Phabric: https://reviews.freebsd.org/D1247 Reviewed by: jhb, avg Sponsored by: Spectra Logic Corporation sys/kern_subr_taskqueue.c: Modify taskqueue_drain_all() processing to use a temporary "barrier task", rather than rely on a user task that may be destroyed during taskqueue_drain_all()'s execution. The barrier task is queued behind all previously queued tasks and then has its priority elevated so that future tasks cannot pass it in the queue. Use a similar barrier scheme to drain threads processing current tasks. This requires taskqueue_run_locked() to insert and remove the taskqueue_busy object for the running thread for every task processed. share/man/man9/taskqueue.9: Remove warning about live-lock issues with taskqueue_drain_all() and indicate that it does not wait for tasks queued after it begins processing.
794 lines
19 KiB
C
794 lines
19 KiB
C
/*-
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* Copyright (c) 2000 Doug Rabson
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/bus.h>
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#include <sys/cpuset.h>
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#include <sys/interrupt.h>
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#include <sys/kernel.h>
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#include <sys/kthread.h>
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#include <sys/limits.h>
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#include <sys/lock.h>
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#include <sys/malloc.h>
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#include <sys/mutex.h>
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#include <sys/proc.h>
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#include <sys/sched.h>
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#include <sys/taskqueue.h>
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#include <sys/unistd.h>
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#include <machine/stdarg.h>
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static MALLOC_DEFINE(M_TASKQUEUE, "taskqueue", "Task Queues");
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static void *taskqueue_giant_ih;
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static void *taskqueue_ih;
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static void taskqueue_fast_enqueue(void *);
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static void taskqueue_swi_enqueue(void *);
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static void taskqueue_swi_giant_enqueue(void *);
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struct taskqueue_busy {
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struct task *tb_running;
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TAILQ_ENTRY(taskqueue_busy) tb_link;
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};
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struct task * const TB_DRAIN_WAITER = (struct task *)0x1;
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struct taskqueue {
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STAILQ_HEAD(, task) tq_queue;
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taskqueue_enqueue_fn tq_enqueue;
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void *tq_context;
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TAILQ_HEAD(, taskqueue_busy) tq_active;
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struct mtx tq_mutex;
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struct thread **tq_threads;
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int tq_tcount;
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int tq_spin;
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int tq_flags;
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int tq_callouts;
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taskqueue_callback_fn tq_callbacks[TASKQUEUE_NUM_CALLBACKS];
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void *tq_cb_contexts[TASKQUEUE_NUM_CALLBACKS];
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};
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#define TQ_FLAGS_ACTIVE (1 << 0)
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#define TQ_FLAGS_BLOCKED (1 << 1)
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#define TQ_FLAGS_UNLOCKED_ENQUEUE (1 << 2)
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#define DT_CALLOUT_ARMED (1 << 0)
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#define TQ_LOCK(tq) \
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do { \
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if ((tq)->tq_spin) \
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mtx_lock_spin(&(tq)->tq_mutex); \
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else \
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mtx_lock(&(tq)->tq_mutex); \
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} while (0)
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#define TQ_ASSERT_LOCKED(tq) mtx_assert(&(tq)->tq_mutex, MA_OWNED)
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#define TQ_UNLOCK(tq) \
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do { \
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if ((tq)->tq_spin) \
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mtx_unlock_spin(&(tq)->tq_mutex); \
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else \
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mtx_unlock(&(tq)->tq_mutex); \
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} while (0)
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#define TQ_ASSERT_UNLOCKED(tq) mtx_assert(&(tq)->tq_mutex, MA_NOTOWNED)
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void
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_timeout_task_init(struct taskqueue *queue, struct timeout_task *timeout_task,
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int priority, task_fn_t func, void *context)
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{
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TASK_INIT(&timeout_task->t, priority, func, context);
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callout_init_mtx(&timeout_task->c, &queue->tq_mutex,
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CALLOUT_RETURNUNLOCKED);
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timeout_task->q = queue;
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timeout_task->f = 0;
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}
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static __inline int
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TQ_SLEEP(struct taskqueue *tq, void *p, struct mtx *m, int pri, const char *wm,
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int t)
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{
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if (tq->tq_spin)
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return (msleep_spin(p, m, wm, t));
