57 lines
1.5 KiB
C
57 lines
1.5 KiB
C
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/*
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* Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of the
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* License, or any later version.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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#include <gpxe/list.h>
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#include <gpxe/process.h>
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/** @file
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*
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* Processes
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*
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* We implement a trivial form of cooperative multitasking, in which
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* all processes share a single stack and address space.
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*/
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/** Process run queue */
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static LIST_HEAD ( run_queue );
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/**
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* Add process to run queue
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*
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* @v process Process
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*/
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void schedule ( struct process *process ) {
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list_add_tail ( &process->list, &run_queue );
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}
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/**
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* Single-step a single process
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*
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* This removes the first process from the run queue and executes a
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* single step of that process.
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*/
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void step ( void ) {
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struct process *process;
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list_for_each_entry ( process, &run_queue, list ) {
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list_del ( &process->list );
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process->step ( process );
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break;
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}
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}
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