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 <adt/list.h>
#include <arch/atomic.h>
#include <proc/thread.h>
 
/** Clock routine
 *
 * Clock routine executed from clock interrupt handler
 * (assuming interrupts_disable()'d). Runs expired timeouts
 * and preemptive scheduling.
 *
 */
void clock(void)
{
    link_t *l;
    timeout_t *h;
    timeout_handler_t 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) {
        __u64 ticks;
       
        spinlock_lock(&CPU->lock);
        CPU->needs_relink++;
        spinlock_unlock(&CPU->lock);   
   
        spinlock_lock(&THREAD->lock);
        if ((ticks = THREAD->ticks))
            THREAD->ticks--;
        spinlock_unlock(&THREAD->lock);
       
        if (!ticks && !PREEMPTION_DISABLED) {
            scheduler();
        }
    }
 
}
 

Rev 615	Rev 788
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 <adt/list.h>
41	#include <arch/atomic.h>	41	#include <arch/atomic.h>
42	#include <proc/thread.h>	42	#include <proc/thread.h>
43		43
44	/** Clock routine	44	/** Clock routine
45	*	45	*
46	* Clock routine executed from clock interrupt handler	46	* Clock routine executed from clock interrupt handler
47	* (assuming interrupts_disable()'d). Runs expired timeouts	47	* (assuming interrupts_disable()'d). Runs expired timeouts
48	* and preemptive scheduling.	48	* and preemptive scheduling.
49	*	49	*
50	*/	50	*/
51	void clock(void)	51	void clock(void)
52	{	52	{
53	link_t *l;	53	link_t *l;
54	timeout_t *h;	54	timeout_t *h;
55	timeout_handler_t f;	55	timeout_handler_t f;
56	void *arg;	56	void *arg;
57		57
58	/*	58	/*
59	* To avoid lock ordering problems,	59	* To avoid lock ordering problems,
60	* run all expired timeouts as you visit them.	60	* run all expired timeouts as you visit them.
61	*/	61	*/
62	spinlock_lock(&CPU->timeoutlock);	62	spinlock_lock(&CPU->timeoutlock);
63	while ((l = CPU->timeout_active_head.next) != &CPU->timeout_active_head) {	63	while ((l = CPU->timeout_active_head.next) != &CPU->timeout_active_head) {
64	h = list_get_instance(l, timeout_t, link);	64	h = list_get_instance(l, timeout_t, link);
65	spinlock_lock(&h->lock);	65	spinlock_lock(&h->lock);
66	if (h->ticks-- != 0) {	66	if (h->ticks-- != 0) {
67	spinlock_unlock(&h->lock);	67	spinlock_unlock(&h->lock);
68	break;	68	break;
69	}	69	}
70	list_remove(l);	70	list_remove(l);
71	f = h->handler;	71	f = h->handler;
72	arg = h->arg;	72	arg = h->arg;
73	timeout_reinitialize(h);	73	timeout_reinitialize(h);
74	spinlock_unlock(&h->lock);	74	spinlock_unlock(&h->lock);
75	spinlock_unlock(&CPU->timeoutlock);	75	spinlock_unlock(&CPU->timeoutlock);
76		76
77	f(arg);	77	f(arg);
78		78
79	spinlock_lock(&CPU->timeoutlock);	79	spinlock_lock(&CPU->timeoutlock);
80	}	80	}
81	spinlock_unlock(&CPU->timeoutlock);	81	spinlock_unlock(&CPU->timeoutlock);
82		82
83	/*	83	/*
84	* Do CPU usage accounting and find out whether to preempt THREAD.	84	* Do CPU usage accounting and find out whether to preempt THREAD.
85	*/	85	*/
86		86
87	if (THREAD) {	87	if (THREAD) {
88	__u64 ticks;	88	__u64 ticks;
89		89
90	spinlock_lock(&CPU->lock);	90	spinlock_lock(&CPU->lock);
91	CPU->needs_relink++;	91	CPU->needs_relink++;
92	spinlock_unlock(&CPU->lock);	92	spinlock_unlock(&CPU->lock);
93		93
94	spinlock_lock(&THREAD->lock);	94	spinlock_lock(&THREAD->lock);
95	if ((ticks = THREAD->ticks))	95	if ((ticks = THREAD->ticks))
96	THREAD->ticks--;	96	THREAD->ticks--;
97	spinlock_unlock(&THREAD->lock);	97	spinlock_unlock(&THREAD->lock);
98		98
99	if (!ticks && !PREEMPTION_DISABLED) {	99	if (!ticks && !PREEMPTION_DISABLED) {
100	scheduler();	100	scheduler();
101	}	101	}
102	}	102	}
103		103
104	}	104	}
105		105

Subversion Repositories HelenOS-historic

(root)/kernel/trunk/generic/src/time/clock.c @ 1164 – Rev 615 → 788