1 /* sem_wait -- wait on a semaphore. Generic futex-using version.
2 Copyright (C) 2003, 2007 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Paul Mackerras <paulus@au.ibm.com>, 2003.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, write to the Free
18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
23 #include <lowlevellock.h>
24 #include <internaltypes.h>
25 #include <semaphore.h>
28 #include <shlib-compat.h>
33 __sem_wait_cleanup (void *arg)
35 struct sparc_new_sem *isem = (struct sparc_new_sem *) arg;
38 atomic_decrement (&isem->nwaiters);
41 __sparc32_atomic_do_lock24 (&isem->lock);
43 __sparc32_atomic_do_unlock24 (&isem->lock);
49 __new_sem_wait (sem_t *sem)
51 struct sparc_new_sem *isem = (struct sparc_new_sem *) sem;
56 val = atomic_decrement_if_positive (&isem->value);
59 __sparc32_atomic_do_lock24 (&isem->lock);
62 isem->value = val - 1;
65 __sparc32_atomic_do_unlock24 (&isem->lock);
72 atomic_increment (&isem->nwaiters);
74 /* Already done above while still holding isem->lock. */;
76 pthread_cleanup_push (__sem_wait_cleanup, isem);
80 /* Enable asynchronous cancellation. Required by the standard. */
81 int oldtype = __pthread_enable_asynccancel ();
83 err = lll_futex_wait (&isem->value, 0,
84 isem->private ^ FUTEX_PRIVATE_FLAG);
86 /* Disable asynchronous cancellation. */
87 __pthread_disable_asynccancel (oldtype);
89 if (err != 0 && err != -EWOULDBLOCK)
97 val = atomic_decrement_if_positive (&isem->value);
100 __sparc32_atomic_do_lock24 (&isem->lock);
103 isem->value = val - 1;
104 __sparc32_atomic_do_unlock24 (&isem->lock);
114 pthread_cleanup_pop (0);
117 atomic_decrement (&isem->nwaiters);
120 __sparc32_atomic_do_lock24 (&isem->lock);
122 __sparc32_atomic_do_unlock24 (&isem->lock);
127 versioned_symbol (libpthread, __new_sem_wait, sem_wait, GLIBC_2_1);
130 #if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)
132 attribute_compat_text_section
133 __old_sem_wait (sem_t *sem)
135 struct sparc_old_sem *isem = (struct sparc_old_sem *) sem;
142 val = atomic_decrement_if_positive (&isem->value);
145 __sparc32_atomic_do_lock24 (&isem->lock);
148 isem->value = val - 1;
149 __sparc32_atomic_do_unlock24 (&isem->lock);
155 /* Enable asynchronous cancellation. Required by the standard. */
156 int oldtype = __pthread_enable_asynccancel ();
158 err = lll_futex_wait (&isem->value, 0,
159 isem->private ^ FUTEX_PRIVATE_FLAG);
161 /* Disable asynchronous cancellation. */
162 __pthread_disable_asynccancel (oldtype);
164 while (err == 0 || err == -EWOULDBLOCK);
170 compat_symbol (libpthread, __old_sem_wait, sem_wait, GLIBC_2_0);