WebSVN – HelenOS – Diff – /trunk/uspace/lib/libc/generic/fibril.c


/*
 * Copyright (c) 2006 Ondrej Palkovsky
 * Copyright (c) 2007 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 libc
 * @{
 */
/** @file
 */
 
#include <libadt/list.h>
#include <fibril.h>
#include <malloc.h>
#include <unistd.h>
#include <thread.h>
#include <stdio.h>
#include <libarch/faddr.h>
#include <futex.h>
#include <assert.h>
#include <async.h>
 
#ifndef FIBRIL_INITIAL_STACK_PAGES_NO
#define FIBRIL_INITIAL_STACK_PAGES_NO   1
#endif
 
/** This futex serializes access to ready_list, serialized_list and manage_list.
 */
static atomic_t fibril_futex = FUTEX_INITIALIZER;
 
static LIST_INITIALIZE(ready_list);
static LIST_INITIALIZE(serialized_list);
static LIST_INITIALIZE(manager_list);
 
static void fibril_main(void);
 
/** Number of fibrils that are in async_serialized mode */
static int serialized_fibrils;  /* Protected by async_futex */
/** Thread-local count of serialization. If >0, we must not preempt */
static __thread int serialization_count;
/** Counter for fibrils residing in async_manager */
static int fibrils_in_manager;
 
/** Setup fibril information into TCB structure */
fibril_t *fibril_setup(void)
{
    fibril_t *f;
    tcb_t *tcb;
 
    tcb = __make_tls();
    if (!tcb)
        return NULL;
 
    f = malloc(sizeof(*f));
    if (!f) {
        __free_tls(tcb);
        return NULL;
    }
 
    tcb->fibril_data = f;
    f->tcb = tcb;
 
    return f;
}
 
void fibril_teardown(fibril_t *f)
{
    __free_tls(f->tcb);
    free(f);
}
 
/** Function that spans the whole life-cycle of a fibril.
 *
 * Each fibril begins execution in this function. Then the function implementing
 * the fibril logic is called.  After its return, the return value is saved.
 * The fibril then switches to another fibril, which cleans up after it.
 */
void fibril_main(void)
{
    fibril_t *f = __tcb_get()->fibril_data;
 
    /* Call the implementing function. */
    f->retval = f->func(f->arg);
 
    fibril_schedule_next_adv(FIBRIL_FROM_DEAD);
    /* not reached */
}
 
/** Schedule next fibril.
 *
 * If calling with FIBRIL_TO_MANAGER parameter, the async_futex should be
 * held.
 *
 * @param stype     Switch type. One of FIBRIL_PREEMPT, FIBRIL_TO_MANAGER,
 *          FIBRIL_FROM_MANAGER, FIBRIL_FROM_DEAD. The parameter
 *          describes the circumstances of the switch.
 * @return      Return 0 if there is no ready fibril,
 *          return 1 otherwise.
 */
int fibril_schedule_next_adv(fibril_switch_type_t stype)
{
    fibril_t *srcf, *dstf;
    int retval = 0;
   
    futex_down(&fibril_futex);
 
    if (stype == FIBRIL_PREEMPT && list_empty(&ready_list))
        goto ret_0;
 
    if (stype == FIBRIL_FROM_MANAGER) {
        if (list_empty(&ready_list) && list_empty(&serialized_list))
            goto ret_0;
        /*
         * Do not preempt if there is not sufficient count of fibril
         * managers.
         */
        if (list_empty(&serialized_list) && fibrils_in_manager <=
            serialized_fibrils) {
            goto ret_0;
        }
    }
    /* If we are going to manager and none exists, create it */
    if (stype == FIBRIL_TO_MANAGER || stype == FIBRIL_FROM_DEAD) {
        while (list_empty(&manager_list)) {
            futex_up(&fibril_futex);
            async_create_manager();
            futex_down(&fibril_futex);
        }
    }
   
    srcf = __tcb_get()->fibril_data;
    if (stype != FIBRIL_FROM_DEAD) {
        /* Save current state */
        if (!context_save(&srcf->ctx)) {
            if (serialization_count)
                srcf->flags &= ~FIBRIL_SERIALIZED;
            if (srcf->clean_after_me) {
                /*
                 * Cleanup after the dead fibril from which we
                 * restored context here.
                 */
                free(srcf->clean_after_me->stack);
                fibril_teardown(srcf->clean_after_me);
                srcf->clean_after_me = NULL;
            }
            return 1;   /* futex_up already done here */
        }
 
