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

#include "sync_utils.h"
#include "mutex.h"

/**
 * read_trylock - acquire a reader lock, or return immediately.
 * @ea: handle to effective address of lock variable.
 *
 * Acquire a non-exclusive reader lock, or return
 * immediately.  The only restriction here is that
 * @ea must be word aligned.
 *
 * Returns 1 on success, or 0 on failure.
 *
 * Context: The application should not call this interface 
 * from a tight loop!!  Use read_lock() instead.
 */
static __inline int _read_trylock(eaddr_t ea)
{
    DECL_MUTEX_VARS();
    s32 status, ret_val;

    RAW_TEST_AND_SET(>=, 1);

    return ret_val;
}


#endif /* _SPU_READ_TRYLOCK_H_ */