| 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; |
| } |