        /* Save myself to the correct run list */
        if (stype == FIBRIL_PREEMPT)
            list_append(&srcf->link, &ready_list);
        else if (stype == FIBRIL_FROM_MANAGER) {
            list_append(&srcf->link, &manager_list);
            fibrils_in_manager--;
        } else {   
            /*
             * If stype == FIBRIL_TO_MANAGER, don't put ourselves to
             * any list, we should already be somewhere, or we will
             * be lost.
             */
        }
    }
 
    /* Choose a new fibril to run */
    if (stype == FIBRIL_TO_MANAGER || stype == FIBRIL_FROM_DEAD) {
        dstf = list_get_instance(manager_list.next, fibril_t, link);
        if (serialization_count && stype == FIBRIL_TO_MANAGER) {
            serialized_fibrils++;
            srcf->flags |= FIBRIL_SERIALIZED;
        }
        fibrils_in_manager++;
 
        if (stype == FIBRIL_FROM_DEAD)
            dstf->clean_after_me = srcf;
    } else {
        if (!list_empty(&serialized_list)) {
            dstf = list_get_instance(serialized_list.next, fibril_t,
                link);
            serialized_fibrils--;
        } else {
            dstf = list_get_instance(ready_list.next, fibril_t,
                link);
        }
    }
    list_remove(&dstf->link);
 
    futex_up(&fibril_futex);
    context_restore(&dstf->ctx);
    /* not reached */
 
ret_0:
    futex_up(&fibril_futex);
    return retval;
}
 
/** Create a new fibril.
 *
 * @param func      Implementing function of the new fibril.
 * @param arg       Argument to pass to func.
 *
 * @return      Return 0 on failure or TLS of the new fibril.
 */
fid_t fibril_create(int (*func)(void *), void *arg)
{
    fibril_t *f;
 
    f = fibril_setup();
    if (!f)
        return 0;
    f->stack = (char *) malloc(FIBRIL_INITIAL_STACK_PAGES_NO *
        getpagesize());
 
    if (!f->stack) {
        fibril_teardown(f);
        return 0;
    }
 
    f->arg = arg;
    f->func = func;
    f->clean_after_me = NULL;
    f->retval = 0;
    f->flags = 0;
 
    context_save(&f->ctx);
    context_set(&f->ctx, FADDR(fibril_main), f->stack,
        FIBRIL_INITIAL_STACK_PAGES_NO * getpagesize(), f->tcb);
 
    return (fid_t) f;
}
 
/** Add a fibril to the ready list.
 *
 * @param fid       Pinter to the fibril structure of the fibril to be
 *          added.
 */
void fibril_add_ready(fid_t fid)
{
    fibril_t *f;
 
    f = (fibril_t *) fid;
    futex_down(&fibril_futex);
    if ((f->flags & FIBRIL_SERIALIZED))
        list_append(&f->link, &serialized_list);
    else
        list_append(&f->link, &ready_list);
    futex_up(&fibril_futex);
}
 
/** Add a fibril to the manager list.
 *
 * @param fid       Pinter to the fibril structure of the fibril to be added.
 */
void fibril_add_manager(fid_t fid)
{
    fibril_t *f;
 
    f = (fibril_t *) fid;
 
    futex_down(&fibril_futex);
    list_append(&f->link, &manager_list);
    futex_up(&fibril_futex);
}
 
/** Remove one manager from the manager list. */
void fibril_remove_manager(void)
{
    futex_down(&fibril_futex);
    if (list_empty(&manager_list)) {
        futex_up(&fibril_futex);
        return;
    }
    list_remove(manager_list.next);
    futex_up(&fibril_futex);
}
 
/** Return fibril id of the currently running fibril.
 *
 * @return      Fibril ID of the currently running pseudo thread.
 */
fid_t fibril_get_id(void)
{
    return (fid_t) __tcb_get()->fibril_data;
}
 
