[PATCH] CFQ io scheduler updates
- Adjust slice values
- Instead of one async queue, one is defined per priority level. This
prevents kernel threads (such as reiserfs/x and others) that run at
higher io priority from conflicting with others. Previously, it was a
coin toss what io prio the async queue got, it was defined by who
first set up the queue.
- Let a time slice only begin, when the previous slice is completely
done. Previously we could be somewhat unfair to a new sync slice, if
the previous slice was async and had several ios queued. This might
need a little tweaking if throughput suffers a little due to this,
allowing perhaps an overlap of a single request or so.
- Optimize the calling of kblockd_schedule_work() by doing it only when
it is strictly necessary (no requests in driver and work left to do).
- Correct sync vs async logic. A 'normal' process can be purely async as
well, and a flusher can be purely sync as well. Sync or async is now a
property of the class defined and requests pending. Previously writers
could be considered sync, when they were really async.
- Get rid of the bit fields in cfqq and crq, use flags instead.
- Various other cleanups and fixes
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/block/cfq-iosched.c b/drivers/block/cfq-iosched.c
index baa3e26..1ecb179 100644
--- a/drivers/block/cfq-iosched.c
+++ b/drivers/block/cfq-iosched.c
@@ -34,14 +34,15 @@
static int cfq_back_penalty = 2; /* penalty of a backwards seek */
static int cfq_slice_sync = HZ / 10;
-static int cfq_slice_async = HZ / 50;
+static int cfq_slice_async = HZ / 25;
static int cfq_slice_async_rq = 2;
-static int cfq_slice_idle = HZ / 50;
+static int cfq_slice_idle = HZ / 100;
#define CFQ_IDLE_GRACE (HZ / 10)
#define CFQ_SLICE_SCALE (5)
#define CFQ_KEY_ASYNC (0)
+#define CFQ_KEY_ANY (0xffff)
/*
* disable queueing at the driver/hardware level
@@ -96,7 +97,16 @@
#define cfq_class_be(cfqq) ((cfqq)->ioprio_class == IOPRIO_CLASS_BE)
#define cfq_class_rt(cfqq) ((cfqq)->ioprio_class == IOPRIO_CLASS_RT)
-#define cfq_cfqq_sync(cfqq) ((cfqq)->key != CFQ_KEY_ASYNC)
+#define ASYNC (0)
+#define SYNC (1)
+
+#define cfq_cfqq_dispatched(cfqq) \
+ ((cfqq)->on_dispatch[ASYNC] + (cfqq)->on_dispatch[SYNC])
+
+#define cfq_cfqq_class_sync(cfqq) ((cfqq)->key != CFQ_KEY_ASYNC)
+
+#define cfq_cfqq_sync(cfqq) \
+ (cfq_cfqq_class_sync(cfqq) || (cfqq)->on_dispatch[SYNC])
/*
* Per block device queue structure
@@ -200,28 +210,15 @@
unsigned long slice_left;
unsigned long service_last;
- /* number of requests that have been handed to the driver */
- int in_flight;
+ /* number of requests that are on the dispatch list */
+ int on_dispatch[2];
/* io prio of this group */
unsigned short ioprio, org_ioprio;
unsigned short ioprio_class, org_ioprio_class;
- /* whether queue is on rr (or empty) list */
- unsigned on_rr : 1;
- /* idle slice, waiting for new request submission */
- unsigned wait_request : 1;
- /* set when wait_request gets set, reset on first rq alloc */
- unsigned must_alloc : 1;
- /* only gets one must_alloc per slice */
- unsigned must_alloc_slice : 1;
- /* idle slice, request added, now waiting to dispatch it */
- unsigned must_dispatch : 1;
- /* fifo expire per-slice */
- unsigned fifo_expire : 1;
-
- unsigned idle_window : 1;
- unsigned prio_changed : 1;
+ /* various state flags, see below */
+ unsigned int flags;
};
struct cfq_rq {
@@ -233,15 +230,77 @@
struct cfq_queue *cfq_queue;
struct cfq_io_context *io_context;
- unsigned in_flight : 1;
- unsigned accounted : 1;
- unsigned is_sync : 1;
- unsigned requeued : 1;
+ unsigned int crq_flags;
};
-static struct cfq_queue *cfq_find_cfq_hash(struct cfq_data *, unsigned int);
+enum cfqq_state_flags {
+ CFQ_CFQQ_FLAG_on_rr = 0,
+ CFQ_CFQQ_FLAG_wait_request,
