source: mainline/libc/generic/thread.c@ c0535f80

/*
 * Copyright (C) 2006 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 <thread.h>
#include <libc.h>
#include <stdlib.h>
#include <arch/faddr.h>
#include <kernel/proc/uarg.h>
#include <psthread.h>
#include <string.h>

#include <stdio.h>


#ifndef THREAD_INITIAL_STACK_PAGES_NO
#define THREAD_INITIAL_STACK_PAGES_NO 1
#endif


extern char _tdata_start;
extern char _tdata_end;
extern char _tbss_start;
extern char _tbss_end;

/** Create Thread Local storage area, return pointer to TCB(ThreadControlBlock)
 *
 * !! The code requires, that sections .tdata and .tbss are adjacent.
 *    It may be changed in the future.
 */
tcb_t * __make_tls(void)
{
        void *data;
        tcb_t *tcb;
        size_t tls_size = &_tbss_end - &_tdata_start;
        
        tcb = __alloc_tls(&data, tls_size);
        
        memcpy(data, &_tdata_start, &_tdata_end - &_tdata_start);
        memset(data + (&_tbss_start-&_tdata_start), &_tbss_end-&_tbss_start, 0);

        return tcb;
}

void __free_tls(tcb_t *tcb)
{
        size_t tls_size = &_tbss_end - &_tdata_start;
        __free_tls_arch(tcb, tls_size);
}

/** Main thread function.
 *
 * This function is called from __thread_entry() and is used
 * to call the thread's implementing function and perform cleanup
 * and exit when thread returns back. Do not call this function
 * directly.
 *
 * @param uarg Pointer to userspace argument structure.
 */
void __thread_main(uspace_arg_t *uarg)
{
        tcb_t *tcb;
        /* This should initialize the area according to TLS specicification */
        tcb = __make_tls();
        __tcb_set(tcb);
        psthread_setup(tcb);

        uarg->uspace_thread_function(uarg->uspace_thread_arg);
        free(uarg->uspace_stack);
        free(uarg);

        psthread_teardown(tcb->pst_data);
        __free_tls(tcb);

        thread_exit(0);
}

/** Create userspace thread.
 *
 * This function creates new userspace thread and allocates userspace
 * stack and userspace argument structure for it.
 *
 * @param function Function implementing the thread.
 * @param arg Argument to be passed to thread.
 * @param name Symbolic name of the thread.
 *
 * @param TID of the new thread on success or -1 on failure.
 */
int thread_create(void (* function)(void *), void *arg, char *name)
{
        char *stack;
        uspace_arg_t *uarg;

        stack = (char *) malloc(getpagesize()*THREAD_INITIAL_STACK_PAGES_NO);
        if (!stack)
                return -1;
                
        uarg = (uspace_arg_t *) malloc(sizeof(uspace_arg_t));
        if (!uarg) {
                free(stack);
                return -1;
        }
        
        uarg->uspace_entry = (void *) FADDR(__thread_entry);
        uarg->uspace_stack = (void *) stack;
        uarg->uspace_thread_function = function;
        uarg->uspace_thread_arg = arg;
        uarg->uspace_uarg = uarg;
        
        return __SYSCALL2(SYS_THREAD_CREATE, (sysarg_t) uarg, (sysarg_t) name);
}

/** Terminate current thread.
 *
 * @param stat Exit status. Currently not used.
 */
void thread_exit(int status)
{
        __SYSCALL1(SYS_THREAD_EXIT, (sysarg_t) status);
}