/** Disable preemption
 *
 * If the fibril wants to send several message in a row and does not want to be
 * preempted, it should start async_serialize_start() in the beginning of
 * communication and async_serialize_end() in the end. If it is a true
 * multithreaded application, it should protect the communication channel by a
 * futex as well. Interrupt messages can still be preempted.
 */
void fibril_inc_sercount(void)
{
    serialization_count++;
}
 
/** Restore the preemption counter to the previous state. */
void fibril_dec_sercount(void)
{
    serialization_count--;
}
 
/** @}
 */
 
 

Rev 2483	Rev 2492
1	/*	1	/*
2	* Copyright (c) 2006 Ondrej Palkovsky	2	* Copyright (c) 2006 Ondrej Palkovsky
3	* Copyright (c) 2007 Jakub Jermar	3	* Copyright (c) 2007 Jakub Jermar
4	* All rights reserved.	4	* All rights reserved.
5	*	5	*
6	* Redistribution and use in source and binary forms, with or without	6	* Redistribution and use in source and binary forms, with or without
7	* modification, are permitted provided that the following conditions	7	* modification, are permitted provided that the following conditions
8	* are met:	8	* are met:
9	*	9	*
10	* - Redistributions of source code must retain the above copyright	10	* - Redistributions of source code must retain the above copyright
11	* notice, this list of conditions and the following disclaimer.	11	* notice, this list of conditions and the following disclaimer.
12	* - Redistributions in binary form must reproduce the above copyright	12	* - Redistributions in binary form must reproduce the above copyright
13	* notice, this list of conditions and the following disclaimer in the	13	* notice, this list of conditions and the following disclaimer in the
14	* documentation and/or other materials provided with the distribution.	14	* documentation and/or other materials provided with the distribution.
15	* - The name of the author may not be used to endorse or promote products	15	* - The name of the author may not be used to endorse or promote products
16	* derived from this software without specific prior written permission.	16	* derived from this software without specific prior written permission.
17	*	17	*
18	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	18	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	19	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	20	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	21	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	22	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	23	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	24	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	25	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	26	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	27	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28	*/	28	*/
29		29
30	/** @addtogroup libc	30	/** @addtogroup libc
31	* @{	31	* @{
32	*/	32	*/
33	/** @file	33	/** @file
34	*/	34	*/
35		35
36	#include <libadt/list.h>	36	#include <libadt/list.h>
37	#include <fibril.h>	37	#include <fibril.h>
38	#include <malloc.h>	38	#include <malloc.h>
39	#include <unistd.h>	39	#include <unistd.h>
40	#include <thread.h>	40	#include <thread.h>
41	#include <stdio.h>	41	#include <stdio.h>
42	#include <libarch/faddr.h>	42	#include <libarch/faddr.h>
43	#include <futex.h>	43	#include <futex.h>
44	#include <assert.h>	44	#include <assert.h>
45	#include <async.h>	45	#include <async.h>
46		46
47	#ifndef FIBRIL_INITIAL_STACK_PAGES_NO	47	#ifndef FIBRIL_INITIAL_STACK_PAGES_NO
48	#define FIBRIL_INITIAL_STACK_PAGES_NO 1	48	#define FIBRIL_INITIAL_STACK_PAGES_NO 1
49	#endif	49	#endif
50		50
