glibc/sysdeps/mips/nptl/tls.h
2012-03-09 23:56:38 +00:00

176 lines
5.5 KiB
C

/* Definition for thread-local data handling. NPTL/MIPS version.
Copyright (C) 2005, 2007 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
<http://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>
/* Type for the dtv. */
typedef union dtv
{
size_t counter;
struct
{
void *val;
bool is_static;
} pointer;
} dtv_t;
/* Note: rd must be $v1 to be ABI-conformant. */
# define READ_THREAD_POINTER() \
({ void *__result; \
asm volatile (".set\tpush\n\t.set\tmips32r2\n\t" \
"rdhwr\t%0, $29\n\t.set\tpop" : "=v" (__result)); \
__result; })
#else /* __ASSEMBLER__ */
# include <tcb-offsets.h>
# define READ_THREAD_POINTER(rd) \
.set push; \
.set mips32r2; \
rdhwr rd, $29; \
.set pop
#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
/* 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 (in hardware register $29) points to the end of
the TCB + 0x7000, as for PowerPC. The pthread_descr structure is
immediately in front of the TCB. */
# 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, secondcall) \
({ INTERNAL_SYSCALL_DECL (err); \
long result_var; \
result_var = INTERNAL_SYSCALL (set_thread_area, err, 1, \
(char *) (tcbp) + TLS_TCB_OFFSET); \
INTERNAL_SYSCALL_ERROR_P (result_var, err) \
? "unknown error" : NULL; })
/* Return the address of the dtv for the current thread. */
# define THREAD_DTV() \
(((tcbhead_t *) (READ_THREAD_POINTER () - TLS_TCB_OFFSET))[-1].dtv)
/* Return the thread descriptor for the current thread. */
# define THREAD_SELF \
((struct pthread *) (READ_THREAD_POINTER () \
- 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 MIPS, 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_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)
#define THREAD_GSCOPE_WAIT() \
GL(dl_wait_lookup_done) ()
#endif /* __ASSEMBLER__ */
#endif /* tls.h */