* idle window management
*/
struct timer_list idle_slice_timer;
- struct delayed_work unplug_work;
+ struct work_struct unplug_work;
struct cfq_queue *active_queue;
struct cfq_io_context *active_cic;
blk_add_trace_msg((cfqd)->queue, "cfq " fmt, ##args)
static void cfq_dispatch_insert(struct request_queue *, struct request *);
-static struct cfq_queue *cfq_get_queue(struct cfq_data *, int,
+static struct cfq_queue *cfq_get_queue(struct cfq_data *, bool,
struct io_context *, gfp_t);
static struct cfq_io_context *cfq_cic_lookup(struct cfq_data *,
struct io_context *);
}
static inline struct cfq_queue *cic_to_cfqq(struct cfq_io_context *cic,
- int is_sync)
+ bool is_sync)
{
- return cic->cfqq[!!is_sync];
+ return cic->cfqq[is_sync];
}
static inline void cic_set_cfqq(struct cfq_io_context *cic,
- struct cfq_queue *cfqq, int is_sync)
+ struct cfq_queue *cfqq, bool is_sync)
{
- cic->cfqq[!!is_sync] = cfqq;
+ cic->cfqq[is_sync] = cfqq;
}
/*
* We regard a request as SYNC, if it's either a read or has the SYNC bit
* set (in which case it could also be direct WRITE).
*/
-static inline int cfq_bio_sync(struct bio *bio)
+static inline bool cfq_bio_sync(struct bio *bio)
{
- if (bio_data_dir(bio) == READ || bio_rw_flagged(bio, BIO_RW_SYNCIO))
- return 1;
-
- return 0;
+ return bio_data_dir(bio) == READ || bio_rw_flagged(bio, BIO_RW_SYNCIO);
}
/*
* scheduler run of queue, if there are requests pending and no one in the
* driver that will restart queueing
*/
-static inline void cfq_schedule_dispatch(struct cfq_data *cfqd,
- unsigned long delay)
+static inline void cfq_schedule_dispatch(struct cfq_data *cfqd)
{
if (cfqd->busy_queues) {
cfq_log(cfqd, "schedule dispatch");
- kblockd_schedule_delayed_work(cfqd->queue, &cfqd->unplug_work,
- delay);
+ kblockd_schedule_work(cfqd->queue, &cfqd->unplug_work);
}
}
* if a queue is marked sync and has sync io queued. A sync queue with async
* io only, should not get full sync slice length.
*/
-static inline int cfq_prio_slice(struct cfq_data *cfqd, int sync,
+static inline int cfq_prio_slice(struct cfq_data *cfqd, bool sync,
unsigned short prio)
{
const int base_slice = cfqd->cfq_slice[sync];
* isn't valid until the first request from the dispatch is activated
* and the slice time set.
*/
-static inline int cfq_slice_used(struct cfq_queue *cfqq)
+static inline bool cfq_slice_used(struct cfq_queue *cfqq)
{
if (cfq_cfqq_slice_new(cfqq))
return 0;
* we will service the queues.
*/
static void cfq_service_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq,
- int add_front)
+ bool add_front)
{
struct rb_node **p, *parent;
struct cfq_queue *__cfqq;
} else
rb_key += jiffies;
} else if (!add_front) {
+ /*
+ * Get our rb key offset. Subtract any residual slice
+ * value carried from last service. A negative resid
+ * count indicates slice overrun, and this should position
+ * the next service time further away in the tree.
+ */
rb_key = cfq_slice_offset(cfqd, cfqq) + jiffies;
- rb_key += cfqq->slice_resid;
+ rb_key -= cfqq->slice_resid;
cfqq->slice_resid = 0;
- } else
- rb_key = 0;
+ } else {
+ rb_key = -HZ;
+ __cfqq = cfq_rb_first(&cfqd->service_tree);
+ rb_key += __cfqq ? __cfqq->rb_key : jiffies;
+ }
if (!RB_EMPTY_NODE(&cfqq->rb_node)) {
/*
n = &(*p)->rb_left;
else if (cfq_class_idle(cfqq) > cfq_class_idle(__cfqq))
n = &(*p)->rb_right;
- else if (rb_key < __cfqq->rb_key)
+ else if (time_before(rb_key, __cfqq->rb_key))
n = &(*p)->rb_left;
else
n = &(*p)->rb_right;
* Disallow merge of a sync bio into an async request.
