diff options
Diffstat (limited to 'lib/libc_r/arch/powerpc/_atomic_lock.c')
| -rw-r--r-- | lib/libc_r/arch/powerpc/_atomic_lock.c | 37 |
1 files changed, 0 insertions, 37 deletions
diff --git a/lib/libc_r/arch/powerpc/_atomic_lock.c b/lib/libc_r/arch/powerpc/_atomic_lock.c deleted file mode 100644 index d248b4725cf..00000000000 --- a/lib/libc_r/arch/powerpc/_atomic_lock.c +++ /dev/null @@ -1,37 +0,0 @@ -/* $OpenBSD: _atomic_lock.c,v 1.5 2002/11/12 18:56:28 drahn Exp $ */ -/* - * Atomic lock for powerpc - */ - -#include "spinlock.h" - -int -_atomic_lock(volatile _spinlock_lock_t *lock) -{ - _spinlock_lock_t old; - - __asm__("1: lwarx 0,0,%1 \n" - " stwcx. %2,0,%1 \n" - " bne- 1b \n" - " mr %0, 0 \n" - : "=r" (old), "=r" (lock) - : "r" (_SPINLOCK_LOCKED), "1" (lock) : "0" - ); - - return (old != _SPINLOCK_UNLOCKED); - - /* - * Dale <rahnds@openbsd.org> says: - * Side note. to prevent two processes from accessing - * the same address with the lwarx in one instrution - * and the stwcx in another process, the current powerpc - * kernel uses a stwcx instruction without the corresponding - * lwarx which causes any reservation of a process - * to be removed. if a context switch occurs - * between the two accesses the store will not occur - * and the condition code will cause it to loop. If on - * a dual processor machine, the reserve will cause - * appropriate bus cycle accesses to notify other - * processors. - */ -} |