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-rw-r--r--block/bio.c50
-rw-r--r--block/blk-mq-sysfs.c9
-rw-r--r--block/blk-mq.c184
-rw-r--r--block/blk-mq.h1
-rw-r--r--block/cfq-iosched.c43
5 files changed, 178 insertions, 109 deletions
diff --git a/block/bio.c b/block/bio.c
index cf75915..f124a0a 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -296,13 +296,19 @@ void bio_reset(struct bio *bio)
}
EXPORT_SYMBOL(bio_reset);
-static void bio_chain_endio(struct bio *bio)
+static struct bio *__bio_chain_endio(struct bio *bio)
{
struct bio *parent = bio->bi_private;
- parent->bi_error = bio->bi_error;
- bio_endio(parent);
+ if (!parent->bi_error)
+ parent->bi_error = bio->bi_error;
bio_put(bio);
+ return parent;
+}
+
+static void bio_chain_endio(struct bio *bio)
+{
+ bio_endio(__bio_chain_endio(bio));
}
/*
@@ -1742,29 +1748,25 @@ static inline bool bio_remaining_done(struct bio *bio)
**/
void bio_endio(struct bio *bio)
{
- while (bio) {
- if (unlikely(!bio_remaining_done(bio)))
- break;
+again:
+ if (!bio_remaining_done(bio))
+ return;
- /*
- * Need to have a real endio function for chained bios,
- * otherwise various corner cases will break (like stacking
- * block devices that save/restore bi_end_io) - however, we want
- * to avoid unbounded recursion and blowing the stack. Tail call
- * optimization would handle this, but compiling with frame
- * pointers also disables gcc's sibling call optimization.
- */
- if (bio->bi_end_io == bio_chain_endio) {
- struct bio *parent = bio->bi_private;
- parent->bi_error = bio->bi_error;
- bio_put(bio);
- bio = parent;
- } else {
- if (bio->bi_end_io)
- bio->bi_end_io(bio);
- bio = NULL;
- }
+ /*
+ * Need to have a real endio function for chained bios, otherwise
+ * various corner cases will break (like stacking block devices that
+ * save/restore bi_end_io) - however, we want to avoid unbounded
+ * recursion and blowing the stack. Tail call optimization would
+ * handle this, but compiling with frame pointers also disables
+ * gcc's sibling call optimization.
+ */
+ if (bio->bi_end_io == bio_chain_endio) {
+ bio = __bio_chain_endio(bio);
+ goto again;
}
+
+ if (bio->bi_end_io)
+ bio->bi_end_io(bio);
}
EXPORT_SYMBOL(bio_endio);
diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c
index 1cf1878..431fdda 100644
--- a/block/blk-mq-sysfs.c
+++ b/block/blk-mq-sysfs.c
@@ -408,17 +408,18 @@ void blk_mq_unregister_disk(struct gendisk *disk)
blk_mq_enable_hotplug();
}
+void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx)
+{
+ kobject_init(&hctx->kobj, &blk_mq_hw_ktype);
+}
+
static void blk_mq_sysfs_init(struct request_queue *q)
{
- struct blk_mq_hw_ctx *hctx;
struct blk_mq_ctx *ctx;
int i;
kobject_init(&q->mq_kobj, &blk_mq_ktype);
- queue_for_each_hw_ctx(q, hctx, i)
- kobject_init(&hctx->kobj, &blk_mq_hw_ktype);
-
queue_for_each_ctx(q, ctx, i)
kobject_init(&ctx->kobj, &blk_mq_ctx_ktype);
}
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 56c0a72..050f7a1 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -544,7 +544,10 @@ EXPORT_SYMBOL(blk_mq_abort_requeue_list);
struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag)
{
- return tags->rqs[tag];
+ if (tag < tags->nr_tags)
+ return tags->rqs[tag];
+
+ return NULL;
}
EXPORT_SYMBOL(blk_mq_tag_to_rq);
