os161/kern/include/hangman.h
2017-02-09 09:49:03 -05:00

85 lines
2.9 KiB
C

/*
* Copyright (c) 2015
* The President and Fellows of Harvard College.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE UNIVERSITY AND CONTRIBUTORS ``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 UNIVERSITY OR CONTRIBUTORS 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.
*/
#ifndef HANGMAN_H
#define HANGMAN_H
/*
* Simple deadlock detector. Enable with "options hangman" in the
* kernel config.
*/
#include "opt-hangman.h"
#if OPT_HANGMAN
struct hangman_actor {
const char *a_name;
const struct hangman_lockable *a_waiting;
};
struct hangman_lockable {
const char *l_name;
const struct hangman_actor *l_holding;
};
void hangman_wait(struct hangman_actor *a, struct hangman_lockable *l);
void hangman_acquire(struct hangman_actor *a, struct hangman_lockable *l);
void hangman_release(struct hangman_actor *a, struct hangman_lockable *l);
#define HANGMAN_ACTOR(sym) struct hangman_actor sym
#define HANGMAN_LOCKABLE(sym) struct hangman_lockable sym
#define HANGMAN_ACTORINIT(a, n) ((a)->a_name = (n), (a)->a_waiting = NULL)
#define HANGMAN_LOCKABLEINIT(l, n) ((l)->l_name = (n), (l)->l_holding = NULL)
#define HANGMAN_LOCKABLE_INITIALIZER { "spinlock", NULL }
#define HANGMAN_WAIT(a, l) hangman_wait(a, l)
#define HANGMAN_ACQUIRE(a, l) hangman_acquire(a, l)
#define HANGMAN_RELEASE(a, l) hangman_release(a, l)
#else
#define HANGMAN_ACTOR(sym)
#define HANGMAN_LOCKABLE(sym)
#define HANGMAN_ACTORINIT(a, name)
#define HANGMAN_LOCKABLEINIT(a, name)
#define HANGMAN_LOCKABLE_INITIALIZER
#define HANGMAN_WAIT(a, l)
#define HANGMAN_ACQUIRE(a, l)
#define HANGMAN_RELEASE(a, l)
#endif
#endif /* HANGMAN_H */