*/
if (cfq_bio_sync(bio) && !rq_is_sync(rq))
- return 0;
+ return false;
/*
* Lookup the cfqq that this bio will be queued with. Allow
*/
cic = cfq_cic_lookup(cfqd, current->io_context);
if (!cic)
- return 0;
+ return false;
cfqq = cic_to_cfqq(cic, cfq_bio_sync(bio));
- if (cfqq == RQ_CFQQ(rq))
- return 1;
-
- return 0;
+ return cfqq == RQ_CFQQ(rq);
}
static void __cfq_set_active_queue(struct cfq_data *cfqd,
*/
static void
__cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq,
- int timed_out)
+ bool timed_out)
{
cfq_log_cfqq(cfqd, cfqq, "slice expired t=%d", timed_out);
}
}
-static inline void cfq_slice_expired(struct cfq_data *cfqd, int timed_out)
+static inline void cfq_slice_expired(struct cfq_data *cfqd, bool timed_out)
{
struct cfq_queue *cfqq = cfqd->active_queue;
*/
static struct cfq_queue *cfq_close_cooperator(struct cfq_data *cfqd,
struct cfq_queue *cur_cfqq,
- int probe)
+ bool probe)
{
struct cfq_queue *cfqq;
if (!cic || !atomic_read(&cic->ioc->nr_tasks))
return;
+ /*
+ * If our average think time is larger than the remaining time
+ * slice, then don't idle. This avoids overrunning the allotted
+ * time slice.
+ */
+ if (sample_valid(cic->ttime_samples) &&
+ (cfqq->slice_end - jiffies < cic->ttime_mean))
+ return;
+
cfq_mark_cfqq_wait_request(cfqq);
/*
return dispatched;
}
-/*
- * Dispatch a request from cfqq, moving them to the request queue
- * dispatch list.
- */
-static void cfq_dispatch_request(struct cfq_data *cfqd, struct cfq_queue *cfqq)
+static bool cfq_may_dispatch(struct cfq_data *cfqd, struct cfq_queue *cfqq)
{
- struct request *rq;
-
- BUG_ON(RB_EMPTY_ROOT(&cfqq->sort_list));
-
- /*
- * follow expired path, else get first next available
- */
- rq = cfq_check_fifo(cfqq);
- if (!rq)
- rq = cfqq->next_rq;
-
- /*
- * insert request into driver dispatch list
- */
- cfq_dispatch_insert(cfqd->queue, rq);
-
- if (!cfqd->active_cic) {
- struct cfq_io_context *cic = RQ_CIC(rq);
-
- atomic_long_inc(&cic->ioc->refcount);
- cfqd->active_cic = cic;
- }
-}
-
-/*
- * Find the cfqq that we need to service and move a request from that to the
- * dispatch list
- */
-static int cfq_dispatch_requests(struct request_queue *q, int force)
-{
- struct cfq_data *cfqd = q->elevator->elevator_data;
- struct cfq_queue *cfqq;
unsigned int max_dispatch;
- if (!cfqd->busy_queues)
- return 0;
-
- if (unlikely(force))
- return cfq_forced_dispatch(cfqd);
-
- cfqq = cfq_select_queue(cfqd);
- if (!cfqq)
- return 0;
-
/*
* Drain async requests before we start sync IO
*/
if (cfq_cfqq_idle_window(cfqq) && cfqd->rq_in_driver[BLK_RW_ASYNC])
- return 0;
+ return false;
/*
* If this is an async queue and we have sync IO in flight, let it wait
*/
if (cfqd->sync_flight && !cfq_cfqq_sync(cfqq))
- return 0;
+ return false;
max_dispatch = cfqd->cfq_quantum;
if (cfq_class_idle(cfqq))
* idle queue must always only have a single IO in flight
*/
if (cfq_class_idle(cfqq))
- return 0;
+ return false;
/*
* We have other queues, don't allow more IO from this one
*/
if (cfqd->busy_queues > 1)
- return 0;
+ return false;
/*
* Sole queue user, allow bigger slice
max_dispatch = depth;
}
- if (cfqq->dispatched >= max_dispatch)
+ /*
+ * If we're below the current max, allow a dispatch
+ */
+ return cfqq->dispatched < max_dispatch;
+}
+
+/*
+ * Dispatch a request from cfqq, moving them to the request queue
+ * dispatch list.