@@ -1744,31 +1747,6 @@ static int blk_mq_init_hctx(struct request_queue *q,
return -1;
}
-static int blk_mq_init_hw_queues(struct request_queue *q,
- struct blk_mq_tag_set *set)
-{
- struct blk_mq_hw_ctx *hctx;
- unsigned int i;
-
- /*
- * Initialize hardware queues
- */
- queue_for_each_hw_ctx(q, hctx, i) {
- if (blk_mq_init_hctx(q, set, hctx, i))
- break;
- }
-
- if (i == q->nr_hw_queues)
- return 0;
-
- /*
- * Init failed
- */
- blk_mq_exit_hw_queues(q, set, i);
-
- return 1;
-}
-
static void blk_mq_init_cpu_queues(struct request_queue *q,
unsigned int nr_hw_queues)
{
@@ -1826,6 +1804,7 @@ static void blk_mq_map_swqueue(struct request_queue *q,
continue;
hctx = q->mq_ops->map_queue(q, i);
+
cpumask_set_cpu(i, hctx->cpumask);
ctx->index_hw = hctx->nr_ctx;
hctx->ctxs[hctx->nr_ctx++] = ctx;
@@ -1974,56 +1953,93 @@ struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set)
}
EXPORT_SYMBOL(blk_mq_init_queue);
-struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
- struct request_queue *q)
+static void blk_mq_realloc_hw_ctxs(struct blk_mq_tag_set *set,
+ struct request_queue *q)
{
- struct blk_mq_hw_ctx **hctxs;
- struct blk_mq_ctx __percpu *ctx;
- unsigned int *map;
- int i;
-
- ctx = alloc_percpu(struct blk_mq_ctx);
- if (!ctx)
- return ERR_PTR(-ENOMEM);
-
- hctxs = kmalloc_node(set->nr_hw_queues * sizeof(*hctxs), GFP_KERNEL,
- set->numa_node);
-
- if (!hctxs)
- goto err_percpu;
-
- map = blk_mq_make_queue_map(set);
- if (!map)
- goto err_map;
+ int i, j;
+ struct blk_mq_hw_ctx **hctxs = q->queue_hw_ctx;
+ blk_mq_sysfs_unregister(q);
for (i = 0; i < set->nr_hw_queues; i++) {
- int node = blk_mq_hw_queue_to_node(map, i);
+ int node;
+ if (hctxs[i])
+ continue;
+
+ node = blk_mq_hw_queue_to_node(q->mq_map, i);
hctxs[i] = kzalloc_node(sizeof(struct blk_mq_hw_ctx),
GFP_KERNEL, node);
if (!hctxs[i])
- goto err_hctxs;
+ break;
if (!zalloc_cpumask_var_node(&hctxs[i]->cpumask, GFP_KERNEL,
- node))
- goto err_hctxs;
+ node)) {
+ kfree(hctxs[i]);
+ hctxs[i] = NULL;
+ break;
+ }
atomic_set(&hctxs[i]->nr_active, 0);
hctxs[i]->numa_node = node;
hctxs[i]->queue_num = i;
+
+ if (blk_mq_init_hctx(q, set, hctxs[i], i)) {
+ free_cpumask_var(hctxs[i]->cpumask);
+ kfree(hctxs[i]);
+ hctxs[i] = NULL;
+ break;
+ }
+ blk_mq_hctx_kobj_init(hctxs[i]);
}
+ for (j = i; j < q->nr_hw_queues; j++) {
+ struct blk_mq_hw_ctx *hctx = hctxs[j];
+
+ if (hctx) {
+ if (hctx->tags) {
+ blk_mq_free_rq_map(set, hctx->tags, j);
+ set->tags[j] = NULL;
+ }
+ blk_mq_exit_hctx(q, set, hctx, j);
+ free_cpumask_var(hctx->cpumask);
+ kobject_put(&hctx->kobj);
+ kfree(hctx->ctxs);
+ kfree(hctx);
+ hctxs[j] = NULL;
+
+ }
+ }
+ q->nr_hw_queues = i;
+ blk_mq_sysfs_register(q);
+}
+
+struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
+ struct request_queue *q)
+{
+ /* mark the queue as mq asap */
+ q->mq_ops = set->ops;
+
+ q->queue_ctx = alloc_percpu(struct blk_mq_ctx);
+ if (!q->queue_ctx)
+ return ERR_PTR(-ENOMEM);
+
+ q->queue_hw_ctx = kzalloc_node(nr_cpu_ids * sizeof(*(q->queue_hw_ctx)),
+ GFP_KERNEL, set->numa_node);
+ if (!q->queue_hw_ctx)
+ goto err_percpu;
+
+ q->mq_map = blk_mq_make_queue_map(set);
+ if (!q->mq_map)
+ goto err_map;
+
+ blk_mq_realloc_hw_ctxs(set, q);
+ if (!q->nr_hw_queues)
+ goto err_hctxs;