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return (msleep(p, m, pri, wm, t));
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}
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static struct taskqueue *
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_taskqueue_create(const char *name __unused, int mflags,
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taskqueue_enqueue_fn enqueue, void *context,
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int mtxflags, const char *mtxname)
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{
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struct taskqueue *queue;
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queue = malloc(sizeof(struct taskqueue), M_TASKQUEUE, mflags | M_ZERO);
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if (!queue)
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return NULL;
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STAILQ_INIT(&queue->tq_queue);
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TAILQ_INIT(&queue->tq_active);
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queue->tq_enqueue = enqueue;
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queue->tq_context = context;
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queue->tq_spin = (mtxflags & MTX_SPIN) != 0;
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queue->tq_flags |= TQ_FLAGS_ACTIVE;
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if (enqueue == taskqueue_fast_enqueue ||
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enqueue == taskqueue_swi_enqueue ||
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enqueue == taskqueue_swi_giant_enqueue ||
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enqueue == taskqueue_thread_enqueue)
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queue->tq_flags |= TQ_FLAGS_UNLOCKED_ENQUEUE;
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mtx_init(&queue->tq_mutex, mtxname, NULL, mtxflags);
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return queue;
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}
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struct taskqueue *
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taskqueue_create(const char *name, int mflags,
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taskqueue_enqueue_fn enqueue, void *context)
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{
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return _taskqueue_create(name, mflags, enqueue, context,
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MTX_DEF, "taskqueue");
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}
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void
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taskqueue_set_callback(struct taskqueue *queue,
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enum taskqueue_callback_type cb_type, taskqueue_callback_fn callback,
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void *context)
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{
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KASSERT(((cb_type >= TASKQUEUE_CALLBACK_TYPE_MIN) &&
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(cb_type <= TASKQUEUE_CALLBACK_TYPE_MAX)),
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("Callback type %d not valid, must be %d-%d", cb_type,
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TASKQUEUE_CALLBACK_TYPE_MIN, TASKQUEUE_CALLBACK_TYPE_MAX));
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KASSERT((queue->tq_callbacks[cb_type] == NULL),
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("Re-initialization of taskqueue callback?"));
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queue->tq_callbacks[cb_type] = callback;
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queue->tq_cb_contexts[cb_type] = context;
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}
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/*
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* Signal a taskqueue thread to terminate.
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*/
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static void
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taskqueue_terminate(struct thread **pp, struct taskqueue *tq)
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{
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while (tq->tq_tcount > 0 || tq->tq_callouts > 0) {
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wakeup(tq);
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TQ_SLEEP(tq, pp, &tq->tq_mutex, PWAIT, "taskqueue_destroy", 0);
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}
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}
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void
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taskqueue_free(struct taskqueue *queue)
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{
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TQ_LOCK(queue);
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queue->tq_flags &= ~TQ_FLAGS_ACTIVE;
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taskqueue_terminate(queue->tq_threads, queue);
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KASSERT(TAILQ_EMPTY(&queue->tq_active), ("Tasks still running?"));
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KASSERT(queue->tq_callouts == 0, ("Armed timeout tasks"));
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mtx_destroy(&queue->tq_mutex);
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free(queue->tq_threads, M_TASKQUEUE);
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free(queue, M_TASKQUEUE);
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}
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static int
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taskqueue_enqueue_locked(struct taskqueue *queue, struct task *task)
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{
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struct task *ins;
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struct task *prev;
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/*
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* Count multiple enqueues.
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*/
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if (task->ta_pending) {
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if (task->ta_pending < USHRT_MAX)
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task->ta_pending++;
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TQ_UNLOCK(queue);
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return (0);
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}
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/*
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* Optimise the case when all tasks have the same priority.
