6a51defa03
This is needed to fix gdbserver's handling of threaded programs, among other things. Change-Id: I823387c602cef9891532da946a01db14be780ab0
139 lines
5.1 KiB
C
139 lines
5.1 KiB
C
/*
|
|
* Copyright (C) 2008 The Android Open Source Project
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* * Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* * Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in
|
|
* the documentation and/or other materials provided with the
|
|
* distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
|
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
|
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
|
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
|
|
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
|
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
|
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
|
|
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
#ifndef _SYS_TLS_H
|
|
#define _SYS_TLS_H
|
|
|
|
#include <sys/cdefs.h>
|
|
|
|
__BEGIN_DECLS
|
|
|
|
/** WARNING WARNING WARNING
|
|
**
|
|
** This header file is *NOT* part of the public Bionic ABI/API
|
|
** and should not be used/included by user-serviceable parts of
|
|
** the system (e.g. applications).
|
|
**
|
|
** It is only provided here for the benefit of the system dynamic
|
|
** linker and the OpenGL sub-system (which needs to access the
|
|
** pre-allocated slot directly for performance reason).
|
|
**/
|
|
|
|
/* maximum number of elements in the TLS array */
|
|
#define BIONIC_TLS_SLOTS 64
|
|
|
|
/* note that slot 0, called TLS_SLOT_SELF must point to itself.
|
|
* this is required to implement thread-local storage with the x86
|
|
* Linux kernel, that reads the TLS from fs:[0], where 'fs' is a
|
|
* thread-specific segment descriptor...
|
|
*/
|
|
|
|
/* Well known TLS slots */
|
|
#define TLS_SLOT_SELF 0
|
|
#define TLS_SLOT_THREAD_ID 1
|
|
#define TLS_SLOT_ERRNO 2
|
|
|
|
#define TLS_SLOT_OPENGL_API 3
|
|
#define TLS_SLOT_OPENGL 4
|
|
|
|
/* this slot is only used to pass information from the dynamic linker to
|
|
* libc.so when the C library is loaded in to memory. The C runtime init
|
|
* function will then clear it. Since its use is extremely temporary,
|
|
* we reuse an existing location.
|
|
*/
|
|
#define TLS_SLOT_BIONIC_PREINIT (TLS_SLOT_ERRNO+1)
|
|
|
|
/* small technical note: it is not possible to call pthread_setspecific
|
|
* on keys that are <= TLS_SLOT_MAX_WELL_KNOWN, which is why it is set to
|
|
* TLS_SLOT_ERRNO.
|
|
*
|
|
* later slots like TLS_SLOT_OPENGL are pre-allocated through the use of
|
|
* TLS_DEFAULT_ALLOC_MAP. this means that there is no need to use
|
|
* pthread_key_create() to initialize them. on the other hand, there is
|
|
* no destructor associated to them (we might need to implement this later)
|
|
*/
|
|
#define TLS_SLOT_MAX_WELL_KNOWN TLS_SLOT_ERRNO
|
|
|
|
#define TLS_DEFAULT_ALLOC_MAP 0x0000001F
|
|
|
|
/* set the Thread Local Storage, must contain at least BIONIC_TLS_SLOTS pointers */
|
|
extern void __init_tls(void** tls, void* thread_info);
|
|
|
|
/* syscall only, do not call directly */
|
|
extern int __set_tls(void *ptr);
|
|
|
|
/* get the TLS */
|
|
#ifdef __arm__
|
|
/* The standard way to get the TLS is to call a kernel helper
|
|
* function (i.e. a function provided at a fixed address in a
|
|
* "magic page" mapped in all user-space address spaces ), which
|
|
* contains the most appropriate code path for the target device.
|
|
*
|
|
* However, for performance reasons, we're going to use our own
|
|
* machine code for the system's C shared library.
|
|
*
|
|
* We cannot use this optimization in the static version of the
|
|
* C library, because we don't know where the corresponding code
|
|
* is going to run.
|
|
*/
|
|
# ifdef LIBC_STATIC
|
|
|
|
/* Use the kernel helper in static C library. */
|
|
typedef volatile void* (__kernel_get_tls_t)(void);
|
|
# define __get_tls() (*(__kernel_get_tls_t *)0xffff0fe0)()
|
|
|
|
# else /* !LIBC_STATIC */
|
|
/* Use optimized code path.
|
|
* Note that HAVE_ARM_TLS_REGISTER is build-specific
|
|
* (it must match your kernel configuration)
|
|
*/
|
|
# ifdef HAVE_ARM_TLS_REGISTER
|
|
/* We can read the address directly from a coprocessor
|
|
* register, which avoids touching the data cache
|
|
* completely.
|
|
*/
|
|
# define __get_tls() \
|
|
({ register unsigned int __val asm("r0"); \
|
|
asm ("mrc p15, 0, r0, c13, c0, 3" : "=r"(__val) ); \
|
|
(volatile void*)__val; })
|
|
# else /* !HAVE_ARM_TLS_REGISTER */
|
|
/* The kernel provides the address of the TLS at a fixed
|
|
* address of the magic page too.
|
|
*/
|
|
# define __get_tls() ( *((volatile void **) 0xffff0ff0) )
|
|
# endif
|
|
# endif /* !LIBC_STATIC */
|
|
#else /* !ARM */
|
|
extern void* __get_tls( void );
|
|
#endif /* !ARM */
|
|
|
|
/* return the stack base and size, used by our malloc debugger */
|
|
extern void* __get_stack_base(int *p_stack_size);
|
|
|
|
__END_DECLS
|
|
|
|
#endif /* _SYS_TLS_H */
|