lowlevellock.h

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		      "jnz 1f\n\t"					      \
		      ".subsection 1\n\t"				      \
		      ".type  _L_robust_mutex_cond_lock_%=, @function\n"      \
		      "_L_robust_mutex_cond_lock_%=:\n"			      \
		      "1:\tleaq %2, %%rdi\n"				      \
		      "2:\tsubq $128, %%rsp\n"				      \
		      "3:\tcallq __lll_robust_mutex_lock_wait\n"	      \
		      "4:\taddq $128, %%rsp\n"				      \
		      "5:\tjmp 24f\n"					      \
		      "6:\t.size _L_robust_mutex_cond_lock_%=, 6b-1b\n\t"     \
		      ".previous\n"					      \
		      LLL_STUB_UNWIND_INFO_5				      \
		      "24:"						      \
		      : "=S" (ignore1), "=&D" (ignore2), "=m" (futex),	      \
			"=a" (result)					      \
		      : "0" (id | FUTEX_WAITERS), "m" (futex), "3" (0)	      \
		      : "cx", "r11", "cc", "memory");			      \
    result; })


#define lll_mutex_timedlock(futex, timeout) \
  ({ int result, ignore1, ignore2, ignore3;				      \
     __asm __volatile (LOCK_INSTR "cmpxchgl %2, %4\n\t"			      \
		       "jnz 1f\n\t"					      \
		       ".subsection 1\n\t"				      \
		       ".type  _L_mutex_timedlock_%=, @function\n"	      \
		       "_L_mutex_timedlock_%=:\n"			      \
		       "1:\tleaq %4, %%rdi\n"				      \
		       "0:\tmovq %8, %%rdx\n"				      \
		       "2:\tsubq $128, %%rsp\n"				      \
		       "3:\tcallq __lll_mutex_timedlock_wait\n"		      \
		       "4:\taddq $128, %%rsp\n"				      \
		       "5:\tjmp 24f\n"					      \
		       "6:\t.size _L_mutex_timedlock_%=, 6b-1b\n\t"	      \
		       ".previous\n"					      \
		       LLL_STUB_UNWIND_INFO_6				      \
		       "24:"						      \
		       : "=a" (result), "=&D" (ignore1), "=S" (ignore2),      \
			 "=&d" (ignore3), "=m" (futex)			      \
		       : "0" (0), "2" (1), "m" (futex), "m" (timeout)	      \
		       : "memory", "cx", "cc", "r10", "r11");		      \
     result; })


#define lll_robust_mutex_timedlock(futex, timeout, id) \
  ({ int result, ignore1, ignore2, ignore3;				      \
     __asm __volatile (LOCK_INSTR "cmpxchgl %2, %4\n\t"			      \
		       "jnz 1f\n\t"					      \
		       ".subsection 1\n\t"				      \
		       ".type  _L_robust_mutex_timedlock_%=, @function\n"     \
		       "_L_robust_mutex_timedlock_%=:\n"		      \
		       "1:\tleaq %4, %%rdi\n"				      \
		       "0:\tmovq %8, %%rdx\n"				      \
		       "2:\tsubq $128, %%rsp\n"				      \
		       "3:\tcallq __lll_robust_mutex_timedlock_wait\n"	      \
		       "4:\taddq $128, %%rsp\n"				      \
		       "5:\tjmp 24f\n"					      \
		       "6:\t.size _L_robust_mutex_timedlock_%=, 6b-1b\n\t"    \
		       ".previous\n"					      \
		       LLL_STUB_UNWIND_INFO_6				      \
		       "24:"						      \
		       : "=a" (result), "=&D" (ignore1), "=S" (ignore2),      \
			 "=&d" (ignore3), "=m" (futex)			      \
		       : "0" (0), "2" (id), "m" (futex), "m" (timeout)	      \
		       : "memory", "cx", "cc", "r10", "r11");		      \
     result; })


#define lll_mutex_unlock(futex) \
  (void) ({ int ignore;							      \
            __asm __volatile (LOCK_INSTR "decl %0\n\t"			      \
			      "jne 1f\n\t"				      \
			      ".subsection 1\n\t"			      \
			      ".type  _L_mutex_unlock_%=, @function\n"	      \
			      "_L_mutex_unlock_%=:\n"			      \
			      "1:\tleaq %0, %%rdi\n"			      \
			      "2:\tsubq $128, %%rsp\n"			      \
			      "3:\tcallq __lll_mutex_unlock_wake\n"	      \
			      "4:\taddq $128, %%rsp\n"			      \
			      "5:\tjmp 24f\n"				      \
			      "6:\t.size _L_mutex_unlock_%=, 6b-1b\n\t"	      \
			      ".previous\n"				      \
			      LLL_STUB_UNWIND_INFO_5			      \
			      "24:"					      \
			      : "=m" (futex), "=&D" (ignore)		      \
			      : "m" (futex)				      \
			      : "ax", "cx", "r11", "cc", "memory"); })