+ CFQ_CFQQ_FLAG_must_alloc,
+ CFQ_CFQQ_FLAG_must_alloc_slice,
+ CFQ_CFQQ_FLAG_must_dispatch,
+ CFQ_CFQQ_FLAG_fifo_expire,
+ CFQ_CFQQ_FLAG_idle_window,
+ CFQ_CFQQ_FLAG_prio_changed,
+ CFQ_CFQQ_FLAG_expired,
+};
+
+#define CFQ_CFQQ_FNS(name) \
+static inline void cfq_mark_cfqq_##name(struct cfq_queue *cfqq) \
+{ \
+ cfqq->flags |= (1 << CFQ_CFQQ_FLAG_##name); \
+} \
+static inline void cfq_clear_cfqq_##name(struct cfq_queue *cfqq) \
+{ \
+ cfqq->flags &= ~(1 << CFQ_CFQQ_FLAG_##name); \
+} \
+static inline int cfq_cfqq_##name(const struct cfq_queue *cfqq) \
+{ \
+ return (cfqq->flags & (1 << CFQ_CFQQ_FLAG_##name)) != 0; \
+}
+
+CFQ_CFQQ_FNS(on_rr);
+CFQ_CFQQ_FNS(wait_request);
+CFQ_CFQQ_FNS(must_alloc);
+CFQ_CFQQ_FNS(must_alloc_slice);
+CFQ_CFQQ_FNS(must_dispatch);
+CFQ_CFQQ_FNS(fifo_expire);
+CFQ_CFQQ_FNS(idle_window);
+CFQ_CFQQ_FNS(prio_changed);
+CFQ_CFQQ_FNS(expired);
+#undef CFQ_CFQQ_FNS
+
+enum cfq_rq_state_flags {
+ CFQ_CRQ_FLAG_in_flight = 0,
+ CFQ_CRQ_FLAG_in_driver,
+ CFQ_CRQ_FLAG_is_sync,
+ CFQ_CRQ_FLAG_requeued,
+};
+
+#define CFQ_CRQ_FNS(name) \
+static inline void cfq_mark_crq_##name(struct cfq_rq *crq) \
+{ \
+ crq->crq_flags |= (1 << CFQ_CRQ_FLAG_##name); \
+} \
+static inline void cfq_clear_crq_##name(struct cfq_rq *crq) \
+{ \
+ crq->crq_flags &= ~(1 << CFQ_CRQ_FLAG_##name); \
+} \
+static inline int cfq_crq_##name(const struct cfq_rq *crq) \
+{ \
+ return (crq->crq_flags & (1 << CFQ_CRQ_FLAG_##name)) != 0; \
+}
+
+CFQ_CRQ_FNS(in_flight);
+CFQ_CRQ_FNS(in_driver);
+CFQ_CRQ_FNS(is_sync);
+CFQ_CRQ_FNS(requeued);
+#undef CFQ_CRQ_FNS
+
+static struct cfq_queue *cfq_find_cfq_hash(struct cfq_data *, unsigned int, unsigned short);
static void cfq_dispatch_sort(request_queue_t *, struct cfq_rq *);
static void cfq_put_cfqd(struct cfq_data *cfqd);
+static inline int cfq_pending_requests(struct cfq_data *cfqd);
#define process_sync(tsk) ((tsk)->flags & PF_SYNCWRITE)
@@ -305,9 +364,9 @@
return crq2;
if (crq2 == NULL)
return crq1;
- if (crq1->requeued)
+ if (cfq_crq_requeued(crq1))
return crq1;
- if (crq2->requeued)
+ if (cfq_crq_requeued(crq2))
return crq2;
s1 = crq1->request->sector;
@@ -407,7 +466,7 @@
struct cfq_data *cfqd = cfqq->cfqd;
struct list_head *list, *entry;
- BUG_ON(!cfqq->on_rr);
+ BUG_ON(!cfq_cfqq_on_rr(cfqq));
list_del(&cfqq->cfq_list);
@@ -423,7 +482,7 @@
* has lots of io pending vs one that only generates one
* sporadically or synchronously
*/
- if (cfqq->in_flight)
+ if (cfq_cfqq_dispatched(cfqq))
list = &cfqd->busy_rr;
else
list = &cfqd->rr_list[cfqq->ioprio];
@@ -461,8 +520,8 @@
static inline void
cfq_add_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq, int requeue)
{
- BUG_ON(cfqq->on_rr);
- cfqq->on_rr = 1;
+ BUG_ON(cfq_cfqq_on_rr(cfqq));
+ cfq_mark_cfqq_on_rr(cfqq);
cfqd->busy_queues++;
cfq_resort_rr_list(cfqq, requeue);
@@ -471,8 +530,8 @@
static inline void
cfq_del_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq)
{
- BUG_ON(!cfqq->on_rr);
- cfqq->on_rr = 0;
+ BUG_ON(!cfq_cfqq_on_rr(cfqq));
+ cfq_clear_cfqq_on_rr(cfqq);
list_move(&cfqq->cfq_list, &cfqd->empty_list);
BUG_ON(!cfqd->busy_queues);
@@ -488,7 +547,7 @@
if (ON_RB(&crq->rb_node)) {
struct cfq_data *cfqd = cfqq->cfqd;
- const int sync = crq->is_sync;
+ const int sync = cfq_crq_is_sync(crq);
BUG_ON(!cfqq->queued[sync]);
cfqq->queued[sync]--;
@@ -498,7 +557,7 @@
rb_erase(&crq->rb_node, &cfqq->sort_list);
RB_CLEAR_COLOR(&crq->rb_node);
- if (cfqq->on_rr && RB_EMPTY(&cfqq->sort_list))
+ if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY(&cfqq->sort_list))
cfq_del_cfqq_rr(cfqd, cfqq);
}
}
@@ -534,7 +593,7 @@
struct cfq_rq *__alias;
crq->rb_key = rq_rb_key(rq);
- cfqq->queued[crq->is_sync]++;
+ cfqq->queued[cfq_crq_is_sync(crq)]++;
/*
* looks a little odd, but the first insert might return an alias.
