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/* Copyright (C) 2003-2014 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#ifndef _LOWLEVELLOCK_H
#define _LOWLEVELLOCK_H 1
#ifndef __ASSEMBLER__
#include <time.h>
#include <sys/param.h>
#include <bits/pthreadtypes.h>
#include <kernel-features.h>
#endif
#define SYS_futex 240
#define FUTEX_WAIT 0
#define FUTEX_WAKE 1
#define FUTEX_CMP_REQUEUE 4
#define FUTEX_WAKE_OP 5
#define FUTEX_LOCK_PI 6
#define FUTEX_UNLOCK_PI 7
#define FUTEX_TRYLOCK_PI 8
#define FUTEX_WAIT_BITSET 9
#define FUTEX_WAKE_BITSET 10
#define FUTEX_PRIVATE_FLAG 128
#define FUTEX_CLOCK_REALTIME 256
#define FUTEX_BITSET_MATCH_ANY 0xffffffff
#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE ((4 << 24) | 1)
/* Values for 'private' parameter of locking macros. Yes, the
definition seems to be backwards. But it is not. The bit will be
reversed before passing to the system call. */
#define LLL_PRIVATE 0
#define LLL_SHARED FUTEX_PRIVATE_FLAG
#if !defined NOT_IN_libc || defined IS_IN_rtld
/* In libc.so or ld.so all futexes are private. */
# ifdef __ASSUME_PRIVATE_FUTEX
# define __lll_private_flag(fl, private) \
((fl) | FUTEX_PRIVATE_FLAG)
# else
# define __lll_private_flag(fl, private) \
((fl) | THREAD_GETMEM (THREAD_SELF, header.private_futex))
# endif
#else
# ifdef __ASSUME_PRIVATE_FUTEX
# define __lll_private_flag(fl, private) \
(((fl) | FUTEX_PRIVATE_FLAG) ^ (private))
# else
# define __lll_private_flag(fl, private) \
(__builtin_constant_p (private) \
? ((private) == 0 \
? ((fl) | THREAD_GETMEM (THREAD_SELF, header.private_futex)) \
: (fl)) \
: ((fl) | (((private) ^ FUTEX_PRIVATE_FLAG) \
& THREAD_GETMEM (THREAD_SELF, header.private_futex))))
# endif
#endif
#ifndef __ASSEMBLER__
/* Initializer for compatibility lock. */
#define LLL_LOCK_INITIALIZER (0)
#define LLL_LOCK_INITIALIZER_LOCKED (1)
#define LLL_LOCK_INITIALIZER_WAITERS (2)
extern int __lll_lock_wait_private (int val, int *__futex)
attribute_hidden;
extern int __lll_lock_wait (int val, int *__futex, int private)
attribute_hidden;
extern int __lll_timedlock_wait (int val, int *__futex,
const struct timespec *abstime, int private)
attribute_hidden;
extern int __lll_robust_lock_wait (int val, int *__futex, int private)
attribute_hidden;
extern int __lll_robust_timedlock_wait (int val, int *__futex,
const struct timespec *abstime,
int private)
attribute_hidden;
extern int __lll_unlock_wake_private (int *__futex) attribute_hidden;
extern int __lll_unlock_wake (int *__futex, int private) attribute_hidden;
#define lll_trylock(futex) \
({ unsigned char __result; \
__asm __volatile ("\
.align 2\n\
mova 1f,r0\n\
nop\n\
mov r15,r1\n\
mov #-8,r15\n\
0: mov.l @%1,r2\n\
cmp/eq r2,%3\n\
bf 1f\n\
mov.l %2,@%1\n\
1: mov r1,r15\n\
mov #-1,%0\n\
negc %0,%0"\
: "=r" (__result) \
: "r" (&(futex)), \
"r" (LLL_LOCK_INITIALIZER_LOCKED), \
"r" (LLL_LOCK_INITIALIZER) \
: "r0", "r1", "r2", "t", "memory"); \