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*/
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prev = STAILQ_LAST(&queue->tq_queue, task, ta_link);
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if (!prev || prev->ta_priority >= task->ta_priority) {
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STAILQ_INSERT_TAIL(&queue->tq_queue, task, ta_link);
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} else {
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prev = NULL;
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for (ins = STAILQ_FIRST(&queue->tq_queue); ins;
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prev = ins, ins = STAILQ_NEXT(ins, ta_link))
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if (ins->ta_priority < task->ta_priority)
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break;
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if (prev)
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STAILQ_INSERT_AFTER(&queue->tq_queue, prev, task, ta_link);
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else
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STAILQ_INSERT_HEAD(&queue->tq_queue, task, ta_link);
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}
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task->ta_pending = 1;
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if ((queue->tq_flags & TQ_FLAGS_UNLOCKED_ENQUEUE) != 0)
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TQ_UNLOCK(queue);
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if ((queue->tq_flags & TQ_FLAGS_BLOCKED) == 0)
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queue->tq_enqueue(queue->tq_context);
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if ((queue->tq_flags & TQ_FLAGS_UNLOCKED_ENQUEUE) == 0)
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TQ_UNLOCK(queue);
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/* Return with lock released. */
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return (0);
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}
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int
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taskqueue_enqueue(struct taskqueue *queue, struct task *task)
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{
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int res;
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TQ_LOCK(queue);
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res = taskqueue_enqueue_locked(queue, task);
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/* The lock is released inside. */
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return (res);
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}
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static void
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taskqueue_timeout_func(void *arg)
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{
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struct taskqueue *queue;
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struct timeout_task *timeout_task;
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timeout_task = arg;
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queue = timeout_task->q;
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KASSERT((timeout_task->f & DT_CALLOUT_ARMED) != 0, ("Stray timeout"));
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timeout_task->f &= ~DT_CALLOUT_ARMED;
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queue->tq_callouts--;
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taskqueue_enqueue_locked(timeout_task->q, &timeout_task->t);
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/* The lock is released inside. */
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}
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int
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taskqueue_enqueue_timeout(struct taskqueue *queue,
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struct timeout_task *timeout_task, int ticks)
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{
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int res;
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TQ_LOCK(queue);
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KASSERT(timeout_task->q == NULL || timeout_task->q == queue,
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("Migrated queue"));
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KASSERT(!queue->tq_spin, ("Timeout for spin-queue"));
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timeout_task->q = queue;
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res = timeout_task->t.ta_pending;
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if (ticks == 0) {
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taskqueue_enqueue_locked(queue, &timeout_task->t);
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/* The lock is released inside. */
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} else {
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if ((timeout_task->f & DT_CALLOUT_ARMED) != 0) {
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res++;
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} else {
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queue->tq_callouts++;
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timeout_task->f |= DT_CALLOUT_ARMED;
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if (ticks < 0)
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ticks = -ticks; /* Ignore overflow. */
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}
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if (ticks > 0) {
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callout_reset(&timeout_task->c, ticks,
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taskqueue_timeout_func, timeout_task);
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}
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TQ_UNLOCK(queue);
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}
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return (res);
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}
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static void
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taskqueue_task_nop_fn(void *context, int pending)
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{
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}
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/*
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* Block until all currently queued tasks in this taskqueue
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* have begun execution. Tasks queued during execution of
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* this function are ignored.
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*/
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static void
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taskqueue_drain_tq_queue(struct taskqueue *queue)
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{
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struct task t_barrier;
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if (STAILQ_EMPTY(&queue->tq_queue))
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return;
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/*
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* Enqueue our barrier with the lowest possible priority
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* so we are inserted after all current tasks.
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*/
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TASK_INIT(&t_barrier, 0, taskqueue_task_nop_fn, &t_barrier);
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taskqueue_enqueue_locked(queue, &t_barrier);
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/*
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* Raise the barrier's priority so newly queued tasks cannot
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* pass it.
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*/
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t_barrier.ta_priority = USHRT_MAX;
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/*
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* Once the barrier has executed, all previously queued tasks
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* have completed or are currently executing.