+ */
+static bool cfq_dispatch_request(struct cfq_data *cfqd, struct cfq_queue *cfqq)
+{
+ struct request *rq;
+
+ BUG_ON(RB_EMPTY_ROOT(&cfqq->sort_list));
+
+ if (!cfq_may_dispatch(cfqd, cfqq))
+ return false;
+
+ /*
+ * follow expired path, else get first next available
+ */
+ rq = cfq_check_fifo(cfqq);
+ if (!rq)
+ rq = cfqq->next_rq;
+
+ /*
+ * insert request into driver dispatch list
+ */
+ cfq_dispatch_insert(cfqd->queue, rq);
+
+ if (!cfqd->active_cic) {
+ struct cfq_io_context *cic = RQ_CIC(rq);
+
+ atomic_long_inc(&cic->ioc->refcount);
+ cfqd->active_cic = cic;
+ }
+
+ return true;
+}
+
+/*
+ * Find the cfqq that we need to service and move a request from that to the
+ * dispatch list
+ */
+static int cfq_dispatch_requests(struct request_queue *q, int force)
+{
+ struct cfq_data *cfqd = q->elevator->elevator_data;
+ struct cfq_queue *cfqq;
+
+ if (!cfqd->busy_queues)
+ return 0;
+
+ if (unlikely(force))
+ return cfq_forced_dispatch(cfqd);
+
+ cfqq = cfq_select_queue(cfqd);
+ if (!cfqq)
return 0;
/*
- * Dispatch a request from this cfqq
+ * Dispatch a request from this cfqq, if it is allowed
*/
- cfq_dispatch_request(cfqd, cfqq);
+ if (!cfq_dispatch_request(cfqd, cfqq))
+ return 0;
+
cfqq->slice_dispatch++;
cfq_clear_cfqq_must_dispatch(cfqq);
if (unlikely(cfqd->active_queue == cfqq)) {
__cfq_slice_expired(cfqd, cfqq, 0);
- cfq_schedule_dispatch(cfqd, 0);
+ cfq_schedule_dispatch(cfqd);
}
kmem_cache_free(cfq_pool, cfqq);
{
if (unlikely(cfqq == cfqd->active_queue)) {
__cfq_slice_expired(cfqd, cfqq, 0);
- cfq_schedule_dispatch(cfqd, 0);
+ cfq_schedule_dispatch(cfqd);
}
cfq_put_queue(cfqq);
}
static void cfq_init_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq,
- pid_t pid, int is_sync)
+ pid_t pid, bool is_sync)
{
RB_CLEAR_NODE(&cfqq->rb_node);
RB_CLEAR_NODE(&cfqq->p_node);
}
static struct cfq_queue *
-cfq_find_alloc_queue(struct cfq_data *cfqd, int is_sync,
+cfq_find_alloc_queue(struct cfq_data *cfqd, bool is_sync,
struct io_context *ioc, gfp_t gfp_mask)
{
struct cfq_queue *cfqq, *new_cfqq = NULL;
}
static struct cfq_queue *
-cfq_get_queue(struct cfq_data *cfqd, int is_sync, struct io_context *ioc,
+cfq_get_queue(struct cfq_data *cfqd, bool is_sync, struct io_context *ioc,
gfp_t gfp_mask)
{
const int ioprio = task_ioprio(ioc);
(!cfqd->cfq_latency && cfqd->hw_tag && CIC_SEEKY(cic)))
enable_idle = 0;
else if (sample_valid(cic->ttime_samples)) {
- if (cic->ttime_mean > cfqd->cfq_slice_idle)
+ unsigned int slice_idle = cfqd->cfq_slice_idle;
+ if (sample_valid(cic->seek_samples) && CIC_SEEKY(cic))
+ slice_idle = msecs_to_jiffies(CFQ_MIN_TT);
+ if (cic->ttime_mean > slice_idle)
enable_idle = 0;
else
enable_idle = 1;
* Check if new_cfqq should preempt the currently active queue. Return 0 for
* no or if we aren't sure, a 1 will cause a preempt.
