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f7a9f785 | 1 | /* Copyright (C) 2006-2016 Free Software Foundation, Inc. |
679d83ba UD |
2 | This file is part of the GNU C Library. |
3 | ||
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. | |
8 | ||
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. | |
13 | ||
14 | You should have received a copy of the GNU Lesser General Public | |
59ba27a6 PE |
15 | License along with the GNU C Library; if not, see |
16 | <http://www.gnu.org/licenses/>. */ | |
679d83ba UD |
17 | |
18 | /* We define a special synchronization primitive for AIO. POSIX | |
19 | conditional variables would be ideal but the pthread_cond_*wait | |
20 | operations do not return on EINTR. This is a requirement for | |
21 | correct aio_suspend and lio_listio implementations. */ | |
22 | ||
23 | #include <assert.h> | |
f083450f | 24 | #include <nptl/pthreadP.h> |
a2f0363f | 25 | #include <futex-internal.h> |
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26 | |
27 | #define DONT_NEED_AIO_MISC_COND 1 | |
28 | ||
29 | #define AIO_MISC_NOTIFY(waitlist) \ | |
30 | do { \ | |
d052233c | 31 | if (*waitlist->counterp > 0 && --*waitlist->counterp == 0) \ |
a2f0363f | 32 | futex_wake ((unsigned int *) waitlist->counterp, 1, FUTEX_PRIVATE); \ |
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33 | } while (0) |
34 | ||
35 | #define AIO_MISC_WAIT(result, futex, timeout, cancel) \ | |
36 | do { \ | |
86edd44f RM |
37 | volatile unsigned int *futexaddr = &futex; \ |
38 | unsigned int oldval = futex; \ | |
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39 | \ |
40 | if (oldval != 0) \ | |
41 | { \ | |
42 | pthread_mutex_unlock (&__aio_requests_mutex); \ | |
43 | \ | |
44 | int oldtype; \ | |
45 | if (cancel) \ | |
46 | oldtype = LIBC_CANCEL_ASYNC (); \ | |
47 | \ | |
48 | int status; \ | |
49 | do \ | |
50 | { \ | |
a2f0363f TR |
51 | status = futex_reltimed_wait ((unsigned int *) futexaddr, oldval, \ |
52 | timeout, FUTEX_PRIVATE); \ | |
53 | if (status != EAGAIN) \ | |
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54 | break; \ |
55 | \ | |
04454efb | 56 | oldval = *futexaddr; \ |
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57 | } \ |
58 | while (oldval != 0); \ | |
59 | \ | |
60 | if (cancel) \ | |
61 | LIBC_CANCEL_RESET (oldtype); \ | |
62 | \ | |
a2f0363f | 63 | if (status == EINTR) \ |
679d83ba | 64 | result = EINTR; \ |
a2f0363f | 65 | else if (status == ETIMEDOUT) \ |
679d83ba UD |
66 | result = EAGAIN; \ |
67 | else \ | |
a2f0363f | 68 | assert (status == 0 || status == EAGAIN); \ |
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69 | \ |
70 | pthread_mutex_lock (&__aio_requests_mutex); \ | |
71 | } \ | |
72 | } while (0) | |
73 | ||
74 | #include_next <aio_misc.h> |