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authorLinus Torvalds <torvalds@linux-foundation.org>2017-09-09 12:49:01 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-09-09 12:49:01 -0700
commit126e76ffbf78d9e948b641aadb265d16c57f5a3d (patch)
tree656e7838f0ec057936b80e15a774911df05c6005 /block
parentfbd01410e89a66f346ba1b3c0161e1198449b746 (diff)
parent175206cf9ab63161dec74d9cd7f9992e062491f5 (diff)
downloadlwn-126e76ffbf78d9e948b641aadb265d16c57f5a3d.tar.gz
lwn-126e76ffbf78d9e948b641aadb265d16c57f5a3d.zip
Merge branch 'for-4.14/block-postmerge' of git://git.kernel.dk/linux-block
Pull followup block layer updates from Jens Axboe: "I ended up splitting the main pull request for this series into two, mainly because of clashes between NVMe fixes that went into 4.13 after the for-4.14 branches were split off. This pull request is mostly NVMe, but not exclusively. In detail, it contains: - Two pull request for NVMe changes from Christoph. Nothing new on the feature front, basically just fixes all over the map for the core bits, transport, rdma, etc. - Series from Bart, cleaning up various bits in the BFQ scheduler. - Series of bcache fixes, which has been lingering for a release or two. Coly sent this in, but patches from various people in this area. - Set of patches for BFQ from Paolo himself, updating both documentation and fixing some corner cases in performance. - Series from Omar, attempting to now get the 4k loop support correct. Our confidence level is higher this time. - Series from Shaohua for loop as well, improving O_DIRECT performance and fixing a use-after-free" * 'for-4.14/block-postmerge' of git://git.kernel.dk/linux-block: (74 commits) bcache: initialize dirty stripes in flash_dev_run() loop: set physical block size to logical block size bcache: fix bch_hprint crash and improve output bcache: Update continue_at() documentation bcache: silence static checker warning bcache: fix for gc and write-back race bcache: increase the number of open buckets bcache: Correct return value for sysfs attach errors bcache: correct cache_dirty_target in __update_writeback_rate() bcache: gc does not work when triggering by manual command bcache: Don't reinvent the wheel but use existing llist API bcache: do not subtract sectors_to_gc for bypassed IO bcache: fix sequential large write IO bypass bcache: Fix leak of bdev reference block/loop: remove unused field block/loop: fix use after free bfq: Use icq_to_bic() consistently bfq: Suppress compiler warnings about comparisons bfq: Check kstrtoul() return value bfq: Declare local functions static ...
Diffstat (limited to 'block')
-rw-r--r--block/bfq-cgroup.c18
-rw-r--r--block/bfq-iosched.c75
-rw-r--r--block/bfq-iosched.h4
-rw-r--r--block/bfq-wf2q.c91
4 files changed, 116 insertions, 72 deletions
diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c
index 78b2e0db4fb2..ceefb9a706d6 100644
--- a/block/bfq-cgroup.c
+++ b/block/bfq-cgroup.c
@@ -206,7 +206,7 @@ static void bfqg_get(struct bfq_group *bfqg)
bfqg->ref++;
}
-void bfqg_put(struct bfq_group *bfqg)
