about summary refs log tree commit diff
path: root/sysdeps/m68k/nptl/tls.h
blob: cfcd6d2b7b59321ca0528872079dc9230251db93 (plain) (blame)
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
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
/* Definition for thread-local data handling.  NPTL/m68k version.
   Copyright (C) 2010-2021 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Maxim Kuvyrkov <maxim@codesourcery.com>, 2010.

   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/>.  */

#ifndef _TLS_H
#define _TLS_H	1

#include <dl-sysdep.h>

#ifndef __ASSEMBLER__
# include <stdbool.h>
# include <stddef.h>
# include <stdint.h>
# include <dl-dtv.h>

#else /* __ASSEMBLER__ */
# include <tcb-offsets.h>
#endif /* __ASSEMBLER__ */

#ifndef __ASSEMBLER__

/* Get system call information.  */
# include <sysdep.h>

/* The TP points to the start of the thread blocks.  */
# define TLS_DTV_AT_TP	1
# define TLS_TCB_AT_TP	0

/* Get the thread descriptor definition.  */
# include <nptl/descr.h>

typedef struct
{
  dtv_t *dtv;
  void *private;
} tcbhead_t;

/* This is the size of the initial TCB.  Because our TCB is before the thread
   pointer, we don't need this.  */
# define TLS_INIT_TCB_SIZE	0

/* Alignment requirements for the initial TCB.  */
# define TLS_INIT_TCB_ALIGN	__alignof__ (struct pthread)

/* This is the size of the TCB.  Because our TCB is before the thread
   pointer, we don't need this.  */
# define TLS_TCB_SIZE		0

/* Alignment requirements for the TCB.  */
# define TLS_TCB_ALIGN		__alignof__ (struct pthread)

/* This is the size we need before TCB - actually, it includes the TCB.  */
# define TLS_PRE_TCB_SIZE						\
  (sizeof (struct pthread)						\
   + ((sizeof (tcbhead_t) + TLS_TCB_ALIGN - 1) & ~(TLS_TCB_ALIGN - 1)))

/* The thread pointer (TP) points to the end of the
   TCB + 0x7000, as for PowerPC and MIPS.  This implies that TCB address is
   TP - 0x7000.  As we define TLS_DTV_AT_TP we can
   assume that the pthread struct is allocated immediately ahead of the
   TCB.  This implies that the pthread_descr address is
   TP - (TLS_PRE_TCB_SIZE + 0x7000).  */
# define TLS_TCB_OFFSET	0x7000

/* Install the dtv pointer.  The pointer passed is to the element with
   index -1 which contain the length.  */
# define INSTALL_DTV(tcbp, dtvp) \
  ((tcbhead_t *) (tcbp))[-1].dtv = dtvp + 1

/* Install new dtv for current thread.  */
# define INSTALL_NEW_DTV(dtv) \
  (THREAD_DTV () = (dtv))

/* Return dtv of given thread descriptor.  */
# define GET_DTV(tcbp) \
  (((tcbhead_t *) (tcbp))[-1].dtv)

/* Code to initially initialize the thread pointer.  This might need
   special attention since 'errno' is not yet available and if the
   operation can cause a failure 'errno' must not be touched.  */
# define TLS_INIT_TP(tcbp)						\
  ({									\
    int _sys_result;							\
									\
    _sys_result = INTERNAL_SYSCALL_CALL (set_thread_area, 		\
				    ((void *) (tcbp)) + TLS_TCB_OFFSET); \
    INTERNAL_SYSCALL_ERROR_P (_sys_result) ? "unknown error" : NULL; })

# define TLS_DEFINE_INIT_TP(tp, pd) \
  void *tp = (void *) (pd) + TLS_TCB_OFFSET + TLS_PRE_TCB_SIZE

extern void * __m68k_read_tp (void);

/* Return the address of the dtv for the current thread.  */
# define THREAD_DTV() \
  (((tcbhead_t *) (__m68k_read_tp () - TLS_TCB_OFFSET))[-1].dtv)

/* Return the thread descriptor for the current thread.  */
# define THREAD_SELF \
  ((struct pthread *) (__m68k_read_tp () - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE))

/* Magic for libthread_db to know how to do THREAD_SELF.  */
# define DB_THREAD_SELF \
  CONST_THREAD_AREA (32, TLS_TCB_OFFSET + TLS_PRE_TCB_SIZE)

/* Access to data in the thread descriptor is easy.  */
# define THREAD_GETMEM(descr, member) \
  descr->member
# define THREAD_GETMEM_NC(descr, member, idx) \
  descr->member[idx]
# define THREAD_SETMEM(descr, member, value) \
  descr->member = (value)
# define THREAD_SETMEM_NC(descr, member, idx, value) \
  descr->member[idx] = (value)

/* l_tls_offset == 0 is perfectly valid on M68K, so we have to use some
   different value to mean unset l_tls_offset.  */
# define NO_TLS_OFFSET		-1

/* Get and set the global scope generation counter in struct pthread.  */
#define THREAD_GSCOPE_IN_TCB      1
#define THREAD_GSCOPE_FLAG_UNUSED 0
#define THREAD_GSCOPE_FLAG_USED   1
#define THREAD_GSCOPE_FLAG_WAIT   2
#define THREAD_GSCOPE_RESET_FLAG()					\
  do									\
    { int __res								\
	= atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,	\
			       THREAD_GSCOPE_FLAG_UNUSED);		\
      if (__res == THREAD_GSCOPE_FLAG_WAIT)				\
	lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE); \
    }									\
  while (0)
#define THREAD_GSCOPE_SET_FLAG()					\
  do									\
    {									\
      THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;	\
      atomic_write_barrier ();						\
    }									\
  while (0)

#endif /* __ASSEMBLER__ */

#endif	/* tls.h */