51	/** This futex serializes access to ready_list, serialized_list and manage_list.	51	/** This futex serializes access to ready_list, serialized_list and manage_list.
52	*/	52	*/
53	static atomic_t fibril_futex = FUTEX_INITIALIZER;	53	static atomic_t fibril_futex = FUTEX_INITIALIZER;
54		54
55	static LIST_INITIALIZE(ready_list);	55	static LIST_INITIALIZE(ready_list);
56	static LIST_INITIALIZE(serialized_list);	56	static LIST_INITIALIZE(serialized_list);
57	static LIST_INITIALIZE(manager_list);	57	static LIST_INITIALIZE(manager_list);
58		58
59	static void fibril_main(void);	59	static void fibril_main(void);
60		60
61	/** Number of fibrils that are in async_serialized mode */	61	/** Number of fibrils that are in async_serialized mode */
62	static int serialized_fibrils; /* Protected by async_futex */	62	static int serialized_fibrils; /* Protected by async_futex */
63	/** Thread-local count of serialization. If >0, we must not preempt */	63	/** Thread-local count of serialization. If >0, we must not preempt */
64	static __thread int serialization_count;	64	static __thread int serialization_count;
65	/** Counter for fibrils residing in async_manager */	65	/** Counter for fibrils residing in async_manager */
66	static int fibrils_in_manager;	66	static int fibrils_in_manager;
67		67
68	/** Setup fibril information into TCB structure */	68	/** Setup fibril information into TCB structure */
69	fibril_t *fibril_setup(void)	69	fibril_t *fibril_setup(void)
70	{	70	{
71	fibril_t *f;	71	fibril_t *f;
72	tcb_t *tcb;	72	tcb_t *tcb;
73		73
74	tcb = __make_tls();	74	tcb = __make_tls();
75	if (!tcb)	75	if (!tcb)
76	return NULL;	76	return NULL;
77		77
78	f = malloc(sizeof(*f));	78	f = malloc(sizeof(*f));
79	if (!f) {	79	if (!f) {
80	__free_tls(tcb);	80	__free_tls(tcb);
81	return NULL;	81	return NULL;
82	}	82	}
83		83
84	tcb->fibril_data = f;	84	tcb->fibril_data = f;
85	f->tcb = tcb;	85	f->tcb = tcb;
86		86
87	return f;	87	return f;
88	}	88	}
89		89
90	void fibril_teardown(fibril_t *f)	90	void fibril_teardown(fibril_t *f)
91	{	91	{
92	__free_tls(f->tcb);	92	__free_tls(f->tcb);
93	free(f);	93	free(f);
94	}	94	}
95		95
96	/** Function that spans the whole life-cycle of a fibril.	96	/** Function that spans the whole life-cycle of a fibril.
97	*	97	*
98	* Each fibril begins execution in this function. Then the function implementing	98	* Each fibril begins execution in this function. Then the function implementing
99	* the fibril logic is called. After its return, the return value is saved.	99	* the fibril logic is called. After its return, the return value is saved.
100	* The fibril then switches to another fibril, which cleans up after it.	100	* The fibril then switches to another fibril, which cleans up after it.
101	*/	101	*/
102	void fibril_main(void)	102	void fibril_main(void)
103	{	103	{
104	fibril_t *f = __tcb_get()->fibril_data;	104	fibril_t *f = __tcb_get()->fibril_data;
105		105
106	/* Call the implementing function. */	106	/* Call the implementing function. */
107	f->retval = f->func(f->arg);	107	f->retval = f->func(f->arg);
108		108
109	fibril_schedule_next_adv(FIBRIL_FROM_DEAD);	109	fibril_schedule_next_adv(FIBRIL_FROM_DEAD);
110	/* not reached */	110	/* not reached */
111	}	111	}
112		112
113	/** Schedule next fibril.	113	/** Schedule next fibril.
114	*	114	*
115	* If calling with FIBRIL_TO_MANAGER parameter, the async_futex should be	115	* If calling with FIBRIL_TO_MANAGER parameter, the async_futex should be
116	* held.	116	* held.
117	*	117	*
118	* @param stype Switch type. One of FIBRIL_PREEMPT, FIBRIL_TO_MANAGER,	118	* @param stype Switch type. One of FIBRIL_PREEMPT, FIBRIL_TO_MANAGER,
119	* FIBRIL_FROM_MANAGER, FIBRIL_FROM_DEAD. The parameter	119	* FIBRIL_FROM_MANAGER, FIBRIL_FROM_DEAD. The parameter
