1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
|
/* Common definition for pthread_{timed,try}join{_np}.
Copyright (C) 2017-2026 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include "pthreadP.h"
#include <atomic.h>
#include <stap-probe.h>
#include <time.h>
#include <futex-internal.h>
int
__pthread_clockjoin_ex (pthread_t threadid, void **thread_return,
clockid_t clockid,
const struct __timespec64 *abstime,
bool cancel)
{
if (cancel)
__pthread_testcancel ();
struct pthread *pd = (struct pthread *) threadid;
/* Make sure the clock and time specified are valid. */
if (abstime
&& __glibc_unlikely (!futex_abstimed_supported_clockid (clockid)
|| ! valid_nanoseconds (abstime->tv_nsec)))
return EINVAL;
LIBC_PROBE (pthread_join, 1, threadid);
int result = 0;
unsigned int state;
while ((state = atomic_load_acquire (&pd->joinstate))
!= THREAD_STATE_EXITED)
{
struct pthread *self = THREAD_SELF;
if (pd == self
&& !cancel_enabled_and_canceled (self->cancelhandling))
return EDEADLK;
/* POSIX states calling pthread_join on a non joinable thread is
undefined. However, if PD is still in the cache we can warn
the caller. */
if (state == THREAD_STATE_DETACHED)
return EINVAL;
/* pthread_join is a cancellation entrypoint and we use the same
rationale for pthread_timedjoin_np.
The kernel notifies a process which uses CLONE_CHILD_CLEARTID via
a memory zeroing and futex wake-up when the process terminates.
The futex operation is not private. */
int ret = cancel
? __futex_abstimed_wait_cancelable64 (&pd->joinstate, state, clockid,
abstime, LLL_SHARED)
: __futex_abstimed_wait64 (&pd->joinstate, state, clockid, abstime,
LLL_SHARED);
if (ret == ETIMEDOUT || ret == EOVERFLOW)
{
result = ret;
break;
}
}
void *pd_result = pd->result;
if (__glibc_likely (result == 0))
{
if (thread_return != NULL)
*thread_return = pd_result;
/* Free the TCB. */
__nptl_free_tcb (pd);
}
LIBC_PROBE (pthread_join_ret, 3, threadid, result, pd_result);
return result;
}
|