+static void bfqg_put(struct bfq_group *bfqg)
{
bfqg->ref--;
@@ -385,7 +385,7 @@ static struct bfq_group_data *blkcg_to_bfqgd(struct blkcg *blkcg)
return cpd_to_bfqgd(blkcg_to_cpd(blkcg, &blkcg_policy_bfq));
}
-struct blkcg_policy_data *bfq_cpd_alloc(gfp_t gfp)
+static struct blkcg_policy_data *bfq_cpd_alloc(gfp_t gfp)
{
struct bfq_group_data *bgd;
@@ -395,7 +395,7 @@ struct blkcg_policy_data *bfq_cpd_alloc(gfp_t gfp)
return &bgd->pd;
}
-void bfq_cpd_init(struct blkcg_policy_data *cpd)
+static void bfq_cpd_init(struct blkcg_policy_data *cpd)
{
struct bfq_group_data *d = cpd_to_bfqgd(cpd);
@@ -403,12 +403,12 @@ void bfq_cpd_init(struct blkcg_policy_data *cpd)
CGROUP_WEIGHT_DFL : BFQ_WEIGHT_LEGACY_DFL;
}
-void bfq_cpd_free(struct blkcg_policy_data *cpd)
+static void bfq_cpd_free(struct blkcg_policy_data *cpd)
{
kfree(cpd_to_bfqgd(cpd));
}
-struct blkg_policy_data *bfq_pd_alloc(gfp_t gfp, int node)
+static struct blkg_policy_data *bfq_pd_alloc(gfp_t gfp, int node)
{
struct bfq_group *bfqg;
@@ -426,7 +426,7 @@ struct blkg_policy_data *bfq_pd_alloc(gfp_t gfp, int node)
return &bfqg->pd;
}
-void bfq_pd_init(struct blkg_policy_data *pd)
+static void bfq_pd_init(struct blkg_policy_data *pd)
{
struct blkcg_gq *blkg = pd_to_blkg(pd);
struct bfq_group *bfqg = blkg_to_bfqg(blkg);
@@ -445,7 +445,7 @@ void bfq_pd_init(struct blkg_policy_data *pd)
bfqg->rq_pos_tree = RB_ROOT;
}
-void bfq_pd_free(struct blkg_policy_data *pd)
+static void bfq_pd_free(struct blkg_policy_data *pd)
{
struct bfq_group *bfqg = pd_to_bfqg(pd);
@@ -453,7 +453,7 @@ void bfq_pd_free(struct blkg_policy_data *pd)
bfqg_put(bfqg);
}
-void bfq_pd_reset_stats(struct blkg_policy_data *pd)
+static void bfq_pd_reset_stats(struct blkg_policy_data *pd)
{
struct bfq_group *bfqg = pd_to_bfqg(pd);
@@ -740,7 +740,7 @@ static void bfq_reparent_active_entities(struct bfq_data *bfqd,
* blkio already grabs the queue_lock for us, so no need to use
* RCU-based magic
*/
-void bfq_pd_offline(struct blkg_policy_data *pd)
+static void bfq_pd_offline(struct blkg_policy_data *pd)
{
struct bfq_service_tree *st;
struct bfq_group *bfqg = pd_to_bfqg(pd);
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index 6a7a26b6cec1..a4783da90ba8 100644
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -239,7 +239,7 @@ static int T_slow[2];
static int T_fast[2];
static int device_speed_thresh[2];
-#define RQ_BIC(rq) ((struct bfq_io_cq *) (rq)->elv.priv[0])
+#define RQ_BIC(rq) icq_to_bic((rq)->elv.priv[0])
#define RQ_BFQQ(rq) ((rq)->elv.priv[1])
struct bfq_queue *bic_to_bfqq(struct bfq_io_cq *bic, bool is_sync)
@@ -720,7 +720,7 @@ static void bfq_updated_next_req(struct bfq_data *bfqd,
entity->budget = new_budget;
bfq_log_bfqq(bfqd, bfqq, "updated next rq: new budget %lu",
new_budget);
- bfq_requeue_bfqq(bfqd, bfqq);
+ bfq_requeue_bfqq(bfqd, bfqq, false);
}
}
@@ -2563,7 +2563,7 @@ static void __bfq_bfqq_expire(struct bfq_data *bfqd, struct bfq_queue *bfqq)
bfq_del_bfqq_busy(bfqd, bfqq, true);
} else {
- bfq_requeue_bfqq(bfqd, bfqq);
+ bfq_requeue_bfqq(bfqd, bfqq, true);
/*
* Resort priority tree of potential close cooperators.
