1 /* Stack cache management for NPTL.
2    Copyright (C) 2002-2022 Free Software Foundation, Inc.
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
7    License as published by the Free Software Foundation; either
8    version 2.1 of the 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
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #ifndef _NPTL_STACK_H
20 #define _NPTL_STACK_H
21 
22 #include <nptl/descr.h>
23 #include <ldsodefs.h>
24 #include <list.h>
25 #include <stdbool.h>
26 
27 /* Maximum size of the cache, in bytes.  40 MiB by default.  */
28 extern size_t __nptl_stack_cache_maxsize attribute_hidden;
29 
30 /* Check whether the stack is still used or not.  */
31 static inline bool
__nptl_stack_in_use(struct pthread * pd)32 __nptl_stack_in_use (struct pthread *pd)
33 {
34   return pd->tid <= 0;
35 }
36 
37 /* Remove the stack ELEM from its list.  */
38 void __nptl_stack_list_del (list_t *elem);
39 libc_hidden_proto (__nptl_stack_list_del)
40 
41 /* Add ELEM to a stack list.  LIST can be either &GL (dl_stack_used)
42    or &GL (dl_stack_cache).  */
43 void __nptl_stack_list_add (list_t *elem, list_t *list);
44 libc_hidden_proto (__nptl_stack_list_add)
45 
46 /* Free allocated stack.  */
47 extern void __nptl_deallocate_stack (struct pthread *pd);
48 libc_hidden_proto (__nptl_deallocate_stack)
49 
50 /* Free stacks until cache size is lower than LIMIT.  */
51 void __nptl_free_stacks (size_t limit) attribute_hidden;
52 
53 /* Compute the size of the static TLS area based on data from the
54    dynamic loader.  */
55 static inline size_t
__nptl_tls_static_size_for_stack(void)56 __nptl_tls_static_size_for_stack (void)
57 {
58   return roundup (GLRO (dl_tls_static_size), GLRO (dl_tls_static_align));
59 }
60 
61 #endif /* _NPTL_STACK_H */
62