv9_AtomicSet_il(&(counter->value), value)) {
            break;
        }
    }
#elif defined(HPUX)
    do {
        value = counter->value;
        /* Put value in a register for cmpxchg to compare against */
        _Asm_mov_to_ar(_AREG_CCV, value);
    } while (value != _Asm_cmpxchg(_FASZ_D, _SEM_ACQ, &(counter->value), value, _LDHINT_NONE));
#endif
#endif /* ATOMIC_64BIT_OPERATIONS */

    return value;
}

--- NEW FILE slapi_counter_sunos_sparcv9.il ---
// BEGIN COPYRIGHT BLOCK
// 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., 59 Temple
// Place, Suite 330, Boston, MA 02111-1307 USA.
// 
// In addition, as a special exception, Red Hat, Inc. gives You the additional
// right to link the code of this Program with code not covered under the GNU
// General Public License ("Non-GPL Code") and to distribute linked combinations
// including the two, subject to the limitations in this paragraph. Non-GPL Code
// permitted under this exception must only link to the code of this Program
// through those well defined interfaces identified in the file named EXCEPTION
// found in the source code files (the "Approved Interfaces"). The files of
// Non-GPL Code may instantiate templates or use macros or inline functions from
// the Approved Interfaces without causing the resulting work to be covered by
// the GNU General Public License. Only Red Hat, Inc. may make changes or
// additions to the list of Approved Interfaces. You must obey the GNU General
// Public License in all respects for all of the Program code and other code used
// in conjunction with the Program except the Non-GPL Code covered by this
// exception. If you modify this file, you may extend this exception to your
// version of the file, but you are not obligated to do so. If you do not wish to
// provide this exception without modification, you must delete this exception
// statement from your version and license this file solely under the GPL without
// exception. 
// 
// 
// The Original Code is the Netscape Portable Runtime (NSPR).
//
// The Initial Developer of the Original Code is
// Netscape Communications Corporation.
// Portions created by the Initial Developer are Copyright (C) 1998-2000
// the Initial Developer. All Rights Reserved.
//
// The original code has been modified to support 64-bit atomic increments by
// Red Hat, Inc.  These portions are Copyright (C) 2008 Red Hat, Inc. All Rights
// reserved.
//
// END COPYRIGHT BLOCK
//

//  ======================================================================
//
//  Perform the sequence a = b atomically with respect to other
//  fetch-and-stores to location a in a wait-free fashion.
//
//  usage : newval = _sparcv9_AtomicSet(address, newval)
//
//  -----------------------
//  Note on REGISTER USAGE:
//  as this is a LEAF procedure, a new stack frame is not created;
//  we use the caller's stack frame so what would normally be %i (input)
//  registers are actually %o (output registers).  Also, we must not
//  overwrite the contents of %l (local) registers as they are not
//  assumed to be volatile during calls.
//
//  So, the registers used are:
//     %o0  [input]   - the address of the value to set
//     %o1  [input]   - the new value to set for [%o0]
//     %o2  [local]   - work register
//     %o3  [local]   - work register
//  -----------------------

.inline _sparcv9_AtomicSet_il, 0
retryAS:
        ld      [%o0], %o2              ! set o2 to the current value
        mov     %o1, %o3                ! set up the new value
        casx    [%o0], %o2, %o3         ! atomically set if o0 hasn't changed
        cmp     %o2, %o3                ! see if we set the value
        bne     retryAS                 ! if not, try again
        nop                             ! empty out the branch pipeline
        retl                            ! return back to the caller
        mov     %o3, %o0                ! set the return code to the new value
.end

//  ======================================================================
//
//  Perform the sequence a = a + b atomically with respect to other
//  fetch-and-adds to location a in a wait-free fashion.
//
//  usage : newval = _sparcv9_AtomicAdd(address, val)
//  return: the value after addition
//

.inline _sparcv9_AtomicAdd_il, 0
retryAA:
        ld      [%o0], %o2              ! set o2 to the current value
        addx    %o2, %o1, %o3           ! calc the new value
        mov     %o3, %o4                ! save the return value
        casx    [%o0], %o2, %o3         ! atomically set if o0 hasn't changed
        cmp     %o2, %o3                ! see if we set the value
        bne     retryAA                 ! if not, try again
        nop                             ! empty out the branch pipeline
        retl                            ! return back to the caller
        mov     %o4, %o0                ! set the return code to the new value
.end

//  ======================================================================
//
//  Perform the sequence a = a - b atomically with respect to other
//  fetch-and-subs to location a in a wait-free fashion.
//
//  usage : newval = _sparcv9_AtomicSub(address, val)
//  return: the value after addition
//

.inline _sparcv9_AtomicSub_il, 0
retryAU:
        ld      [%o0], %o2              ! set o2 to the current value
        subx    %o2, %o1, %o3           ! calc the new value
        mov     %o3, %o4                ! save the return value
        casx    [%o0], %o2, %o3         ! atomically set if o0 hasn't changed
        cmp     %o2, %o3                ! see if we set the value
        bne     retryAU                 ! if not, try again
        nop                             ! empty out the branch pipeline
        retl                            ! return back to the caller
        mov     %o4, %o0                ! set the return code to the new value
.end