1 /* Copyright (C) 2006-2014 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Jakub Jelinek <jakub@redhat.com>, 2006.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
21 #include <lowlevellock.h>
24 #include <kernel-features.h>
28 __lll_robust_lock_wait (int *futex
, int private)
31 int tid
= THREAD_GETMEM (THREAD_SELF
, tid
);
33 /* If the futex changed meanwhile try locking again. */
39 /* If the owner died, return the present value of the futex. */
40 if (__glibc_unlikely (oldval
& FUTEX_OWNER_DIED
))
43 /* Try to put the lock into state 'acquired, possibly with waiters'. */
44 int newval
= oldval
| FUTEX_WAITERS
;
46 && atomic_compare_and_exchange_bool_acq (futex
, newval
, oldval
))
49 /* If *futex == 2, wait until woken. */
50 lll_futex_wait (futex
, newval
, private);
55 while ((oldval
= atomic_compare_and_exchange_val_acq (futex
,
63 __lll_robust_timedlock_wait (int *futex
, const struct timespec
*abstime
,
66 /* Reject invalid timeouts. */
67 if (abstime
->tv_nsec
< 0 || abstime
->tv_nsec
>= 1000000000)
70 int tid
= THREAD_GETMEM (THREAD_SELF
, tid
);
73 /* If the futex changed meanwhile, try locking again. */
77 /* Work around the fact that the kernel rejects negative timeout values
78 despite them being valid. */
79 if (__glibc_unlikely (abstime
->tv_sec
< 0))
84 #if (!defined __ASSUME_FUTEX_CLOCK_REALTIME \
85 || !defined lll_futex_timed_wait_bitset)
89 /* Get the current time. */
90 (void) __gettimeofday (&tv
, NULL
);
92 /* Compute relative timeout. */
93 rt
.tv_sec
= abstime
->tv_sec
- tv
.tv_sec
;
94 rt
.tv_nsec
= abstime
->tv_nsec
- tv
.tv_usec
* 1000;
97 rt
.tv_nsec
+= 1000000000;
101 /* Already timed out? */
106 /* If the owner died, return the present value of the futex. */
107 if (__glibc_unlikely (oldval
& FUTEX_OWNER_DIED
))
110 /* Try to put the lock into state 'acquired, possibly with waiters'. */
111 int newval
= oldval
| FUTEX_WAITERS
;
113 && atomic_compare_and_exchange_bool_acq (futex
, newval
, oldval
))
116 /* If *futex == 2, wait until woken or timeout. */
117 #if (!defined __ASSUME_FUTEX_CLOCK_REALTIME \
118 || !defined lll_futex_timed_wait_bitset)
119 lll_futex_timed_wait (futex
, newval
, &rt
, private);
121 lll_futex_timed_wait_bitset (futex
, newval
, abstime
,
122 FUTEX_CLOCK_REALTIME
, private);
128 while ((oldval
= atomic_compare_and_exchange_val_acq (futex
,