sysdeps/powerpc/nptl/tls.h

   1 /* Definition for thread-local data handling.  NPTL/PowerPC version.
   2    Copyright (C) 2003-2015 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _TLS_H
  20 #define _TLS_H  1
  21
  22 # include <dl-sysdep.h>
  23
  24 #ifndef __ASSEMBLER__
  25 # include <stdbool.h>
  26 # include <stddef.h>
  27 # include <stdint.h>
  28
  29 /* Type for the dtv.  */
  30 typedef union dtv
  31 {
  32   size_t counter;
  33   struct
  34   {
  35     void *val;
  36     bool is_static;
  37   } pointer;
  38 } dtv_t;
  39
  40 #else /* __ASSEMBLER__ */
  41 # include <tcb-offsets.h>
  42 #endif /* __ASSEMBLER__ */
  43
  44
  45 #ifndef __ASSEMBLER__
  46
  47 # include <hwcapinfo.h>
  48
  49 /* Get system call information.  */
  50 # include <sysdep.h>
  51
  52 /* The TP points to the start of the thread blocks.  */
  53 # define TLS_DTV_AT_TP  1
  54 # define TLS_TCB_AT_TP  0
  55
  56 /* We use the multiple_threads field in the pthread struct */
  57 #define TLS_MULTIPLE_THREADS_IN_TCB     1
  58
  59 /* Get the thread descriptor definition.  */
  60 # include <nptl/descr.h>
  61
  62
  63 /* The stack_guard is accessed directly by GCC -fstack-protector code,
  64    so it is a part of public ABI.  The dtv and pointer_guard fields
  65    are private.  */
  66 typedef struct
  67 {
  68   /* Reservation for HWCAP data.  To be accessed by GCC in
  69      __builtin_cpu_supports(), so it is a part of public ABI.  */
  70   uint64_t hwcap;
  71   /* Reservation for AT_PLATFORM data.  To be accessed by GCC in
  72      __builtin_cpu_is(), so it is a part of public ABI.  Since there
  73      are different ABIs for 32 and 64 bit, we put this field in a
  74      previously empty padding space for powerpc64.  */
  75 #ifndef __powerpc64__
  76   /* Padding to maintain alignment.  */
  77   uint32_t padding;
  78   uint32_t at_platform;
  79 #endif
  80   /* Indicate if HTM capable (ISA 2.07).  */
  81   uint32_t tm_capable;
  82   /* Reservation for AT_PLATFORM data - powerpc64.  */
  83 #ifdef __powerpc64__
  84   uint32_t at_platform;
  85 #endif
  86   /* Reservation for Dynamic System Optimizer ABI.  */
  87   uintptr_t dso_slot2;
  88   uintptr_t dso_slot1;
  89   /* Reservation for tar register (ISA 2.07).  */
  90   uintptr_t tar_save;
  91   /* GCC split stack support.  */
  92   void *__private_ss;
  93   /* Reservation for the Event-Based Branching ABI.  */
  94   uintptr_t ebb_handler;
  95   uintptr_t ebb_ctx_pointer;
  96   uintptr_t ebb_reserved1;
  97   uintptr_t ebb_reserved2;
  98   uintptr_t pointer_guard;
  99   uintptr_t stack_guard;
 100   dtv_t *dtv;
 101 } tcbhead_t;
 102
 103 /* This is the size of the initial TCB.  */
 104 # define TLS_INIT_TCB_SIZE      0
 105
 106 /* Alignment requirements for the initial TCB.  */
 107 # define TLS_INIT_TCB_ALIGN     __alignof__ (struct pthread)
 108
 109 /* This is the size of the TCB.  */
 110 # define TLS_TCB_SIZE           0
 111
 112 /* Alignment requirements for the TCB.  */
 113 # define TLS_TCB_ALIGN          __alignof__ (struct pthread)
 114
 115 /* This is the size we need before TCB.  */
 116 # define TLS_PRE_TCB_SIZE \
 117   (sizeof (struct pthread)                                                    \
 118    + ((sizeof (tcbhead_t) + TLS_TCB_ALIGN - 1) & ~(TLS_TCB_ALIGN - 1)))
 119
 120 # ifndef __powerpc64__
 121 /* Register r2 (tp) is reserved by the ABI as "thread pointer". */
 122 register void *__thread_register __asm__ ("r2");
 123 #  define PT_THREAD_POINTER PT_R2
 124 # else
 125 /* Register r13 (tp) is reserved by the ABI as "thread pointer". */
 126 register void *__thread_register __asm__ ("r13");
 127 #  define PT_THREAD_POINTER PT_R13
 128 # endif
 129
 130 /* The following assumes that TP (R2 or R13) points to the end of the