__result; })
#define lll_cond_trylock(futex) \
({ unsigned char __result; \
__asm __volatile ("\
.align 2\n\
mova 1f,r0\n\
nop\n\
mov r15,r1\n\
mov #-8,r15\n\
0: mov.l @%1,r2\n\
cmp/eq r2,%3\n\
bf 1f\n\
mov.l %2,@%1\n\
1: mov r1,r15\n\
mov #-1,%0\n\
negc %0,%0"\
: "=r" (__result) \
: "r" (&(futex)), \
"r" (LLL_LOCK_INITIALIZER_WAITERS), \
"r" (LLL_LOCK_INITIALIZER) \
: "r0", "r1", "r2", "t", "memory"); \
__result; })
#define lll_lock(futex, private) \
(void) ({ int __result, *__futex = &(futex); \
__asm __volatile ("\
.align 2\n\
mova 1f,r0\n\
nop\n\
mov r15,r1\n\
mov #-8,r15\n\
0: mov.l @%2,%0\n\
tst %0,%0\n\
bf 1f\n\
mov.l %1,@%2\n\
1: mov r1,r15"\
: "=&r" (__result) : "r" (1), "r" (__futex) \
: "r0", "r1", "t", "memory"); \
if (__result) \
{ \
if (__builtin_constant_p (private) \
&& (private) == LLL_PRIVATE) \
__lll_lock_wait_private (__result, __futex); \
else \
__lll_lock_wait (__result, __futex, (private)); \
} \
})
#define lll_robust_lock(futex, id, private) \
({ int __result, *__futex = &(futex); \
__asm __volatile ("\
.align 2\n\
mova 1f,r0\n\
nop\n\
mov r15,r1\n\
mov #-8,r15\n\
0: mov.l @%2,%0\n\
tst %0,%0\n\
bf 1f\n\
mov.l %1,@%2\n\
1: mov r1,r15"\
: "=&r" (__result) : "r" (id), "r" (__futex) \
: "r0", "r1", "t", "memory"); \
if (__result) \
__result = __lll_robust_lock_wait (__result, __futex, private); \
__result; })
/* Special version of lll_mutex_lock which causes the unlock function to
always wakeup waiters. */
#define lll_cond_lock(futex, private) \
(void) ({ int __result, *__futex = &(futex); \
__asm __volatile ("\
.align 2\n\
mova 1f,r0\n\
nop\n\
mov r15,r1\n\
mov #-8,r15\n\
0: mov.l @%2,%0\n\
tst %0,%0\n\
bf 1f\n\
mov.l %1,@%2\n\
1: mov r1,r15"\
: "=&r" (__result) : "r" (2), "r" (__futex) \
: "r0", "r1", "t", "memory"); \
if (__result) \
__lll_lock_wait (__result, __futex, private); })
#define lll_robust_cond_lock(futex, id, private) \
({ int __result, *__futex = &(futex); \
__asm __volatile ("\
.align 2\n\
mova 1f,r0\n\
nop\n\
mov r15,r1\n\
mov #-8,r15\n\
0: mov.l @%2,%0\n\
tst %0,%0\n\
bf 1f\n\
mov.l %1,@%2\n\
1: mov r1,r15"\
: "=&r" (__result) : "r" (id | FUTEX_WAITERS), "r" (__futex) \
: "r0", "r1", "t", "memory"); \
if (__result) \
__result = __lll_robust_lock_wait (__result, __futex, private); \
__result; })
#define lll_timedlock(futex, timeout, private) \
({ int __result, *__futex = &(futex); \
__asm __volatile ("\
.align 2\n\
mova 1f,r0\n\
nop\n\
mov r15,r1\n\
mov #-8,r15\n\
0: mov.l @%2,%0\n\
tst %0,%0\n\
bf 1f\n\
mov.l %1,@%2\n\
1: mov r1,r15"\
: "=&r" (__result) : "r" (1), "r" (__futex) \
: "r0", "r1", "t", "memory"); \
if (__result) \
__result = __lll_timedlock_wait (__result, __futex, timeout, private); \
__result; })
#define lll_robust_timedlock(futex, timeout, id, private) \
({ int __result, *__futex = &(futex); \
__asm __volatile ("\
.align 2\n\
mova 1f,r0\n\
nop\n\
mov r15,r1\n\
mov #-8,r15\n\
0: mov.l @%2,%0\n\
tst %0,%0\n\
bf 1f\n\
mov.l %1,@%2\n\