INIT_WORK(&q->timeout_work, blk_mq_timeout_work);
blk_queue_rq_timeout(q, set->timeout ? set->timeout : 30 * HZ);
q->nr_queues = nr_cpu_ids;
- q->nr_hw_queues = set->nr_hw_queues;
- q->mq_map = map;
-
- q->queue_ctx = ctx;
- q->queue_hw_ctx = hctxs;
- q->mq_ops = set->ops;
q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT;
if (!(set->flags & BLK_MQ_F_SG_MERGE))
@@ -2050,9 +2066,6 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
blk_mq_init_cpu_queues(q, set->nr_hw_queues);
- if (blk_mq_init_hw_queues(q, set))
- goto err_hctxs;
-
get_online_cpus();
mutex_lock(&all_q_mutex);
@@ -2066,17 +2079,11 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
return q;
err_hctxs:
- kfree(map);
- for (i = 0; i < set->nr_hw_queues; i++) {
- if (!hctxs[i])
- break;
- free_cpumask_var(hctxs[i]->cpumask);
- kfree(hctxs[i]);
- }
+ kfree(q->mq_map);
err_map:
- kfree(hctxs);
+ kfree(q->queue_hw_ctx);
err_percpu:
- free_percpu(ctx);
+ free_percpu(q->queue_ctx);
return ERR_PTR(-ENOMEM);
}
EXPORT_SYMBOL(blk_mq_init_allocated_queue);
@@ -2284,9 +2291,13 @@ int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set)
set->nr_hw_queues = 1;
set->queue_depth = min(64U, set->queue_depth);
}
+ /*
+ * There is no use for more h/w queues than cpus.
+ */
+ if (set->nr_hw_queues > nr_cpu_ids)
+ set->nr_hw_queues = nr_cpu_ids;
- set->tags = kmalloc_node(set->nr_hw_queues *
- sizeof(struct blk_mq_tags *),
+ set->tags = kzalloc_node(nr_cpu_ids * sizeof(struct blk_mq_tags *),
GFP_KERNEL, set->numa_node);
if (!set->tags)
return -ENOMEM;
@@ -2309,7 +2320,7 @@ void blk_mq_free_tag_set(struct blk_mq_tag_set *set)
{
int i;
- for (i = 0; i < set->nr_hw_queues; i++) {
+ for (i = 0; i < nr_cpu_ids; i++) {
if (set->tags[i])
blk_mq_free_rq_map(set, set->tags[i], i);
}
@@ -2330,6 +2341,8 @@ int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr)
ret = 0;
queue_for_each_hw_ctx(q, hctx, i) {
+ if (!hctx->tags)
+ continue;
ret = blk_mq_tag_update_depth(hctx->tags, nr);
if (ret)
break;
@@ -2341,6 +2354,35 @@ int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr)
return ret;
}
+void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues)
+{
+ struct request_queue *q;
+
+ if (nr_hw_queues > nr_cpu_ids)
+ nr_hw_queues = nr_cpu_ids;
+ if (nr_hw_queues < 1 || nr_hw_queues == set->nr_hw_queues)
+ return;
+
+ list_for_each_entry(q, &set->tag_list, tag_set_list)
+ blk_mq_freeze_queue(q);
+
+ set->nr_hw_queues = nr_hw_queues;
+ list_for_each_entry(q, &set->tag_list, tag_set_list) {
+ blk_mq_realloc_hw_ctxs(set, q);
+
+ if (q->nr_hw_queues > 1)
+ blk_queue_make_request(q, blk_mq_make_request);
+ else
+ blk_queue_make_request(q, blk_sq_make_request);
+
+ blk_mq_queue_reinit(q, cpu_online_mask);
+ }
+
+ list_for_each_entry(q, &set->tag_list, tag_set_list)
+ blk_mq_unfreeze_queue(q);
+}
+EXPORT_SYMBOL_GPL(blk_mq_update_nr_hw_queues);
+
void blk_mq_disable_hotplug(void)
{
mutex_lock(&all_q_mutex);
diff --git a/block/blk-mq.h b/block/blk-mq.h
index eaede8e..9087b11 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -57,6 +57,7 @@ extern int blk_mq_hw_queue_to_node(unsigned int *map, unsigned int);
*/
extern int blk_mq_sysfs_register(struct request_queue *q);
extern void blk_mq_sysfs_unregister(struct request_queue *q);
+extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