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*/
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while (t_barrier.ta_pending != 0)
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TQ_SLEEP(queue, &t_barrier, &queue->tq_mutex, PWAIT, "-", 0);
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}
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/*
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* Block until all currently executing tasks for this taskqueue
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* complete. Tasks that begin execution during the execution
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* of this function are ignored.
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*/
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static void
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taskqueue_drain_tq_active(struct taskqueue *queue)
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{
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struct taskqueue_busy tb_marker, *tb_first;
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if (TAILQ_EMPTY(&queue->tq_active))
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return;
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/* Block taskq_terminate().*/
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queue->tq_callouts++;
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/*
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* Wait for all currently executing taskqueue threads
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* to go idle.
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*/
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tb_marker.tb_running = TB_DRAIN_WAITER;
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TAILQ_INSERT_TAIL(&queue->tq_active, &tb_marker, tb_link);
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while (TAILQ_FIRST(&queue->tq_active) != &tb_marker)
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TQ_SLEEP(queue, &tb_marker, &queue->tq_mutex, PWAIT, "-", 0);
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TAILQ_REMOVE(&queue->tq_active, &tb_marker, tb_link);
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/*
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* Wakeup any other drain waiter that happened to queue up
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* without any intervening active thread.
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*/
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tb_first = TAILQ_FIRST(&queue->tq_active);
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if (tb_first != NULL && tb_first->tb_running == TB_DRAIN_WAITER)
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wakeup(tb_first);
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/* Release taskqueue_terminate(). */
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queue->tq_callouts--;
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if ((queue->tq_flags & TQ_FLAGS_ACTIVE) == 0)
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wakeup_one(queue->tq_threads);
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}
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void
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taskqueue_block(struct taskqueue *queue)
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{
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TQ_LOCK(queue);
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queue->tq_flags |= TQ_FLAGS_BLOCKED;
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TQ_UNLOCK(queue);
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}
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void
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taskqueue_unblock(struct taskqueue *queue)
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{
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TQ_LOCK(queue);
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queue->tq_flags &= ~TQ_FLAGS_BLOCKED;
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if (!STAILQ_EMPTY(&queue->tq_queue))
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queue->tq_enqueue(queue->tq_context);
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TQ_UNLOCK(queue);
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}
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static void
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taskqueue_run_locked(struct taskqueue *queue)
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{
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struct taskqueue_busy tb;
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struct taskqueue_busy *tb_first;
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struct task *task;
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int pending;
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TQ_ASSERT_LOCKED(queue);
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tb.tb_running = NULL;
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while (STAILQ_FIRST(&queue->tq_queue)) {
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TAILQ_INSERT_TAIL(&queue->tq_active, &tb, tb_link);
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/*
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* Carefully remove the first task from the queue and
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* zero its pending count.
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*/
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task = STAILQ_FIRST(&queue->tq_queue);
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STAILQ_REMOVE_HEAD(&queue->tq_queue, ta_link);
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pending = task->ta_pending;
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task->ta_pending = 0;
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tb.tb_running = task;
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TQ_UNLOCK(queue);
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task->ta_func(task->ta_context, pending);
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TQ_LOCK(queue);
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tb.tb_running = NULL;
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wakeup(task);
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TAILQ_REMOVE(&queue->tq_active, &tb, tb_link);
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tb_first = TAILQ_FIRST(&queue->tq_active);
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if (tb_first != NULL &&