*/
@@ -3780,6 +3780,7 @@ bfq_set_next_ioprio_data(struct bfq_queue *bfqq, struct bfq_io_cq *bic)
default:
dev_err(bfqq->bfqd->queue->backing_dev_info->dev,
"bfq: bad prio class %d\n", ioprio_class);
+ /* fall through */
case IOPRIO_CLASS_NONE:
/*
* No prio set, inherit CPU scheduling settings.
@@ -4801,13 +4802,15 @@ static ssize_t bfq_var_show(unsigned int var, char *page)
return sprintf(page, "%u\n", var);
}
-static void bfq_var_store(unsigned long *var, const char *page)
+static int bfq_var_store(unsigned long *var, const char *page)
{
unsigned long new_val;
int ret = kstrtoul(page, 10, &new_val);
- if (ret == 0)
- *var = new_val;
+ if (ret)
+ return ret;
+ *var = new_val;
+ return 0;
}
#define SHOW_FUNCTION(__FUNC, __VAR, __CONV) \
@@ -4848,12 +4851,16 @@ static ssize_t \
__FUNC(struct elevator_queue *e, const char *page, size_t count) \
{ \
struct bfq_data *bfqd = e->elevator_data; \
- unsigned long uninitialized_var(__data); \
- bfq_var_store(&__data, (page)); \
- if (__data < (MIN)) \
- __data = (MIN); \
- else if (__data > (MAX)) \
- __data = (MAX); \
+ unsigned long __data, __min = (MIN), __max = (MAX); \
+ int ret; \
+ \
+ ret = bfq_var_store(&__data, (page)); \
+ if (ret) \
+ return ret; \
+ if (__data < __min) \
+ __data = __min; \
+ else if (__data > __max) \
+ __data = __max; \
if (__CONV == 1) \
*(__PTR) = msecs_to_jiffies(__data); \
else if (__CONV == 2) \
@@ -4876,12 +4883,16 @@ STORE_FUNCTION(bfq_slice_idle_store, &bfqd->bfq_slice_idle, 0, INT_MAX, 2);
static ssize_t __FUNC(struct elevator_queue *e, const char *page, size_t count)\
{ \
struct bfq_data *bfqd = e->elevator_data; \
- unsigned long uninitialized_var(__data); \
- bfq_var_store(&__data, (page)); \
- if (__data < (MIN)) \
- __data = (MIN); \
- else if (__data > (MAX)) \
- __data = (MAX); \
+ unsigned long __data, __min = (MIN), __max = (MAX); \
+ int ret; \
+ \
+ ret = bfq_var_store(&__data, (page)); \
+ if (ret) \
+ return ret; \
+ if (__data < __min) \
+ __data = __min; \
+ else if (__data > __max) \
+ __data = __max; \
*(__PTR) = (u64)__data * NSEC_PER_USEC; \
return count; \
}
@@ -4893,9 +4904,12 @@ static ssize_t bfq_max_budget_store(struct elevator_queue *e,
const char *page, size_t count)
{
struct bfq_data *bfqd = e->elevator_data;
- unsigned long uninitialized_var(__data);
+ unsigned long __data;
+ int ret;
- bfq_var_store(&__data, (page));
+ ret = bfq_var_store(&__data, (page));
+ if (ret)
+ return ret;
if (__data == 0)
bfqd->bfq_max_budget = bfq_calc_max_budget(bfqd);
@@ -4918,9 +4932,12 @@ static ssize_t bfq_timeout_sync_store(struct elevator_queue *e,
const char *page, size_t count)
{
struct bfq_data *bfqd = e->elevator_data;
- unsigned long uninitialized_var(__data);
+ unsigned long __data;
+ int ret;
- bfq_var_store(&__data, (page));
+ ret = bfq_var_store(&__data, (page));
+ if (ret)
+ return ret;
if (__data < 1)
__data = 1;
@@ -4938,9 +4955,12 @@ static ssize_t bfq_strict_guarantees_store(struct elevator_queue *e,
