1 /* Copyright (C) 2002-2015 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
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.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
23 #include <stdio_ext.h>
26 #include <sys/resource.h>
28 #include <lowlevellock.h>
33 pthread_getattr_np (pthread_t thread_id
, pthread_attr_t
*attr
)
35 struct pthread
*thread
= (struct pthread
*) thread_id
;
36 struct pthread_attr
*iattr
= (struct pthread_attr
*) attr
;
39 lll_lock (thread
->lock
, LLL_PRIVATE
);
41 /* The thread library is responsible for keeping the values in the
42 thread desriptor up-to-date in case the user changes them. */
43 memcpy (&iattr
->schedparam
, &thread
->schedparam
,
44 sizeof (struct sched_param
));
45 iattr
->schedpolicy
= thread
->schedpolicy
;
47 /* Clear the flags work. */
48 iattr
->flags
= thread
->flags
;
50 /* The thread might be detached by now. */
51 if (IS_DETACHED (thread
))
52 iattr
->flags
|= ATTR_FLAG_DETACHSTATE
;
54 /* This is the guardsize after adjusting it. */
55 iattr
->guardsize
= thread
->reported_guardsize
;
57 /* The sizes are subject to alignment. */
58 if (__glibc_likely (thread
->stackblock
!= NULL
))
60 iattr
->stacksize
= thread
->stackblock_size
;
61 iattr
->stackaddr
= (char *) thread
->stackblock
+ iattr
->stacksize
;
65 /* No stack information available. This must be for the initial
66 thread. Get the info in some magical way. */
67 assert (abs (thread
->pid
) == thread
->tid
);
69 /* Stack size limit. */
72 /* The safest way to get the top of the stack is to read
73 /proc/self/maps and locate the line into which
74 __libc_stack_end falls. */
75 FILE *fp
= fopen ("/proc/self/maps", "rce");
78 /* We need the limit of the stack in any case. */
81 if (getrlimit (RLIMIT_STACK
, &rl
) != 0)
85 /* We consider the main process stack to have ended with
86 the page containing __libc_stack_end. There is stuff below
87 it in the stack too, like the program arguments, environment
88 variables and auxv info, but we ignore those pages when
89 returning size so that the output is consistent when the
90 stack is marked executable due to a loaded DSO requiring
92 void *stack_end
= (void *) ((uintptr_t) __libc_stack_end
93 & -(uintptr_t) GLRO(dl_pagesize
));
95 stack_end
+= GLRO(dl_pagesize
);
97 /* We need no locking. */
98 __fsetlocking (fp
, FSETLOCKING_BYCALLER
);
100 /* Until we found an entry (which should always be the case)
101 mark the result as a failure. */
106 uintptr_t last_to
= 0;
108 while (! feof_unlocked (fp
))
110 if (__getdelim (&line
, &linelen
, '\n', fp
) <= 0)
115 if (sscanf (line
, "%" SCNxPTR
"-%" SCNxPTR
, &from
, &to
) != 2)
117 if (from
<= (uintptr_t) __libc_stack_end
118 && (uintptr_t) __libc_stack_end
< to
)
120 /* Found the entry. Now we have the info we need. */
121 iattr
->stackaddr
= stack_end
;
123 rl
.rlim_cur
- (size_t) (to
- (uintptr_t) stack_end
);
125 /* Cut it down to align it to page size since otherwise we
126 risk going beyond rlimit when the kernel rounds up the
127 stack extension request. */
128 iattr
->stacksize
= (iattr
->stacksize
129 & -(intptr_t) GLRO(dl_pagesize
));
131 /* The limit might be too high. */
132 if ((size_t) iattr
->stacksize
133 > (size_t) iattr
->stackaddr
- last_to
)
134 iattr
->stacksize
= (size_t) iattr
->stackaddr
- last_to
;
136 /* We succeed and no need to look further. */
150 iattr
->flags
|= ATTR_FLAG_STACKADDR
;
155 cpu_set_t
*cpuset
= NULL
;
161 void *newp
= realloc (cpuset
, size
);
167 cpuset
= (cpu_set_t
*) newp
;
169 ret
= __pthread_getaffinity_np (thread_id
, size
, cpuset
);
171 /* Pick some ridiculous upper limit. Is 8 million CPUs enough? */
172 while (ret
== EINVAL
&& size
< 1024 * 1024);
176 iattr
->cpuset
= cpuset
;
177 iattr
->cpusetsize
= size
;
184 /* There is no such functionality. */
186 iattr
->cpuset
= NULL
;
187 iattr
->cpusetsize
= 0;
192 lll_unlock (thread
->lock
, LLL_PRIVATE
);