0,0 → 1,193 |
/* |
* Copyright (C) 2006 Ondrej Palkovsky |
* 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 <libadt/list.h> |
#include <psthread.h> |
#include <malloc.h> |
#include <unistd.h> |
#include <thread.h> |
#include <stdio.h> |
#include <kernel/arch/faddr.h> |
|
|
#ifndef PSTHREAD_INITIAL_STACK_PAGES_NO |
#define PSTHREAD_INITIAL_STACK_PAGES_NO 1 |
#endif |
|
static LIST_INITIALIZE(ready_list); |
|
static void psthread_exit(void) __attribute__ ((noinline)); |
static void psthread_main(void); |
|
/** Setup PSthread information into TCB structure */ |
psthread_data_t * psthread_setup(tcb_t *tcb) |
{ |
psthread_data_t *pt; |
|
pt = malloc(sizeof(*pt)); |
if (!pt) { |
return NULL; |
} |
|
tcb->pst_data = pt; |
pt->tcb = tcb; |
|
return pt; |
} |
|
void psthread_teardown(psthread_data_t *pt) |
{ |
free(pt); |
} |
|
/** Function to preempt to other pseudo thread without adding |
* currently running pseudo thread to ready_list. |
*/ |
void psthread_exit(void) |
{ |
psthread_data_t *pt; |
|
if (list_empty(&ready_list)) { |
/* Wait on IPC queue etc... */ |
printf("Cannot exit!!!\n"); |
_exit(0); |
} |
pt = list_get_instance(ready_list.next, psthread_data_t, link); |
list_remove(&pt->link); |
context_restore(&pt->ctx); |
} |
|
/** Function that is called on entry to new uspace thread */ |
void psthread_main(void) |
{ |
psthread_data_t *pt = __tcb_get()->pst_data; |
|
pt->retval = pt->func(pt->arg); |
|
pt->finished = 1; |
if (pt->waiter) |
list_append(&pt->waiter->link, &ready_list); |
|
psthread_exit(); |
} |
|
/** Schedule next userspace pseudo thread. |
* |
* @return 0 if there is no ready pseudo thread, 1 otherwise. |
*/ |
int psthread_schedule_next(void) |
{ |
psthread_data_t *pt; |
|
if (list_empty(&ready_list)) |
return 0; |
|
pt = __tcb_get()->pst_data; |
if (!context_save(&pt->ctx)) |
return 1; |
|
list_append(&pt->link, &ready_list); |
pt = list_get_instance(ready_list.next, psthread_data_t, link); |
list_remove(&pt->link); |
|
context_restore(&pt->ctx); |
} |
|
/** Wait for uspace pseudo thread to finish. |
* |
* @param psthrid Pseudo thread to wait for. |
* |
* @return Value returned by the finished thread. |
*/ |
int psthread_join(pstid_t psthrid) |
{ |
volatile psthread_data_t *pt, *mypt; |
volatile int retval; |
|
/* Handle psthrid = Kernel address -> it is wait for call */ |
pt = (psthread_data_t *) psthrid; |
|
if (!pt->finished) { |
mypt = __tcb_get()->pst_data; |
if (context_save(&((psthread_data_t *) mypt)->ctx)) { |
pt->waiter = (psthread_data_t *) mypt; |
psthread_exit(); |
} |
} |
retval = pt->retval; |
|
free(pt->stack); |
__free_tls(pt->tcb); |
psthread_teardown((void *)pt); |
|
return retval; |
} |
|
/** |
* Create a userspace thread and append it to ready list. |
* |
* @param func Pseudo thread function. |
* @param arg Argument to pass to func. |
* |
* @return 0 on failure, TLS of the new pseudo thread. |
*/ |
pstid_t psthread_create(int (*func)(void *), void *arg) |
{ |
psthread_data_t *pt; |
tcb_t *tcb; |
|
tcb = __make_tls(); |
if (!tcb) |
return 0; |
|
pt = psthread_setup(tcb); |
if (!pt) { |
__free_tls(tcb); |
return 0; |
} |
pt->stack = (char *) malloc(PSTHREAD_INITIAL_STACK_PAGES_NO*getpagesize()); |
|
if (!pt->stack) { |
__free_tls(tcb); |
psthread_teardown(pt); |
return 0; |
} |
|
pt->arg= arg; |
pt->func = func; |
pt->finished = 0; |
pt->waiter = NULL; |
|
context_save(&pt->ctx); |
context_set(&pt->ctx, FADDR(psthread_main), pt->stack, PSTHREAD_INITIAL_STACK_PAGES_NO*getpagesize(), |
tcb); |
|
list_append(&pt->link, &ready_list); |
|
return (pstid_t )pt; |
} |