1 /* Machine-dependent pthreads configuration and inline functions.
3 Copyright (C) 1997-2002, 2003 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5 Contributed by Richard Henderson <rth@tamu.edu>.
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.
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.
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
19 not, see <http://www.gnu.org/licenses/>. */
22 #define _PT_MACHINE_H 1
25 # define PT_EI __extern_always_inline
28 extern long int testandset (int *spinlock);
29 extern int __compare_and_swap (long int *p, long int oldval, long int newval);
31 /* Spinlock implementation; required. */
33 testandset (int *spinlock)
37 __asm__ __volatile__("ldstub %1,%0"
38 : "=r" (ret), "=m" (*spinlock) : "m" (*spinlock));
44 /* Memory barrier; default is to do nothing */
45 #define MEMORY_BARRIER() \
46 __asm__ __volatile__("membar #LoadLoad | #LoadStore | #StoreLoad | #StoreStore" : : : "memory")
48 #define READ_MEMORY_BARRIER() \
49 __asm__ __volatile__("membar #LoadLoad | #LoadStore" : : : "memory")
51 #define WRITE_MEMORY_BARRIER() \
52 __asm__ __volatile__("membar #StoreLoad | #StoreStore" : : : "memory")
55 /* Get some notion of the current stack. Need not be exactly the top
56 of the stack, just something somewhere in the current frame. */
57 #define CURRENT_STACK_FRAME (stack_pointer + (2 * 128))
58 register char *stack_pointer __asm__ ("%sp");
61 /* Registers %g6 and %g7 are reserved by the ABI for "system use". The
62 TLS ABI specifies %g7 as the thread pointer. */
63 struct _pthread_descr_struct;
64 register struct _pthread_descr_struct *__thread_self __asm__ ("%g7");
66 /* Return the thread descriptor for the current thread. */
67 #define THREAD_SELF __thread_self
69 /* Initialize the thread-unique value. */
70 #define INIT_THREAD_SELF(descr, nr) (__thread_self = (descr))
73 /* Compare-and-swap for semaphores. */
75 #define HAS_COMPARE_AND_SWAP
77 __compare_and_swap (long int *p, long int oldval, long int newval)
81 __asm__ __volatile__ ("casx [%4], %2, %0"
82 : "=r"(readval), "=m"(*p)
83 : "r"(oldval), "m"(*p), "r"(p), "0"(newval));
85 return readval == oldval;
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))
98 /* We want the OS to assign stack addresses. */
99 #define FLOATING_STACKS 1
101 /* Maximum size of the stack if the rlimit is unlimited. */
102 #define ARCH_STACK_MAX_SIZE 32*1024*1024
104 #endif /* pt-machine.h */