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tb_first->tb_running == TB_DRAIN_WAITER)
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wakeup(tb_first);
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}
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}
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void
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taskqueue_run(struct taskqueue *queue)
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{
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TQ_LOCK(queue);
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taskqueue_run_locked(queue);
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TQ_UNLOCK(queue);
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}
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static int
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task_is_running(struct taskqueue *queue, struct task *task)
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{
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struct taskqueue_busy *tb;
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TQ_ASSERT_LOCKED(queue);
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TAILQ_FOREACH(tb, &queue->tq_active, tb_link) {
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if (tb->tb_running == task)
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return (1);
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}
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return (0);
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}
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static int
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taskqueue_cancel_locked(struct taskqueue *queue, struct task *task,
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u_int *pendp)
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{
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if (task->ta_pending > 0)
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STAILQ_REMOVE(&queue->tq_queue, task, task, ta_link);
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if (pendp != NULL)
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*pendp = task->ta_pending;
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task->ta_pending = 0;
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return (task_is_running(queue, task) ? EBUSY : 0);
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}
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int
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taskqueue_cancel(struct taskqueue *queue, struct task *task, u_int *pendp)
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{
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int error;
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TQ_LOCK(queue);
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error = taskqueue_cancel_locked(queue, task, pendp);
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TQ_UNLOCK(queue);
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return (error);
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}
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int
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taskqueue_cancel_timeout(struct taskqueue *queue,
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struct timeout_task *timeout_task, u_int *pendp)
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{
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u_int pending, pending1;
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int error;
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TQ_LOCK(queue);
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pending = !!callout_stop(&timeout_task->c);
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|
error = taskqueue_cancel_locked(queue, &timeout_task->t, &pending1);
|
|
if ((timeout_task->f & DT_CALLOUT_ARMED) != 0) {
|
|
timeout_task->f &= ~DT_CALLOUT_ARMED;
|
|
queue->tq_callouts--;
|
|
}
|
|
TQ_UNLOCK(queue);
|
|
|
|
if (pendp != NULL)
|
|
*pendp = pending + pending1;
|
|
return (error);
|
|
}
|
|
|
|
void
|
|
taskqueue_drain(struct taskqueue *queue, struct task *task)
|
|
{
|
|
|
|
if (!queue->tq_spin)
|
|
WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__);
|
|
|
|
TQ_LOCK(queue);
|
|
while (task->ta_pending != 0 || task_is_running(queue, task))
|
|
TQ_SLEEP(queue, task, &queue->tq_mutex, PWAIT, "-", 0);
|
|
TQ_UNLOCK(queue);
|
|
}
|
|
|
|
void
|
|
taskqueue_drain_all(struct taskqueue *queue)
|
|
{
|
|
|
|
if (!queue->tq_spin)
|
|
WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, __func__);
|
|
|
|
TQ_LOCK(queue);
|
|
taskqueue_drain_tq_queue(queue);
|
|
taskqueue_drain_tq_active(queue);
|
|
TQ_UNLOCK(queue);
|
|
}
|
|
|
|
void
|
|
taskqueue_drain_timeout(struct taskqueue *queue,
|
|
struct timeout_task *timeout_task)
|
|
{
|
|
|
|
callout_drain(&timeout_task->c);
|
|
taskqueue_drain(queue, &timeout_task->t);
|
|
}
|
|
|
|
static void
|
|
taskqueue_swi_enqueue(void *context)
|
|
{
|
|
swi_sched(taskqueue_ih, 0);
|
|
}
|
|
|
|
static void
|
|
taskqueue_swi_run(void *dummy)
|
|
{
|
|
taskqueue_run(taskqueue_swi);
|
|
}
|
|
|
|
static void
|
|
taskqueue_swi_giant_enqueue(void *context)
|
|
{
|
|
swi_sched(taskqueue_giant_ih, 0);
|
|
}
|
|
|
|
static void
|
|
taskqueue_swi_giant_run(void *dummy)
|
|
{
|
|
taskqueue_run(taskqueue_swi_giant);
|
|
}
|
|
|
|
static int
|
|
_taskqueue_start_threads(struct taskqueue **tqp, int count, int pri,
|
|
cpuset_t *mask, const char *ktname)
|
|
{
|
|
struct thread *td;
|
|
struct taskqueue *tq;
|
|
int i, error;
|
|
|
|
if (count <= 0)
|
|
return (EINVAL);
|
|
|
|
tq = *tqp;
|
|
|
|
tq->tq_threads = malloc(sizeof(struct thread *) * count, M_TASKQUEUE,
|
|
M_NOWAIT | M_ZERO);
|
|
if (tq->tq_threads == NULL) {
|
|
printf("%s: no memory for %s threads\n", __func__, ktname);
|
|
return (ENOMEM);
|
|
}
|
|
|
|
for (i = 0; i < count; i++) {
|
|
if (count == 1)
|
|
error = kthread_add(taskqueue_thread_loop, tqp, NULL,
|
|
&tq->tq_threads[i], RFSTOPPED, 0, "%s", ktname);
|
|
else
|
|
error = kthread_add(taskqueue_thread_loop, tqp, NULL,
|
|
&tq->tq_threads[i], RFSTOPPED, 0,
|
|
"%s_%d", ktname, i);
|
|
if (error) {
|
|
/* should be ok to continue, taskqueue_free will dtrt */
|
|
printf("%s: kthread_add(%s): error %d", __func__,
|
|
ktname, error);
|
|
tq->tq_threads[i] = NULL; /* paranoid */
|
|
} else
|
|
tq->tq_tcount++;
|
|
}
|
|
for (i = 0; i < count; i++) {
|
|
if (tq->tq_threads[i] == NULL)
|
|
continue;
|
|
td = tq->tq_threads[i];
|
|
if (mask) {
|
|
error = cpuset_setthread(td->td_tid, mask);
|
|
/*
|
|
* Failing to pin is rarely an actual fatal error;
|
|
* it'll just affect performance.
