#include "blk.h"
#include "cfq.h"
+static struct blkio_policy_type blkio_policy_cfq;
+
/*
* tunables
*/
unsigned long saved_workload_slice;
enum wl_type_t saved_workload;
enum wl_prio_t saved_serving_prio;
- struct blkio_group blkg;
-#ifdef CONFIG_CFQ_GROUP_IOSCHED
- struct hlist_node cfqd_node;
- int ref;
-#endif
+
/* number of requests that are on the dispatch list or inside driver */
int dispatched;
struct cfq_ttime ttime;
struct request_queue *queue;
/* Root service tree for cfq_groups */
struct cfq_rb_root grp_service_tree;
- struct cfq_group root_group;
+ struct cfq_group *root_group;
/*
* The priority currently being served
struct cfq_queue oom_cfqq;
unsigned long last_delayed_sync;
+};
- /* List of cfq groups being managed on this device*/
- struct hlist_head cfqg_list;
+static inline struct cfq_group *blkg_to_cfqg(struct blkio_group *blkg)
+{
+ return blkg_to_pdata(blkg, &blkio_policy_cfq);
+}
- /* Number of groups which are on blkcg->blkg_list */
- unsigned int nr_blkcg_linked_grps;
-};
+static inline struct blkio_group *cfqg_to_blkg(struct cfq_group *cfqg)
+{
+ return pdata_to_blkg(cfqg, &blkio_policy_cfq);
+}
static struct cfq_group *cfq_get_next_cfqg(struct cfq_data *cfqd);
#define cfq_log_cfqq(cfqd, cfqq, fmt, args...) \
blk_add_trace_msg((cfqd)->queue, "cfq%d%c %s " fmt, (cfqq)->pid, \
cfq_cfqq_sync((cfqq)) ? 'S' : 'A', \
- blkg_path(&(cfqq)->cfqg->blkg), ##args)
+ blkg_path(cfqg_to_blkg((cfqq)->cfqg)), ##args)
#define cfq_log_cfqg(cfqd, cfqg, fmt, args...) \
blk_add_trace_msg((cfqd)->queue, "%s " fmt, \
- blkg_path(&(cfqg)->blkg), ##args) \
+ blkg_path(cfqg_to_blkg((cfqg))), ##args) \
#else
#define cfq_log_cfqq(cfqd, cfqq, fmt, args...) \
cfq_log_cfqg(cfqd, cfqg, "del_from_rr group");
cfq_group_service_tree_del(st, cfqg);
cfqg->saved_workload_slice = 0;
- cfq_blkiocg_update_dequeue_stats(&cfqg->blkg, 1);
+ cfq_blkiocg_update_dequeue_stats(cfqg_to_blkg(cfqg),
+ &blkio_policy_cfq, 1);
}
static inline unsigned int cfq_cfqq_slice_usage(struct cfq_queue *cfqq,
"sl_used=%u disp=%u charge=%u iops=%u sect=%lu",
used_sl, cfqq->slice_dispatch, charge,
iops_mode(cfqd), cfqq->nr_sectors);
- cfq_blkiocg_update_timeslice_used(&cfqg->blkg, used_sl,
- unaccounted_sl);
- cfq_blkiocg_set_start_empty_time(&cfqg->blkg);
+ cfq_blkiocg_update_timeslice_used(cfqg_to_blkg(cfqg), &blkio_policy_cfq,
+ used_sl, unaccounted_sl);
+ cfq_blkiocg_set_start_empty_time(cfqg_to_blkg(cfqg), &blkio_policy_cfq);
}
-#ifdef CONFIG_CFQ_GROUP_IOSCHED
-static inline struct cfq_group *cfqg_of_blkg(struct blkio_group *blkg)
-{
- if (blkg)
- return container_of(blkg, struct cfq_group, blkg);
- return NULL;
-}
-
-static void cfq_update_blkio_group_weight(void *key, struct blkio_group *blkg,
- unsigned int weight)
-{
- struct cfq_group *cfqg = cfqg_of_blkg(blkg);
- cfqg->new_weight = weight;
- cfqg->needs_update = true;
-}
-
-static void cfq_init_add_cfqg_lists(struct cfq_data *cfqd,
- struct cfq_group *cfqg, struct blkio_cgroup *blkcg)
-{
- struct backing_dev_info *bdi = &cfqd->queue->backing_dev_info;
- unsigned int major, minor;
-
- /*
- * Add group onto cgroup list. It might happen that bdi->dev is
- * not initialized yet. Initialize this new group without major
- * and minor info and this info will be filled in once a new thread
- * comes for IO.
