freebsd-skq/sys/sys/_task.h
zml f1e0737c28 Revert r207439 and solve the problem differently. The task handler
ta_func may free the task structure, so no references to its members
are valid after the handler has been called. Using a per-queue member
and having waits longer than strictly necessary was suggested by jhb.

Submitted by:       Matthew Fleming <matthew.fleming@isilon.com>
Reviewed by:        zml, jhb
2010-05-28 18:15:28 +00:00

55 lines
2.1 KiB
C

/*-
* Copyright (c) 2000 Doug Rabson
* All rights reserved.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* $FreeBSD$
*/
#ifndef _SYS__TASK_H_
#define _SYS__TASK_H_
#include <sys/queue.h>
/*
* Each task includes a function which is called from
* taskqueue_run(). The first argument is taken from the 'ta_context'
* field of struct task and the second argument is a count of how many
* times the task was enqueued before the call to taskqueue_run().
*
* List of locks
* (c) const after init
* (q) taskqueue lock
*/
typedef void task_fn_t(void *context, int pending);
struct task {
STAILQ_ENTRY(task) ta_link; /* (q) link for queue */
u_short ta_pending; /* (q) count times queued */
u_short ta_priority; /* (c) Priority */
task_fn_t *ta_func; /* (c) task handler */
void *ta_context; /* (c) argument for handler */
};
#endif /* !_SYS__TASK_H_ */