0,0 → 1,95 |
/* |
* Copyright (C) 2001-2004 Jakub Jermar |
* All rights reserved. |
* |
* Redistribution and use in source and binary forms, with or without |
* modification, are permitted provided that the following conditions |
* are met: |
* |
* - Redistributions of source code must retain the above copyright |
* notice, this list of conditions and the following disclaimer. |
* - Redistributions in binary form must reproduce the above copyright |
* notice, this list of conditions and the following disclaimer in the |
* documentation and/or other materials provided with the distribution. |
* - The name of the author may not be used to endorse or promote products |
* derived from this software without specific prior written permission. |
* |
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
*/ |
|
#include <arch.h> |
|
#include <arch/atomic.h> |
#include <arch/barrier.h> |
#include <synch/spinlock.h> |
#include <preemption.h> |
#include <print.h> |
|
#ifdef __SMP__ |
|
void spinlock_initialize(spinlock_t *sl) |
{ |
sl->val = 0; |
} |
|
#ifdef DEBUG_SPINLOCK |
void spinlock_lock(spinlock_t *sl) |
{ |
int i = 0; |
__address caller = ((__u32 *) &sl)[-1]; |
|
preemption_disable(); |
while (test_and_set(&sl->val)) { |
if (i++ > 300000) { |
printf("cpu%d: looping on spinlock %X, caller=%X\n", CPU->id, sl, caller); |
i = 0; |
} |
} |
CS_ENTER_BARRIER(); |
|
} |
#else |
void spinlock_lock(spinlock_t *sl) |
{ |
preemption_disable(); |
|
/* |
* Each architecture has its own efficient/recommended |
* implementation of spinlock. |
*/ |
spinlock_arch(&sl->val); |
CS_ENTER_BARRIER(); |
} |
#endif |
|
int spinlock_trylock(spinlock_t *sl) |
{ |
int rc; |
|
preemption_disable(); |
rc = !test_and_set(&sl->val); |
CS_ENTER_BARRIER(); |
|
if (!rc) |
preemption_enable(); |
|
return rc; |
} |
|
void spinlock_unlock(spinlock_t *sl) |
{ |
CS_LEAVE_BARRIER(); |
sl->val = 0; |
preemption_enable(); |
} |
|
#endif |