- */
- if (bdi->dev) {
- sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor);
- cfq_blkiocg_add_blkio_group(blkcg, &cfqg->blkg,
- (void *)cfqd, MKDEV(major, minor));
- } else
- cfq_blkiocg_add_blkio_group(blkcg, &cfqg->blkg,
- (void *)cfqd, 0);
-
- cfqd->nr_blkcg_linked_grps++;
- cfqg->weight = blkcg_get_weight(blkcg, cfqg->blkg.dev);
-
- /* Add group on cfqd list */
- hlist_add_head(&cfqg->cfqd_node, &cfqd->cfqg_list);
-}
-
-/*
- * Should be called from sleepable context. No request queue lock as per
- * cpu stats are allocated dynamically and alloc_percpu needs to be called
- * from sleepable context.
+/**
+ * cfq_init_cfqg_base - initialize base part of a cfq_group
+ * @cfqg: cfq_group to initialize
+ *
+ * Initialize the base part which is used whether %CONFIG_CFQ_GROUP_IOSCHED
+ * is enabled or not.
*/
-static struct cfq_group * cfq_alloc_cfqg(struct cfq_data *cfqd)
+static void cfq_init_cfqg_base(struct cfq_group *cfqg)
{
- struct cfq_group *cfqg = NULL;
- int i, j, ret;
struct cfq_rb_root *st;
-
- cfqg = kzalloc_node(sizeof(*cfqg), GFP_ATOMIC, cfqd->queue->node);
- if (!cfqg)
- return NULL;
+ int i, j;
for_each_cfqg_st(cfqg, i, j, st)
*st = CFQ_RB_ROOT;
RB_CLEAR_NODE(&cfqg->rb_node);
cfqg->ttime.last_end_request = jiffies;
-
- /*
- * Take the initial reference that will be released on destroy
- * This can be thought of a joint reference by cgroup and
- * elevator which will be dropped by either elevator exit
- * or cgroup deletion path depending on who is exiting first.
- */
- cfqg->ref = 1;
-
- ret = blkio_alloc_blkg_stats(&cfqg->blkg);
- if (ret) {
- kfree(cfqg);
- return NULL;
- }
-
- return cfqg;
}
-static struct cfq_group *
-cfq_find_cfqg(struct cfq_data *cfqd, struct blkio_cgroup *blkcg)
+#ifdef CONFIG_CFQ_GROUP_IOSCHED
+static void cfq_update_blkio_group_weight(struct request_queue *q,
+ struct blkio_group *blkg,
+ unsigned int weight)
{
- struct cfq_group *cfqg = NULL;
- void *key = cfqd;
- struct backing_dev_info *bdi = &cfqd->queue->backing_dev_info;
- unsigned int major, minor;
+ struct cfq_group *cfqg = blkg_to_cfqg(blkg);
- /*
- * This is the common case when there are no blkio cgroups.
- * Avoid lookup in this case
- */
- if (blkcg == &blkio_root_cgroup)
- cfqg = &cfqd->root_group;
- else
- cfqg = cfqg_of_blkg(blkiocg_lookup_group(blkcg, key));
+ cfqg->new_weight = weight;
+ cfqg->needs_update = true;
+}
- if (cfqg && !cfqg->blkg.dev && bdi->dev && dev_name(bdi->dev)) {
- sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor);
- cfqg->blkg.dev = MKDEV(major, minor);
- }
+static void cfq_init_blkio_group(struct blkio_group *blkg)
+{
+ struct cfq_group *cfqg = blkg_to_cfqg(blkg);
- return cfqg;
+ cfq_init_cfqg_base(cfqg);
+ cfqg->weight = blkg->blkcg->weight;
}
/*
* Search for the cfq group current task belongs to. request_queue lock must
* be held.