#define lll_robust_mutex_unlock(futex) \
  (void) ({ int ignore;							      \
	    __asm __volatile (LOCK_INSTR "andl %2, %0\n\t"		      \
			      "jne 1f\n\t"				      \
			      ".subsection 1\n\t"			      \
			      ".type  _L_robust_mutex_unlock_%=, @function\n" \
			      "_L_robust_mutex_unlock_%=:\n"		      \
			      "1:\tleaq %0, %%rdi\n"			      \
			      "2:\tsubq $128, %%rsp\n"			      \
			      "3:\tcallq __lll_mutex_unlock_wake\n"	      \
			      "4:\taddq $128, %%rsp\n"			      \
			      "5:\tjmp 24f\n"				      \
			      "6:\t.size _L_robust_mutex_unlock_%=, 6b-1b\n\t"\
			      ".previous\n"				      \
			      LLL_STUB_UNWIND_INFO_5			      \
			      "24:"					      \
			      : "=m" (futex), "=&D" (ignore)		      \
			      : "i" (FUTEX_WAITERS), "m" (futex)	      \
			      : "ax", "cx", "r11", "cc", "memory"); })


#define lll_robust_mutex_dead(futex) \
  (void) ({ int ignore;		     \
	    __asm __volatile (LOCK_INSTR "orl %3, (%2)\n\t"		      \
			      "syscall"					      \
			      : "=m" (futex), "=a" (ignore)		      \
			      : "D" (&(futex)), "i" (FUTEX_OWNER_DIED),	      \
				"S" (FUTEX_WAKE), "1" (__NR_futex),	      \
				"d" (1)					      \
			      : "cx", "r11", "cc", "memory"); })


/* Returns non-zero if error happened, zero if success.  */
#define lll_futex_requeue(ftx, nr_wake, nr_move, mutex, val) \
  ({ int __res;								      \
     register int __nr_move __asm ("r10") = nr_move;			      \
     register void *__mutex __asm ("r8") = mutex;			      \
     register int __val __asm ("r9") = val;				      \
     __asm __volatile ("syscall"					      \
		       : "=a" (__res)					      \
		       : "0" (__NR_futex), "D" ((void *) ftx),		      \
		         "S" (FUTEX_CMP_REQUEUE), "d" (nr_wake),	      \
		         "r" (__nr_move), "r" (__mutex), "r" (__val)	      \
		       : "cx", "r11", "cc", "memory");			      \
     __res < 0; })


#define lll_mutex_islocked(futex) \
  (futex != LLL_MUTEX_LOCK_INITIALIZER)


/* We have a separate internal lock implementation which is not tied
   to binary compatibility.  */

/* Type for lock object.  */
typedef int lll_lock_t;

/* Initializers for lock.  */
#define LLL_LOCK_INITIALIZER		(0)
#define LLL_LOCK_INITIALIZER_LOCKED	(1)


extern int lll_unlock_wake_cb (int *__futex) attribute_hidden;


/* The states of a lock are:
    0  -  untaken
    1  -  taken by one user
    2  -  taken by more users */


#if defined NOT_IN_libc || defined UP
# define lll_trylock(futex) lll_mutex_trylock (futex)
# define lll_lock(futex) lll_mutex_lock (futex)
# define lll_unlock(futex) lll_mutex_unlock (futex)
#else
/* Special versions of the macros for use in libc itself.  They avoid
   the lock prefix when the thread library is not used.

   The code sequence to avoid unnecessary lock prefixes is what the AMD
   guys suggested.  If you do not like it, bring it up with AMD.

   XXX In future we might even want to avoid it on UP machines.  */

# define lll_trylock(futex) \
  ({ unsigned char ret;							      \
     __asm __volatile ("cmpl $0, __libc_multiple_threads(%%rip)\n\t"	      \
		       "je 0f\n\t"					      \
		       "lock; cmpxchgl %2, %1\n\t"			      \
		       "jmp 1f\n"					      \
		       "0:\tcmpxchgl %2, %1\n\t"			      \
		       "1:setne %0"					      \
		       : "=a" (ret), "=m" (futex)			      \
		       : "r" (LLL_MUTEX_LOCK_INITIALIZER_LOCKED), "m" (futex),\
			 "0" (LLL_MUTEX_LOCK_INITIALIZER)		      \
		       : "memory");					      \
     ret; })