const char *page, size_t count)
{
struct bfq_data *bfqd = e->elevator_data;
- unsigned long uninitialized_var(__data);
+ unsigned long __data;
+ int ret;
- bfq_var_store(&__data, (page));
+ ret = bfq_var_store(&__data, (page));
+ if (ret)
+ return ret;
if (__data > 1)
__data = 1;
@@ -4957,9 +4977,12 @@ static ssize_t bfq_low_latency_store(struct elevator_queue *e,
const char *page, size_t count)
{
struct bfq_data *bfqd = e->elevator_data;
- unsigned long uninitialized_var(__data);
+ unsigned long __data;
+ int ret;
- bfq_var_store(&__data, (page));
+ ret = bfq_var_store(&__data, (page));
+ if (ret)
+ return ret;
if (__data > 1)
__data = 1;
diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h
index cc4ea8574483..ac0809c72c98 100644
--- a/block/bfq-iosched.h
+++ b/block/bfq-iosched.h
@@ -817,7 +817,6 @@ extern const int bfq_timeout;
struct bfq_queue *bic_to_bfqq(struct bfq_io_cq *bic, bool is_sync);
void bic_set_bfqq(struct bfq_io_cq *bic, struct bfq_queue *bfqq, bool is_sync);
struct bfq_data *bic_to_bfqd(struct bfq_io_cq *bic);
-void bfq_requeue_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq);
void bfq_pos_tree_add_move(struct bfq_data *bfqd, struct bfq_queue *bfqq);
void bfq_weights_tree_add(struct bfq_data *bfqd, struct bfq_entity *entity,
struct rb_root *root);
@@ -917,7 +916,8 @@ void __bfq_bfqd_reset_in_service(struct bfq_data *bfqd);
void bfq_deactivate_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq,
bool ins_into_idle_tree, bool expiration);
void bfq_activate_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq);
-void bfq_requeue_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq);
+void bfq_requeue_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq,
+ bool expiration);
void bfq_del_bfqq_busy(struct bfq_data *bfqd, struct bfq_queue *bfqq,
bool expiration);
void bfq_add_bfqq_busy(struct bfq_data *bfqd, struct bfq_queue *bfqq);
diff --git a/block/bfq-wf2q.c b/block/bfq-wf2q.c
index 911aa7431dbe..414ba686a847 100644
--- a/block/bfq-wf2q.c
+++ b/block/bfq-wf2q.c
@@ -44,7 +44,8 @@ static unsigned int bfq_class_idx(struct bfq_entity *entity)
BFQ_DEFAULT_GRP_CLASS - 1;
}
-static struct bfq_entity *bfq_lookup_next_entity(struct bfq_sched_data *sd);
+static struct bfq_entity *bfq_lookup_next_entity(struct bfq_sched_data *sd,
+ bool expiration);
static bool bfq_update_parent_budget(struct bfq_entity *next_in_service);
@@ -54,6 +55,8 @@ static bool bfq_update_parent_budget(struct bfq_entity *next_in_service);
* @new_entity: if not NULL, pointer to the entity whose activation,
* requeueing or repositionig triggered the invocation of
* this function.
+ * @expiration: id true, this function is being invoked after the
+ * expiration of the in-service entity
*
* This function is called to update sd->next_in_service, which, in
* its turn, may change as a consequence of the insertion or
@@ -72,19 +75,20 @@ static bool bfq_update_parent_budget(struct bfq_entity *next_in_service);
* entity.