*/
-static struct cfq_group *cfq_get_cfqg(struct cfq_data *cfqd)
+static struct cfq_group *cfq_lookup_create_cfqg(struct cfq_data *cfqd,
+ struct blkio_cgroup *blkcg)
{
- struct blkio_cgroup *blkcg;
- struct cfq_group *cfqg = NULL, *__cfqg = NULL;
struct request_queue *q = cfqd->queue;
+ struct cfq_group *cfqg = NULL;
- rcu_read_lock();
- blkcg = task_blkio_cgroup(current);
- cfqg = cfq_find_cfqg(cfqd, blkcg);
- if (cfqg) {
- rcu_read_unlock();
- return cfqg;
- }
-
- /*
- * Need to allocate a group. Allocation of group also needs allocation
- * of per cpu stats which in-turn takes a mutex() and can block. Hence
- * we need to drop rcu lock and queue_lock before we call alloc.
- *
- * Not taking any queue reference here and assuming that queue is
- * around by the time we return. CFQ queue allocation code does
- * the same. It might be racy though.
- */
-
- rcu_read_unlock();
- spin_unlock_irq(q->queue_lock);
-
- cfqg = cfq_alloc_cfqg(cfqd);
-
- spin_lock_irq(q->queue_lock);
-
- rcu_read_lock();
- blkcg = task_blkio_cgroup(current);
-
- /*
- * If some other thread already allocated the group while we were
- * not holding queue lock, free up the group
- */
- __cfqg = cfq_find_cfqg(cfqd, blkcg);
+ /* avoid lookup for the common case where there's no blkio cgroup */
+ if (blkcg == &blkio_root_cgroup) {
+ cfqg = cfqd->root_group;
+ } else {
+ struct blkio_group *blkg;
- if (__cfqg) {
- kfree(cfqg);
- rcu_read_unlock();
- return __cfqg;
+ blkg = blkg_lookup_create(blkcg, q, BLKIO_POLICY_PROP, false);
+ if (!IS_ERR(blkg))
+ cfqg = blkg_to_cfqg(blkg);
}
- if (!cfqg)
- cfqg = &cfqd->root_group;
-
- cfq_init_add_cfqg_lists(cfqd, cfqg, blkcg);
- rcu_read_unlock();
- return cfqg;
-}
-
-static inline struct cfq_group *cfq_ref_get_cfqg(struct cfq_group *cfqg)
-{
- cfqg->ref++;
return cfqg;
}
{
/* Currently, all async queues are mapped to root group */
if (!cfq_cfqq_sync(cfqq))
- cfqg = &cfqq->cfqd->root_group;
+ cfqg = cfqq->cfqd->root_group;
cfqq->cfqg = cfqg;
/* cfqq reference on cfqg */
- cfqq->cfqg->ref++;
-}
-
-static void cfq_put_cfqg(struct cfq_group *cfqg)
-{
- struct cfq_rb_root *st;
- int i, j;
-
- BUG_ON(cfqg->ref <= 0);
- cfqg->ref--;
- if (cfqg->ref)
- return;
- for_each_cfqg_st(cfqg, i, j, st)
- BUG_ON(!RB_EMPTY_ROOT(&st->rb));
- free_percpu(cfqg->blkg.stats_cpu);
- kfree(cfqg);
-}
-
-static void cfq_destroy_cfqg(struct cfq_data *cfqd, struct cfq_group *cfqg)
-{
- /* Something wrong if we are trying to remove same group twice */
- BUG_ON(hlist_unhashed(&cfqg->cfqd_node));
-
- hlist_del_init(&cfqg->cfqd_node);
-
- BUG_ON(cfqd->nr_blkcg_linked_grps <= 0);
- cfqd->nr_blkcg_linked_grps--;
-
- /*
- * Put the reference taken at the time of creation so that when all
- * queues are gone, group can be destroyed.