1: mov r1,r15"\
: "=&r" (__result) : "r" (id), "r" (__futex) \
: "r0", "r1", "t", "memory"); \
if (__result) \
__result = __lll_robust_timedlock_wait (__result, __futex, \
timeout, private); \
__result; })
#define lll_unlock(futex, private) \
(void) ({ int __result, *__futex = &(futex); \
__asm __volatile ("\
.align 2\n\
mova 1f,r0\n\
mov r15,r1\n\
mov #-6,r15\n\
0: mov.l @%1,%0\n\
add #-1,%0\n\
mov.l %0,@%1\n\
1: mov r1,r15"\
: "=&r" (__result) : "r" (__futex) \
: "r0", "r1", "memory"); \
if (__result) \
{ \
if (__builtin_constant_p (private) \
&& (private) == LLL_PRIVATE) \
__lll_unlock_wake_private (__futex); \
else \
__lll_unlock_wake (__futex, (private)); \
} \
})
#define lll_robust_unlock(futex, private) \
(void) ({ int __result, *__futex = &(futex); \
__asm __volatile ("\
.align 2\n\
mova 1f,r0\n\
mov r15,r1\n\
mov #-6,r15\n\
0: mov.l @%1,%0\n\
and %2,%0\n\
mov.l %0,@%1\n\
1: mov r1,r15"\
: "=&r" (__result) : "r" (__futex), "r" (FUTEX_WAITERS) \
: "r0", "r1", "memory"); \
if (__result) \
__lll_unlock_wake (__futex, private); })
# ifdef NEED_SYSCALL_INST_PAD
# define SYSCALL_WITH_INST_PAD "\
trapa #0x14; or r0,r0; or r0,r0; or r0,r0; or r0,r0; or r0,r0"
# else
# define SYSCALL_WITH_INST_PAD "\
trapa #0x14"
# endif
#define lll_futex_wait(futex, val, private) \
lll_futex_timed_wait (futex, val, NULL, private)
#define lll_futex_timed_wait(futex, val, timeout, private) \
({ \
int __status; \
register unsigned long __r3 asm ("r3") = SYS_futex; \
register unsigned long __r4 asm ("r4") = (unsigned long) (futex); \
register unsigned long __r5 asm ("r5") \
= __lll_private_flag (FUTEX_WAIT, private); \
register unsigned long __r6 asm ("r6") = (unsigned long) (val); \
register unsigned long __r7 asm ("r7") = (timeout); \
__asm __volatile (SYSCALL_WITH_INST_PAD \
: "=z" (__status) \
: "r" (__r3), "r" (__r4), "r" (__r5), \
"r" (__r6), "r" (__r7) \
: "memory", "t"); \
__status; \
})
#define lll_futex_wake(futex, nr, private) \
do { \
int __ignore; \
register unsigned long __r3 asm ("r3") = SYS_futex; \
register unsigned long __r4 asm ("r4") = (unsigned long) (futex); \
register unsigned long __r5 asm ("r5") \
= __lll_private_flag (FUTEX_WAKE, private); \
register unsigned long __r6 asm ("r6") = (unsigned long) (nr); \
register unsigned long __r7 asm ("r7") = 0; \
__asm __volatile (SYSCALL_WITH_INST_PAD \
: "=z" (__ignore) \
: "r" (__r3), "r" (__r4), "r" (__r5), \
"r" (__r6), "r" (__r7) \
: "memory", "t"); \
} while (0)
#define lll_islocked(futex) \
(futex != LLL_LOCK_INITIALIZER)
/* The kernel notifies a process which uses CLONE_CHILD_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. */
#define lll_wait_tid(tid) \
do { \
__typeof (tid) *__tid = &(tid); \
while (*__tid != 0) \
lll_futex_wait (__tid, *__tid, LLL_SHARED); \
} 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; })
#endif /* !__ASSEMBLER__ */
#endif /* lowlevellock.h */
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