xref: /freebsd/sys/sys/callout.h (revision efcb2ec8cb81ea44c58e41082c6d965f9493099f)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1990, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * (c) UNIX System Laboratories, Inc.
7  * All or some portions of this file are derived from material licensed
8  * to the University of California by American Telephone and Telegraph
9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10  * the permission of UNIX System Laboratories, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef _SYS_CALLOUT_H_
38 #define _SYS_CALLOUT_H_
39 
40 #include <sys/_callout.h>
41 
42 #define	CALLOUT_TRYLOCK		0x0001 /* try semantic in softclock_call_cc */
43 #define	CALLOUT_ACTIVE		0x0002 /* callout is currently active */
44 #define	CALLOUT_PENDING		0x0004 /* callout is waiting for timeout */
45 #define	CALLOUT_MPSAFE		0x0008 /* deprecated */
46 #define	CALLOUT_RETURNUNLOCKED	0x0010 /* handler returns with mtx unlocked */
47 #define	CALLOUT_SHAREDLOCK	0x0020 /* callout lock held in shared mode */
48 #define	CALLOUT_DFRMIGRATION	0x0040 /* callout in deferred migration mode */
49 #define	CALLOUT_PROCESSED	0x0080 /* callout in wheel or processing list? */
50 #define	CALLOUT_DIRECT 		0x0100 /* allow exec from hw int context */
51 
52 #define	C_DIRECT_EXEC		0x0001 /* direct execution of callout */
53 #define	C_PRELBITS		7
54 #define	C_PRELRANGE		((1 << C_PRELBITS) - 1)
55 #define	C_PREL(x)		(((x) + 1) << 1)
56 #define	C_PRELGET(x)		(int)((((x) >> 1) & C_PRELRANGE) - 1)
57 #define	C_HARDCLOCK		0x0100 /* align to hardclock() calls */
58 #define	C_ABSOLUTE		0x0200 /* event time is absolute. */
59 #define	C_PRECALC		0x0400 /* event time is pre-calculated. */
60 #define	C_CATCH			0x0800 /* catch signals, used by pause_sbt(9) */
61 
62 /* Flags for callout_stop_safe() */
63 #define	CS_DRAIN		0x0001 /* callout_drain(), wait allowed */
64 
65 #ifdef _KERNEL
66 /*
67  * Note the flags field is actually *two* fields. The c_flags
68  * field is the one that caller operations that may, or may not have
69  * a lock touches i.e. callout_deactivate(). The other, the c_iflags,
70  * is the internal flags that *must* be kept correct on which the
71  * callout system depend on e.g. callout_pending().
72  * The c_iflag is used internally by the callout system to determine which
73  * list the callout is on and track internal state. Callers *should not*
74  * use the c_flags field directly but should use the macros provided.
75  *
76  * The c_iflags field holds internal flags that are protected by internal
77  * locks of the callout subsystem.  The c_flags field holds external flags.
78  * The caller must hold its own lock while manipulating or reading external
79  * flags via callout_active(), callout_deactivate(), callout_reset*(), or
80  * callout_stop() to avoid races.
81  */
82 #define	callout_active(c)	((c)->c_flags & CALLOUT_ACTIVE)
83 #define	callout_deactivate(c)	((c)->c_flags &= ~CALLOUT_ACTIVE)
84 #define	callout_drain(c)	_callout_stop_safe(c, CS_DRAIN)
85 void	callout_init(struct callout *, int);
86 void	_callout_init_lock(struct callout *, struct lock_object *, int);
87 #define	callout_init_mtx(c, mtx, flags)					\
88 	_callout_init_lock((c), &(mtx)->lock_object, (flags))
89 #define	callout_init_rm(c, rm, flags)					\
90 	_callout_init_lock((c), &(rm)->lock_object, (flags))
91 #define	callout_init_rw(c, rw, flags)					\
92 	_callout_init_lock((c), &(rw)->lock_object, (flags))
93 #define	callout_pending(c)	((c)->c_iflags & CALLOUT_PENDING)
94 int	callout_reset_sbt_on(struct callout *, sbintime_t, sbintime_t,
95 	    void (*)(void *), void *, int, int);
96 #define	callout_reset_sbt(c, sbt, pr, fn, arg, flags)			\
97     callout_reset_sbt_on((c), (sbt), (pr), (fn), (arg), -1, (flags))
98 #define	callout_reset_sbt_curcpu(c, sbt, pr, fn, arg, flags)		\
99     callout_reset_sbt_on((c), (sbt), (pr), (fn), (arg), PCPU_GET(cpuid),\
100         (flags))
101 #define	callout_reset_on(c, to_ticks, fn, arg, cpu)			\
102     callout_reset_sbt_on((c), tick_sbt * (to_ticks), 0, (fn), (arg),	\
103         (cpu), C_HARDCLOCK)
104 #define	callout_reset(c, on_tick, fn, arg)				\
105     callout_reset_on((c), (on_tick), (fn), (arg), -1)
106 #define	callout_reset_curcpu(c, on_tick, fn, arg)			\
107     callout_reset_on((c), (on_tick), (fn), (arg), PCPU_GET(cpuid))
108 #define	callout_schedule_sbt_on(c, sbt, pr, cpu, flags)			\
109     callout_reset_sbt_on((c), (sbt), (pr), (c)->c_func, (c)->c_arg,	\
110         (cpu), (flags))
111 #define	callout_schedule_sbt(c, sbt, pr, flags)				\
112     callout_schedule_sbt_on((c), (sbt), (pr), -1, (flags))
113 #define	callout_schedule_sbt_curcpu(c, sbt, pr, flags)			\
114     callout_schedule_sbt_on((c), (sbt), (pr), PCPU_GET(cpuid), (flags))
115 int	callout_schedule(struct callout *, int);
116 int	callout_schedule_on(struct callout *, int, int);
117 #define	callout_schedule_curcpu(c, on_tick)				\
118     callout_schedule_on((c), (on_tick), PCPU_GET(cpuid))
119 #define	callout_stop(c)		_callout_stop_safe(c, 0)
120 int	_callout_stop_safe(struct callout *, int);
121 void	callout_process(sbintime_t now);
122 void callout_when(sbintime_t sbt, sbintime_t precision, int flags,
123     sbintime_t *sbt_res, sbintime_t *prec_res);
124 #endif
125 
126 #endif /* _SYS_CALLOUT_H_ */
127