1/*	$NetBSD: callout.h,v 1.32 2015/02/07 19:36:42 christos Exp $	*/
  2
  3/*-
  4 * Copyright (c) 2000, 2003, 2006, 2007, 2008 The NetBSD Foundation, Inc.
  5 * All rights reserved.
  6 *
  7 * This code is derived from software contributed to The NetBSD Foundation
  8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
  9 * NASA Ames Research Center, and by Andrew Doran.
 10 *
 11 * Redistribution and use in source and binary forms, with or without
 12 * modification, are permitted provided that the following conditions
 13 * are met:
 14 * 1. Redistributions of source code must retain the above copyright
 15 *    notice, this list of conditions and the following disclaimer.
 16 * 2. Redistributions in binary form must reproduce the above copyright
 17 *    notice, this list of conditions and the following disclaimer in the
 18 *    documentation and/or other materials provided with the distribution.
 19 *
 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 23 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 30 * POSSIBILITY OF SUCH DAMAGE.
 31 */
 32
 33#ifndef _SYS_CALLOUT_H_
 34#define _SYS_CALLOUT_H_
 35
 36#include <sys/types.h>
 37
 38/*
 39 * The callout implementation is private to kern_timeout.c yet uses
 40 * caller-supplied storage, as lightweight callout operations are
 41 * critical to system performance.
 42 *
 43 * The size of callout_t must remain constant in order to ensure ABI
 44 * compatibility for kernel modules: it may become smaller, but must
 45 * not grow.  If more space is required, rearrange the members of
 46 * callout_impl_t.
 47 */
 48typedef struct callout {
 49	void	*_c_store[10];
 50} callout_t;
 51
 52/* Internal flags. */
 53#define	CALLOUT_BOUND		0x0001	/* bound to a specific CPU */
 54#define	CALLOUT_PENDING		0x0002	/* callout is on the queue */
 55#define	CALLOUT_FIRED		0x0004	/* callout has fired */
 56#define	CALLOUT_INVOKING	0x0008	/* callout function is being invoked */
 57
 58/* End-user flags. */
 59#define	CALLOUT_MPSAFE		0x0100	/* does not need kernel_lock */
 60#define	CALLOUT_FLAGMASK	0xff00
 61
 62#define CALLOUT_FMT	"\177\020\
 63b\00BOUND\0\
 64b\01PENDING\0\
 65b\02FIRED\0\
 66b\03INVOKING\0\
 67b\10MPSAFE\0"
 68
 69#ifdef _CALLOUT_PRIVATE
 70
 71/* The following funkyness is to appease gcc3's strict aliasing. */
 72struct callout_circq {
 73	/* next element */
 74	union {
 75		struct callout_impl	*elem;
 76		struct callout_circq	*list;
 77	} cq_next;
 78	/* previous element */
 79	union {
 80		struct callout_impl	*elem;
 81		struct callout_circq	*list;
 82	} cq_prev;
 83};
 84#define	cq_next_e	cq_next.elem
 85#define	cq_prev_e	cq_prev.elem
 86#define	cq_next_l	cq_next.list
 87#define	cq_prev_l	cq_prev.list
 88
 89struct callout_cpu;
 90
 91typedef struct callout_impl {
 92	struct callout_circq c_list;		/* linkage on queue */
 93	void	(*c_func)(void *);		/* function to call */
 94	void	*c_arg;				/* function argument */
 95	struct callout_cpu * volatile c_cpu;	/* associated CPU */
 96	int	c_time;				/* when callout fires */
 97	u_int	c_flags;			/* state of this entry */
 98	u_int	c_magic;			/* magic number */
 99} callout_impl_t;
100#define	CALLOUT_MAGIC		0x11deeba1
101
102#endif	/* _CALLOUT_PRIVATE */
103
104#ifdef _KERNEL
105struct cpu_info;
106
107void	callout_startup(void);
108void	callout_init_cpu(struct cpu_info *);
109void	callout_hardclock(void);
110
111void	callout_init(callout_t *, u_int);
112void	callout_destroy(callout_t *);
113void	callout_setfunc(callout_t *, void (*)(void *), void *);
114void	callout_reset(callout_t *, int, void (*)(void *), void *);
115void	callout_schedule(callout_t *, int);
116bool	callout_stop(callout_t *);
117bool	callout_halt(callout_t *, void *);
118bool	callout_pending(callout_t *);
119bool	callout_expired(callout_t *);
120bool	callout_active(callout_t *);
121bool	callout_invoking(callout_t *);
122void	callout_ack(callout_t *);
123void	callout_bind(callout_t *, struct cpu_info *);
124#endif	/* _KERNEL */
125
126#endif /* !_SYS_CALLOUT_H_ */