diff options
Diffstat (limited to 'block')
34 files changed, 1808 insertions, 1065 deletions
diff --git a/block/Kconfig b/block/Kconfig index 1f2469a0123c..f7045aa47edb 100644 --- a/block/Kconfig +++ b/block/Kconfig @@ -74,7 +74,6 @@ config BLK_DEV_BSG config BLK_DEV_BSGLIB bool "Block layer SG support v4 helper lib" - default n select BLK_DEV_BSG select BLK_SCSI_REQUEST help @@ -107,7 +106,6 @@ config BLK_DEV_ZONED config BLK_DEV_THROTTLING bool "Block layer bio throttling support" depends on BLK_CGROUP=y - default n ---help--- Block layer bio throttling support. It can be used to limit the IO rate to a device. IO rate policies are per cgroup and @@ -119,7 +117,6 @@ config BLK_DEV_THROTTLING config BLK_DEV_THROTTLING_LOW bool "Block throttling .low limit interface support (EXPERIMENTAL)" depends on BLK_DEV_THROTTLING - default n ---help--- Add .low limit interface for block throttling. The low limit is a best effort limit to prioritize cgroups. Depending on the setting, the limit @@ -130,7 +127,6 @@ config BLK_DEV_THROTTLING_LOW config BLK_CMDLINE_PARSER bool "Block device command line partition parser" - default n ---help--- Enabling this option allows you to specify the partition layout from the kernel boot args. This is typically of use for embedded devices @@ -141,7 +137,6 @@ config BLK_CMDLINE_PARSER config BLK_WBT bool "Enable support for block device writeback throttling" - default n ---help--- Enabling this option enables the block layer to throttle buffered background writeback from the VM, making it more smooth and having @@ -152,7 +147,6 @@ config BLK_WBT config BLK_CGROUP_IOLATENCY bool "Enable support for latency based cgroup IO protection" depends on BLK_CGROUP=y - default n ---help--- Enabling this option enables the .latency interface for IO throttling. The IO controller will attempt to maintain average IO latencies below @@ -163,7 +157,6 @@ config BLK_CGROUP_IOLATENCY config BLK_WBT_SQ bool "Single queue writeback throttling" - default n depends on BLK_WBT ---help--- Enable writeback throttling by default on legacy single queue devices @@ -228,4 +221,7 @@ config BLK_MQ_RDMA depends on BLOCK && INFINIBAND default y +config BLK_PM + def_bool BLOCK && PM + source block/Kconfig.iosched diff --git a/block/Kconfig.iosched b/block/Kconfig.iosched index a4a8914bf7a4..f95a48b0d7b2 100644 --- a/block/Kconfig.iosched +++ b/block/Kconfig.iosched @@ -36,7 +36,6 @@ config IOSCHED_CFQ config CFQ_GROUP_IOSCHED bool "CFQ Group Scheduling support" depends on IOSCHED_CFQ && BLK_CGROUP - default n ---help--- Enable group IO scheduling in CFQ. @@ -82,7 +81,6 @@ config MQ_IOSCHED_KYBER config IOSCHED_BFQ tristate "BFQ I/O scheduler" - default n ---help--- BFQ I/O scheduler for BLK-MQ. BFQ distributes the bandwidth of of the device among all processes according to their weights, @@ -94,7 +92,6 @@ config IOSCHED_BFQ config BFQ_GROUP_IOSCHED bool "BFQ hierarchical scheduling support" depends on IOSCHED_BFQ && BLK_CGROUP - default n ---help--- Enable hierarchical scheduling in BFQ, using the blkio diff --git a/block/Makefile b/block/Makefile index 572b33f32c07..27eac600474f 100644 --- a/block/Makefile +++ b/block/Makefile @@ -37,3 +37,4 @@ obj-$(CONFIG_BLK_WBT) += blk-wbt.o obj-$(CONFIG_BLK_DEBUG_FS) += blk-mq-debugfs.o obj-$(CONFIG_BLK_DEBUG_FS_ZONED)+= blk-mq-debugfs-zoned.o obj-$(CONFIG_BLK_SED_OPAL) += sed-opal.o +obj-$(CONFIG_BLK_PM) += blk-pm.o diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index 653100fb719e..3a27d31fcda6 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -624,12 +624,13 @@ void bfq_pos_tree_add_move(struct bfq_data *bfqd, struct bfq_queue *bfqq) } /* - * Tell whether there are active queues or groups with differentiated weights. + * Tell whether there are active queues with different weights or + * active groups. */ -static bool bfq_differentiated_weights(struct bfq_data *bfqd) +static bool bfq_varied_queue_weights_or_active_groups(struct