- */
- cfq_put_cfqg(cfqg);
-}
-
-static void cfq_release_cfq_groups(struct cfq_data *cfqd)
-{
- struct hlist_node *pos, *n;
- struct cfq_group *cfqg;
-
- hlist_for_each_entry_safe(cfqg, pos, n, &cfqd->cfqg_list, cfqd_node) {
- /*
- * If cgroup removal path got to blk_group first and removed
- * it from cgroup list, then it will take care of destroying
- * cfqg also.
- */
- if (!cfq_blkiocg_del_blkio_group(&cfqg->blkg))
- cfq_destroy_cfqg(cfqd, cfqg);
- }
-}
-
-/*
- * Blk cgroup controller notification saying that blkio_group object is being
- * delinked as associated cgroup object is going away. That also means that
- * no new IO will come in this group. So get rid of this group as soon as
- * any pending IO in the group is finished.
- *
- * This function is called under rcu_read_lock(). key is the rcu protected
- * pointer. That means "key" is a valid cfq_data pointer as long as we are rcu
- * read lock.
- *
- * "key" was fetched from blkio_group under blkio_cgroup->lock. That means
- * it should not be NULL as even if elevator was exiting, cgroup deltion
- * path got to it first.
- */
-static void cfq_unlink_blkio_group(void *key, struct blkio_group *blkg)
-{
- unsigned long flags;
- struct cfq_data *cfqd = key;
-
- spin_lock_irqsave(cfqd->queue->queue_lock, flags);
- cfq_destroy_cfqg(cfqd, cfqg_of_blkg(blkg));
- spin_unlock_irqrestore(cfqd->queue->queue_lock, flags);
+ blkg_get(cfqg_to_blkg(cfqg));
}
#else /* GROUP_IOSCHED */
-static struct cfq_group *cfq_get_cfqg(struct cfq_data *cfqd)
+static struct cfq_group *cfq_lookup_create_cfqg(struct cfq_data *cfqd,
+ struct blkio_cgroup *blkcg)
{
- return &cfqd->root_group;
-}
-
-static inline struct cfq_group *cfq_ref_get_cfqg(struct cfq_group *cfqg)
-{
- return cfqg;
+ return cfqd->root_group;
}
static inline void
cfqq->cfqg = cfqg;
}
-static void cfq_release_cfq_groups(struct cfq_data *cfqd) {}
-static inline void cfq_put_cfqg(struct cfq_group *cfqg) {}
-
#endif /* GROUP_IOSCHED */
/*
{
elv_rb_del(&cfqq->sort_list, rq);
cfqq->queued[rq_is_sync(rq)]--;
- cfq_blkiocg_update_io_remove_stats(&(RQ_CFQG(rq))->blkg,
- rq_data_dir(rq), rq_is_sync(rq));
+ cfq_blkiocg_update_io_remove_stats(cfqg_to_blkg(RQ_CFQG(rq)),
+ &blkio_policy_cfq, rq_data_dir(rq),
+ rq_is_sync(rq));
cfq_add_rq_rb(rq);
- cfq_blkiocg_update_io_add_stats(&(RQ_CFQG(rq))->blkg,
- &cfqq->cfqd->serving_group->blkg, rq_data_dir(rq),
- rq_is_sync(rq));
+ cfq_blkiocg_update_io_add_stats(cfqg_to_blkg(RQ_CFQG(rq)),
+ &blkio_policy_cfq,
+ cfqg_to_blkg(cfqq->cfqd->serving_group),
+ rq_data_dir(rq), rq_is_sync(rq));
}
static struct request *
cfq_del_rq_rb(rq);
cfqq->cfqd->rq_queued--;
- cfq_blkiocg_update_io_remove_stats(&(RQ_CFQG(rq))->blkg,
- rq_data_dir(rq), rq_is_sync(rq));
+ cfq_blkiocg_update_io_remove_stats(cfqg_to_blkg(RQ_CFQG(rq)),