 131    TCB + 0x7000 (per the ABI).  This implies that TCB address is
 132    TP - 0x7000.  As we define TLS_DTV_AT_TP we can
 133    assume that the pthread struct is allocated immediately ahead of the
 134    TCB.  This implies that the pthread_descr address is
 135    TP - (TLS_PRE_TCB_SIZE + 0x7000).  */
 136 # define TLS_TCB_OFFSET 0x7000
 137
 138 /* Install the dtv pointer.  The pointer passed is to the element with
 139    index -1 which contain the length.  */
 140 # define INSTALL_DTV(tcbp, dtvp) \
 141   ((tcbhead_t *) (tcbp))[-1].dtv = dtvp + 1
 142
 143 /* Install new dtv for current thread.  */
 144 # define INSTALL_NEW_DTV(dtv) (THREAD_DTV() = (dtv))
 145
 146 /* Return dtv of given thread descriptor.  */
 147 # define GET_DTV(tcbp)  (((tcbhead_t *) (tcbp))[-1].dtv)
 148
 149 /* Code to initially initialize the thread pointer.  This might need
 150    special attention since 'errno' is not yet available and if the
 151    operation can cause a failure 'errno' must not be touched.  */
 152 # define TLS_INIT_TP(tcbp) \
 153   ({                                                                          \
 154     __thread_register = (void *) (tcbp) + TLS_TCB_OFFSET;                     \
 155     THREAD_SET_TM_CAPABLE (__tcb_hwcap & PPC_FEATURE2_HAS_HTM ? 1 : 0);       \
 156     THREAD_SET_HWCAP (__tcb_hwcap);                                           \
 157     THREAD_SET_AT_PLATFORM (__tcb_platform);                                  \
 158     NULL;                                                                     \
 159   })
 160
 161 /* Value passed to 'clone' for initialization of the thread register.  */
 162 # define TLS_DEFINE_INIT_TP(tp, pd) \
 163     void *tp = (void *) (pd) + TLS_TCB_OFFSET + TLS_PRE_TCB_SIZE;             \
 164     (((tcbhead_t *) ((char *) tp - TLS_TCB_OFFSET))[-1].tm_capable) =         \
 165       THREAD_GET_TM_CAPABLE ();                                               \
 166     (((tcbhead_t *) ((char *) tp - TLS_TCB_OFFSET))[-1].hwcap) =              \
 167       THREAD_GET_HWCAP ();                                                    \
 168     (((tcbhead_t *) ((char *) tp - TLS_TCB_OFFSET))[-1].at_platform) =        \
 169       THREAD_GET_AT_PLATFORM ();
 170
 171 /* Return the address of the dtv for the current thread.  */
 172 # define THREAD_DTV() \
 173     (((tcbhead_t *) (__thread_register - TLS_TCB_OFFSET))[-1].dtv)
 174
 175 /* Return the thread descriptor for the current thread.  */
 176 # define THREAD_SELF \
 177     ((struct pthread *) (__thread_register \
 178                          - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE))
 179
 180 /* Magic for libthread_db to know how to do THREAD_SELF.  */
 181 # define DB_THREAD_SELF                                                       \
 182   REGISTER (32, 32, PT_THREAD_POINTER * 4,                                    \
 183             - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE)                              \
 184   REGISTER (64, 64, PT_THREAD_POINTER * 8,                                    \
 185             - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE)
 186
 187 /* Read member of the thread descriptor directly.  */
 188 # define THREAD_GETMEM(descr, member) ((void)(descr), (THREAD_SELF)->member)
 189
 190 /* Same as THREAD_GETMEM, but the member offset can be non-constant.  */
 191 # define THREAD_GETMEM_NC(descr, member, idx) \
 192     ((void)(descr), (THREAD_SELF)->member[idx])
 193
 194 /* Set member of the thread descriptor directly.  */
 195 # define THREAD_SETMEM(descr, member, value) \
 196     ((void)(descr), (THREAD_SELF)->member = (value))
 197
 198 /* Same as THREAD_SETMEM, but the member offset can be non-constant.  */
 199 # define THREAD_SETMEM_NC(descr, member, idx, value) \
 200     ((void)(descr), (THREAD_SELF)->member[idx] = (value))
