1 /* Definition for thread-local data handling.  NPTL/ARC version.
2    Copyright (C) 2020-2022 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 _ARC_NPTL_TLS_H
20 #define _ARC_NPTL_TLS_H	1
21 
22 #include <dl-sysdep.h>
23 
24 #ifndef __ASSEMBLER__
25 
26 # include <stdbool.h>
27 # include <stddef.h>
28 # include <stdint.h>
29 
30 #include <dl-dtv.h>
31 
32 /* Get system call information.  */
33 # include <sysdep.h>
34 
35 /* The TLS blocks start right after the TCB.  */
36 # define TLS_DTV_AT_TP	1
37 # define TLS_TCB_AT_TP	0
38 
39 /* Get the thread descriptor definition.  */
40 # include <nptl/descr.h>
41 
42 typedef struct
43 {
44   dtv_t *dtv;
45   uintptr_t pointer_guard;
46 } tcbhead_t;
47 
48 /* This is the size of the initial TCB.  */
49 # define TLS_INIT_TCB_SIZE	sizeof (tcbhead_t)
50 
51 /* This is the size of the TCB.  */
52 #ifndef TLS_TCB_SIZE
53 # define TLS_TCB_SIZE		sizeof (tcbhead_t)
54 #endif
55 
56 /* This is the size we need before TCB.  */
57 # define TLS_PRE_TCB_SIZE	sizeof (struct pthread)
58 
59 /* Install the dtv pointer.  The pointer passed is to the element with
60    index -1 which contain the length.  */
61 # define INSTALL_DTV(tcbp, dtvp) \
62   (((tcbhead_t *) (tcbp))->dtv = (dtvp) + 1)
63 
64 /* Install new dtv for current thread.  */
65 # define INSTALL_NEW_DTV(dtv) \
66   (THREAD_DTV() = (dtv))
67 
68 /* Return dtv of given thread descriptor.  */
69 # define GET_DTV(tcbp) \
70   (((tcbhead_t *) (tcbp))->dtv)
71 
72 /* Code to initially initialize the thread pointer.  */
73 # define TLS_INIT_TP(tcbp)					\
74   ({                                            		\
75 	long result_var;					\
76 	__builtin_set_thread_pointer (tcbp);     		\
77 	result_var = INTERNAL_SYSCALL_CALL (arc_settls, (tcbp));\
78 	INTERNAL_SYSCALL_ERROR_P (result_var)			\
79 	  ? "settls syscall error" : NULL;			\
80    })
81 
82 /* Value passed to 'clone' for initialization of the thread register.  */
83 # define TLS_DEFINE_INIT_TP(tp, pd) void *tp = (pd) + 1
84 
85 /* Return the address of the dtv for the current thread.  */
86 # define THREAD_DTV() \
87   (((tcbhead_t *) __builtin_thread_pointer ())->dtv)
88 
89 /* Return the thread descriptor for the current thread.  */
90 # define THREAD_SELF \
91  ((struct pthread *)__builtin_thread_pointer () - 1)
92 
93 /* Magic for libthread_db to know how to do THREAD_SELF.  */
94 # define DB_THREAD_SELF \
95   CONST_THREAD_AREA (32, sizeof (struct pthread))
96 
97 # include <tcb-access.h>
98 
99 /* Get and set the global scope generation counter in struct pthread.  */
100 #define THREAD_GSCOPE_FLAG_UNUSED 0
101 #define THREAD_GSCOPE_FLAG_USED   1
102 #define THREAD_GSCOPE_FLAG_WAIT   2
103 #define THREAD_GSCOPE_RESET_FLAG() \
104   do									     \
105     { int __res								     \
106 	= atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,	     \
107 			       THREAD_GSCOPE_FLAG_UNUSED);		     \
108       if (__res == THREAD_GSCOPE_FLAG_WAIT)				     \
109 	lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE);   \
110     }									     \
111   while (0)
112 #define THREAD_GSCOPE_SET_FLAG() \
113   do									     \
114     {									     \
115       THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;	     \
116       atomic_write_barrier ();						     \
117     }									     \
118   while (0)
119 
120 #endif /* !__ASSEMBLER__ */
121 
122 #endif	/* tls.h */
123