120	* describes the circumstances of the switch.	120	* describes the circumstances of the switch.
121	* @return Return 0 if there is no ready fibril,	121	* @return Return 0 if there is no ready fibril,
122	* return 1 otherwise.	122	* return 1 otherwise.
123	*/	123	*/
124	int fibril_schedule_next_adv(fibril_switch_type_t stype)	124	int fibril_schedule_next_adv(fibril_switch_type_t stype)
125	{	125	{
126	fibril_t srcf, dstf;	126	fibril_t srcf, dstf;
127	int retval = 0;	127	int retval = 0;
128		128
129	futex_down(&fibril_futex);	129	futex_down(&fibril_futex);
130		130
131	if (stype == FIBRIL_PREEMPT && list_empty(&ready_list))	131	if (stype == FIBRIL_PREEMPT && list_empty(&ready_list))
132	goto ret_0;	132	goto ret_0;
133		133
134	if (stype == FIBRIL_FROM_MANAGER) {	134	if (stype == FIBRIL_FROM_MANAGER) {
135	if (list_empty(&ready_list) && list_empty(&serialized_list))	135	if (list_empty(&ready_list) && list_empty(&serialized_list))
136	goto ret_0;	136	goto ret_0;
137	/*	137	/*
138	* Do not preempt if there is not sufficient count of fibril	138	* Do not preempt if there is not sufficient count of fibril
139	* managers.	139	* managers.
140	*/	140	*/
141	if (list_empty(&serialized_list) && fibrils_in_manager <=	141	if (list_empty(&serialized_list) && fibrils_in_manager <=
142	serialized_fibrils) {	142	serialized_fibrils) {
143	goto ret_0;	143	goto ret_0;
144	}	144	}
145	}	145	}
146	/* If we are going to manager and none exists, create it */	146	/* If we are going to manager and none exists, create it */
147	if (stype == FIBRIL_TO_MANAGER \|\| stype == FIBRIL_FROM_DEAD) {	147	if (stype == FIBRIL_TO_MANAGER \|\| stype == FIBRIL_FROM_DEAD) {
148	while (list_empty(&manager_list)) {	148	while (list_empty(&manager_list)) {
149	futex_up(&fibril_futex);	149	futex_up(&fibril_futex);
150	async_create_manager();	150	async_create_manager();
151	futex_down(&fibril_futex);	151	futex_down(&fibril_futex);
152	}	152	}
153	}	153	}
154		154
155	srcf = __tcb_get()->fibril_data;	155	srcf = __tcb_get()->fibril_data;
156	if (stype != FIBRIL_FROM_DEAD) {	156	if (stype != FIBRIL_FROM_DEAD) {
157	/* Save current state */	157	/* Save current state */
158	if (!context_save(&srcf->ctx)) {	158	if (!context_save(&srcf->ctx)) {
159	if (serialization_count)	159	if (serialization_count)
160	srcf->flags &= ~FIBRIL_SERIALIZED;	160	srcf->flags &= ~FIBRIL_SERIALIZED;
161	if (srcf->clean_after_me) {	161	if (srcf->clean_after_me) {
162	/*	162	/*
163	* Cleanup after the dead fibril from which we	163	* Cleanup after the dead fibril from which we
164	* restored context here.	164	* restored context here.
165	*/	165	*/
166	free(srcf->clean_after_me->stack);	166	free(srcf->clean_after_me->stack);
167	fibril_teardown(srcf->clean_after_me);	167	fibril_teardown(srcf->clean_after_me);
168	srcf->clean_after_me = NULL;	168	srcf->clean_after_me = NULL;
169	}	169	}
170	return 1; /* futex_up already done here */	170	return 1; /* futex_up already done here */
171	}	171	}
172		172
173	/* Save myself to the correct run list */	173	/* Save myself to the correct run list */
174	if (stype == FIBRIL_PREEMPT)	174	if (stype == FIBRIL_PREEMPT)
175	list_append(&srcf->link, &ready_list);	175	list_append(&srcf->link, &ready_list);
176	else if (stype == FIBRIL_FROM_MANAGER) {	176	else if (stype == FIBRIL_FROM_MANAGER) {
177	list_append(&srcf->link, &manager_list);	177	list_append(&srcf->link, &manager_list);
178	fibrils_in_manager--;	178	fibrils_in_manager--;
179	} else {	179	} else {
180	/*	180	/*
181	* If stype == FIBRIL_TO_MANAGER, don't put ourselves to	181	* If stype == FIBRIL_TO_MANAGER, don't put ourselves to
182	* any list, we should already be somewhere, or we will	182	* any list, we should already be somewhere, or we will
