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Diffstat (limited to 'libpthread/nptl/sysdeps/riscv32/tls.h')
| -rw-r--r-- | libpthread/nptl/sysdeps/riscv32/tls.h | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/libpthread/nptl/sysdeps/riscv32/tls.h b/libpthread/nptl/sysdeps/riscv32/tls.h new file mode 100644 index 000000000..ed6df8186 --- /dev/null +++ b/libpthread/nptl/sysdeps/riscv32/tls.h @@ -0,0 +1,201 @@ +/* Definition for thread-local data handling. NPTL/RISCV32 version. + Copyright (C) 2005, 2007, 2011 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 + +#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; + +typedef struct +{ + dtv_t *dtv; +} tcbhead_t; + +register tcbhead_t *__thread_self __asm__("tp"); + +# define TLS_MULTIPLE_THREADS_IN_TCB 1 + +#else /* __ASSEMBLER__ */ +# include <tcb-offsets.h> +#endif /* __ASSEMBLER__ */ + +/* We require TLS support in the tools. */ +#define HAVE_TLS_SUPPORT 1 +#define HAVE_TLS_MODEL_ATTRIBUTE 1 +#define HAVE___THREAD 1 + +/* Signal that TLS support is available. */ +#define USE_TLS 1 + +#ifndef __ASSEMBLER__ + +/* Get system call information. */ +# include <sysdep.h> + +/* The TP points to the start of the TLS block. + * As I understand it, this isn't strictly that "TP points to DTV" - it's + * more where to place the TCB in the TLS block. This will place it in + * the beginning. + * + * Layout: + * ------------------------------------ + * | PRE | TCB | TLS MEMORY .. | + * ------------------------------------ + * ^ x4 / TP + * + * PRE is the struct pthread described below + * TCB is tcbhead_t + * TLS memory is where the TLS program sections are loaded + * + * See _dl_allocate_tls_storage and __libc_setup_tls for more information. + */ +# define TLS_DTV_AT_TP 1 + +/* Get the thread descriptor definition. */ +# include <../../descr.h> + +/* Requirements for the TCB. */ +# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t) +# define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t) + +# define TLS_TCB_SIZE sizeof (tcbhead_t) +# define TLS_TCB_ALIGN __alignof__ (tcbhead_t) + +/* This is the size of the TCB. */ + +/* This is the size we need before TCB. + * To support THREAD_GETMEM with friends we want to have a + * struct pthread available. + * Yank it in infront of everything, I'm sure nobody will mind. + * + * This memory is really allocated PRE the TLS block, so it's possible + * to do ((char*)tlsblock) - TLS_PRE_TCB_SIZE to access it. + * This is done for THREAD_SELF. */ +# define TLS_PRE_TCB_SIZE sizeof (struct pthread) + + +/* Install the dtv pointer. + * When called, dtvp is a pointer not the DTV per say (which should start + * with the generation counter) but to the length of the DTV. + * We can always index with -1, so we store dtvp[1] + */ +# define INSTALL_DTV(tcbp, dtvp) \ + (((tcbhead_t *) (tcbp))->dtv = (dtvp) + 1) + +/* Install new dtv for current thread + * In a logicial world dtv here would also point to the length of the DTV. + * However it does not, this time it points to the generation counter, + * so just store it. + * + * Note: -1 is still valid and contains the length. */ +# define INSTALL_NEW_DTV(dtv) \ + (THREAD_DTV() = (dtv)) + +/* Return dtv of given thread descriptor. */ +# define GET_DTV(tcbp) \ + (((tcbhead_t *) (tcbp))->dtv) + +/* Code to initially initialize the thread pointer. + * + * Set TP to the address _after_ tcbhead_t. This will allow us + * to change the size of tcbhead_t without having to re-link everything. + * + * secondcall has something to do with USE__THREAD, + * seems to always be 0 so we don't care about it. + * + * This has to return NULL on success (or a string with the failure text). + * It's hard to fail this, so return NULL always. + */ +# define TLS_INIT_TP(tcbp, secondcall) \ + ({__thread_self = ((tcbhead_t *)tcbp + 1); NULL;}) + +/* Return the address of the dtv for the current thread. + * + * Dereference TP, offset to dtv - really straightforward. + * Remember that we made TP point to after tcb, so we need to reverse that. + */ +# define THREAD_DTV() \ + ((((tcbhead_t *)__thread_self)-1)->dtv) + +/* Return the thread descriptor for the current thread. + * + * Return a pointer to the TLS_PRE area where we allocated space for + * a struct pthread. Again, TP points to after tcbhead_t, compensate with + * TLS_INIT_TCB_SIZE. + * + * I regard this is a seperate system from the "normal" TLS. + */ +# define THREAD_SELF \ + ((struct pthread *) ((char *) __thread_self - TLS_INIT_TCB_SIZE \ + - TLS_PRE_TCB_SIZE)) + +/* Magic for libthread_db to know how to do THREAD_SELF. */ +# define DB_THREAD_SELF \ + CONST_THREAD_AREA (64, sizeof (struct pthread)) + +/* 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) + +/* 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 */ + |