Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 | /* Machine-dependent pthreads configuration and inline functions. ARM version. Copyright (C) 1997, 1998, 2000, 2002 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Philip Blundell <philb@gnu.org>. 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; see the file COPYING.LIB. If not, see <http://www.gnu.org/licenses/>. */ #ifndef _PT_MACHINE_H #define _PT_MACHINE_H 1 #include <sys/syscall.h> #include <unistd.h> #ifndef PT_EI # define PT_EI __extern_always_inline #endif #if defined(__thumb2__) PT_EI long int ldrex(int *spinlock) { long int ret; __asm__ __volatile__( "ldrex %0, [%1]\n" : "=r"(ret) : "r"(spinlock) : "memory"); return ret; } PT_EI long int strex(int val, int *spinlock) { long int ret; __asm__ __volatile__( "strex %0, %1, [%2]\n" : "=r"(ret) : "r" (val), "r"(spinlock) : "memory"); return ret; } /* Spinlock implementation; required. */ PT_EI long int testandset (int *spinlock) { register unsigned int ret; do { ret = ldrex(spinlock); } while (strex(1, spinlock)); return ret; } #elif defined(__thumb__) /* This will not work on ARM1 or ARM2 because SWP is lacking on those machines. Unfortunately we have no way to detect this at compile time; let's hope nobody tries to use one. */ /* Spinlock implementation; required. */ PT_EI long int testandset (int *spinlock); PT_EI long int testandset (int *spinlock) { register unsigned int ret; void *pc; __asm__ __volatile__( ".align 0\n" "\tbx pc\n" "\tnop\n" "\t.arm\n" "\tswp %0, %2, [%3]\n" "\torr %1, pc, #1\n" "\tbx %1\n" "\t.force_thumb" : "=r"(ret), "=r"(pc) : "0"(1), "r"(spinlock)); return ret; } #else /* __thumb__ */ PT_EI long int testandset (int *spinlock); PT_EI long int testandset (int *spinlock) { register unsigned int ret; __asm__ __volatile__("swp %0, %1, [%2]" : "=r"(ret) : "0"(1), "r"(spinlock)); return ret; } #endif /* Get some notion of the current stack. Need not be exactly the top of the stack, just something somewhere in the current frame. */ #define CURRENT_STACK_FRAME stack_pointer register char * stack_pointer __asm__ ("sp"); #endif /* pt-machine.h */ |