sysdeps/powerpc/nptl/tls.h

   1 /* Definition for thread-local data handling.  NPTL/PowerPC version.
   2    Copyright (C) 2003-2018 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 # include <dl-dtv.h>
  29
  30 #else /* __ASSEMBLER__ */
  31 # include <tcb-offsets.h>
  32 #endif /* __ASSEMBLER__ */
  33
  34
  35 #ifndef __ASSEMBLER__
  36
  37 # include <hwcapinfo.h>
  38
  39 /* Get system call information.  */
  40 # include <sysdep.h>
  41
  42 /* The TP points to the start of the thread blocks.  */
  43 # define TLS_DTV_AT_TP  1
  44 # define TLS_TCB_AT_TP  0
  45
  46 /* We use the multiple_threads field in the pthread struct */
  47 #define TLS_MULTIPLE_THREADS_IN_TCB     1
  48
  49 /* Get the thread descriptor definition.  */
  50 # include <nptl/descr.h>
  51
  52
  53 /* The stack_guard is accessed directly by GCC -fstack-protector code,
  54    so it is a part of public ABI.  The dtv and pointer_guard fields
  55    are private.  */
  56 typedef struct
  57 {
  58   /* Reservation for HWCAP data.  To be accessed by GCC in
  59      __builtin_cpu_supports(), so it is a part of public ABI.  */
  60   uint64_t hwcap;
  61   /* Reservation for AT_PLATFORM data.  To be accessed by GCC in
  62      __builtin_cpu_is(), so it is a part of public ABI.  Since there
  63      are different ABIs for 32 and 64 bit, we put this field in a
  64      previously empty padding space for powerpc64.  */
  65 #ifndef __powerpc64__
  66   /* Padding to maintain alignment.  */
  67   uint32_t padding;
  68   uint32_t at_platform;
  69 #endif
  70   /* Indicate if HTM capable (ISA 2.07).  */
  71   uint32_t tm_capable;
  72   /* Reservation for AT_PLATFORM data - powerpc64.  */
  73 #ifdef __powerpc64__
  74   uint32_t at_platform;
  75 #endif
  76   /* Reservation for Dynamic System Optimizer ABI.  */
  77   uintptr_t dso_slot2;
  78   uintptr_t dso_slot1;
  79   /* Reservation for tar register (ISA 2.07).  */
  80   uintptr_t tar_save;
  81   /* GCC split stack support.  */
  82   void *__private_ss;
  83   /* Reservation for the Event-Based Branching ABI.  */
  84   uintptr_t ebb_handler;
  85   uintptr_t ebb_ctx_pointer;
  86   uintptr_t ebb_reserved1;
  87   uintptr_t ebb_reserved2;
  88   uintptr_t pointer_guard;
  89   uintptr_t stack_guard;
  90   dtv_t *dtv;
  91 } tcbhead_t;
  92
  93 /* This is the size of the initial TCB.  */
  94 # define TLS_INIT_TCB_SIZE      0
  95
  96 /* Alignment requirements for the initial TCB.  */
  97 # define TLS_INIT_TCB_ALIGN     __alignof__ (struct pthread)
  98
  99 /* This is the size of the TCB.  */
 100 # define TLS_TCB_SIZE           0
 101
 102 /* Alignment requirements for the TCB.  */
 103 # define TLS_TCB_ALIGN          __alignof__ (struct pthread)
 104
 105 /* This is the size we need before TCB.  */
 106 # define TLS_PRE_TCB_SIZE \
 107   (sizeof (struct pthread)                                                    \
 108    + ((sizeof (tcbhead_t) + TLS_TCB_ALIGN - 1) & ~(TLS_TCB_ALIGN - 1)))
 109
 110 # ifndef __powerpc64__
 111 /* Register r2 (tp) is reserved by the ABI as "thread pointer". */
 112 register void *__thread_register __asm__ ("r2");
 113 #  define PT_THREAD_POINTER PT_R2
 114 # else
 115 /* Register r13 (tp) is reserved by the ABI as "thread pointer". */
 116 register void *__thread_register __asm__ ("r13");
 117 #  define PT_THREAD_POINTER PT_R13
 118 # endif
 119
 120 /* The following assumes that TP (R2 or R13) points to the end of the
 121    TCB + 0x7000 (per the ABI).  This implies that TCB address is
 122    TP - 0x7000.  As we define TLS_DTV_AT_TP we can
 123    assume that the pthread struct is allocated immediately ahead of the
 124    TCB.  This implies that the pthread_descr address is
 125    TP - (TLS_PRE_TCB_SIZE + 0x7000).  */
 126 # define TLS_TCB_OFFSET 0x7000
 127
 128 /* Install the dtv pointer.  The pointer passed is to the element with
 129    index -1 which contain the length.  */
 130 # define INSTALL_DTV(tcbp, dtvp) \
 131   ((tcbhead_t *) (tcbp))[-1].dtv = dtvp + 1
 132
 133 /* Install new dtv for current thread.  */
 134 # define INSTALL_NEW_DTV(dtv) (THREAD_DTV() = (dtv))
 135
 136 /* Return dtv of given thread descriptor.  */
 137 # define GET_DTV(tcbp)  (((tcbhead_t *) (tcbp))[-1].dtv)
 138
 139 /* Code to initially initialize the thread pointer.  This might need
 140    special attention since 'errno' is not yet available and if the
 141    operation can cause a failure 'errno' must not be touched.  */
 142 # define TLS_INIT_TP(tcbp) \
 143   ({                                                                          \
 144     __thread_register = (void *) (tcbp) + TLS_TCB_OFFSET;                     \
 145     THREAD_SET_TM_CAPABLE (__tcb_hwcap & PPC_FEATURE2_HAS_HTM ? 1 : 0);       \
 146     THREAD_SET_HWCAP (__tcb_hwcap);                                           \
 147     THREAD_SET_AT_PLATFORM (__tcb_platform);                                  \
 148     NULL;                                                                     \
 149   })
 150
 151 /* Value passed to 'clone' for initialization of the thread register.  */
 152 # define TLS_DEFINE_INIT_TP(tp, pd) \
 153     void *tp = (void *) (pd) + TLS_TCB_OFFSET + TLS_PRE_TCB_SIZE;             \
 154     (((tcbhead_t *) ((char *) tp - TLS_TCB_OFFSET))[-1].tm_capable) =         \
 155       THREAD_GET_TM_CAPABLE ();                                               \
 156     (((tcbhead_t *) ((char *) tp - TLS_TCB_OFFSET))[-1].hwcap) =              \
 157       THREAD_GET_HWCAP ();                                                    \
 158     (((tcbhead_t *) ((char *) tp - TLS_TCB_OFFSET))[-1].at_platform) =        \
 159       THREAD_GET_AT_PLATFORM ();
 160
 161 /* Return the address of the dtv for the current thread.  */
 162 # define THREAD_DTV() \
 163     (((tcbhead_t *) (__thread_register - TLS_TCB_OFFSET))[-1].dtv)
 164
 165 /* Return the thread descriptor for the current thread.  */
 166 # define THREAD_SELF \
 167     ((struct pthread *) (__thread_register \
 168                          - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE))
 169
 170 /* Magic for libthread_db to know how to do THREAD_SELF.  */
 171 # define DB_THREAD_SELF                                                       \
 172   REGISTER (32, 32, PT_THREAD_POINTER * 4,                                    \
 173             - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE)                              \
 174   REGISTER (64, 64, PT_THREAD_POINTER * 8,                                    \
 175             - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE)
 176
 177 /* Read member of the thread descriptor directly.  */
 178 # define THREAD_GETMEM(descr, member) ((void)(descr), (THREAD_SELF)->member)
 179
 180 /* Same as THREAD_GETMEM, but the member offset can be non-constant.  */
 181 # define THREAD_GETMEM_NC(descr, member, idx) \
 182     ((void)(descr), (THREAD_SELF)->member[idx])
 183
 184 /* Set member of the thread descriptor directly.  */
 185 # define THREAD_SETMEM(descr, member, value) \
 186     ((void)(descr), (THREAD_SELF)->member = (value))
 187
 188 /* Same as THREAD_SETMEM, but the member offset can be non-constant.  */
 189 # define THREAD_SETMEM_NC(descr, member, idx, value) \
 190     ((void)(descr), (THREAD_SELF)->member[idx] = (value))
 191
 192 /* Set the stack guard field in TCB head.  */
 193 # define THREAD_SET_STACK_GUARD(value) \
 194     (((tcbhead_t *) ((char *) __thread_register                               \
 195                      - TLS_TCB_OFFSET))[-1].stack_guard = (value))
 196 # define THREAD_COPY_STACK_GUARD(descr) \
 197     (((tcbhead_t *) ((char *) (descr)                                         \
 198                      + TLS_PRE_TCB_SIZE))[-1].stack_guard                     \
 199      = ((tcbhead_t *) ((char *) __thread_register                             \
 200                        - TLS_TCB_OFFSET))[-1].stack_guard)
 201
 202 /* Set the stack guard field in TCB head.  */
 203 # define THREAD_GET_POINTER_GUARD() \
 204     (((tcbhead_t *) ((char *) __thread_register                               \
 205                      - TLS_TCB_OFFSET))[-1].pointer_guard)
 206 # define THREAD_SET_POINTER_GUARD(value) \
 207     (THREAD_GET_POINTER_GUARD () = (value))
 208 # define THREAD_COPY_POINTER_GUARD(descr) \
 209     (((tcbhead_t *) ((char *) (descr)                                         \
 210                      + TLS_PRE_TCB_SIZE))[-1].pointer_guard                   \
 211      = THREAD_GET_POINTER_GUARD())
 212
 213 /* tm_capable field in TCB head.  */
 214 # define THREAD_GET_TM_CAPABLE() \
 215     (((tcbhead_t *) ((char *) __thread_register                               \
 216                      - TLS_TCB_OFFSET))[-1].tm_capable)
 217 # define THREAD_SET_TM_CAPABLE(value) \
 218     (THREAD_GET_TM_CAPABLE () = (value))
 219
 220 /* hwcap field in TCB head.  */
 221 # define THREAD_GET_HWCAP() \
 222     (((tcbhead_t *) ((char *) __thread_register                               \
 223                      - TLS_TCB_OFFSET))[-1].hwcap)
 224 # define THREAD_SET_HWCAP(value) \
 225     (THREAD_GET_HWCAP () = (value))
 226
 227 /* at_platform field in TCB head.  */
 228 # define THREAD_GET_AT_PLATFORM() \
 229     (((tcbhead_t *) ((char *) __thread_register                               \
 230                      - TLS_TCB_OFFSET))[-1].at_platform)
 231 # define THREAD_SET_AT_PLATFORM(value) \
 232     (THREAD_GET_AT_PLATFORM () = (value))
 233
 234 /* l_tls_offset == 0 is perfectly valid on PPC, so we have to use some
 235    different value to mean unset l_tls_offset.  */
 236 # define NO_TLS_OFFSET          -1
 237
 238 /* Get and set the global scope generation counter in struct pthread.  */
 239 #define THREAD_GSCOPE_FLAG_UNUSED 0
 240 #define THREAD_GSCOPE_FLAG_USED   1
 241 #define THREAD_GSCOPE_FLAG_WAIT   2
 242 #define THREAD_GSCOPE_RESET_FLAG() \
 243   do                                                                         \
 244     { int __res                                                              \
 245         = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,             \
 246                                THREAD_GSCOPE_FLAG_UNUSED);                   \
 247       if (__res == THREAD_GSCOPE_FLAG_WAIT)                                  \
 248         lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE);   \
 249     }                                                                        \
 250   while (0)
 251 #define THREAD_GSCOPE_SET_FLAG() \
 252   do                                                                         \
 253     {                                                                        \
 254       THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;             \
 255       atomic_write_barrier ();                                               \
 256     }                                                                        \
 257   while (0)
 258 #define THREAD_GSCOPE_WAIT() \
 259   GL(dl_wait_lookup_done) ()
 260
 261 #endif /* __ASSEMBLER__ */
 262
 263 #endif  /* tls.h */