projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| b168057a | 1 | /* Copyright (C) 2006-2015 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> |
| 679d83ba UD |
25 | #include <lowlevellock.h> |
| 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) \ |
| 085a4412 | 32 | lll_futex_wake (waitlist->counterp, 1, LLL_PRIVATE); \ |
| 679d83ba UD |
33 | } while (0) |
| 34 | ||
| 35 | #define AIO_MISC_WAIT(result, futex, timeout, cancel) \ | |
| 36 | do { \ | |
| 04454efb | 37 | volatile int *futexaddr = &futex; \ |
| 679d83ba UD |
38 | int oldval = futex; \ |
| 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 | { \ | |
| 085a4412 UD |
51 | status = lll_futex_timed_wait (futexaddr, oldval, timeout, \ |
| 52 | LLL_PRIVATE); \ | |
| 679d83ba UD |
53 | if (status != -EWOULDBLOCK) \ |
| 54 | break; \ | |
| 55 | \ | |
| 04454efb | 56 | oldval = *futexaddr; \ |
| 679d83ba UD |
57 | } \ |
| 58 | while (oldval != 0); \ | |
| 59 | \ | |
| 60 | if (cancel) \ | |
| 61 | LIBC_CANCEL_RESET (oldtype); \ | |
| 62 | \ | |
| 63 | if (status == -EINTR) \ | |
| 64 | result = EINTR; \ | |
| 65 | else if (status == -ETIMEDOUT) \ | |
| 66 | result = EAGAIN; \ | |
| 67 | else \ | |
| 68 | assert (status == 0 || status == -EWOULDBLOCK); \ | |
| 69 | \ | |
| 70 | pthread_mutex_lock (&__aio_requests_mutex); \ | |
| 71 | } \ | |
| 72 | } while (0) | |
| 73 | ||
| 74 | #include_next <aio_misc.h> |