*
* @APPLE_LICENSE_HEADER_START@
*
- * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
+ * The contents of this file constitute Original Code as defined in and
+ * are subject to the Apple Public Source License Version 1.1 (the
+ * "License"). You may not use this file except in compliance with the
+ * License. Please obtain a copy of the License at
+ * http://www.apple.com/publicsource and read it before using this file.
*
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * This Original Code and all software distributed under the License are
+ * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
+ * License for the specific language governing rights and limitations
+ * under the License.
*
* @APPLE_LICENSE_HEADER_END@
*/
#ifndef KERNEL
LEAF(_ev_lock)
-
- li a6,1 // lock value
-
-8: lwz a7,0(a0) // Get lock word
- mr. a7,a7 // Is it held?
- bne-- 8b // Yup...
-
-9: lwarx a7,0,a0 // read the lock
- mr. a7,a7 // Is it held?
- bne-- 7f // yes, kill reservation
- stwcx. a6,0,a0 // try to get the lock
- bne-- 9b // failed, try again
- isync
- blr // got it, return
-
-7: li a7,-4 // Point to a spot in the red zone
- stwcx. a7,a7,r1 // Kill reservation
- b 8b // Go wait some more...
-
-
+ li a6,1 // lock value
+ lwarx a7,0,a0 // CEMV10
+9:
+ sync
+ lwarx a7,0,a0 // read the lock
+ cmpwi cr0,a7,0 // is it busy?
+ bne- 9b // yes, spin
+ sync
+ stwcx. a6,0,a0 // try to get the lock
+ bne- 9b // failed, try again
+ isync
+ blr // got it, return
END(_ev_lock)
LEAF(_IOSpinLock)
-
- li a6,1 // lock value
-
-8: lwz a7,0(a0) // Get lock word
- mr. a7,a7 // Is it held?
- bne-- 8b // Yup...
-
-9: lwarx a7,0,a0 // read the lock
- mr. a7,a7 // Is it held?
- bne-- 7f // yes, kill reservation
- stwcx. a6,0,a0 // try to get the lock
- bne-- 9b // failed, try again
- isync
- blr // got it, return
-
-7: li a7,-4 // Point to a spot in the red zone
- stwcx. a7,a7,r1 // Kill reservation
- b 8b // Go wait some more...
+ li a6,1 // lock value
+ lwarx a7,0,a0 // CEMV10
+9:
+ sync
+ lwarx a7,0,a0 // read the lock
+ cmpwi cr0,a7,0 // is it busy?
+ bne- 9b // yes, spin
+ sync
+ stwcx. a6,0,a0 // try to get the lock
+ bne- 9b // failed, try again
+ isync
+ blr // got it, return
END(_IOSpinLock)
#endif
*/
LEAF(_ev_try_lock)
-
- DISABLE_PREEMPTION()
-
- li a6,1 // lock value
-
- lwz a7,0(a0) // Get lock word
- mr. a7,a7 // Is it held?
- bne-- 6f // Yup...
-
-9: lwarx a7,0,a0 // read the lock
- mr. a7,a7 // Is it held?
- bne-- 7f // yes, kill reservation
- stwcx. a6,0,a0 // try to get the lock
- bne-- 9b // failed, try again
- li a0,1 // return TRUE
- isync
- blr // got it, return
-
-7: li a7,-4 // Point to a spot in the red zone
- stwcx. a7,a7,r1 // Kill reservation
-
-6:
- ENABLE_PREEMPTION()
- li a0,0 // return FALSE
- blr
-
+ li a6,1 // lock value
+ DISABLE_PREEMPTION()
+ lwarx a7,0,a0 // CEMV10
+8:
+ sync
+ lwarx a7,0,a0 // read the lock
+ cmpwi cr0,a7,0 // is it busy?
+ bne- 9f // yes, give up
+ sync
+ stwcx. a6,0,a0 // try to get the lock
+ bne- 8b // failed, try again
+ li a0,1 // return TRUE
+ isync
+ blr
+9:
+ ENABLE_PREEMPTION()
+ li a0,0 // return FALSE
+ blr
END(_ev_try_lock)
LEAF(_IOTrySpinLock)
-
- DISABLE_PREEMPTION()
-
- li a6,1 // lock value
-
- lwz a7,0(a0) // Get lock word
- mr. a7,a7 // Is it held?
- bne-- 6f // Yup...
-
-9: lwarx a7,0,a0 // read the lock
- mr. a7,a7 // Is it held?
- bne-- 7f // yes, kill reservation
- stwcx. a6,0,a0 // try to get the lock
- bne-- 9b // failed, try again
- li a0,1 // return TRUE
- isync
- blr // got it, return
-
-7: li a7,-4 // Point to a spot in the red zone
- stwcx. a7,a7,r1 // Kill reservation
-
-6:
- ENABLE_PREEMPTION()
- li a0,0 // return FALSE
- blr
-
+ li a6,1 // lock value
+ DISABLE_PREEMPTION()
+ lwarx a7,0,a0 // CEMV10
+8:
+ sync
+ lwarx a7,0,a0 // read the lock
+ cmpwi cr0,a7,0 // is it busy?
+ bne- 9f // yes, give up
+ sync
+ stwcx. a6,0,a0 // try to get the lock
+ bne- 8b // failed, try again
+ li a0,1 // return TRUE
+ isync
+ blr
+9:
+ ENABLE_PREEMPTION()
+ li a0,0 // return FALSE
+ blr
END(_IOTrySpinLock)
#endif /* ! _IOKIT_IOSHAREDLOCKIMP_H */
projects / apple / xnu.git / blobdiff