@@ -545,8 +604,8 @@
rb_insert_color(&crq->rb_node, &cfqq->sort_list);
- if (!cfqq->on_rr)
- cfq_add_cfqq_rr(cfqd, cfqq, crq->requeued);
+ if (!cfq_cfqq_on_rr(cfqq))
+ cfq_add_cfqq_rr(cfqd, cfqq, cfq_crq_requeued(crq));
/*
* check if this request is a better next-serve candidate
@@ -559,7 +618,7 @@
{
if (ON_RB(&crq->rb_node)) {
rb_erase(&crq->rb_node, &cfqq->sort_list);
- cfqq->queued[crq->is_sync]--;
+ cfqq->queued[cfq_crq_is_sync(crq)]--;
}
cfq_add_crq_rb(crq);
@@ -568,7 +627,7 @@
static struct request *cfq_find_rq_rb(struct cfq_data *cfqd, sector_t sector)
{
- struct cfq_queue *cfqq = cfq_find_cfq_hash(cfqd, current->pid);
+ struct cfq_queue *cfqq = cfq_find_cfq_hash(cfqd, current->pid, CFQ_KEY_ANY);
struct rb_node *n;
if (!cfqq)
@@ -598,17 +657,19 @@
if (crq) {
struct cfq_queue *cfqq = crq->cfq_queue;
- if (crq->accounted) {
- crq->accounted = 0;
+ if (cfq_crq_in_driver(crq)) {
+ cfq_clear_crq_in_driver(crq);
WARN_ON(!cfqd->rq_in_driver);
cfqd->rq_in_driver--;
}
- if (crq->in_flight) {
- crq->in_flight = 0;
- WARN_ON(!cfqq->in_flight);
- cfqq->in_flight--;
+ if (cfq_crq_in_flight(crq)) {
+ const int sync = cfq_crq_is_sync(crq);
+
+ cfq_clear_crq_in_flight(crq);
+ WARN_ON(!cfqq->on_dispatch[sync]);
+ cfqq->on_dispatch[sync]--;
}
- crq->requeued = 1;
+ cfq_mark_crq_requeued(crq);
}
}
@@ -712,8 +773,9 @@
cfqq->slice_start = jiffies;
cfqq->slice_end = 0;
cfqq->slice_left = 0;
- cfqq->must_alloc_slice = 0;
- cfqq->fifo_expire = 0;
+ cfq_clear_cfqq_must_alloc_slice(cfqq);
+ cfq_clear_cfqq_fifo_expire(cfqq);
+ cfq_clear_cfqq_expired(cfqq);
}
cfqd->active_queue = cfqq;
@@ -776,9 +838,18 @@
return prio;
}
-static void cfq_set_active_queue(struct cfq_data *cfqd)
+static struct cfq_queue *cfq_set_active_queue(struct cfq_data *cfqd)
{
- struct cfq_queue *cfqq = NULL;
+ struct cfq_queue *cfqq;
+
+ /*
+ * if current queue is expired but not done with its requests yet,
+ * wait for that to happen
+ */
+ if ((cfqq = cfqd->active_queue) != NULL) {
+ if (cfq_cfqq_expired(cfqq) && cfq_cfqq_dispatched(cfqq))
+ return NULL;
+ }
/*
* if current list is non-empty, grab first entry. if it is empty,
@@ -802,48 +873,64 @@
}
__cfq_set_active_queue(cfqd, cfqq);
+ return cfqq;
}
/*
* current cfqq expired its slice (or was too idle), select new one
*/
+static void
+__cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq,
+ int preempted)
+{
+ unsigned long now = jiffies;
+
+ if (cfq_cfqq_wait_request(cfqq))
+ del_timer(&cfqd->idle_slice_timer);
+
+ if (!preempted && !cfq_cfqq_dispatched(cfqq))
+ cfqq->service_last = now;
+
+ cfq_clear_cfqq_must_dispatch(cfqq);
+ cfq_clear_cfqq_wait_request(cfqq);
+
+ /*
+ * store what was left of this slice, if the queue idled out
+ * or was preempted
+ */
+ if (time_after(now, cfqq->slice_end))
+ cfqq->slice_left = now - cfqq->slice_end;
+ else
+ cfqq->slice_left = 0;
+
+ if (cfq_cfqq_on_rr(cfqq))
+ cfq_resort_rr_list(cfqq, preempted);
+
+ if (cfqq == cfqd->active_queue)
+ cfqd->active_queue = NULL;
+
+ if (cfqd->active_cic) {
+ put_io_context(cfqd->active_cic->ioc);
+ cfqd->active_cic = NULL;
+ }
+
+ cfqd->dispatch_slice = 0;
+}
+
static inline void cfq_slice_expired(struct cfq_data *cfqd, int preempted)
{
struct cfq_queue *cfqq = cfqd->active_queue;
