freebsd-skq/sys/sys/callout.h
jkim 318c4f97e6 CALLOUT_MPSAFE has lost its meaning since r141428, i.e., for more than ten
years for head.  However, it is continuously misused as the mpsafe argument
for callout_init(9).  Deprecate the flag and clean up callout_init() calls
to make them more consistent.

Differential Revision:	https://reviews.freebsd.org/D2613
Reviewed by:	jhb
MFC after:	2 weeks
2015-05-22 17:05:21 +00:00

129 lines
6.1 KiB
C

/*-
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* 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.
* 4. 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 REGENTS 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 REGENTS 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.
*
* @(#)callout.h 8.2 (Berkeley) 1/21/94
* $FreeBSD$
*/
#ifndef _SYS_CALLOUT_H_
#define _SYS_CALLOUT_H_
#include <sys/_callout.h>
#define CALLOUT_LOCAL_ALLOC 0x0001 /* was allocated from callfree */
#define CALLOUT_ACTIVE 0x0002 /* callout is currently active */
#define CALLOUT_PENDING 0x0004 /* callout is waiting for timeout */
#define CALLOUT_MPSAFE 0x0008 /* deprecated */
#define CALLOUT_RETURNUNLOCKED 0x0010 /* handler returns with mtx unlocked */
#define CALLOUT_SHAREDLOCK 0x0020 /* callout lock held in shared mode */
#define CALLOUT_DFRMIGRATION 0x0040 /* callout in deferred migration mode */
#define CALLOUT_PROCESSED 0x0080 /* callout in wheel or processing list? */
#define CALLOUT_DIRECT 0x0100 /* allow exec from hw int context */
#define C_DIRECT_EXEC 0x0001 /* direct execution of callout */
#define C_PRELBITS 7
#define C_PRELRANGE ((1 << C_PRELBITS) - 1)
#define C_PREL(x) (((x) + 1) << 1)
#define C_PRELGET(x) (int)((((x) >> 1) & C_PRELRANGE) - 1)
#define C_HARDCLOCK 0x0100 /* align to hardclock() calls */
#define C_ABSOLUTE 0x0200 /* event time is absolute. */
struct callout_handle {
struct callout *callout;
};
#ifdef _KERNEL
/*
* Note the flags field is actually *two* fields. The c_flags
* field is the one that caller operations that may, or may not have
* a lock touches i.e. callout_deactivate(). The other, the c_iflags,
* is the internal flags that *must* be kept correct on which the
* callout system depend on e.g. callout_pending().
* The c_iflag is used internally by the callout system to determine which
* list the callout is on and track internal state. Callers *should not*
* use the c_flags field directly but should use the macros provided.
*
* The c_iflags field holds internal flags that are protected by internal
* locks of the callout subsystem. The c_flags field holds external flags.
* The caller must hold its own lock while manipulating or reading external
* flags via callout_active(), callout_deactivate(), callout_reset*(), or
* callout_stop() to avoid races.
*/
#define callout_active(c) ((c)->c_flags & CALLOUT_ACTIVE)
#define callout_deactivate(c) ((c)->c_flags &= ~CALLOUT_ACTIVE)
#define callout_drain(c) _callout_stop_safe(c, 1)
void callout_init(struct callout *, int);
void _callout_init_lock(struct callout *, struct lock_object *, int);
#define callout_init_mtx(c, mtx, flags) \
_callout_init_lock((c), ((mtx) != NULL) ? &(mtx)->lock_object : \
NULL, (flags))
#define callout_init_rm(c, rm, flags) \
_callout_init_lock((c), ((rm) != NULL) ? &(rm)->lock_object : \
NULL, (flags))
#define callout_init_rw(c, rw, flags) \
_callout_init_lock((c), ((rw) != NULL) ? &(rw)->lock_object : \
NULL, (flags))
#define callout_pending(c) ((c)->c_iflags & CALLOUT_PENDING)
int callout_reset_sbt_on(struct callout *, sbintime_t, sbintime_t,
void (*)(void *), void *, int, int);
#define callout_reset_sbt(c, sbt, pr, fn, arg, flags) \
callout_reset_sbt_on((c), (sbt), (pr), (fn), (arg), -1, (flags))
#define callout_reset_sbt_curcpu(c, sbt, pr, fn, arg, flags) \
callout_reset_sbt_on((c), (sbt), (pr), (fn), (arg), PCPU_GET(cpuid),\
(flags))
#define callout_reset_on(c, to_ticks, fn, arg, cpu) \
callout_reset_sbt_on((c), tick_sbt * (to_ticks), 0, (fn), (arg), \
(cpu), C_HARDCLOCK)
#define callout_reset(c, on_tick, fn, arg) \
callout_reset_on((c), (on_tick), (fn), (arg), -1)
#define callout_reset_curcpu(c, on_tick, fn, arg) \
callout_reset_on((c), (on_tick), (fn), (arg), PCPU_GET(cpuid))
#define callout_schedule_sbt_on(c, sbt, pr, cpu, flags) \
callout_reset_sbt_on((c), (sbt), (pr), (c)->c_func, (c)->c_arg, \
(cpu), (flags))
#define callout_schedule_sbt(c, sbt, pr, flags) \
callout_schedule_sbt_on((c), (sbt), (pr), -1, (flags))
#define callout_schedule_sbt_curcpu(c, sbt, pr, flags) \
callout_schedule_sbt_on((c), (sbt), (pr), PCPU_GET(cpuid), (flags))
int callout_schedule(struct callout *, int);
int callout_schedule_on(struct callout *, int, int);
#define callout_schedule_curcpu(c, on_tick) \
callout_schedule_on((c), (on_tick), PCPU_GET(cpuid))
#define callout_stop(c) _callout_stop_safe(c, 0)
int _callout_stop_safe(struct callout *, int);
void callout_process(sbintime_t now);
#endif
#endif /* _SYS_CALLOUT_H_ */