WebSVN – HelenOS-historic – Diff – /kernel/trunk/generic/src/time/clock.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 <time/clock.h>
#include <time/timeout.h>
#include <arch/types.h>
#include <config.h>
#include <synch/spinlock.h>
#include <synch/waitq.h>
#include <func.h>
#include <proc/scheduler.h>
#include <cpu.h>
#include <print.h>
#include <arch.h>
#include <list.h>
 
#ifdef __SMP__
#include <arch/smp/atomic.h>
#endif
 
/** Clock routine
 *
 * Clock routine executed from clock interrupt handler
 * (assuming cpu_priority_high()). Runs expired timeouts
 * and preemptive scheduling.
 *
 */
void clock(void)
{
    link_t *l;
    timeout_t *h;
    timeout_handler f;
    void *arg;
 
    /*
     * To avoid lock ordering problems,
     * run all expired timeouts as you visit them.
     */
    spinlock_lock(&CPU->timeoutlock);
    while ((l = CPU->timeout_active_head.next) != &CPU->timeout_active_head) {
        h = list_get_instance(l, timeout_t, link);
        spinlock_lock(&h->lock);
        if (h->ticks-- != 0) {
            spinlock_unlock(&h->lock);
            break;
        }
        list_remove(l);
        f = h->handler;
        arg = h->arg;
        timeout_reinitialize(h);
        spinlock_unlock(&h->lock); 
        spinlock_unlock(&CPU->timeoutlock);
 
        f(arg);
 
        spinlock_lock(&CPU->timeoutlock);
    }
    spinlock_unlock(&CPU->timeoutlock);
 
    /*
     * Do CPU usage accounting and find out whether to preempt THREAD.
     */
 
    if (THREAD) {
        spinlock_lock(&CPU->lock);
        CPU->needs_relink++;
        spinlock_unlock(&CPU->lock);   
   
        spinlock_lock(&THREAD->lock);
            if (!THREAD->ticks--) {
            spinlock_unlock(&THREAD->lock);
            scheduler();
        }
        else {
            spinlock_unlock(&THREAD->lock);
        }
    }
 
}
 

Rev 15	Rev 107
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 <time/clock.h>	29	#include <time/clock.h>
30	#include <time/timeout.h>	30	#include <time/timeout.h>
31	#include <arch/types.h>	31	#include <arch/types.h>
32	#include <config.h>	32	#include <config.h>
33	#include <synch/spinlock.h>	33	#include <synch/spinlock.h>
34	#include <synch/waitq.h>	34	#include <synch/waitq.h>
35	#include <func.h>	35	#include <func.h>
36	#include <proc/scheduler.h>	36	#include <proc/scheduler.h>
37	#include <cpu.h>	37	#include <cpu.h>
38	#include <print.h>	38	#include <print.h>
39	#include <arch.h>	39	#include <arch.h>
40	#include <list.h>	40	#include <list.h>
41		41
42	#ifdef __SMP__	42	#ifdef __SMP__
43	#include <arch/smp/atomic.h>	43	#include <arch/smp/atomic.h>
44	#endif	44	#endif
45		45
-		46	/** Clock routine
46	/*	47	*
47	* Clock is called from an interrupt and is cpu_priority_high()'d.	48	* Clock routine executed from clock interrupt handler
-		49	* (assuming cpu_priority_high()). Runs expired timeouts
-		50	* and preemptive scheduling.
-		51	*
48	*/	52	*/
49	void clock(void)	53	void clock(void)
50	{	54	{
51	link_t *l;	55	link_t *l;
52	timeout_t *h;	56	timeout_t *h;
53	timeout_handler f;	57	timeout_handler f;
54	void *arg;	58	void *arg;
55		59
56	/*	60	/*
57	* To avoid lock ordering problems,	61	* To avoid lock ordering problems,
58	* run all expired timeouts as you visit them.	62	* run all expired timeouts as you visit them.
59	*/	63	*/
60	spinlock_lock(&CPU->timeoutlock);	64	spinlock_lock(&CPU->timeoutlock);
61	while ((l = CPU->timeout_active_head.next) != &CPU->timeout_active_head) {	65	while ((l = CPU->timeout_active_head.next) != &CPU->timeout_active_head) {
62	h = list_get_instance(l, timeout_t, link);	66	h = list_get_instance(l, timeout_t, link);
63	spinlock_lock(&h->lock);	67	spinlock_lock(&h->lock);
64	if (h->ticks-- != 0) {	68	if (h->ticks-- != 0) {
65	spinlock_unlock(&h->lock);	69	spinlock_unlock(&h->lock);
66	break;	70	break;
67	}	71	}
68	list_remove(l);	72	list_remove(l);
69	f = h->handler;	73	f = h->handler;
70	arg = h->arg;	74	arg = h->arg;
71	timeout_reinitialize(h);	75	timeout_reinitialize(h);
72	spinlock_unlock(&h->lock);	76	spinlock_unlock(&h->lock);
73	spinlock_unlock(&CPU->timeoutlock);	77	spinlock_unlock(&CPU->timeoutlock);
74		78
75	f(arg);	79	f(arg);
76		80
77	spinlock_lock(&CPU->timeoutlock);	81	spinlock_lock(&CPU->timeoutlock);
78	}	82	}
79	spinlock_unlock(&CPU->timeoutlock);	83	spinlock_unlock(&CPU->timeoutlock);
80		84
81	/*	85	/*
82	* Do CPU usage accounting and find out whether to preempt THREAD.	86	* Do CPU usage accounting and find out whether to preempt THREAD.
83	*/	87	*/
84		88
85	if (THREAD) {	89	if (THREAD) {
86	spinlock_lock(&CPU->lock);	90	spinlock_lock(&CPU->lock);
87	CPU->needs_relink++;	91	CPU->needs_relink++;
88	spinlock_unlock(&CPU->lock);	92	spinlock_unlock(&CPU->lock);
89		93
90	spinlock_lock(&THREAD->lock);	94	spinlock_lock(&THREAD->lock);
91	if (!THREAD->ticks--) {	95	if (!THREAD->ticks--) {
92	spinlock_unlock(&THREAD->lock);	96	spinlock_unlock(&THREAD->lock);
93	scheduler();	97	scheduler();
94	}	98	}
95	else {	99	else {
96	spinlock_unlock(&THREAD->lock);	100	spinlock_unlock(&THREAD->lock);
97	}	101	}
98	}	102	}
99		103
100	}	104	}
101		105

Subversion Repositories HelenOS-historic

(root)/kernel/trunk/generic/src/time/clock.c @ 1757 – Rev 15 → 107