+ &blkio_policy_cfq, rq_data_dir(rq),
+ rq_is_sync(rq));
if (rq->cmd_flags & REQ_PRIO) {
WARN_ON(!cfqq->prio_pending);
cfqq->prio_pending--;
static void cfq_bio_merged(struct request_queue *q, struct request *req,
struct bio *bio)
{
- cfq_blkiocg_update_io_merged_stats(&(RQ_CFQG(req))->blkg,
- bio_data_dir(bio), cfq_bio_sync(bio));
+ cfq_blkiocg_update_io_merged_stats(cfqg_to_blkg(RQ_CFQG(req)),
+ &blkio_policy_cfq, bio_data_dir(bio),
+ cfq_bio_sync(bio));
}
static void
if (cfqq->next_rq == next)
cfqq->next_rq = rq;
cfq_remove_request(next);
- cfq_blkiocg_update_io_merged_stats(&(RQ_CFQG(rq))->blkg,
- rq_data_dir(next), rq_is_sync(next));
+ cfq_blkiocg_update_io_merged_stats(cfqg_to_blkg(RQ_CFQG(rq)),
+ &blkio_policy_cfq, rq_data_dir(next),
+ rq_is_sync(next));
cfqq = RQ_CFQQ(next);
/*
/*
* Lookup the cfqq that this bio will be queued with and allow
- * merge only if rq is queued there. This function can be called
- * from plug merge without queue_lock. In such cases, ioc of @rq
- * and %current are guaranteed to be equal. Avoid lookup which
- * requires queue_lock by using @rq's cic.
+ * merge only if rq is queued there.
*/
- if (current->io_context == RQ_CIC(rq)->icq.ioc) {
- cic = RQ_CIC(rq);
- } else {
- cic = cfq_cic_lookup(cfqd, current->io_context);
- if (!cic)
- return false;
- }
+ cic = cfq_cic_lookup(cfqd, current->io_context);
+ if (!cic)
+ return false;
cfqq = cic_to_cfqq(cic, cfq_bio_sync(bio));
return cfqq == RQ_CFQQ(rq);
static inline void cfq_del_timer(struct cfq_data *cfqd, struct cfq_queue *cfqq)
{
del_timer(&cfqd->idle_slice_timer);
- cfq_blkiocg_update_idle_time_stats(&cfqq->cfqg->blkg);
+ cfq_blkiocg_update_idle_time_stats(cfqg_to_blkg(cfqq->cfqg),
+ &blkio_policy_cfq);
}
static void __cfq_set_active_queue(struct cfq_data *cfqd,
if (cfqq) {
cfq_log_cfqq(cfqd, cfqq, "set_active wl_prio:%d wl_type:%d",
cfqd->serving_prio, cfqd->serving_type);
- cfq_blkiocg_update_avg_queue_size_stats(&cfqq->cfqg->blkg);
+ cfq_blkiocg_update_avg_queue_size_stats(cfqg_to_blkg(cfqq->cfqg),
+ &blkio_policy_cfq);
cfqq->slice_start = 0;
cfqq->dispatch_start = jiffies;
cfqq->allocated_slice = 0;
cfqd->active_queue = NULL;
if (cfqd->active_cic) {
- put_io_context(cfqd->active_cic->icq.ioc, cfqd->queue);
+ put_io_context(cfqd->active_cic->icq.ioc);
cfqd->active_cic = NULL;
}
}
sl = cfqd->cfq_slice_idle;
mod_timer(&cfqd->idle_slice_timer, jiffies + sl);
- cfq_blkiocg_update_set_idle_time_stats(&cfqq->cfqg->blkg);
+ cfq_blkiocg_update_set_idle_time_stats(cfqg_to_blkg(cfqq->cfqg),
+ &blkio_policy_cfq);
cfq_log_cfqq(cfqd, cfqq, "arm_idle: %lu group_idle: %d", sl,
group_idle ? 1 : 0);
}
cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]++;
cfqq->nr_sectors += blk_rq_sectors(rq);