|
|
*/
|
|
if (error)
|
|
printf("%s: curthread=%llu: can't pin; "
|
|
"error=%d\n",
|
|
__func__,
|
|
(unsigned long long) td->td_tid,
|
|
error);
|
|
}
|
|
thread_lock(td);
|
|
sched_prio(td, pri);
|
|
sched_add(td, SRQ_BORING);
|
|
thread_unlock(td);
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
taskqueue_start_threads(struct taskqueue **tqp, int count, int pri,
|
|
const char *name, ...)
|
|
{
|
|
char ktname[MAXCOMLEN + 1];
|
|
va_list ap;
|
|
|
|
va_start(ap, name);
|
|
vsnprintf(ktname, sizeof(ktname), name, ap);
|
|
va_end(ap);
|
|
|
|
return (_taskqueue_start_threads(tqp, count, pri, NULL, ktname));
|
|
}
|
|
|
|
int
|
|
taskqueue_start_threads_pinned(struct taskqueue **tqp, int count, int pri,
|
|
int cpu_id, const char *name, ...)
|
|
{
|
|
char ktname[MAXCOMLEN + 1];
|
|
va_list ap;
|
|
cpuset_t mask;
|
|
|
|
va_start(ap, name);
|
|
vsnprintf(ktname, sizeof(ktname), name, ap);
|
|
va_end(ap);
|
|
|
|
/*
|
|
* In case someone passes in NOCPU, just fall back to the
|
|
* default behaviour of "don't pin".
|
|
*/
|
|
if (cpu_id != NOCPU) {
|
|
CPU_ZERO(&mask);
|
|
CPU_SET(cpu_id, &mask);
|
|
}
|
|
|
|
return (_taskqueue_start_threads(tqp, count, pri,
|
|
cpu_id == NOCPU ? NULL : &mask, ktname));
|
|
}
|
|
|
|
static inline void
|
|
taskqueue_run_callback(struct taskqueue *tq,
|
|
enum taskqueue_callback_type cb_type)
|
|
{
|
|
taskqueue_callback_fn tq_callback;
|
|
|
|
TQ_ASSERT_UNLOCKED(tq);
|
|
tq_callback = tq->tq_callbacks[cb_type];
|
|
if (tq_callback != NULL)
|
|
tq_callback(tq->tq_cb_contexts[cb_type]);
|
|
}
|
|
|
|
void
|
|
taskqueue_thread_loop(void *arg)
|
|
{
|
|
struct taskqueue **tqp, *tq;
|
|
|
|
tqp = arg;
|
|
tq = *tqp;
|
|
taskqueue_run_callback(tq, TASKQUEUE_CALLBACK_TYPE_INIT);
|
|
TQ_LOCK(tq);
|
|
while ((tq->tq_flags & TQ_FLAGS_ACTIVE) != 0) {
|
|
taskqueue_run_locked(tq);
|
|
/*
|
|
* Because taskqueue_run() can drop tq_mutex, we need to
|
|
* check if the TQ_FLAGS_ACTIVE flag wasn't removed in the
|
|
* meantime, which means we missed a wakeup.
