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/*
* fiber1_generic.c
*
* $Id: fiber1_generic.c,v 1.2 2008/07/11 11:44:32 source Exp $
*
* _fiber_boot and _fiber_switch
* Implementations for simulated threads
*
* This file is part of the OpenLink Software Virtuoso Open-Source (VOS)
* project.
*
* Copyright (C) 1998-2006 OpenLink Software
*
* This project is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; only version 2 of the License, dated June 1991.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*
*/
#include "thread_int.h"
unsigned long context_switches;
/*
* These functions are in a separate file because we do not want the C compiler
* to optimize the calling of them away in any way. The compiler will save
* additional registers before calling the context switch, so our code
* won't crash...
*/
/*
* Every new fiber starts running this function
*/
void
_fiber_boot (thread_t * volatile thr)
{
auto unsigned int marker = THREAD_STACK_MARKER;
int rc;
thr->thr_stack_marker = ▮
/*
* Initially we are called from _fiber_for_thread which does something
* like alloca right after we return
* Remember our context so the fiber can continue with the right stack
*/
if (setjmp (thr->thr_context) == 0)
return;
/* When we get here, the entire stack is garbage. carefully reinitialize */
/* thr->thr_stack_marker is reinitialized elsewhere */
thr = current_thread;
thr->thr_stack_base = (void*) &thr;
/* Store the context so we can easily restart a dead fiber */
setjmp (thr->thr_init_context);
rc = (*thr->thr_initial_function) (thr->thr_initial_argument);
/* Fiber died, put it on the dead queue */
thread_exit (rc);
/* We should NEVER come here */
GPF_T;
}
/*
* The actual context switch
*/
void
_fiber_switch (thread_t *new_thread)
{
context_switches++;
assert (*new_thread->thr_stack_marker == THREAD_STACK_MARKER);
if (setjmp (current_thread->thr_context) == 0)
{
_current_fiber = new_thread;
longjmp (new_thread->thr_context, 1);
}
}
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