*/
-static int
+static bool
cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
struct request *rq)
{
cfqq = cfqd->active_queue;
if (!cfqq)
- return 0;
+ return false;
if (cfq_slice_used(cfqq))
- return 1;
+ return true;
if (cfq_class_idle(new_cfqq))
- return 0;
+ return false;
if (cfq_class_idle(cfqq))
- return 1;
+ return true;
/*
* if the new request is sync, but the currently running queue is
* not, let the sync request have priority.
*/
if (rq_is_sync(rq) && !cfq_cfqq_sync(cfqq))
- return 1;
+ return true;
/*
* So both queues are sync. Let the new request get disk time if
* it's a metadata request and the current queue is doing regular IO.
*/
if (rq_is_meta(rq) && !cfqq->meta_pending)
- return 1;
+ return false;
/*
* Allow an RT request to pre-empt an ongoing non-RT cfqq timeslice.
*/
if (cfq_class_rt(new_cfqq) && !cfq_class_rt(cfqq))
- return 1;
+ return true;
if (!cfqd->active_cic || !cfq_cfqq_wait_request(cfqq))
- return 0;
+ return false;
/*
* if this request is as-good as one we would expect from the
* current cfqq, let it preempt
*/
if (cfq_rq_close(cfqd, rq))
- return 1;
+ return true;
- return 0;
+ return false;
}
/*
}
if (!rq_in_driver(cfqd))
- cfq_schedule_dispatch(cfqd, 0);
+ cfq_schedule_dispatch(cfqd);
}
/*
struct cfq_data *cfqd = q->elevator->elevator_data;
struct cfq_io_context *cic;
const int rw = rq_data_dir(rq);
- const int is_sync = rq_is_sync(rq);
+ const bool is_sync = rq_is_sync(rq);
struct cfq_queue *cfqq;
unsigned long flags;
if (cic)
put_io_context(cic->ioc);
- cfq_schedule_dispatch(cfqd, 0);
+ cfq_schedule_dispatch(cfqd);
spin_unlock_irqrestore(q->queue_lock, flags);
cfq_log(cfqd, "set_request fail");
return 1;
static void cfq_kick_queue(struct work_struct *work)
{
struct cfq_data *cfqd =
- container_of(work, struct cfq_data, unplug_work.work);
+ container_of(work, struct cfq_data, unplug_work);
struct request_queue *q = cfqd->queue;
spin_lock_irq(q->queue_lock);
expire:
cfq_slice_expired(cfqd, timed_out);
out_kick:
- cfq_schedule_dispatch(cfqd, 0);
+ cfq_schedule_dispatch(cfqd);
out_cont:
spin_unlock_irqrestore(cfqd->queue->queue_lock, flags);
}
static void cfq_shutdown_timer_wq(struct cfq_data *cfqd)
{
del_timer_sync(&cfqd->idle_slice_timer);
- cancel_delayed_work_sync(&cfqd->unplug_work);
+ cancel_work_sync(&cfqd->unplug_work);
}
static void cfq_put_async_queues(struct cfq_data *cfqd)
cfqd->idle_slice_timer.function = cfq_idle_slice_timer;
cfqd->idle_slice_timer.data = (unsigned long) cfqd;
- INIT_DELAYED_WORK(&cfqd->unplug_work, cfq_kick_queue);
+ INIT_WORK(&cfqd->unplug_work, cfq_kick_queue);
cfqd->cfq_quantum = cfq_quantum;
cfqd->cfq_fifo_expire[0] = cfq_fifo_expire[0];
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff