linuxthreads/sysdeps/s390/s390-64/pt-machine.h

   1 /* Machine-dependent pthreads configuration and inline functions.
   2    64 bit S/390 version.
   3    Copyright (C) 2001, 2002, 2003 Free Software Foundation, Inc.
   4    Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
   5    This file is part of the GNU C Library.
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Lesser General Public License as
   9    published by the Free Software Foundation; either version 2.1 of the
  10    License, or (at your option) any later version.
  11
  12    The GNU C Library is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Lesser General Public License for more details.
  16
  17    You should have received a copy of the GNU Lesser General Public
  18    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  19    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #ifndef _PT_MACHINE_H
  23 #define _PT_MACHINE_H   1
  24
  25 #ifndef PT_EI
  26 # define PT_EI extern inline __attribute__ ((always_inline))
  27 #endif
  28
  29 extern long int testandset (int *spinlock);
  30 extern int __compare_and_swap (long int *p, long int oldval, long int newval);
  31
  32 /* For multiprocessor systems, we want to ensure all memory accesses
  33    are completed before we reset a lock.  On other systems, we still
  34    need to make sure that the compiler has flushed everything to memory.  */
  35 #define MEMORY_BARRIER() __asm__ __volatile__ ("bcr 15,0" : : : "memory")
  36
  37 /* Spinlock implementation; required.  */
  38 PT_EI long int
  39 testandset (int *spinlock)
  40 {
  41   int ret;
  42
  43   __asm__ __volatile__(
  44        "    la    1,%1\n"
  45        "    lhi   0,1\n"
  46        "    l     %0,%1\n"
  47        "0:  cs    %0,0,0(1)\n"
  48        "    jl    0b"
  49        : "=&d" (ret), "+m" (*spinlock)
  50        : : "0", "1", "cc");
  51
  52   return ret;
  53 }
  54
  55
  56 /* Get some notion of the current stack.  Need not be exactly the top
  57    of the stack, just something somewhere in the current frame.  */
  58 #define CURRENT_STACK_FRAME  stack_pointer
  59 register char * stack_pointer __asm__ ("15");
  60
  61 #ifdef USE_TLS
  62 /* Return the thread descriptor for the current thread.  */
  63 # define THREAD_SELF ((pthread_descr) __builtin_thread_pointer ())
  64
  65 /* Initialize the thread-unique value.  */
  66 #define INIT_THREAD_SELF(descr, nr) __builtin_set_thread_pointer (descr)
  67 #else
  68 /* Return the thread descriptor for the current thread.
  69    64 bit S/390 uses access register 0 and 1 as "thread register".  */
  70 #define THREAD_SELF  ({                                                       \
  71   register pthread_descr __self;                                              \
  72   __asm__ ("   ear  %0,%%a0\n"                                                \
  73            "   sllg %0,%0,32\n"                                               \
  74            "   ear  %0,%%a1\n"                                                \
  75            : "=d" (__self) );                                                 \
  76   __self;                                                                     \
  77 })
  78
  79 /* Initialize the thread-unique value.  */
  80 #define INIT_THREAD_SELF(descr, nr)  ({                                       \
  81   __asm__ ("   sar  %%a1,%0\n"                                                \
  82            "   srlg 0,%0,32\n"                                                \
  83            "   sar  %%a0,0\n"                                                 \
  84            : : "d" (descr) : "0" );                                           \
  85 })
  86 #endif
  87
  88 /* Access to data in the thread descriptor is easy.  */
  89 #define THREAD_GETMEM(descr, member) \
  90   ((void) sizeof (descr), THREAD_SELF->member)
  91 #define THREAD_GETMEM_NC(descr, member) \
  92   ((void) sizeof (descr), THREAD_SELF->member)
  93 #define THREAD_SETMEM(descr, member, value) \
  94   ((void) sizeof (descr), THREAD_SELF->member = (value))
  95 #define THREAD_SETMEM_NC(descr, member, value) \
  96   ((void) sizeof (descr), THREAD_SELF->member = (value))
  97
  98 /* We want the OS to assign stack addresses.  */
  99 #define FLOATING_STACKS 1
 100
 101 /* Maximum size of the stack if the rlimit is unlimited.  */
 102 #define ARCH_STACK_MAX_SIZE     8*1024*1024
 103
 104 /* Compare-and-swap for semaphores. */
 105
 106 #define HAS_COMPARE_AND_SWAP
 107
 108 PT_EI int
 109 __compare_and_swap(long int *p, long int oldval, long int newval)
 110 {
 111         int retval;
 112
 113         __asm__ __volatile__(
 114                 "  lgr  0,%2\n"
 115                 "  csg  0,%3,%1\n"
 116                 "  ipm  %0\n"
 117                 "  srl  %0,28\n"
 118                 "0:"
 119                 : "=&d" (retval), "+m" (*p)
 120                 : "d" (oldval) , "d" (newval)
 121                 : "cc", "0");
 122         return retval == 0;
 123 }
 124
 125 #endif /* pt-machine.h */