# define lll_lock(futex) \
  (void) ({ int ignore1, ignore2, ignore3;				      \
	    __asm __volatile ("cmpl $0, __libc_multiple_threads(%%rip)\n\t"   \
			      "je 0f\n\t"				      \
			      "lock; cmpxchgl %0, %2\n\t"		      \
			      "jnz 1f\n\t"				      \
		  	      "jmp 24f\n"				      \
			      "0:\tcmpxchgl %0, %2\n\t"			      \
			      "jnz 1f\n\t"				      \
			      ".subsection 1\n\t"			      \
			      ".type  _L_lock_%=, @function\n"		      \
			      "_L_lock_%=:\n"				      \
			      "1:\tleaq %2, %%rdi\n"			      \
			      "2:\tsubq $128, %%rsp\n"			      \
			      "3:\tcallq __lll_mutex_lock_wait\n"	      \
			      "4:\taddq $128, %%rsp\n"			      \
			      "5:\tjmp 24f\n"				      \
			      "6:\t.size _L_lock_%=, 6b-1b\n\t"		      \
			      ".previous\n"				      \
			      LLL_STUB_UNWIND_INFO_5			      \
			      "24:"					      \
			      : "=S" (ignore1), "=&D" (ignore2), "=m" (futex),\
				"=a" (ignore3)				      \
			      : "0" (1), "m" (futex), "3" (0)		      \
			      : "cx", "r11", "cc", "memory"); })


# define lll_unlock(futex) \
  (void) ({ int ignore;							      \
            __asm __volatile ("cmpl $0, __libc_multiple_threads(%%rip)\n\t"   \
			      "je 0f\n\t"				      \
			      "lock; decl %0\n\t"			      \
			      "jne 1f\n\t"				      \
		  	      "jmp 24f\n"				      \
			      "0:\tdecl %0\n\t"				      \
			      "jne 1f\n\t"				      \
			      ".subsection 1\n\t"			      \
			      ".type  _L_unlock_%=, @function\n"	      \
			      "_L_unlock_%=:\n"				      \
			      "1:\tleaq %0, %%rdi\n"			      \
			      "2:\tsubq $128, %%rsp\n"			      \
			      "3:\tcallq __lll_mutex_unlock_wake\n"	      \
			      "4:\taddq $128, %%rsp\n"			      \
			      "5:\tjmp 24f\n"				      \
			      "6:\t.size _L_unlock_%=, 6b-1b\n\t"	      \
			      ".previous\n"				      \
			      LLL_STUB_UNWIND_INFO_5			      \
			      "24:"					      \
			      : "=m" (futex), "=&D" (ignore)		      \
			      : "m" (futex)				      \
			      : "ax", "cx", "r11", "cc", "memory"); })
#endif


#define lll_islocked(futex) \
  (futex != LLL_MUTEX_LOCK_INITIALIZER)


/* The kernel notifies a process with uses CLONE_CLEARTID via futex
   wakeup when the clone terminates.  The memory location contains the
   thread ID while the clone is running and is reset to zero
   afterwards.

   The macro parameter must not have any side effect.  */
#define lll_wait_tid(tid) \
  do {									      \
    int __ignore;							      \
    register __typeof (tid) _tid asm ("edx") = (tid);			      \
    if (_tid != 0)							      \
      __asm __volatile ("xorq %%r10, %%r10\n\t"				      \
			"1:\tmovq %2, %%rax\n\t"			      \
			"syscall\n\t"					      \
			"cmpl $0, (%%rdi)\n\t"				      \
			"jne 1b"					      \
			: "=&a" (__ignore)				      \
			: "S" (FUTEX_WAIT), "i" (SYS_futex), "D" (&tid),      \
			  "d" (_tid)					      \
			: "memory", "cc", "r10", "r11", "cx");		      \
  } while (0)

extern int __lll_timedwait_tid (int *tid, const struct timespec *abstime)
     attribute_hidden;
#define lll_timedwait_tid(tid, abstime) \
  ({									      \
    int __result = 0;							      \
    if (tid != 0)							      \
      {									      \
	if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000)	      \
	  __result = EINVAL;						      \
	else								      \
	  __result = __lll_timedwait_tid (&tid, abstime);		      \
      }									      \
    __result; })


/* Conditional variable handling.  */

extern void __lll_cond_wait (pthread_cond_t *cond) attribute_hidden;
extern int __lll_cond_timedwait (pthread_cond_t *cond,
				 const struct timespec *abstime)
     attribute_hidden;
extern void __lll_cond_wake (pthread_cond_t *cond) attribute_hidden;
extern void __lll_cond_broadcast (pthread_cond_t *cond) attribute_hidden;


#define lll_cond_wait(cond) \
  __lll_cond_wait (cond)
#define lll_cond_timedwait(cond, abstime) \
  __lll_cond_timedwait (cond, abstime)
#define lll_cond_wake(cond) \
  __lll_cond_wake (cond)
#define lll_cond_broadcast(cond) \
  __lll_cond_broadcast (cond)


#endif	/* lowlevellock.h */