| /* Machine-dependent pthreads configuration and inline functions. |
| * |
| * Copyright (C) 2005-2007 Atmel Corporation |
| * |
| * This file is subject to the terms and conditions of the GNU Lesser General |
| * Public License. See the file "COPYING.LIB" in the main directory of this |
| * archive for more details. |
| */ |
| #ifndef _PT_MACHINE_H |
| #define _PT_MACHINE_H 1 |
| |
| #include <features.h> |
| |
| #ifndef PT_EI |
| # define PT_EI __extern_always_inline |
| #endif |
| |
| static __inline__ int |
| _test_and_set (int *p, int v) |
| { |
| int result; |
| |
| __asm__ __volatile__( |
| "/* Inline test and set */\n" |
| " xchg %[old], %[mem], %[new]" |
| : [old] "=&r"(result) |
| : [mem] "r"(p), [new] "r"(v) |
| : "memory"); |
| |
| return result; |
| } |
| |
| extern long int testandset (int *spinlock); |
| extern int __compare_and_swap (long int *p, long int oldval, long int newval); |
| |
| /* Spinlock implementation; required. */ |
| PT_EI long int |
| testandset (int *spinlock) |
| { |
| return _test_and_set(spinlock, 1); |
| } |
| |
| |
| /* 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"); |
| |
| /* Compare-and-swap for semaphores. */ |
| |
| #define HAS_COMPARE_AND_SWAP |
| PT_EI int |
| __compare_and_swap(long int *p, long int oldval, long int newval) |
| { |
| long int result; |
| |
| __asm__ __volatile__( |
| "/* Inline compare and swap */\n" |
| "1: ssrf 5\n" |
| " ld.w %[result], %[mem]\n" |
| " eor %[result], %[old]\n" |
| " brne 2f\n" |
| " stcond %[mem], %[new]\n" |
| " brne 1b\n" |
| "2:" |
| : [result] "=&r"(result), [mem] "=m"(*p) |
| : "m"(*p), [new] "r"(newval), [old] "r"(oldval) |
| : "cc", "memory"); |
| |
| return result == 0; |
| } |
| |
| #endif /* pt-machine.h */ |