 201
 202 /* Set the stack guard field in TCB head.  */
 203 # define THREAD_SET_STACK_GUARD(value) \
 204     (((tcbhead_t *) ((char *) __thread_register                               \
 205                      - TLS_TCB_OFFSET))[-1].stack_guard = (value))
 206 # define THREAD_COPY_STACK_GUARD(descr) \
 207     (((tcbhead_t *) ((char *) (descr)                                         \
 208                      + TLS_PRE_TCB_SIZE))[-1].stack_guard                     \
 209      = ((tcbhead_t *) ((char *) __thread_register                             \
 210                        - TLS_TCB_OFFSET))[-1].stack_guard)
 211
 212 /* Set the stack guard field in TCB head.  */
 213 # define THREAD_GET_POINTER_GUARD() \
 214     (((tcbhead_t *) ((char *) __thread_register                               \
 215                      - TLS_TCB_OFFSET))[-1].pointer_guard)
 216 # define THREAD_SET_POINTER_GUARD(value) \
 217     (THREAD_GET_POINTER_GUARD () = (value))
 218 # define THREAD_COPY_POINTER_GUARD(descr) \
 219     (((tcbhead_t *) ((char *) (descr)                                         \
 220                      + TLS_PRE_TCB_SIZE))[-1].pointer_guard                   \
 221      = THREAD_GET_POINTER_GUARD())
 222
 223 /* tm_capable field in TCB head.  */
 224 # define THREAD_GET_TM_CAPABLE() \
 225     (((tcbhead_t *) ((char *) __thread_register                               \
 226                      - TLS_TCB_OFFSET))[-1].tm_capable)
 227 # define THREAD_SET_TM_CAPABLE(value) \
 228     (THREAD_GET_TM_CAPABLE () = (value))
 229
 230 /* hwcap field in TCB head.  */
 231 # define THREAD_GET_HWCAP() \
 232     (((tcbhead_t *) ((char *) __thread_register                               \
 233                      - TLS_TCB_OFFSET))[-1].hwcap)
 234 # define THREAD_SET_HWCAP(value) \
 235     (THREAD_GET_HWCAP () = (value))
 236
 237 /* at_platform field in TCB head.  */
 238 # define THREAD_GET_AT_PLATFORM() \
 239     (((tcbhead_t *) ((char *) __thread_register                               \
 240                      - TLS_TCB_OFFSET))[-1].at_platform)
 241 # define THREAD_SET_AT_PLATFORM(value) \
 242     (THREAD_GET_AT_PLATFORM () = (value))
 243
 244 /* l_tls_offset == 0 is perfectly valid on PPC, so we have to use some
 245    different value to mean unset l_tls_offset.  */
 246 # define NO_TLS_OFFSET          -1
 247
 248 /* Get and set the global scope generation counter in struct pthread.  */
 249 #define THREAD_GSCOPE_FLAG_UNUSED 0
 250 #define THREAD_GSCOPE_FLAG_USED   1
 251 #define THREAD_GSCOPE_FLAG_WAIT   2
 252 #define THREAD_GSCOPE_RESET_FLAG() \
 253   do                                                                         \
 254     { int __res                                                              \
 255         = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,             \
 256                                THREAD_GSCOPE_FLAG_UNUSED);                   \
 257       if (__res == THREAD_GSCOPE_FLAG_WAIT)                                  \
 258         lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE);   \
 259     }                                                                        \
 260   while (0)
 261 #define THREAD_GSCOPE_SET_FLAG() \
 262   do                                                                         \
 263     {                                                                        \
 264       THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;             \
 265       atomic_write_barrier ();                                               \
 266     }                                                                        \
 267   while (0)
 268 #define THREAD_GSCOPE_WAIT() \
 269   GL(dl_wait_lookup_done) ()
 270
 271 #endif /* __ASSEMBLER__ */
 272
 273 #endif  /* tls.h */