|
|
*/
|
|
if ((tq->tq_flags & TQ_FLAGS_ACTIVE) == 0)
|
|
break;
|
|
TQ_SLEEP(tq, tq, &tq->tq_mutex, 0, "-", 0);
|
|
}
|
|
taskqueue_run_locked(tq);
|
|
|
|
/*
|
|
* This thread is on its way out, so just drop the lock temporarily
|
|
* in order to call the shutdown callback. This allows the callback
|
|
* to look at the taskqueue, even just before it dies.
|
|
*/
|
|
TQ_UNLOCK(tq);
|
|
taskqueue_run_callback(tq, TASKQUEUE_CALLBACK_TYPE_SHUTDOWN);
|
|
TQ_LOCK(tq);
|
|
|
|
/* rendezvous with thread that asked us to terminate */
|
|
tq->tq_tcount--;
|
|
wakeup_one(tq->tq_threads);
|
|
TQ_UNLOCK(tq);
|
|
kthread_exit();
|
|
}
|
|
|
|
void
|
|
taskqueue_thread_enqueue(void *context)
|
|
{
|
|
struct taskqueue **tqp, *tq;
|
|
|
|
tqp = context;
|
|
tq = *tqp;
|
|
|
|
wakeup_one(tq);
|
|
}
|
|
|
|
TASKQUEUE_DEFINE(swi, taskqueue_swi_enqueue, NULL,
|
|
swi_add(NULL, "task queue", taskqueue_swi_run, NULL, SWI_TQ,
|
|
INTR_MPSAFE, &taskqueue_ih));
|
|
|
|
TASKQUEUE_DEFINE(swi_giant, taskqueue_swi_giant_enqueue, NULL,
|
|
swi_add(NULL, "Giant taskq", taskqueue_swi_giant_run,
|
|
NULL, SWI_TQ_GIANT, 0, &taskqueue_giant_ih));
|
|
|
|
TASKQUEUE_DEFINE_THREAD(thread);
|
|
|
|
struct taskqueue *
|
|
taskqueue_create_fast(const char *name, int mflags,
|
|
taskqueue_enqueue_fn enqueue, void *context)
|
|
{
|
|
return _taskqueue_create(name, mflags, enqueue, context,
|
|
MTX_SPIN, "fast_taskqueue");
|
|
}
|
|
|
|
/* NB: for backwards compatibility */
|
|
int
|
|
taskqueue_enqueue_fast(struct taskqueue *queue, struct task *task)
|
|
{
|
|
return taskqueue_enqueue(queue, task);
|
|
}
|
|
|
|
static void *taskqueue_fast_ih;
|
|
|
|
static void
|
|
taskqueue_fast_enqueue(void *context)
|
|
{
|
|
swi_sched(taskqueue_fast_ih, 0);
|
|
}
|
|
|
|
static void
|
|
taskqueue_fast_run(void *dummy)
|
|
{
|
|
taskqueue_run(taskqueue_fast);
|
|
}
|
|
|
|
TASKQUEUE_FAST_DEFINE(fast, taskqueue_fast_enqueue, NULL,
|
|
swi_add(NULL, "fast taskq", taskqueue_fast_run, NULL,
|
|
SWI_TQ_FAST, INTR_MPSAFE, &taskqueue_fast_ih));
|
|
|
|
int
|
|
taskqueue_member(struct taskqueue *queue, struct thread *td)
|
|
{
|
|
int i, j, ret = 0;
|
|
|
|
for (i = 0, j = 0; ; i++) {
|
|
if (queue->tq_threads[i] == NULL)
|
|
continue;
|
|
if (queue->tq_threads[i] == td) {
|
|
ret = 1;
|
|
break;
|
|
}
|
|
if (++j >= queue->tq_tcount)
|
|
break;
|
|
}
|
|
return (ret);
|
|
}
|