bionic/libc/private/bionic_tls.h
Dan Albert aa23b2ee5e Add a TLS slot for TSAN.
This is so TSAN won't need to rely on pthread_getspecific for finding
the current thread state.

Change-Id: Id3befeabec0a9f7ca77b5549fbc427e22e6aaa34
2015-08-18 15:09:00 -07:00

128 lines
4.7 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 __BIONIC_PRIVATE_BIONIC_TLS_H_
#define __BIONIC_PRIVATE_BIONIC_TLS_H_
#include <sys/cdefs.h>
#include <sys/limits.h>
#include "bionic_macros.h"
#include "__get_tls.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).
**/
// Well-known TLS slots. What data goes in which slot is arbitrary unless otherwise noted.
enum {
TLS_SLOT_SELF = 0, // The kernel requires this specific slot for x86.
TLS_SLOT_THREAD_ID,
TLS_SLOT_ERRNO,
// These two aren't used by bionic itself, but allow the graphics code to
// access TLS directly rather than using the pthread API.
TLS_SLOT_OPENGL_API = 3,
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 that isn't needed during libc startup.
TLS_SLOT_BIONIC_PREINIT = TLS_SLOT_OPENGL_API,
TLS_SLOT_STACK_GUARD = 5, // GCC requires this specific slot for x86.
TLS_SLOT_DLERROR,
// Fast storage for Thread::Current() in ART.
TLS_SLOT_ART_THREAD_SELF,
// Lets TSAN avoid using pthread_getspecific for finding the current thread
// state.
TLS_SLOT_TSAN,
BIONIC_TLS_SLOTS // Must come last!
};
/*
* Bionic uses some pthread keys internally. All pthread keys used internally
* should be created in constructors, except for keys that may be used in or
* before constructors.
*
* We need to manually maintain the count of pthread keys used internally, but
* pthread_test should fail if we forget.
*
* These are the pthread keys currently used internally by libc:
*
* basename libc (ThreadLocalBuffer)
* dirname libc (ThreadLocalBuffer)
* uselocale libc (can be used in constructors)
* getmntent_mntent libc (ThreadLocalBuffer)
* getmntent_strings libc (ThreadLocalBuffer)
* ptsname libc (ThreadLocalBuffer)
* ttyname libc (ThreadLocalBuffer)
* strerror libc (ThreadLocalBuffer)
* strsignal libc (ThreadLocalBuffer)
* passwd libc (ThreadLocalBuffer)
* group libc (ThreadLocalBuffer)
* _res_key libc (constructor in BSD code)
*/
#define LIBC_PTHREAD_KEY_RESERVED_COUNT 12
#if defined(USE_JEMALLOC)
/* Internally, jemalloc uses a single key for per thread data. */
#define JEMALLOC_PTHREAD_KEY_RESERVED_COUNT 1
#define BIONIC_PTHREAD_KEY_RESERVED_COUNT (LIBC_PTHREAD_KEY_RESERVED_COUNT + JEMALLOC_PTHREAD_KEY_RESERVED_COUNT)
#else
#define BIONIC_PTHREAD_KEY_RESERVED_COUNT LIBC_PTHREAD_KEY_RESERVED_COUNT
#endif
/*
* Maximum number of pthread keys allocated.
* This includes pthread keys used internally and externally.
*/
#define BIONIC_PTHREAD_KEY_COUNT (BIONIC_PTHREAD_KEY_RESERVED_COUNT + PTHREAD_KEYS_MAX)
__END_DECLS
#if defined(__cplusplus)
class KernelArgumentBlock;
extern __LIBC_HIDDEN__ void __libc_init_main_thread(KernelArgumentBlock& args);
#endif
#endif /* __BIONIC_PRIVATE_BIONIC_TLS_H_ */