if (cfqq) {
- unsigned long now = jiffies;
-
- if (cfqq->wait_request)
- del_timer(&cfqd->idle_slice_timer);
-
- if (!preempted && !cfqq->in_flight)
- cfqq->service_last = now;
-
- cfqq->must_dispatch = 0;
- cfqq->wait_request = 0;
-
/*
- * store what was left of this slice, if the queue idled out
- * or was preempted
+ * use deferred expiry, if there are requests in progress as
+ * not to disturb the slice of the next queue
*/
- if (time_after(now, cfqq->slice_end))
- cfqq->slice_left = now - cfqq->slice_end;
+ if (cfq_cfqq_dispatched(cfqq))
+ cfq_mark_cfqq_expired(cfqq);
else
- cfqq->slice_left = 0;
-
- if (cfqq->on_rr)
- cfq_resort_rr_list(cfqq, preempted);
-
- cfqd->active_queue = NULL;
-
- if (cfqd->active_cic) {
- put_io_context(cfqd->active_cic->ioc);
- cfqd->active_cic = NULL;
- }
+ __cfq_slice_expired(cfqd, cfqq, preempted);
}
-
- cfqd->dispatch_slice = 0;
}
static int cfq_arm_slice_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq)
@@ -857,7 +944,7 @@
*/
if (!cfqd->cfq_slice_idle)
return 0;
- if (!cfqq->idle_window)
+ if (!cfq_cfqq_idle_window(cfqq))
return 0;
/*
* task has exited, don't wait
@@ -865,13 +952,13 @@
if (cfqd->active_cic && !cfqd->active_cic->ioc->task)
return 0;
- cfqq->wait_request = 1;
- cfqq->must_alloc = 1;
+ cfq_mark_cfqq_must_dispatch(cfqq);
+ cfq_mark_cfqq_wait_request(cfqq);
if (!timer_pending(&cfqd->idle_slice_timer)) {
- unsigned long slice_left = cfqq->slice_end - 1;
+ unsigned long slice_left = min(cfqq->slice_end - 1, (unsigned long) cfqd->cfq_slice_idle);
- cfqd->idle_slice_timer.expires = min(jiffies + cfqd->cfq_slice_idle, slice_left);
+ cfqd->idle_slice_timer.expires = jiffies + slice_left;
add_timer(&cfqd->idle_slice_timer);
}
@@ -901,7 +988,7 @@
break;
if (!blk_fs_request(__rq))
break;
- if (__crq->requeued)
+ if (cfq_crq_requeued(__crq))
break;
if (__rq->sector <= crq->request->sector)
@@ -920,9 +1007,10 @@
cfq_del_crq_rb(crq);
cfq_remove_merge_hints(q, crq);
- crq->in_flight = 1;
- crq->requeued = 0;
- cfqq->in_flight++;
+ cfq_mark_crq_in_flight(crq);
+ cfq_clear_crq_requeued(crq);
+
+ cfqq->on_dispatch[cfq_crq_is_sync(crq)]++;
list_add_tail(&crq->request->queuelist, entry);
}
@@ -935,16 +1023,16 @@
struct request *rq;
struct cfq_rq *crq;
- if (cfqq->fifo_expire)
+ if (cfq_cfqq_fifo_expire(cfqq))
return NULL;
if (!list_empty(&cfqq->fifo)) {
- int fifo = cfq_cfqq_sync(cfqq);
+ int fifo = cfq_cfqq_class_sync(cfqq);
crq = RQ_DATA(list_entry_fifo(cfqq->fifo.next));
rq = crq->request;
if (time_after(jiffies, rq->start_time + cfqd->cfq_fifo_expire[fifo])) {
- cfqq->fifo_expire = 1;
+ cfq_mark_cfqq_fifo_expire(cfqq);
return crq;
}
}
@@ -953,7 +1041,9 @@
}
/*
- * Scale schedule slice based on io priority
+ * Scale schedule slice based on io priority. Use the sync time slice only
+ * 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_to_slice(struct cfq_data *cfqd, struct cfq_queue *cfqq)
@@ -982,6 +1072,16 @@
}
/*
+ * 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)
+{
+ if (!cfqd->rq_in_driver && cfq_pending_requests(cfqd))
+ kblockd_schedule_work(&cfqd->unplug_work);
+}
+
+/*
* get next queue for service
*/
static struct cfq_queue *cfq_select_queue(struct cfq_data *cfqd, int force)
@@ -993,11 +1093,14 @@