extern void blk_mq_rq_timed_out(struct request *req, bool reserved);
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 1f9093e..e3c591d 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -632,6 +632,13 @@ static inline struct cfq_group *cfqg_parent(struct cfq_group *cfqg)
return pblkg ? blkg_to_cfqg(pblkg) : NULL;
}
+static inline bool cfqg_is_descendant(struct cfq_group *cfqg,
+ struct cfq_group *ancestor)
+{
+ return cgroup_is_descendant(cfqg_to_blkg(cfqg)->blkcg->css.cgroup,
+ cfqg_to_blkg(ancestor)->blkcg->css.cgroup);
+}
+
static inline void cfqg_get(struct cfq_group *cfqg)
{
return blkg_get(cfqg_to_blkg(cfqg));
@@ -758,6 +765,11 @@ static void cfqg_stats_xfer_dead(struct cfq_group *cfqg)
#else /* CONFIG_CFQ_GROUP_IOSCHED */
static inline struct cfq_group *cfqg_parent(struct cfq_group *cfqg) { return NULL; }
+static inline bool cfqg_is_descendant(struct cfq_group *cfqg,
+ struct cfq_group *ancestor)
+{
+ return true;
+}
static inline void cfqg_get(struct cfq_group *cfqg) { }
static inline void cfqg_put(struct cfq_group *cfqg) { }
@@ -2897,6 +2909,7 @@ static bool cfq_should_idle(struct cfq_data *cfqd, struct cfq_queue *cfqq)
static void cfq_arm_slice_timer(struct cfq_data *cfqd)
{
struct cfq_queue *cfqq = cfqd->active_queue;
+ struct cfq_rb_root *st = cfqq->service_tree;
struct cfq_io_cq *cic;
unsigned long sl, group_idle = 0;
@@ -2947,8 +2960,13 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd)
return;
}
- /* There are other queues in the group, don't do group idle */
- if (group_idle && cfqq->cfqg->nr_cfqq > 1)
+ /*
+ * There are other queues in the group or this is the only group and
+ * it has too big thinktime, don't do group idle.
+ */
+ if (group_idle &&
+ (cfqq->cfqg->nr_cfqq > 1 ||
+ cfq_io_thinktime_big(cfqd, &st->ttime, true)))
return;
cfq_mark_cfqq_wait_request(cfqq);
@@ -3947,16 +3965,27 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
if (rq_is_sync(rq) && !cfq_cfqq_sync(cfqq))
return true;
- if (new_cfqq->cfqg != cfqq->cfqg)
+ /*
+ * Treat ancestors of current cgroup the same way as current cgroup.
+ * For anybody else we disallow preemption to guarantee service
+ * fairness among cgroups.
+ */
+ if (!cfqg_is_descendant(cfqq->cfqg, new_cfqq->cfqg))
return false;
if (cfq_slice_used(cfqq))
return true;
+ /*
+ * Allow an RT request to pre-empt an ongoing non-RT cfqq timeslice.
+ */
+ if (cfq_class_rt(new_cfqq) && !cfq_class_rt(cfqq))
+ return true;
+
+ WARN_ON_ONCE(cfqq->ioprio_class != new_cfqq->ioprio_class);
/* Allow preemption only if we are idling on sync-noidle tree */
if (cfqd->serving_wl_type == SYNC_NOIDLE_WORKLOAD &&
cfqq_type(new_cfqq) == SYNC_NOIDLE_WORKLOAD &&
- new_cfqq->service_tree->count == 2 &&
RB_EMPTY_ROOT(&cfqq->sort_list))
return true;
@@ -3967,12 +3996,6 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
if ((rq->cmd_flags & REQ_PRIO) && !cfqq->prio_pending)
return true;
- /*
- * Allow an RT request to pre-empt an ongoing non-RT cfqq timeslice.
- */
- if (cfq_class_rt(new_cfqq) && !cfq_class_rt(cfqq))
- return true;
-
/* An idle queue should not be idle now for some reason */
if (RB_EMPTY_ROOT(&cfqq->sort_list) && !cfq_should_idle(cfqd, cfqq))
return true;
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