183	* be lost.	183	* be lost.
184	*/	184	*/
185	}	185	}
186	}	186	}
187		187
188	/* Choose a new fibril to run */	188	/* Choose a new fibril to run */
189	if (stype == FIBRIL_TO_MANAGER \|\| stype == FIBRIL_FROM_DEAD) {	189	if (stype == FIBRIL_TO_MANAGER \|\| stype == FIBRIL_FROM_DEAD) {
190	dstf = list_get_instance(manager_list.next, fibril_t, link);	190	dstf = list_get_instance(manager_list.next, fibril_t, link);
191	if (serialization_count && stype == FIBRIL_TO_MANAGER) {	191	if (serialization_count && stype == FIBRIL_TO_MANAGER) {
192	serialized_fibrils++;	192	serialized_fibrils++;
193	srcf->flags \|= FIBRIL_SERIALIZED;	193	srcf->flags \|= FIBRIL_SERIALIZED;
194	}	194	}
195	fibrils_in_manager++;	195	fibrils_in_manager++;
196		196
197	if (stype == FIBRIL_FROM_DEAD)	197	if (stype == FIBRIL_FROM_DEAD)
198	dstf->clean_after_me = srcf;	198	dstf->clean_after_me = srcf;
199	} else {	199	} else {
200	if (!list_empty(&serialized_list)) {	200	if (!list_empty(&serialized_list)) {
201	dstf = list_get_instance(serialized_list.next, fibril_t,	201	dstf = list_get_instance(serialized_list.next, fibril_t,
202	link);	202	link);
203	serialized_fibrils--;	203	serialized_fibrils--;
204	} else {	204	} else {
205	dstf = list_get_instance(ready_list.next, fibril_t,	205	dstf = list_get_instance(ready_list.next, fibril_t,
206	link);	206	link);
207	}	207	}
208	}	208	}
209	list_remove(&dstf->link);	209	list_remove(&dstf->link);
210		210
211	futex_up(&fibril_futex);	211	futex_up(&fibril_futex);
212	context_restore(&dstf->ctx);	212	context_restore(&dstf->ctx);
213	/* not reached */	213	/* not reached */
214		214
215	ret_0:	215	ret_0:
216	futex_up(&fibril_futex);	216	futex_up(&fibril_futex);
217	return retval;	217	return retval;
218	}	218	}
219		219
220	/** Create a new fibril.	220	/** Create a new fibril.
221	*	221	*
222	* @param func Implementing function of the new fibril.	222	* @param func Implementing function of the new fibril.
223	* @param arg Argument to pass to func.	223	* @param arg Argument to pass to func.
224	*	224	*
225	* @return Return 0 on failure or TLS of the new fibril.	225	* @return Return 0 on failure or TLS of the new fibril.
226	*/	226	*/
227	fid_t fibril_create(int (func)(void ), void *arg)	227	fid_t fibril_create(int (func)(void ), void *arg)
228	{	228	{
229	fibril_t *f;	229	fibril_t *f;
230		230
231	f = fibril_setup();	231	f = fibril_setup();
232	if (!f)	232	if (!f)
233	return 0;	233	return 0;
234	f->stack = (char ) malloc(FIBRIL_INITIAL_STACK_PAGES_NO	234	f->stack = (char ) malloc(FIBRIL_INITIAL_STACK_PAGES_NO
235	getpagesize());	235	getpagesize());
236		236
237	if (!f->stack) {	237	if (!f->stack) {
238	fibril_teardown(f);	238	fibril_teardown(f);
239	return 0;	239	return 0;
240	}	240	}
241		241
242	f->arg = arg;	242	f->arg = arg;
243	f->func = func;	243	f->func = func;
244	f->clean_after_me = NULL;	244	f->clean_after_me = NULL;
245	f->retval = 0;	245	f->retval = 0;
246	f->flags = 0;	246	f->flags = 0;
247		247
248	context_save(&f->ctx);	248	context_save(&f->ctx);
249	context_set(&f->ctx, FADDR(fibril_main), f->stack,	249	context_set(&f->ctx, FADDR(fibril_main), f->stack,
250	FIBRIL_INITIAL_STACK_PAGES_NO * getpagesize(), f->tcb);	250	FIBRIL_INITIAL_STACK_PAGES_NO * getpagesize(), f->tcb);
251		251
252	return (fid_t) f;	252	return (fid_t) f;
253	}	253	}
254		254
255	/** Add a fibril to the ready list.	255	/** Add a fibril to the ready list.
256	*	256	*
257	* @param fid Pinter to the fibril structure of the fibril to be added.	257	* @param fid Pinter to the fibril structure of the fibril to be
-		258	* added.
258	*/	259	*/
259	void fibril_add_ready(fid_t fid)	260	void fibril_add_ready(fid_t fid)
