base/include/rtai_wd.h

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/*
 * Development of this (watchdog) module was sponsored by Alcatel, Strasbourg
 * as part of general debugging enhancements to RTAI.
 *
 * Copyright (©) 2001 Ian Soanes <ians@lineo.com>, All rights reserved
 *
 * This program 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; either version 2 of the
 * License, or (at your option) any later version.
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#ifndef _RTAI_WD_H
#define _RTAI_WD_H

#include <rtai_types.h>

// Useful bits and pieces
#define NSECS_PER_SEC 1000000000

// For logging stuff
#define WDLOG(fmt, args...) rt_printk("RTAI[watchdog]: " fmt, ##args)

// What should happen to misbehaving tasks
typedef enum watchdog_policy { 
    WD_NOTHING,                 // Not recommended
    WD_RESYNC,              // Good for occasional overruns
    WD_DEBUG,               // Good for debugging oneshot tasks
    WD_STRETCH,             // Good for overrunning tasks
    WD_SLIP,                // Good for infinite loops
    WD_SUSPEND,                 // Good for most things
    WD_KILL                 // Death sentence
} wd_policy;

// Information about a misbehaving task
typedef struct bad_rt_task {
    RT_TASK     *task;      // Pointer to the bad task
    int          in_use;    // Allocated (static memory management)
    int          slipping;  // In the process of being slipped
    int          countdown; // Watchdog ticks to stay suspended
    int          count;     // How many times it's offended
    int          valid;     // Still an existing RT task
    int          forced;    // Forcibly suspended
    RTIME        orig_period;   // Original period before adjustments
    wd_policy        policy;    // Policy at time of last offence
    struct bad_rt_task  *next;      // Next in list
} BAD_RT_TASK;

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */

int __rtai_wd_init(void);

void __rtai_wd_exit(void);

// API for setting parameters
int rt_wdset_grace(int new_value);

int rt_wdset_gracediv(int new_value);

wd_policy rt_wdset_policy(wd_policy new_value);

int rt_wdset_slip(int new_value);

int rt_wdset_stretch(int new_value);

int rt_wdset_limit(int new_value);

int rt_wdset_safety(int new_value);

#ifdef __cplusplus
}
#endif /* __cplusplus */

#endif /* !_RTAI_WD_H */

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