WebSVN – HelenOS – Diff – /branches/sparc/kernel/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.
 */
 
/** @addtogroup time
 * @{
 */
 
/**
 * @file
 * @brief   High-level clock interrupt handler.
 *
 * This file contains the clock() function which is the source
 * of preemption. It is also responsible for executing expired
 * timeouts.
 */
 
#include <time/clock.h>
#include <time/timeout.h>
#include <config.h>
#include <synch/spinlock.h>
#include <synch/waitq.h>
#include <func.h>
#include <proc/scheduler.h>
#include <cpu.h>
#include <arch.h>
#include <adt/list.h>
#include <atomic.h>
#include <proc/thread.h>
#include <sysinfo/sysinfo.h>
#include <arch/asm.h>
#include <arch/barrier.h>
#include <mm/frame.h>
#include <ddi/ddi.h>
 
/* Pointer to variable with uptime */
uptime_t *uptime;
 
/** Physical memory area of the real time clock */
static parea_t clock_parea;
 
/* Variable holding fragment of second, so that we would update
 * seconds correctly
 */
static unative_t secfrag = 0;
 
/** Initialize realtime clock counter
 *
 * The applications (and sometimes kernel) need to access accurate
 * information about realtime data. We allocate 1 page with these
 * data and update it periodically.
 */
void clock_counter_init(void)
{
    void *faddr;
 
    faddr = frame_alloc(ONE_FRAME, FRAME_ATOMIC);
    if (!faddr)
        panic("Cannot allocate page for clock");
   
    uptime = (uptime_t *) PA2KA(faddr);
   
    uptime->seconds1 = 0;
    uptime->seconds2 = 0;
    uptime->useconds = 0;
 
    clock_parea.pbase = (uintptr_t) faddr;
    clock_parea.vbase = (uintptr_t) uptime;
    clock_parea.frames = 1;
    clock_parea.cacheable = true;
    ddi_parea_register(&clock_parea);
 
    /*
     * Prepare information for the userspace so that it can successfully
     * physmem_map() the clock_parea.
     */
    sysinfo_set_item_val("clock.cacheable", NULL, (unative_t) true);
    sysinfo_set_item_val("clock.faddr", NULL, (unative_t) faddr);
}
 
 
/** Update public counters
 *
 * Update it only on first processor
 * TODO: Do we really need so many write barriers?
 */
static void clock_update_counters(void)
{
    if (CPU->id == 0) {
        secfrag += 1000000 / HZ;
        if (secfrag >= 1000000) {
            secfrag -= 1000000;
            uptime->seconds1++;
            write_barrier();
            uptime->useconds = secfrag;
            write_barrier();
            uptime->seconds2 = uptime->seconds1;
        } else
            uptime->useconds += 1000000 / HZ;
    }
}
 
/** 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;
    count_t missed_clock_ticks = CPU->missed_clock_ticks;
    unsigned int i;
 
    /*
     * To avoid lock ordering problems,
     * run all expired timeouts as you visit them.
     */
    for (i = 0; i <= missed_clock_ticks; i++) {
        clock_update_counters();
        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);
    }
    CPU->missed_clock_ticks = 0;
 
    /*
     * Do CPU usage accounting and find out whether to preempt THREAD.
     */
 
    if (THREAD) {
        uint64_t ticks;
       
        spinlock_lock(&CPU->lock);
        CPU->needs_relink += 1 + missed_clock_ticks;
        spinlock_unlock(&CPU->lock);   
   
        spinlock_lock(&THREAD->lock);
        if ((ticks = THREAD->ticks)) {
            if (ticks >= 1 + missed_clock_ticks)
                THREAD->ticks -= 1 + missed_clock_ticks;
            else
                THREAD->ticks = 0;
        }
        spinlock_unlock(&THREAD->lock);
       
        if (!ticks && !PREEMPTION_DISABLED) {
#ifdef CONFIG_UDEBUG
            istate_t *istate;
#endif
            scheduler();
#ifdef CONFIG_UDEBUG
            /*
             * Give udebug chance to stop the thread
             * before it begins executing userspace code.
             */
            istate = THREAD->udebug.uspace_state;
            if (istate && istate_from_uspace(istate))
                udebug_before_thread_runs();
#endif
        }
    }
 