260	{	261	{
261	fibril_t *f;	262	fibril_t *f;
262		263
263	f = (fibril_t *) fid;	264	f = (fibril_t *) fid;
264	futex_down(&fibril_futex);	265	futex_down(&fibril_futex);
265	if ((f->flags & FIBRIL_SERIALIZED))	266	if ((f->flags & FIBRIL_SERIALIZED))
266	list_append(&f->link, &serialized_list);	267	list_append(&f->link, &serialized_list);
267	else	268	else
268	list_append(&f->link, &ready_list);	269	list_append(&f->link, &ready_list);
269	futex_up(&fibril_futex);	270	futex_up(&fibril_futex);
270	}	271	}
271		272
272	/** Add a fibril to the manager list.	273	/** Add a fibril to the manager list.
273	*	274	*
274	* @param fid Pinter to the fibril structure of the fibril to be added.	275	* @param fid Pinter to the fibril structure of the fibril to be added.
275	*/	276	*/
276	void fibril_add_manager(fid_t fid)	277	void fibril_add_manager(fid_t fid)
277	{	278	{
278	fibril_t *f;	279	fibril_t *f;
279		280
280	f = (fibril_t *) fid;	281	f = (fibril_t *) fid;
281		282
282	futex_down(&fibril_futex);	283	futex_down(&fibril_futex);
283	list_append(&f->link, &manager_list);	284	list_append(&f->link, &manager_list);
284	futex_up(&fibril_futex);	285	futex_up(&fibril_futex);
285	}	286	}
286		287
287	/** Remove one manager from the manager list. */	288	/** Remove one manager from the manager list. */
288	void fibril_remove_manager(void)	289	void fibril_remove_manager(void)
289	{	290	{
290	futex_down(&fibril_futex);	291	futex_down(&fibril_futex);
291	if (list_empty(&manager_list)) {	292	if (list_empty(&manager_list)) {
292	futex_up(&fibril_futex);	293	futex_up(&fibril_futex);
293	return;	294	return;
294	}	295	}
295	list_remove(manager_list.next);	296	list_remove(manager_list.next);
296	futex_up(&fibril_futex);	297	futex_up(&fibril_futex);
297	}	298	}
298		299
299	/** Return fibril id of the currently running fibril.	300	/** Return fibril id of the currently running fibril.
300	*	301	*
301	* @return Fibril ID of the currently running pseudo thread.	302	* @return Fibril ID of the currently running pseudo thread.
302	*/	303	*/
303	fid_t fibril_get_id(void)	304	fid_t fibril_get_id(void)
304	{	305	{
305	return (fid_t) __tcb_get()->fibril_data;	306	return (fid_t) __tcb_get()->fibril_data;
306	}	307	}
307		308
308	/** Disable preemption	309	/** Disable preemption
309	*	310	*
310	* If the fibril wants to send several message in a row and does not want to be	311	* If the fibril wants to send several message in a row and does not want to be
311	* preempted, it should start async_serialize_start() in the beginning of	312	* preempted, it should start async_serialize_start() in the beginning of
312	* communication and async_serialize_end() in the end. If it is a true	313	* communication and async_serialize_end() in the end. If it is a true
313	* multithreaded application, it should protect the communication channel by a	314	* multithreaded application, it should protect the communication channel by a
314	* futex as well. Interrupt messages can still be preempted.	315	* futex as well. Interrupt messages can still be preempted.
315	*/	316	*/
316	void fibril_inc_sercount(void)	317	void fibril_inc_sercount(void)
317	{	318	{
318	serialization_count++;	319	serialization_count++;
319	}	320	}
320		321
321	/** Restore the preemption counter to the previous state. */	322	/** Restore the preemption counter to the previous state. */
322	void fibril_dec_sercount(void)	323	void fibril_dec_sercount(void)
323	{	324	{
324	serialization_count--;	325	serialization_count--;
325	}	326	}
326		327
327	/** @}	328	/** @}
328	*/	329	*/
329		330
330		331

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(root)/trunk/uspace/lib/libc/generic/fibril.c – Rev 2483 → 2492