git://sourceware.org / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| 84060bad | 1 | /* pthread_getcpuclockid -- Get POSIX clockid_t for a pthread_t. Linux version |
| 93a78ac4 | 2 | Copyright (C) 2000-2012 Free Software Foundation, Inc. |
| 84060bad RM |
3 | This file is part of the GNU C Library. |
| 4 | ||
| 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 License as | |
| 7 | published by the Free Software Foundation; either version 2.1 of the | |
| 8 | License, or (at your option) any later version. | |
| 9 | ||
| 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. | |
| 14 | ||
| 15 | You should have received a copy of the GNU Lesser General Public | |
| 59ba27a6 PE |
16 | License along with the GNU C Library; see the file COPYING.LIB. If |
| 17 | not, see <http://www.gnu.org/licenses/>. */ | |
| 84060bad RM |
18 | |
| 19 | #include <errno.h> | |
| 20 | #include <pthreadP.h> | |
| 21 | #include <sys/time.h> | |
| 22 | #include <tls.h> | |
| 45bc95b5 UD |
23 | #include <kernel-features.h> |
| 24 | #include <kernel-posix-cpu-timers.h> | |
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25 | |
| 26 | ||
| 27 | #if !(__ASSUME_POSIX_CPU_TIMERS > 0) | |
| 28 | int __libc_missing_posix_cpu_timers attribute_hidden; | |
| 29 | #endif | |
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30 | |
| 31 | int | |
| 32 | pthread_getcpuclockid (threadid, clockid) | |
| 33 | pthread_t threadid; | |
| 34 | clockid_t *clockid; | |
| 35 | { | |
| 36 | struct pthread *pd = (struct pthread *) threadid; | |
| 37 | ||
| 38 | /* Make sure the descriptor is valid. */ | |
| 39 | if (INVALID_TD_P (pd)) | |
| 40 | /* Not a valid thread handle. */ | |
| 41 | return ESRCH; | |
| 42 | ||
| 43 | #ifdef __NR_clock_getres | |
| 44 | /* The clockid_t value is a simple computation from the TID. | |
| 45 | But we do a clock_getres call to validate it if we aren't | |
| 46 | yet sure we have the kernel support. */ | |
| 47 | ||
| 48 | const clockid_t tidclock = MAKE_THREAD_CPUCLOCK (pd->tid, CPUCLOCK_SCHED); | |
| 49 | ||
| 50 | # if !(__ASSUME_POSIX_CPU_TIMERS > 0) | |
| 84060bad RM |
51 | if (!__libc_missing_posix_cpu_timers) |
| 52 | { | |
| 53 | INTERNAL_SYSCALL_DECL (err); | |
| 54 | int r = INTERNAL_SYSCALL (clock_getres, err, 2, tidclock, NULL); | |
| 55 | if (!INTERNAL_SYSCALL_ERROR_P (r, err)) | |
| 56 | # endif | |
| 57 | { | |
| 58 | *clockid = tidclock; | |
| 59 | return 0; | |
| 60 | } | |
| 61 | ||
| 62 | # if !(__ASSUME_POSIX_CPU_TIMERS > 0) | |
| 93a78ac4 | 63 | if (INTERNAL_SYSCALL_ERRNO (r, err) == EINVAL) |
| 84060bad | 64 | { |
| 93a78ac4 | 65 | /* The kernel doesn't support these clocks at all. */ |
| 84060bad RM |
66 | __libc_missing_posix_cpu_timers = 1; |
| 67 | } | |
| 68 | else | |
| 84060bad RM |
69 | return INTERNAL_SYSCALL_ERRNO (r, err); |
| 70 | } | |
| 71 | # endif | |
| 72 | #endif | |
| 73 | ||
| 74 | #ifdef CLOCK_THREAD_CPUTIME_ID | |
| 75 | /* We need to store the thread ID in the CLOCKID variable together | |
| 76 | with a number identifying the clock. We reserve the low 3 bits | |
| 77 | for the clock ID and the rest for the thread ID. This is | |
| 78 | problematic if the thread ID is too large. But 29 bits should be | |
| 79 | fine. | |
| 80 | ||
| 81 | If some day more clock IDs are needed the ID part can be | |
| 82 | enlarged. The IDs are entirely internal. */ | |
| 83 | if (pd->tid >= 1 << (8 * sizeof (*clockid) - CLOCK_IDFIELD_SIZE)) | |
| 84 | return ERANGE; | |
| 85 | ||
| 86 | /* Store the number. */ | |
| 87 | *clockid = CLOCK_THREAD_CPUTIME_ID | (pd->tid << CLOCK_IDFIELD_SIZE); | |
| 88 | ||
| 89 | return 0; | |
| 90 | #else | |
| 91 | /* We don't have a timer for that. */ | |
| 92 | return ENOENT; | |
| 93 | #endif | |
| 94 | } |