1 /* Copyright (C) 2006, 2007 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19 /* We define a special synchronization primitive for AIO. POSIX
20 conditional variables would be ideal but the pthread_cond_*wait
21 operations do not return on EINTR. This is a requirement for
22 correct aio_suspend and lio_listio implementations. */
26 #include <lowlevellock.h>
28 #define DONT_NEED_AIO_MISC_COND 1
30 #define AIO_MISC_NOTIFY(waitlist) \
32 if (*waitlist->counterp > 0 && --*waitlist->counterp == 0) \
33 lll_futex_wake (waitlist->counterp, 1, LLL_PRIVATE); \
36 #define AIO_MISC_WAIT(result, futex, timeout, cancel) \
38 volatile int *futexaddr = &futex; \
43 pthread_mutex_unlock (&__aio_requests_mutex); \
47 oldtype = LIBC_CANCEL_ASYNC (); \
52 status = lll_futex_timed_wait (futexaddr, oldval, timeout, \
54 if (status != -EWOULDBLOCK) \
57 oldval = *futexaddr; \
59 while (oldval != 0); \
62 LIBC_CANCEL_RESET (oldtype); \
64 if (status == -EINTR) \
66 else if (status == -ETIMEDOUT) \
69 assert (status == 0 || status == -EWOULDBLOCK); \
71 pthread_mutex_lock (&__aio_requests_mutex); \
75 #include_next <aio_misc.h>