- cfq_blkiocg_update_dispatch_stats(&cfqq->cfqg->blkg, blk_rq_bytes(rq),
- rq_data_dir(rq), rq_is_sync(rq));
+ cfq_blkiocg_update_dispatch_stats(cfqg_to_blkg(cfqq->cfqg),
+ &blkio_policy_cfq, blk_rq_bytes(rq),
+ rq_data_dir(rq), rq_is_sync(rq));
}
/*
BUG_ON(cfq_cfqq_on_rr(cfqq));
kmem_cache_free(cfq_pool, cfqq);
- cfq_put_cfqg(cfqg);
+ blkg_put(cfqg_to_blkg(cfqg));
}
static void cfq_put_cooperator(struct cfq_queue *cfqq)
cfq_find_alloc_queue(struct cfq_data *cfqd, bool is_sync,
struct io_context *ioc, gfp_t gfp_mask)
{
+ struct blkio_cgroup *blkcg;
struct cfq_queue *cfqq, *new_cfqq = NULL;
struct cfq_io_cq *cic;
struct cfq_group *cfqg;
retry:
- cfqg = cfq_get_cfqg(cfqd);
+ rcu_read_lock();
+
+ blkcg = task_blkio_cgroup(current);
+
+ cfqg = cfq_lookup_create_cfqg(cfqd, blkcg);
+
cic = cfq_cic_lookup(cfqd, ioc);
/* cic always exists here */
cfqq = cic_to_cfqq(cic, is_sync);
cfqq = new_cfqq;
new_cfqq = NULL;
} else if (gfp_mask & __GFP_WAIT) {
+ rcu_read_unlock();
spin_unlock_irq(cfqd->queue->queue_lock);
new_cfqq = kmem_cache_alloc_node(cfq_pool,
gfp_mask | __GFP_ZERO,
if (new_cfqq)
kmem_cache_free(cfq_pool, new_cfqq);
+ rcu_read_unlock();
return cfqq;
}
*/
static void cfq_preempt_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq)
{
- struct cfq_queue *old_cfqq = cfqd->active_queue;
+ enum wl_type_t old_type = cfqq_type(cfqd->active_queue);
cfq_log_cfqq(cfqd, cfqq, "preempt");
cfq_slice_expired(cfqd, 1);
* workload type is changed, don't save slice, otherwise preempt
* doesn't happen
*/
- if (cfqq_type(old_cfqq) != cfqq_type(cfqq))
+ if (old_type != cfqq_type(cfqq))
cfqq->cfqg->saved_workload_slice = 0;
/*
__blk_run_queue(cfqd->queue);
} else {
cfq_blkiocg_update_idle_time_stats(
- &cfqq->cfqg->blkg);
+ cfqg_to_blkg(cfqq->cfqg),
+ &blkio_policy_cfq);
cfq_mark_cfqq_must_dispatch(cfqq);
}
}
rq_set_fifo_time(rq, jiffies + cfqd->cfq_fifo_expire[rq_is_sync(rq)]);
list_add_tail(&rq->queuelist, &cfqq->fifo);
cfq_add_rq_rb(rq);
- cfq_blkiocg_update_io_add_stats(&(RQ_CFQG(rq))->blkg,
- &cfqd->serving_group->blkg, rq_data_dir(rq),
- rq_is_sync(rq));
+ cfq_blkiocg_update_io_add_stats(cfqg_to_blkg(RQ_CFQG(rq)),
+ &blkio_policy_cfq,
+ cfqg_to_blkg(cfqd->serving_group),
+ rq_data_dir(rq), rq_is_sync(rq));
cfq_rq_enqueued(cfqd, cfqq, rq);
}
cfqd->rq_in_driver--;
cfqq->dispatched--;
(RQ_CFQG(rq))->dispatched--;
- cfq_blkiocg_update_completion_stats(&cfqq->cfqg->blkg,
- rq_start_time_ns(rq), rq_io_start_time_ns(rq),
- rq_data_dir(rq), rq_is_sync(rq));
+ cfq_blkiocg_update_completion_stats(cfqg_to_blkg(cfqq->cfqg),
+ &blkio_policy_cfq, rq_start_time_ns(rq),
+ rq_io_start_time_ns(rq), rq_data_dir(rq),
+ rq_is_sync(rq));
cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]--;
cfqq->allocated[rw]--;
/* Put down rq reference on cfqg */
- cfq_put_cfqg(RQ_CFQG(rq));