}
 
/** @}
 */
 

Rev 3742	Rev 3862
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	/** @addtogroup time	29	/** @addtogroup time
30	* @{	30	* @{
31	*/	31	*/
32		32
33	/**	33	/**
34	* @file	34	* @file
35	* @brief High-level clock interrupt handler.	35	* @brief High-level clock interrupt handler.
36	*	36	*
37	* This file contains the clock() function which is the source	37	* This file contains the clock() function which is the source
38	* of preemption. It is also responsible for executing expired	38	* of preemption. It is also responsible for executing expired
39	* timeouts.	39	* timeouts.
40	*/	40	*/
41		41
42	#include <time/clock.h>	42	#include <time/clock.h>
43	#include <time/timeout.h>	43	#include <time/timeout.h>
44	#include <config.h>	44	#include <config.h>
45	#include <synch/spinlock.h>	45	#include <synch/spinlock.h>
46	#include <synch/waitq.h>	46	#include <synch/waitq.h>
47	#include <func.h>	47	#include <func.h>
48	#include <proc/scheduler.h>	48	#include <proc/scheduler.h>
49	#include <cpu.h>	49	#include <cpu.h>
50	#include <arch.h>	50	#include <arch.h>
51	#include <adt/list.h>	51	#include <adt/list.h>
52	#include <atomic.h>	52	#include <atomic.h>
53	#include <proc/thread.h>	53	#include <proc/thread.h>
54	#include <sysinfo/sysinfo.h>	54	#include <sysinfo/sysinfo.h>
-		55	#include <arch/asm.h>
55	#include <arch/barrier.h>	56	#include <arch/barrier.h>
56	#include <mm/frame.h>	57	#include <mm/frame.h>
57	#include <ddi/ddi.h>	58	#include <ddi/ddi.h>
58		59
59	/* Pointer to variable with uptime */	60	/* Pointer to variable with uptime */
60	uptime_t *uptime;	61	uptime_t *uptime;
61		62
62	/** Physical memory area of the real time clock */	63	/** Physical memory area of the real time clock */
63	static parea_t clock_parea;	64	static parea_t clock_parea;
64		65
65	/* Variable holding fragment of second, so that we would update	66	/* Variable holding fragment of second, so that we would update
66	* seconds correctly	67	* seconds correctly
67	*/	68	*/
68	static unative_t secfrag = 0;	69	static unative_t secfrag = 0;
69		70
70	/** Initialize realtime clock counter	71	/** Initialize realtime clock counter
71	*	72	*
72	* The applications (and sometimes kernel) need to access accurate	73	* The applications (and sometimes kernel) need to access accurate
73	* information about realtime data. We allocate 1 page with these	74	* information about realtime data. We allocate 1 page with these
74	* data and update it periodically.	75	* data and update it periodically.
75	*/	76	*/
76	void clock_counter_init(void)	77	void clock_counter_init(void)
77	{	78	{
78	void *faddr;	79	void *faddr;
79		80
80	faddr = frame_alloc(ONE_FRAME, FRAME_ATOMIC);	81	faddr = frame_alloc(ONE_FRAME, FRAME_ATOMIC);
81	if (!faddr)	82	if (!faddr)
82	panic("Cannot allocate page for clock");	83	panic("Cannot allocate page for clock");
83		84
84	uptime = (uptime_t *) PA2KA(faddr);	85	uptime = (uptime_t *) PA2KA(faddr);
85		86
86	uptime->seconds1 = 0;	87	uptime->seconds1 = 0;
87	uptime->seconds2 = 0;	88	uptime->seconds2 = 0;
88	uptime->useconds = 0;	89	uptime->useconds = 0;
