diff options
Diffstat (limited to 'libpthread/linuxthreads/sysdeps/microblaze/pt-machine.h')
-rw-r--r-- | libpthread/linuxthreads/sysdeps/microblaze/pt-machine.h | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/libpthread/linuxthreads/sysdeps/microblaze/pt-machine.h b/libpthread/linuxthreads/sysdeps/microblaze/pt-machine.h new file mode 100644 index 000000000..e8c03f9e5 --- /dev/null +++ b/libpthread/linuxthreads/sysdeps/microblaze/pt-machine.h @@ -0,0 +1,106 @@ +/* + * sysdeps/microblaze/pt-machine.h -- microblaze-specific pthread definitions + * + * Copyright (C) 2003 John Williams <jwilliams@itee.uq.edu.au> + * Copyright (C) 2002 NEC Electronics Corporation + * Copyright (C) 2002 Miles Bader <miles@gnu.org> + * + * 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. + * + * Written by Miles Bader <miles@gnu.org> + */ + +#ifndef _PT_MACHINE_H +#define _PT_MACHINE_H 1 + +#include <features.h> + +#ifndef PT_EI +# define PT_EI extern inline +#endif + +extern long int testandset (int *spinlock); +extern int __compare_and_swap (long *ptr, long old, long new); + +/* 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__ ("r1"); + +#define HAS_COMPARE_AND_SWAP +#define HAS_COMPARE_AND_SWAP_WITH_RELEASE_SEMANTICS +#define IMPLEMENT_TAS_WITH_CAS + +/* Atomically: If *PTR == OLD, set *PTR to NEW and return true, + otherwise do nothing and return false. */ +PT_EI int __compare_and_swap (long *ptr, long old, long new) +{ + unsigned long psw; + + /* disable interrupts */ + /* This is ugly ugly ugly! */ + __asm__ __volatile__ ("mfs %0, rmsr;" + "andi r3, %0, ~2;" + "mts rmsr, r3;" + : "=&r" (psw) + : + : "r3"); + + if (likely (*ptr == old)) + { + *ptr = new; + __asm__ __volatile__ ("mts rmsr, %0;" :: "r" (psw)); /* re-enable */ + return 1; + } + else + { + __asm__ __volatile__ ("mts rmsr, %0;" :: "r" (psw)); /* re-enable */ + return 0; + } +} + +/* like above's __compare_and_swap() but it first syncs the memory + (This is also the difference between both functions in e.g. + ../powerpc/pt-machine.h) + Doing this additional sync fixes a hang of __pthread_alt_unlock() + (Falk Brettschneider <fbrettschneider@baumeroptronic.de>) */ +PT_EI int +__compare_and_swap_with_release_semantics (long *p, + long oldval, long newval) +{ + __asm__ __volatile__ ("" : : : "memory"); /*MEMORY_BARRIER ();*/ + return __compare_and_swap (p, oldval, newval); +} + + +#ifndef IMPLEMENT_TAS_WITH_CAS +/* Spinlock implementation; required. */ +PT_EI long int testandset (int *spinlock) +{ + unsigned psw; + + /* disable interrupts */ + __asm__ __volatile__ ("mfs %0, rmsr;" + "andi r3, %0, ~2;" + "mts rmsr, r3;" + : "=&r" (psw) + : + : "r3"); + + if (*spinlock) + { + /* Enable ints */ + __asm__ __volatile__ ("mts rmsr, %0;" :: "r" (psw)); + return 1; + } else { + *spinlock=1; + /* Enable ints */ + __asm__ __volatile__ ("mts rmsr, %0;" :: "r" (psw)); + return 0; + } +} + +#endif +#endif /* pt-machine.h */ |