+ blkg_put(cfqg_to_blkg(RQ_CFQG(rq)));
rq->elv.priv[0] = NULL;
rq->elv.priv[1] = NULL;
const int rw = rq_data_dir(rq);
const bool is_sync = rq_is_sync(rq);
struct cfq_queue *cfqq;
+ unsigned int changed;
might_sleep_if(gfp_mask & __GFP_WAIT);
spin_lock_irq(q->queue_lock);
/* handle changed notifications */
- if (unlikely(cic->icq.changed)) {
- if (test_and_clear_bit(ICQ_IOPRIO_CHANGED, &cic->icq.changed))
- changed_ioprio(cic);
+ changed = icq_get_changed(&cic->icq);
+ if (unlikely(changed & ICQ_IOPRIO_CHANGED))
+ changed_ioprio(cic);
#ifdef CONFIG_CFQ_GROUP_IOSCHED
- if (test_and_clear_bit(ICQ_CGROUP_CHANGED, &cic->icq.changed))
- changed_cgroup(cic);
+ if (unlikely(changed & ICQ_CGROUP_CHANGED))
+ changed_cgroup(cic);
#endif
- }
new_queue:
cfqq = cic_to_cfqq(cic, is_sync);
cfqq->allocated[rw]++;
cfqq->ref++;
+ blkg_get(cfqg_to_blkg(cfqq->cfqg));
rq->elv.priv[0] = cfqq;
- rq->elv.priv[1] = cfq_ref_get_cfqg(cfqq->cfqg);
+ rq->elv.priv[1] = cfqq->cfqg;
spin_unlock_irq(q->queue_lock);
return 0;
}
__cfq_slice_expired(cfqd, cfqd->active_queue, 0);
cfq_put_async_queues(cfqd);
- cfq_release_cfq_groups(cfqd);
+ spin_unlock_irq(q->queue_lock);
+
+#ifdef CONFIG_BLK_CGROUP
/*
* If there are groups which we could not unlink from blkcg list,
* wait for a rcu period for them to be freed.
*/
- if (cfqd->nr_blkcg_linked_grps)
- wait = true;
-
+ spin_lock_irq(q->queue_lock);
+ wait = q->nr_blkgs;
spin_unlock_irq(q->queue_lock);
-
+#endif
cfq_shutdown_timer_wq(cfqd);
/*
if (wait)
synchronize_rcu();
-#ifdef CONFIG_CFQ_GROUP_IOSCHED
- /* Free up per cpu stats for root group */
- free_percpu(cfqd->root_group.blkg.stats_cpu);
+#ifndef CONFIG_CFQ_GROUP_IOSCHED
+ kfree(cfqd->root_group);
#endif
+ update_root_blkg_pd(q, BLKIO_POLICY_PROP);
kfree(cfqd);
}
-static void *cfq_init_queue(struct request_queue *q)
+static int cfq_init_queue(struct request_queue *q)
{
struct cfq_data *cfqd;
- int i, j;
- struct cfq_group *cfqg;
- struct cfq_rb_root *st;
+ struct blkio_group *blkg __maybe_unused;
+ int i;
cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL | __GFP_ZERO, q->node);
if (!cfqd)
- return NULL;
+ return -ENOMEM;
+
+ cfqd->queue = q;
+ q->elevator->elevator_data = cfqd;
/* Init root service tree */
cfqd->grp_service_tree = CFQ_RB_ROOT;
- /* Init root group */
- cfqg = &cfqd->root_group;
- for_each_cfqg_st(cfqg, i, j, st)
- *st = CFQ_RB_ROOT;
- RB_CLEAR_NODE(&cfqg->rb_node);
-
- /* Give preference to root group over other groups */
- cfqg->weight = 2*BLKIO_WEIGHT_DEFAULT;
-
+ /* Init root group and prefer root group over other groups by default */
#ifdef CONFIG_CFQ_GROUP_IOSCHED
- /*
- * Set root group reference to 2. One reference will be dropped when
- * all groups on cfqd->cfqg_list are being deleted during queue exit.
