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/*

 * arch/alpha/lib/dec_and_lock.c

 *

 * ll/sc version of atomic_dec_and_lock()

 *

 */

#include <linux/spinlock.h>

#include <asm/atomic.h>

  asm (".text                                   \n\

        .global atomic_dec_and_lock             \n\

        .ent atomic_dec_and_lock                \n\

        .align  4                               \n\

atomic_dec_and_lock:                            \n\

        .prologue 0                             \n\

1:      ldl_l   $1, 0($16)                      \n\

        subl    $1, 1, $1                       \n\

        beq     $1, 2f                          \n\

        stl_c   $1, 0($16)                      \n\

        beq     $1, 4f                          \n\

        mb                                      \n\

        clr     $0                              \n\

        ret                                     \n\

2:      br      $29, 3f                         \n\

3:      ldgp    $29, 0($29)                     \n\

        br      $atomic_dec_and_lock_1..ng      \n\

        .subsection 2                           \n\

4:      br      1b                              \n\

        .previous                               \n\

        .end atomic_dec_and_lock");

static int __attribute__((unused))

atomic_dec_and_lock_1(atomic_t *atomic, spinlock_t *lock)

{

        /* Slow path */

        spin_lock(lock);

        if (atomic_dec_and_test(atomic))

                return 1;

        spin_unlock(lock);

        return 0;

}