89		90
90	clock_parea.pbase = (uintptr_t) faddr;	91	clock_parea.pbase = (uintptr_t) faddr;
91	clock_parea.vbase = (uintptr_t) uptime;	92	clock_parea.vbase = (uintptr_t) uptime;
92	clock_parea.frames = 1;	93	clock_parea.frames = 1;
93	clock_parea.cacheable = true;	94	clock_parea.cacheable = true;
94	ddi_parea_register(&clock_parea);	95	ddi_parea_register(&clock_parea);
95		96
96	/*	97	/*
97	* Prepare information for the userspace so that it can successfully	98	* Prepare information for the userspace so that it can successfully
98	* physmem_map() the clock_parea.	99	* physmem_map() the clock_parea.
99	*/	100	*/
100	sysinfo_set_item_val("clock.cacheable", NULL, (unative_t) true);	101	sysinfo_set_item_val("clock.cacheable", NULL, (unative_t) true);
101	sysinfo_set_item_val("clock.faddr", NULL, (unative_t) faddr);	102	sysinfo_set_item_val("clock.faddr", NULL, (unative_t) faddr);
102	}	103	}
103		104
104		105
105	/** Update public counters	106	/** Update public counters
106	*	107	*
107	* Update it only on first processor	108	* Update it only on first processor
108	* TODO: Do we really need so many write barriers?	109	* TODO: Do we really need so many write barriers?
109	*/	110	*/
110	static void clock_update_counters(void)	111	static void clock_update_counters(void)
111	{	112	{
112	if (CPU->id == 0) {	113	if (CPU->id == 0) {
113	secfrag += 1000000 / HZ;	114	secfrag += 1000000 / HZ;
114	if (secfrag >= 1000000) {	115	if (secfrag >= 1000000) {
115	secfrag -= 1000000;	116	secfrag -= 1000000;
116	uptime->seconds1++;	117	uptime->seconds1++;
117	write_barrier();	118	write_barrier();
118	uptime->useconds = secfrag;	119	uptime->useconds = secfrag;
119	write_barrier();	120	write_barrier();
120	uptime->seconds2 = uptime->seconds1;	121	uptime->seconds2 = uptime->seconds1;
121	} else	122	} else
122	uptime->useconds += 1000000 / HZ;	123	uptime->useconds += 1000000 / HZ;
123	}	124	}
124	}	125	}
125		126
126	/** Clock routine	127	/** Clock routine
127	*	128	*
128	* Clock routine executed from clock interrupt handler	129	* Clock routine executed from clock interrupt handler
129	* (assuming interrupts_disable()'d). Runs expired timeouts	130	* (assuming interrupts_disable()'d). Runs expired timeouts
130	* and preemptive scheduling.	131	* and preemptive scheduling.
131	*	132	*
132	*/	133	*/
133	void clock(void)	134	void clock(void)
134	{	135	{
135	link_t *l;	136	link_t *l;
136	timeout_t *h;	137	timeout_t *h;
137	timeout_handler_t f;	138	timeout_handler_t f;
138	void *arg;	139	void *arg;
139	count_t missed_clock_ticks = CPU->missed_clock_ticks;	140	count_t missed_clock_ticks = CPU->missed_clock_ticks;
140	unsigned int i;	141	unsigned int i;
141		142
142	/*	143	/*
143	* To avoid lock ordering problems,	144	* To avoid lock ordering problems,
144	* run all expired timeouts as you visit them.	145	* run all expired timeouts as you visit them.
145	*/	146	*/
146	for (i = 0; i <= missed_clock_ticks; i++) {	147	for (i = 0; i <= missed_clock_ticks; i++) {
147	clock_update_counters();	148	clock_update_counters();
