glibc/sysdeps/m68k/nptl/tls.h

142 lines
4.6 KiB
C

/* Definition for thread-local data handling. NPTL/m68k version.
Copyright (C) 2010-2024 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/>. */
#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>
#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
/* 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
/* This is the size we need before TCB - actually, it includes the TCB. */
# define TLS_PRE_TCB_SIZE \
(sizeof (struct pthread) \
+ ((sizeof (tcbhead_t) + __alignof (struct pthread) - 1) \
& ~(__alignof (struct pthread) - 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); })
# 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)
# include <tcb-access.h>
/* 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_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_release (&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 */