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/* -------------------------------------------------------------- */
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/* (C)Copyright 2001,2007, */
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/* International Business Machines Corporation, */
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/* Sony Computer Entertainment, Incorporated, */
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/* Toshiba Corporation, */
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/* All Rights Reserved. */
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/* Redistribution and use in source and binary forms, with or */
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/* without modification, are permitted provided that the */
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/* following conditions are met: */
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/* - Redistributions of source code must retain the above copyright*/
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/* notice, this list of conditions and the following disclaimer. */
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/* - Redistributions in binary form must reproduce the above */
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/* copyright notice, this list of conditions and the following */
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/* disclaimer in the documentation and/or other materials */
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/* provided with the distribution. */
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/* - Neither the name of IBM Corporation nor the names of its */
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/* contributors may be used to endorse or promote products */
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/* derived from this software without specific prior written */
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/* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND */
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/* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, */
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/* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF */
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/* -------------------------------------------------------------- */
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/* PROLOG END TAG zYx */
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#ifndef _SPU_ATOMIC_DEC_IF_POSITIVE_H_
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#define _SPU_ATOMIC_DEC_IF_POSITIVE_H_
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#include <sync_utils.h>
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* atomic_dec_if_positive - atomically decrement if counter is positive.
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* @v: handle to effective address of counter.
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* Atomically decrement a counter if its value is positive.
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* The only restriction is that @v must be word aligned.
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* Returns the old value of the counter, minus 1.
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static __inline int _atomic_dec_if_positive(atomic_ea_t v)
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ea64.ull = ALIGN128_EA(v);
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offset = OFFSET128_EA_U32(v);
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MFC_DMA(buf, ea64, size, tagid, MFC_GETLLAR_CMD);
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spu_readch(MFC_RdAtomicStat);
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ret_val = buf[offset] - 1;
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if (likely(ret_val >= 0)) {
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buf[offset] = ret_val;
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MFC_DMA(buf, ea64, size, tagid, MFC_PUTLLC_CMD);
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status = spu_readch(MFC_RdAtomicStat);
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MFC_DMA(buf, ea64, size, tagid, MFC_PUTLLC_CMD);
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spu_readch(MFC_RdAtomicStat);
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} while (status != 0);
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#endif /* _SPU_ATOMIC_DEC_IF_POSITIVE_H_ */