if (!cfqq)
goto new_queue;
+ if (cfq_cfqq_expired(cfqq))
+ goto new_queue;
+
/*
* slice has expired
*/
- if (!cfqq->must_dispatch && time_after(jiffies, cfqq->slice_end))
- goto new_queue;
+ if (!cfq_cfqq_must_dispatch(cfqq) && time_after(now, cfqq->slice_end))
+ goto expire;
/*
* if queue has requests, dispatch one. if not, check if
@@ -1005,17 +1108,18 @@
*/
if (!RB_EMPTY(&cfqq->sort_list))
goto keep_queue;
- else if (!force && cfq_cfqq_sync(cfqq) &&
+ else if (!force && cfq_cfqq_class_sync(cfqq) &&
time_before(now, cfqq->slice_end)) {
if (cfq_arm_slice_timer(cfqd, cfqq))
return NULL;
}
-new_queue:
+expire:
cfq_slice_expired(cfqd, 0);
- cfq_set_active_queue(cfqd);
+new_queue:
+ cfqq = cfq_set_active_queue(cfqd);
keep_queue:
- return cfqd->active_queue;
+ return cfqq;
}
static int
@@ -1083,8 +1187,8 @@
cfqq = cfq_select_queue(cfqd, force);
if (cfqq) {
- cfqq->wait_request = 0;
- cfqq->must_dispatch = 0;
+ cfq_clear_cfqq_must_dispatch(cfqq);
+ cfq_clear_cfqq_wait_request(cfqq);
del_timer(&cfqd->idle_slice_timer);
if (cfq_class_idle(cfqq))
@@ -1108,10 +1212,10 @@
* accounted bit is necessary since some drivers will call
* elv_next_request() many times for the same request (eg ide)
*/
- if (crq->accounted)
+ if (cfq_crq_in_driver(crq))
return;
- crq->accounted = 1;
+ cfq_mark_crq_in_driver(crq);
cfqd->rq_in_driver++;
}
@@ -1121,7 +1225,7 @@
struct cfq_data *cfqd = cfqq->cfqd;
unsigned long now;
- if (!crq->accounted)
+ if (!cfq_crq_in_driver(crq))
return;
now = jiffies;
@@ -1132,12 +1236,18 @@
if (!cfq_class_idle(cfqq))
cfqd->last_end_request = now;
- if (!cfqq->in_flight && cfqq->on_rr) {
- cfqq->service_last = now;
- cfq_resort_rr_list(cfqq, 0);
+ if (!cfq_cfqq_dispatched(cfqq)) {
+ if (cfq_cfqq_on_rr(cfqq)) {
+ cfqq->service_last = now;
+ cfq_resort_rr_list(cfqq, 0);
+ }
+ if (cfq_cfqq_expired(cfqq)) {
+ __cfq_slice_expired(cfqd, cfqq, 0);
+ cfq_schedule_dispatch(cfqd);
+ }
}
- if (crq->is_sync)
+ if (cfq_crq_is_sync(crq))
crq->io_context->last_end_request = now;
}
@@ -1153,10 +1263,13 @@
crq = RQ_DATA(rq);
if (crq) {
+ struct cfq_queue *cfqq = crq->cfq_queue;
+
/*
* if idle window is disabled, allow queue buildup
*/
- if (!crq->in_flight && !crq->cfq_queue->idle_window &&
+ if (!cfq_crq_in_driver(crq) &&
+ !cfq_cfqq_idle_window(cfqq) &&
cfqd->rq_in_driver >= cfqd->cfq_max_depth)
return NULL;
@@ -1190,11 +1303,11 @@
BUG_ON(rb_first(&cfqq->sort_list));
BUG_ON(cfqq->allocated[READ] + cfqq->allocated[WRITE]);
- BUG_ON(cfqq->on_rr);
+ BUG_ON(cfq_cfqq_on_rr(cfqq));
if (unlikely(cfqd->active_queue == cfqq)) {
- cfq_slice_expired(cfqd, 0);
- kblockd_schedule_work(&cfqd->unplug_work);
+ __cfq_slice_expired(cfqd, cfqq, 0);
+ cfq_schedule_dispatch(cfqd);
}
cfq_put_cfqd(cfqq->cfqd);
@@ -1208,15 +1321,17 @@
}
static inline struct cfq_queue *
-__cfq_find_cfq_hash(struct cfq_data *cfqd, unsigned int key, const int hashval)
+__cfq_find_cfq_hash(struct cfq_data *cfqd, unsigned int key, unsigned int prio,
+ const int hashval)
{
struct hlist_head *hash_list = &cfqd->cfq_hash[hashval];
struct hlist_node *entry, *next;
hlist_for_each_safe(entry, next, hash_list) {
struct cfq_queue *__cfqq = list_entry_qhash(entry);
+ const unsigned short __p = IOPRIO_PRIO_VALUE(__cfqq->ioprio_class, __cfqq->ioprio);
