WebSVN – HelenOS – Diff – /branches/sparc/kernel/generic/src/synch/spinlock.c


/*
 * 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
 

Rev 195	Rev 223
1	/*	1	/*
2	* Copyright (C) 2001-2004 Jakub Jermar	2	* Copyright (C) 2001-2004 Jakub Jermar
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	13	* documentation and/or other materials provided with the distribution.
14	* - The name of the author may not be used to endorse or promote products	14	* - The name of the author may not be used to endorse or promote products
15	* derived from this software without specific prior written permission.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	#include <arch.h>	29	#include <arch.h>
30		30
31	#include <arch/atomic.h>	31	#include <arch/atomic.h>
32	#include <arch/barrier.h>	32	#include <arch/barrier.h>
33	#include <synch/spinlock.h>	33	#include <synch/spinlock.h>
-		34	#include <preemption.h>
34	#include <print.h>	35	#include <print.h>
35		36
36	#ifdef __SMP__	37	#ifdef __SMP__
37		38
38	void spinlock_initialize(spinlock_t *sl)	39	void spinlock_initialize(spinlock_t *sl)
39	{	40	{
40	sl->val = 0;	41	sl->val = 0;
41	}	42	}
42		43
43	#ifdef DEBUG_SPINLOCK	44	#ifdef DEBUG_SPINLOCK
44	void spinlock_lock(spinlock_t *sl)	45	void spinlock_lock(spinlock_t *sl)
45	{	46	{
46	int i = 0;	47	int i = 0;
47	__address caller = ((__u32 *) &sl)[-1];	48	__address caller = ((__u32 *) &sl)[-1];
48		49
-		50	preemption_disable();
49	while (test_and_set(&sl->val)) {	51	while (test_and_set(&sl->val)) {
50	if (i++ > 300000) {	52	if (i++ > 300000) {
51	printf("cpu%d: looping on spinlock %X, caller=%X\n", CPU->id, sl, caller);	53	printf("cpu%d: looping on spinlock %X, caller=%X\n", CPU->id, sl, caller);
52	i = 0;	54	i = 0;
53	}	55	}
54	}	56	}
55	CS_ENTER_BARRIER();	57	CS_ENTER_BARRIER();
56		58
57	}	59	}
58	#else	60	#else
59	void spinlock_lock(spinlock_t *sl)	61	void spinlock_lock(spinlock_t *sl)
60	{	62	{
-		63	preemption_disable();
-		64
61	/*	65	/*
62	* Each architecture has its own efficient/recommended	66	* Each architecture has its own efficient/recommended
63	* implementation of spinlock.	67	* implementation of spinlock.
64	*/	68	*/
65	spinlock_arch(&sl->val);	69	spinlock_arch(&sl->val);
66	CS_ENTER_BARRIER();	70	CS_ENTER_BARRIER();
67	}	71	}
68	#endif	72	#endif
69		73
70	int spinlock_trylock(spinlock_t *sl)	74	int spinlock_trylock(spinlock_t *sl)
71	{	75	{
72	int rc;	76	int rc;
73		77
-		78	preemption_disable();
74	rc = !test_and_set(&sl->val);	79	rc = !test_and_set(&sl->val);
75	CS_ENTER_BARRIER();	80	CS_ENTER_BARRIER();
-		81
-		82	if (!rc)
-		83	preemption_enable();
76		84
77	return rc;	85	return rc;
78	}	86	}
79		87
80	void spinlock_unlock(spinlock_t *sl)	88	void spinlock_unlock(spinlock_t *sl)
81	{	89	{
82	CS_LEAVE_BARRIER();	90	CS_LEAVE_BARRIER();
83	sl->val = 0;	91	sl->val = 0;
-		92	preemption_enable();
84	}	93	}
85		94
86	#endif	95	#endif
87		96

Subversion Repositories HelenOS

(root)/branches/sparc/kernel/generic/src/synch/spinlock.c @ 3862 – Rev 195 → 223