*/
static bool bfq_update_next_in_service(struct bfq_sched_data *sd,
- struct bfq_entity *new_entity)
+ struct bfq_entity *new_entity,
+ bool expiration)
{
struct bfq_entity *next_in_service = sd->next_in_service;
bool parent_sched_may_change = false;
+ bool change_without_lookup = false;
/*
* If this update is triggered by the activation, requeueing
* or repositiong of an entity that does not coincide with
* sd->next_in_service, then a full lookup in the active tree
* can be avoided. In fact, it is enough to check whether the
- * just-modified entity has a higher priority than
- * sd->next_in_service, or, even if it has the same priority
- * as sd->next_in_service, is eligible and has a lower virtual
+ * just-modified entity has the same priority as
+ * sd->next_in_service, is eligible and has a lower virtual
* finish time than sd->next_in_service. If this compound
* condition holds, then the new entity becomes the new
* next_in_service. Otherwise no change is needed.
@@ -96,13 +100,12 @@ static bool bfq_update_next_in_service(struct bfq_sched_data *sd,
* set to true, and left as true if
* sd->next_in_service is NULL.
*/
- bool replace_next = true;
+ change_without_lookup = true;
/*
* If there is already a next_in_service candidate
- * entity, then compare class priorities or timestamps
- * to decide whether to replace sd->service_tree with
- * new_entity.
+ * entity, then compare timestamps to decide whether
+ * to replace sd->service_tree with new_entity.
*/
if (next_in_service) {
unsigned int new_entity_class_idx =
@@ -110,32 +113,26 @@ static bool bfq_update_next_in_service(struct bfq_sched_data *sd,
struct bfq_service_tree *st =
sd->service_tree + new_entity_class_idx;
- /*
- * For efficiency, evaluate the most likely
- * sub-condition first.
- */
- replace_next =
+ change_without_lookup =
(new_entity_class_idx ==
bfq_class_idx(next_in_service)
&&
!bfq_gt(new_entity->start, st->vtime)
&&
bfq_gt(next_in_service->finish,
- new_entity->finish))
- ||
- new_entity_class_idx <
- bfq_class_idx(next_in_service);
+ new_entity->finish));
}
- if (replace_next)
+ if (change_without_lookup)
next_in_service = new_entity;
- } else /* invoked because of a deactivation: lookup needed */
- next_in_service = bfq_lookup_next_entity(sd);
+ }
+
+ if (!change_without_lookup) /* lookup needed */
+ next_in_service = bfq_lookup_next_entity(sd, expiration);
- if (next_in_service) {
+ if (next_in_service)
parent_sched_may_change = !sd->next_in_service ||
bfq_update_parent_budget(next_in_service);
- }
sd->next_in_service = next_in_service;
@@ -1127,10 +1124,12 @@ static void __bfq_activate_requeue_entity(struct bfq_entity *entity,
* @requeue: true if this is a requeue, which implies that bfqq is
* being expired; thus ALL its ancestors stop being served and must
* therefore be requeued
+ * @expiration: true if this function is being invoked in the expiration path
+ * of the in-service queue
*/
static void bfq_activate_requeue_entity(struct bfq_entity *entity,
bool non_blocking_wait_rq,
- bool requeue)
+ bool requeue, bool expiration)
{
struct bfq_sched_data *sd;
@@ -1138,7 +1137,8 @@ static void bfq_activate_requeue_entity(struct bfq_entity *entity,
sd = entity->sched_data;
__bfq_activate_requeue_entity(entity, sd, non_blocking_wait_rq);
- if (!bfq_update_next_in_service(sd, entity) && !requeue)
+ if (!bfq_update_next_in_service(sd, entity, expiration) &&
+ !requeue)
break;
}
}
@@ -1194,6 +1194,8 @@ bool __bfq_deactivate_entity(struct bfq_entity *entity, bool ins_into_idle_tree)
* bfq_deactivate_entity - deactivate an entity representing a bfq_queue.
* @entity: the entity to deactivate.