- if (__cfqq->key == key)
+ if (__cfqq->key == key && (__p == prio || prio == CFQ_KEY_ANY))
return __cfqq;
}
@@ -1224,9 +1339,9 @@
}
static struct cfq_queue *
-cfq_find_cfq_hash(struct cfq_data *cfqd, unsigned int key)
+cfq_find_cfq_hash(struct cfq_data *cfqd, unsigned int key, unsigned short prio)
{
- return __cfq_find_cfq_hash(cfqd, key, hash_long(key, CFQ_QHASH_SHIFT));
+ return __cfq_find_cfq_hash(cfqd, key, prio, hash_long(key, CFQ_QHASH_SHIFT));
}
static void cfq_free_io_context(struct cfq_io_context *cic)
@@ -1255,8 +1370,8 @@
spin_lock(q->queue_lock);
if (unlikely(cic->cfqq == cfqd->active_queue)) {
- cfq_slice_expired(cfqd, 0);
- kblockd_schedule_work(&cfqd->unplug_work);
+ __cfq_slice_expired(cfqd, cic->cfqq, 0);
+ cfq_schedule_dispatch(cfqd);
}
cfq_put_queue(cic->cfqq);
@@ -1313,7 +1428,7 @@
struct task_struct *tsk = current;
int ioprio_class;
- if (!cfqq->prio_changed)
+ if (!cfq_cfqq_prio_changed(cfqq))
return;
ioprio_class = IOPRIO_PRIO_CLASS(tsk->ioprio);
@@ -1338,7 +1453,7 @@
case IOPRIO_CLASS_IDLE:
cfqq->ioprio_class = IOPRIO_CLASS_IDLE;
cfqq->ioprio = 7;
- cfqq->idle_window = 0;
+ cfq_clear_cfqq_idle_window(cfqq);
break;
}
@@ -1349,10 +1464,10 @@
cfqq->org_ioprio = cfqq->ioprio;
cfqq->org_ioprio_class = cfqq->ioprio_class;
- if (cfqq->on_rr)
+ if (cfq_cfqq_on_rr(cfqq))
cfq_resort_rr_list(cfqq, 0);
- cfqq->prio_changed = 0;
+ cfq_clear_cfqq_prio_changed(cfqq);
}
static inline void changed_ioprio(struct cfq_queue *cfqq)
@@ -1361,7 +1476,7 @@
struct cfq_data *cfqd = cfqq->cfqd;
spin_lock(cfqd->queue->queue_lock);
- cfqq->prio_changed = 1;
+ cfq_mark_cfqq_prio_changed(cfqq);
cfq_init_prio_data(cfqq);
spin_unlock(cfqd->queue->queue_lock);
}
@@ -1383,13 +1498,14 @@
}
static struct cfq_queue *
-cfq_get_queue(struct cfq_data *cfqd, unsigned int key, int gfp_mask)
+cfq_get_queue(struct cfq_data *cfqd, unsigned int key, unsigned short ioprio,
+ int gfp_mask)
{
const int hashval = hash_long(key, CFQ_QHASH_SHIFT);
struct cfq_queue *cfqq, *new_cfqq = NULL;
retry:
- cfqq = __cfq_find_cfq_hash(cfqd, key, hashval);
+ cfqq = __cfq_find_cfq_hash(cfqd, key, ioprio, hashval);
if (!cfqq) {
if (new_cfqq) {
@@ -1423,10 +1539,9 @@
* set ->slice_left to allow preemption for a new process
*/
cfqq->slice_left = 2 * cfqd->cfq_slice_idle;
- cfqq->idle_window = 1;
- cfqq->ioprio = -1;
- cfqq->ioprio_class = -1;
- cfqq->prio_changed = 1;
+ cfq_mark_cfqq_idle_window(cfqq);
+ cfq_mark_cfqq_prio_changed(cfqq);
+ cfq_init_prio_data(cfqq);
}
if (new_cfqq)
@@ -1553,7 +1668,7 @@
cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq,
struct cfq_io_context *cic)
{
- int enable_idle = cfqq->idle_window;
+ int enable_idle = cfq_cfqq_idle_window(cfqq);
if (!cic->ioc->task || !cfqd->cfq_slice_idle)
enable_idle = 0;
@@ -1564,7 +1679,10 @@
enable_idle = 1;
}
- cfqq->idle_window = enable_idle;
+ if (enable_idle)
+ cfq_mark_cfqq_idle_window(cfqq);
+ else
+ cfq_clear_cfqq_idle_window(cfqq);
}
@@ -1586,14 +1704,14 @@
if (cfq_class_idle(cfqq))
return 1;
- if (!new_cfqq->wait_request)
+ if (!cfq_cfqq_wait_request(new_cfqq))
return 0;
/*
* if it doesn't have slice left, forget it
*/
if (new_cfqq->slice_left < cfqd->cfq_slice_idle)
return 0;
