diff options
Diffstat (limited to 'asm/lock.S')
| -rw-r--r-- | asm/lock.S | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/asm/lock.S b/asm/lock.S new file mode 100644 index 0000000..ce28010 --- /dev/null +++ b/asm/lock.S @@ -0,0 +1,43 @@ +/* Copyright 2013-2014 IBM Corp. + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or + * implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include <asm-utils.h> +#include <asm-offsets.h> +#include <processor.h> + + .section ".text","ax" + .balign 0x10 + + /* bool try_lock(struct lock *lock) */ +.global __try_lock +__try_lock: + ld %r0,0(%r3) + andi. %r10,%r0,1 + bne 2f + lwz %r9,CPUTHREAD_PIR(%r13) +1: ldarx %r0,0,%r3 + andi. %r10,%r0,1 + bne- 2f + ori %r0,%r0,1 + rldimi %r0,%r9,32,0 + stdcx. %r0,0,%r3 + bne 1b + sync + li %r3,-1 + blr +2: li %r3,0 + blr + |