148	spinlock_lock(&CPU->timeoutlock);	149	spinlock_lock(&CPU->timeoutlock);
149	while ((l = CPU->timeout_active_head.next) != &CPU->timeout_active_head) {	150	while ((l = CPU->timeout_active_head.next) != &CPU->timeout_active_head) {
150	h = list_get_instance(l, timeout_t, link);	151	h = list_get_instance(l, timeout_t, link);
151	spinlock_lock(&h->lock);	152	spinlock_lock(&h->lock);
152	if (h->ticks-- != 0) {	153	if (h->ticks-- != 0) {
153	spinlock_unlock(&h->lock);	154	spinlock_unlock(&h->lock);
154	break;	155	break;
155	}	156	}
156	list_remove(l);	157	list_remove(l);
157	f = h->handler;	158	f = h->handler;
158	arg = h->arg;	159	arg = h->arg;
159	timeout_reinitialize(h);	160	timeout_reinitialize(h);
160	spinlock_unlock(&h->lock);	161	spinlock_unlock(&h->lock);
161	spinlock_unlock(&CPU->timeoutlock);	162	spinlock_unlock(&CPU->timeoutlock);
162		163
163	f(arg);	164	f(arg);
164		165
165	spinlock_lock(&CPU->timeoutlock);	166	spinlock_lock(&CPU->timeoutlock);
166	}	167	}
167	spinlock_unlock(&CPU->timeoutlock);	168	spinlock_unlock(&CPU->timeoutlock);
168	}	169	}
169	CPU->missed_clock_ticks = 0;	170	CPU->missed_clock_ticks = 0;
170		171
171	/*	172	/*
172	* Do CPU usage accounting and find out whether to preempt THREAD.	173	* Do CPU usage accounting and find out whether to preempt THREAD.
173	*/	174	*/
174		175
175	if (THREAD) {	176	if (THREAD) {
176	uint64_t ticks;	177	uint64_t ticks;
177		178
178	spinlock_lock(&CPU->lock);	179	spinlock_lock(&CPU->lock);
179	CPU->needs_relink += 1 + missed_clock_ticks;	180	CPU->needs_relink += 1 + missed_clock_ticks;
180	spinlock_unlock(&CPU->lock);	181	spinlock_unlock(&CPU->lock);
181		182
182	spinlock_lock(&THREAD->lock);	183	spinlock_lock(&THREAD->lock);
183	if ((ticks = THREAD->ticks)) {	184	if ((ticks = THREAD->ticks)) {
184	if (ticks >= 1 + missed_clock_ticks)	185	if (ticks >= 1 + missed_clock_ticks)
185	THREAD->ticks -= 1 + missed_clock_ticks;	186	THREAD->ticks -= 1 + missed_clock_ticks;
186	else	187	else
187	THREAD->ticks = 0;	188	THREAD->ticks = 0;
188	}	189	}
189	spinlock_unlock(&THREAD->lock);	190	spinlock_unlock(&THREAD->lock);
190		191
191	if (!ticks && !PREEMPTION_DISABLED) {	192	if (!ticks && !PREEMPTION_DISABLED) {
192	#ifdef CONFIG_UDEBUG	193	#ifdef CONFIG_UDEBUG
193	istate_t *istate;	194	istate_t *istate;
194	#endif	195	#endif
195	scheduler();	196	scheduler();
196	#ifdef CONFIG_UDEBUG	197	#ifdef CONFIG_UDEBUG
197	/*	198	/*
198	* Give udebug chance to stop the thread	199	* Give udebug chance to stop the thread
199	* before it begins executing userspace code.	200	* before it begins executing userspace code.
200	*/	201	*/
201	istate = THREAD->udebug.uspace_state;	202	istate = THREAD->udebug.uspace_state;
202	if (istate && istate_from_uspace(istate))	203	if (istate && istate_from_uspace(istate))
203	udebug_before_thread_runs();	204	udebug_before_thread_runs();
204	#endif	205	#endif
205	}	206	}
206	}	207	}
207		208
208	}	209	}
209		210
210	/** @}	211	/** @}
211	*/	212	*/
212		213

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(root)/branches/sparc/kernel/generic/src/time/clock.c – Rev 3742 → 3862