freebsd-dev/sys/cddl/compat/opensolaris/kern/opensolaris_taskq.c
Pawel Jakub Dawidek 541c60d988 Don't access task structure once we call task function.
The task structure might be no longer available.
This also allows to eliminates the need for two tasks in the zio structure.

Submitted by:	anonymous
MFC after:	2 weeks
2011-05-24 20:07:15 +00:00

173 lines
4.4 KiB
C

/*-
* Copyright (c) 2009 Pawel Jakub Dawidek <pjd@FreeBSD.org>
* 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 AUTHORS 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 AUTHORS 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/kmem.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/queue.h>
#include <sys/taskqueue.h>
#include <sys/taskq.h>
#include <vm/uma.h>
static uma_zone_t taskq_zone;
taskq_t *system_taskq = NULL;
static void
system_taskq_init(void *arg)
{
taskq_zone = uma_zcreate("taskq_zone", sizeof(struct ostask),
NULL, NULL, NULL, NULL, 0, 0);
system_taskq = taskq_create("system_taskq", mp_ncpus, 0, 0, 0, 0);
}
SYSINIT(system_taskq_init, SI_SUB_CONFIGURE, SI_ORDER_ANY, system_taskq_init, NULL);
static void
system_taskq_fini(void *arg)
{
taskq_destroy(system_taskq);
uma_zdestroy(taskq_zone);
}
SYSUNINIT(system_taskq_fini, SI_SUB_CONFIGURE, SI_ORDER_ANY, system_taskq_fini, NULL);
taskq_t *
taskq_create(const char *name, int nthreads, pri_t pri, int minalloc __unused,
int maxalloc __unused, uint_t flags)
{
taskq_t *tq;
if ((flags & TASKQ_THREADS_CPU_PCT) != 0)
nthreads = MAX((mp_ncpus * nthreads) / 100, 1);
tq = kmem_alloc(sizeof(*tq), KM_SLEEP);
tq->tq_queue = taskqueue_create(name, M_WAITOK, taskqueue_thread_enqueue,
&tq->tq_queue);
(void) taskqueue_start_threads(&tq->tq_queue, nthreads, pri, "%s", name);
return ((taskq_t *)tq);
}
taskq_t *
taskq_create_proc(const char *name, int nthreads, pri_t pri, int minalloc,
int maxalloc, proc_t *proc __unused, uint_t flags)
{
return (taskq_create(name, nthreads, pri, minalloc, maxalloc, flags));
}
void
taskq_destroy(taskq_t *tq)
{
taskqueue_free(tq->tq_queue);
kmem_free(tq, sizeof(*tq));
}
int
taskq_member(taskq_t *tq, kthread_t *thread)
{
return (taskqueue_member(tq->tq_queue, thread));
}
static void
taskq_run(void *arg, int pending __unused)
{
struct ostask *task = arg;
task->ost_func(task->ost_arg);
uma_zfree(taskq_zone, task);
}
taskqid_t
taskq_dispatch(taskq_t *tq, task_func_t func, void *arg, uint_t flags)
{
struct ostask *task;
int mflag, prio;
if ((flags & (TQ_SLEEP | TQ_NOQUEUE)) == TQ_SLEEP)
mflag = M_WAITOK;
else
mflag = M_NOWAIT;
/*
* If TQ_FRONT is given, we want higher priority for this task, so it
* can go at the front of the queue.
*/
prio = !!(flags & TQ_FRONT);
task = uma_zalloc(taskq_zone, mflag);
if (task == NULL)
return (0);
task->ost_func = func;
task->ost_arg = arg;
TASK_INIT(&task->ost_task, prio, taskq_run, task);
taskqueue_enqueue(tq->tq_queue, &task->ost_task);
return ((taskqid_t)(void *)task);
}
#define TASKQ_MAGIC 0x74541c
static void
taskq_run_safe(void *arg, int pending __unused)
{
struct ostask *task = arg;
task->ost_func(task->ost_arg);
}
taskqid_t
taskq_dispatch_safe(taskq_t *tq, task_func_t func, void *arg, u_int flags,
struct ostask *task)
{
int prio;
/*
* If TQ_FRONT is given, we want higher priority for this task, so it
* can go at the front of the queue.
*/
prio = !!(flags & TQ_FRONT);
task->ost_func = func;
task->ost_arg = arg;
TASK_INIT(&task->ost_task, prio, taskq_run_safe, task);
taskqueue_enqueue(tq->tq_queue, &task->ost_task);
return ((taskqid_t)(void *)task);
}