- * Other reference will remain there as we don't want to delete this
- * group as it is statically allocated and gets destroyed when
- * throtl_data goes away.
- */
- cfqg->ref = 2;
+ rcu_read_lock();
+ spin_lock_irq(q->queue_lock);
+
+ blkg = blkg_lookup_create(&blkio_root_cgroup, q, BLKIO_POLICY_PROP,
+ true);
+ if (!IS_ERR(blkg))
+ cfqd->root_group = blkg_to_cfqg(blkg);
- if (blkio_alloc_blkg_stats(&cfqg->blkg)) {
- kfree(cfqg);
+ spin_unlock_irq(q->queue_lock);
+ rcu_read_unlock();
+#else
+ cfqd->root_group = kzalloc_node(sizeof(*cfqd->root_group),
+ GFP_KERNEL, cfqd->queue->node);
+ if (cfqd->root_group)
+ cfq_init_cfqg_base(cfqd->root_group);
+#endif
+ if (!cfqd->root_group) {
kfree(cfqd);
- return NULL;
+ return -ENOMEM;
}
- rcu_read_lock();
-
- cfq_blkiocg_add_blkio_group(&blkio_root_cgroup, &cfqg->blkg,
- (void *)cfqd, 0);
- rcu_read_unlock();
- cfqd->nr_blkcg_linked_grps++;
+ cfqd->root_group->weight = 2*BLKIO_WEIGHT_DEFAULT;
- /* Add group on cfqd->cfqg_list */
- hlist_add_head(&cfqg->cfqd_node, &cfqd->cfqg_list);
-#endif
/*
* Not strictly needed (since RB_ROOT just clears the node and we
* zeroed cfqd on alloc), but better be safe in case someone decides
/*
* Our fallback cfqq if cfq_find_alloc_queue() runs into OOM issues.
* Grab a permanent reference to it, so that the normal code flow
- * will not attempt to free it.
+ * will not attempt to free it. oom_cfqq is linked to root_group
+ * but shouldn't hold a reference as it'll never be unlinked. Lose
+ * the reference from linking right away.
*/
cfq_init_cfqq(cfqd, &cfqd->oom_cfqq, 1, 0);
cfqd->oom_cfqq.ref++;
- cfq_link_cfqq_cfqg(&cfqd->oom_cfqq, &cfqd->root_group);
- cfqd->queue = q;
+ spin_lock_irq(q->queue_lock);
+ cfq_link_cfqq_cfqg(&cfqd->oom_cfqq, cfqd->root_group);
+ blkg_put(cfqg_to_blkg(cfqd->root_group));
+ spin_unlock_irq(q->queue_lock);
init_timer(&cfqd->idle_slice_timer);
cfqd->idle_slice_timer.function = cfq_idle_slice_timer;
* second, in order to have larger depth for async operations.
*/
cfqd->last_delayed_sync = jiffies - HZ;
- return cfqd;
+ return 0;
}
/*
#ifdef CONFIG_CFQ_GROUP_IOSCHED
static struct blkio_policy_type blkio_policy_cfq = {
.ops = {
- .blkio_unlink_group_fn = cfq_unlink_blkio_group,
+ .blkio_init_group_fn = cfq_init_blkio_group,
.blkio_update_group_weight_fn = cfq_update_blkio_group_weight,
},
.plid = BLKIO_POLICY_PROP,
+ .pdata_size = sizeof(struct cfq_group),
};
-#else
-static struct blkio_policy_type blkio_policy_cfq;
#endif
static int __init cfq_init(void)
return ret;
}
+#ifdef CONFIG_CFQ_GROUP_IOSCHED
blkio_policy_register(&blkio_policy_cfq);
-
+#endif
return 0;
}
static void __exit cfq_exit(void)
{
+#ifdef CONFIG_CFQ_GROUP_IOSCHED
blkio_policy_unregister(&blkio_policy_cfq);
+#endif
elv_unregister(&iosched_cfq);
kmem_cache_destroy(cfq_pool);
}