atomic_read.h

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/* PROLOG END TAG zYx                                              */
#ifndef _SPU_ATOMIC_READ_H_
#define _SPU_ATOMIC_READ_H_

#include <sync_utils.h>
#include <atomic.h>

/**
 * atomic_read - read an atomic counter.
 * @v: handle to effective address of counter.
 *
 * Read the current value of an atomic counter.
 */
static __inline int _atomic_read(atomic_ea_t v)
{
    DECL_ATOMIC_VARS();

    /* reserve a tag for use */
    tagid = mfc_tag_reserve();

    u32 oldtmask, tagmask = 1 << (tagid & 31);

    ea64.ull = ALIGN128_EA(v);
    offset = OFFSET128_EA_U32(v);

    MFC_DMA(buf, ea64, size, tagid & 31, MFC_GET_CMD);
    oldtmask = spu_readch(MFC_RdTagMask);
    spu_writech(MFC_WrTagMask, tagmask);
    spu_writech(MFC_WrTagUpdate, MFC_TAG_UPDATE_ANY);
    spu_readch(MFC_RdTagStat);
    spu_writech(MFC_WrTagMask, oldtmask);

    mfc_tag_release (tagid);
    ret_val =  buf[offset];
    return ret_val;
}


#endif /* _SPU_ATOMIC_READ_H_ */