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/* -------------------------------------------------------------- */
/* (C)Copyright 2001,2007, */
/* International Business Machines Corporation, */
/* Sony Computer Entertainment, Incorporated, */
/* Toshiba 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 IBM 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 OWNER 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. */
/* -------------------------------------------------------------- */
/* PROLOG END TAG zYx */
#ifndef _SPU_ATOMIC_DEC_IF_POSITIVE_H_
#define _SPU_ATOMIC_DEC_IF_POSITIVE_H_
#include <sync_utils.h>
#include <atomic.h>
/**
* atomic_dec_if_positive - atomically decrement if counter is positive.
* @v: handle to effective address of counter.
*
* Atomically decrement a counter if its value is positive.
* The only restriction is that @v must be word aligned.
*
*
* Returns the old value of the counter, minus 1.
*/
static __inline int _atomic_dec_if_positive(atomic_ea_t v)
{
DECL_ATOMIC_VARS();
s32 status;
ea64.ull = ALIGN128_EA(v);
offset = OFFSET128_EA_U32(v);
do {
MFC_DMA(buf, ea64, size, tagid, MFC_GETLLAR_CMD);
spu_readch(MFC_RdAtomicStat);
ret_val = buf[offset] - 1;
if (likely(ret_val >= 0)) {
buf[offset] = ret_val;
MFC_DMA(buf, ea64, size, tagid, MFC_PUTLLC_CMD);
status = spu_readch(MFC_RdAtomicStat);
} else {
MFC_DMA(buf, ea64, size, tagid, MFC_PUTLLC_CMD);
spu_readch(MFC_RdAtomicStat);
status = 0;
break;
}
} while (status != 0);
return ret_val;
}
#endif /* _SPU_ATOMIC_DEC_IF_POSITIVE_H_ */
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