- if (crq->is_sync && !cfq_cfqq_sync(cfqq))
+ if (cfq_crq_is_sync(crq) && !cfq_cfqq_sync(cfqq))
return 1;
return 0;
@@ -1614,7 +1732,7 @@
cfqq->slice_left = cfq_prio_to_slice(cfqd, cfqq) / 2;
cfqq->slice_end = cfqq->slice_left + jiffies;
- cfq_slice_expired(cfqd, 1);
+ __cfq_slice_expired(cfqd, cfqq, 1);
__cfq_set_active_queue(cfqd, cfqq);
}
@@ -1639,7 +1757,7 @@
cfq_crq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq,
struct cfq_rq *crq)
{
- const int sync = crq->is_sync;
+ const int sync = cfq_crq_is_sync(crq);
cfqq->next_crq = cfq_choose_req(cfqd, cfqq->next_crq, crq);
@@ -1658,8 +1776,8 @@
* immediately and flag that we must not expire this queue
* just now
*/
- if (cfqq->wait_request) {
- cfqq->must_dispatch = 1;
+ if (cfq_cfqq_wait_request(cfqq)) {
+ cfq_mark_cfqq_must_dispatch(cfqq);
del_timer(&cfqd->idle_slice_timer);
cfq_start_queueing(cfqd, cfqq);
}
@@ -1670,7 +1788,7 @@
* has some old slice time left and is of higher priority
*/
cfq_preempt_queue(cfqd, cfqq);
- cfqq->must_dispatch = 1;
+ cfq_mark_cfqq_must_dispatch(cfqq);
cfq_start_queueing(cfqd, cfqq);
}
}
@@ -1713,7 +1831,7 @@
* be kicked by __make_request() afterward.
* Kick it here.
*/
- kblockd_schedule_work(&cfqd->unplug_work);
+ cfq_schedule_dispatch(cfqd);
break;
case ELEVATOR_INSERT_FRONT:
list_add(&rq->queuelist, &q->queue_head);
@@ -1750,9 +1868,11 @@
cfqq = crq->cfq_queue;
- if (crq->in_flight) {
- WARN_ON(!cfqq->in_flight);
- cfqq->in_flight--;
+ if (cfq_crq_in_flight(crq)) {
+ const int sync = cfq_crq_is_sync(crq);
+
+ WARN_ON(!cfqq->on_dispatch[sync]);
+ cfqq->on_dispatch[sync]--;
}
cfq_account_completion(cfqq, crq);
@@ -1814,7 +1934,7 @@
* refile between round-robin lists if we moved the priority class
*/
if ((ioprio_class != cfqq->ioprio_class || ioprio != cfqq->ioprio) &&
- cfqq->on_rr)
+ cfq_cfqq_on_rr(cfqq))
cfq_resort_rr_list(cfqq, 0);
}
@@ -1830,23 +1950,27 @@
__cfq_may_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq,
struct task_struct *task, int rw)
{
- if (cfqq->wait_request && cfqq->must_alloc)
+#if 1
+ if ((cfq_cfqq_wait_request(cfqq) || cfq_cfqq_must_alloc(cfqq)) &&
+ !cfq_cfqq_must_alloc_slice) {
+ cfq_mark_cfqq_must_alloc_slice(cfqq);
return ELV_MQUEUE_MUST;
+ }
return ELV_MQUEUE_MAY;
-#if 0
+#else
if (!cfqq || task->flags & PF_MEMALLOC)
return ELV_MQUEUE_MAY;
- if (!cfqq->allocated[rw] || cfqq->must_alloc) {
- if (cfqq->wait_request)
+ if (!cfqq->allocated[rw] || cfq_cfqq_must_alloc(cfqq)) {
+ if (cfq_cfqq_wait_request(cfqq))
return ELV_MQUEUE_MUST;
/*
* only allow 1 ELV_MQUEUE_MUST per slice, otherwise we
* can quickly flood the queue with writes from a single task
*/
- if (rw == READ || !cfqq->must_alloc_slice) {
- cfqq->must_alloc_slice = 1;
+ if (rw == READ || !cfq_cfqq_must_alloc_slice) {
+ cfq_mark_cfqq_must_alloc_slice(cfqq);
return ELV_MQUEUE_MUST;
}
@@ -1881,7 +2005,7 @@
* so just lookup a possibly existing queue, or return 'may queue'
* if that fails
*/
- cfqq = cfq_find_cfq_hash(cfqd, cfq_queue_pid(tsk, rw));
+ cfqq = cfq_find_cfq_hash(cfqd, cfq_queue_pid(tsk, rw), tsk->ioprio);
if (cfqq) {
cfq_init_prio_data(cfqq);
cfq_prio_boost(cfqq);
@@ -1943,15 +2067,17 @@
int gfp_mask)
{
struct cfq_data *cfqd = q->elevator->elevator_data;
+ struct task_struct *tsk = current;