* @ins_into_idle_tree: true if the entity can be put into the idle tree
+ * @expiration: true if this function is being invoked in the expiration path
+ * of the in-service queue
*/
static void bfq_deactivate_entity(struct bfq_entity *entity,
bool ins_into_idle_tree,
@@ -1222,7 +1224,7 @@ static void bfq_deactivate_entity(struct bfq_entity *entity,
* then, since entity has just been
* deactivated, a new one must be found.
*/
- bfq_update_next_in_service(sd, NULL);
+ bfq_update_next_in_service(sd, NULL, expiration);
if (sd->next_in_service || sd->in_service_entity) {
/*
@@ -1281,7 +1283,7 @@ static void bfq_deactivate_entity(struct bfq_entity *entity,
__bfq_requeue_entity(entity);
sd = entity->sched_data;
- if (!bfq_update_next_in_service(sd, entity) &&
+ if (!bfq_update_next_in_service(sd, entity, expiration) &&
!expiration)
/*
* next_in_service unchanged or not causing
@@ -1416,12 +1418,14 @@ __bfq_lookup_next_entity(struct bfq_service_tree *st, bool in_service)
/**
* bfq_lookup_next_entity - return the first eligible entity in @sd.
* @sd: the sched_data.
+ * @expiration: true if we are on the expiration path of the in-service queue
*
* This function is invoked when there has been a change in the trees
- * for sd, and we need know what is the new next entity after this
- * change.
+ * for sd, and we need to know what is the new next entity to serve
+ * after this change.
*/
-static struct bfq_entity *bfq_lookup_next_entity(struct bfq_sched_data *sd)
+static struct bfq_entity *bfq_lookup_next_entity(struct bfq_sched_data *sd,
+ bool expiration)
{
struct bfq_service_tree *st = sd->service_tree;
struct bfq_service_tree *idle_class_st = st + (BFQ_IOPRIO_CLASSES - 1);
@@ -1448,8 +1452,24 @@ static struct bfq_entity *bfq_lookup_next_entity(struct bfq_sched_data *sd)
* class, unless the idle class needs to be served.
*/
for (; class_idx < BFQ_IOPRIO_CLASSES; class_idx++) {
+ /*
+ * If expiration is true, then bfq_lookup_next_entity
+ * is being invoked as a part of the expiration path
+ * of the in-service queue. In this case, even if
+ * sd->in_service_entity is not NULL,
+ * sd->in_service_entiy at this point is actually not
+ * in service any more, and, if needed, has already
+ * been properly queued or requeued into the right
+ * tree. The reason why sd->in_service_entity is still
+ * not NULL here, even if expiration is true, is that
+ * sd->in_service_entiy is reset as a last step in the
+ * expiration path. So, if expiration is true, tell
+ * __bfq_lookup_next_entity that there is no
+ * sd->in_service_entity.
+ */
entity = __bfq_lookup_next_entity(st + class_idx,
- sd->in_service_entity);
+ sd->in_service_entity &&
+ !expiration);
if (entity)
break;
@@ -1562,7 +1582,7 @@ struct bfq_queue *bfq_get_next_queue(struct bfq_data *bfqd)
for_each_entity(entity) {
struct bfq_sched_data *sd = entity->sched_data;
- if (!bfq_update_next_in_service(sd, NULL))
+ if (!bfq_update_next_in_service(sd, NULL, false))
break;
}
@@ -1610,16 +1630,17 @@ void bfq_activate_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq)
struct bfq_entity *entity = &bfqq->entity;
bfq_activate_requeue_entity(entity, bfq_bfqq_non_blocking_wait_rq(bfqq),
- false);
+ false, false);
bfq_clear_bfqq_non_blocking_wait_rq(bfqq);
}
-void bfq_requeue_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq)
+void bfq_requeue_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq,
+ bool expiration)
{
struct bfq_entity *entity = &bfqq->entity;
bfq_activate_requeue_entity(entity, false,
- bfqq == bfqd->in_service_queue);
+ bfqq == bfqd->in_service_queue, expiration);
}
/*