struct cfq_io_context *cic;
const int rw = rq_data_dir(rq);
+ pid_t key = cfq_queue_pid(tsk, rw);
struct cfq_queue *cfqq;
struct cfq_rq *crq;
unsigned long flags;
might_sleep_if(gfp_mask & __GFP_WAIT);
- cic = cfq_get_io_context(cfqd, cfq_queue_pid(current, rw), gfp_mask);
+ cic = cfq_get_io_context(cfqd, key, gfp_mask);
spin_lock_irqsave(q->queue_lock, flags);
@@ -1959,7 +2085,7 @@
goto queue_fail;
if (!cic->cfqq) {
- cfqq = cfq_get_queue(cfqd, current->pid, gfp_mask);
+ cfqq = cfq_get_queue(cfqd, key, tsk->ioprio, gfp_mask);
if (!cfqq)
goto queue_fail;
@@ -1968,7 +2094,7 @@
cfqq = cic->cfqq;
cfqq->allocated[rw]++;
- cfqq->must_alloc = 0;
+ cfq_clear_cfqq_must_alloc(cfqq);
cfqd->rq_starved = 0;
atomic_inc(&cfqq->ref);
spin_unlock_irqrestore(q->queue_lock, flags);
@@ -1981,9 +2107,15 @@
INIT_HLIST_NODE(&crq->hash);
crq->cfq_queue = cfqq;
crq->io_context = cic;
- crq->in_flight = crq->accounted = 0;
- crq->is_sync = (rw == READ || process_sync(current));
- crq->requeued = 0;
+ cfq_clear_crq_in_flight(crq);
+ cfq_clear_crq_in_driver(crq);
+ cfq_clear_crq_requeued(crq);
+
+ if (rw == READ || process_sync(tsk))
+ cfq_mark_crq_is_sync(crq);
+ else
+ cfq_clear_crq_is_sync(crq);
+
rq->elevator_private = crq;
return 0;
}
@@ -1991,7 +2123,7 @@
spin_lock_irqsave(q->queue_lock, flags);
cfqq->allocated[rw]--;
if (!(cfqq->allocated[0] + cfqq->allocated[1]))
- cfqq->must_alloc = 1;
+ cfq_mark_cfqq_must_alloc(cfqq);
cfq_put_queue(cfqq);
queue_fail:
if (cic)
@@ -2002,7 +2134,7 @@
* that would be an extremely rare OOM situation
*/
cfqd->rq_starved = 1;
- kblockd_schedule_work(&cfqd->unplug_work);
+ cfq_schedule_dispatch(cfqd);
spin_unlock_irqrestore(q->queue_lock, flags);
return 1;
}
@@ -2068,15 +2200,14 @@
* not expired and it has a request pending, let it dispatch
*/
if (!RB_EMPTY(&cfqq->sort_list)) {
- cfqq->must_dispatch = 1;
+ cfq_mark_cfqq_must_dispatch(cfqq);
goto out_kick;
}
}
expire:
cfq_slice_expired(cfqd, 0);
out_kick:
- if (cfq_pending_requests(cfqd))
- kblockd_schedule_work(&cfqd->unplug_work);
+ cfq_schedule_dispatch(cfqd);
out_cont:
spin_unlock_irqrestore(cfqd->queue->queue_lock, flags);
}
@@ -2099,11 +2230,17 @@
cfqd->idle_class_timer.expires = end;
add_timer(&cfqd->idle_class_timer);
} else
- kblockd_schedule_work(&cfqd->unplug_work);
+ cfq_schedule_dispatch(cfqd);
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);
+ del_timer_sync(&cfqd->idle_class_timer);
+ blk_sync_queue(cfqd->queue);
+}
static void cfq_put_cfqd(struct cfq_data *cfqd)
{
@@ -2112,7 +2249,7 @@
if (!atomic_dec_and_test(&cfqd->ref))
return;
- blk_sync_queue(q);
+ cfq_shutdown_timer_wq(cfqd);
blk_put_queue(q);
@@ -2126,8 +2263,7 @@
{
struct cfq_data *cfqd = e->elevator_data;
- del_timer_sync(&cfqd->idle_slice_timer);
- del_timer_sync(&cfqd->idle_class_timer);
+ cfq_shutdown_timer_wq(cfqd);
cfq_put_cfqd(cfqd);
}
@@ -2198,6 +2334,7 @@
cfqd->cfq_slice_async_rq = cfq_slice_async_rq;
cfqd->cfq_slice_idle = cfq_slice_idle;
cfqd->cfq_max_depth = cfq_max_depth;
+
return 0;
out_crqpool:
kfree(cfqd->cfq_hash);
@@ -2369,6 +2506,7 @@
.show = cfq_max_depth_show,
.store = cfq_max_depth_store,
};
+
static struct attribute *default_attrs[] = {
&cfq_quantum_entry.attr,
&cfq_queued_entry.attr,