bfq_data *bfqd) { /* - * For weights to differ, at least one of the trees must contain + * For queue weights to differ, queue_weights_tree must contain * at least two nodes. */ return (!RB_EMPTY_ROOT(&bfqd->queue_weights_tree) && @@ -637,9 +638,7 @@ static bool bfq_differentiated_weights(struct bfq_data *bfqd) bfqd->queue_weights_tree.rb_node->rb_right) #ifdef CONFIG_BFQ_GROUP_IOSCHED ) || - (!RB_EMPTY_ROOT(&bfqd->group_weights_tree) && - (bfqd->group_weights_tree.rb_node->rb_left || - bfqd->group_weights_tree.rb_node->rb_right) + (bfqd->num_active_groups > 0 #endif ); } @@ -657,26 +656,25 @@ static bool bfq_differentiated_weights(struct bfq_data *bfqd) * 3) all active groups at the same level in the groups tree have the same * number of children. * - * Unfortunately, keeping the necessary state for evaluating exactly the - * above symmetry conditions would be quite complex and time-consuming. - * Therefore this function evaluates, instead, the following stronger - * sub-conditions, for which it is much easier to maintain the needed - * state: + * Unfortunately, keeping the necessary state for evaluating exactly + * the last two symmetry sub-conditions above would be quite complex + * and time consuming. Therefore this function evaluates, instead, + * only the following stronger two sub-conditions, for which it is + * much easier to maintain the needed state: * 1) all active queues have the same weight, - * 2) all active groups have the same weight, - * 3) all active groups have at most one active child each. - * In particular, the last two conditions are always true if hierarchical - * support and the cgroups interface are not enabled, thus no state needs - * to be maintained in this case. + * 2) there are no active groups. + * In particular, the last condition is always true if hierarchical + * support or the cgroups interface are not enabled, thus no state + * needs to be maintained in this case. */ static bool bfq_symmetric_scenario(struct bfq_data *bfqd) { - return !bfq_differentiated_weights(bfqd); + return !bfq_varied_queue_weights_or_active_groups(bfqd); } /* * If the weight-counter tree passed as input contains no counter for - * the weight of the input entity, then add that counter; otherwise just + * the weight of the input queue, then add that counter; otherwise just * increment the existing counter. * * Note that weight-counter trees contain few nodes in mostly symmetric @@ -687,25 +685,25 @@ static bool bfq_symmetric_scenario(struct bfq_data *bfqd) * In most scenarios, the rate at which nodes are created/destroyed * should be low too. */ -void bfq_weights_tree_add(struct bfq_data *bfqd, struct bfq_entity *entity, +void bfq_weights_tree_add(struct bfq_data *bfqd, struct bfq_queue *bfqq, struct rb_root *root) { + struct bfq_entity *entity = &bfqq->entity; struct rb_node **new = &(root->rb_node), *parent = NULL; /* - * Do not insert if the entity is already associated with a + * Do not insert if the queue is already associated with a * counter, which happens if: - * 1) the entity is associated with a queue, - * 2) a request arrival has caused the queue to become both + * 1) a request arrival has caused the queue to become both * non-weight-raised, and hence change its weight, and * backlogged; in this respect, each of the two events * causes an invocation of this function, - * 3) this is the invocation of this function caused by the + * 2) this is the invocation of this function caused by the * second event. This second invocation is actually useless, * and we handle this fact by exiting immediately. More * efficient or clearer solutions might possibly be adopted. */ - if (entity->weight_counter) + if (bfqq->weight_counter) return; while (*new) { @@ -715,7 +713,7 @@ void bfq_weights_tree_add(struct bfq_data *bfqd, struct bfq_entity *entity, parent = *new; if (entity->weight == __counter->weight) { - entity->weight_counter = __counter; + bfqq->weight_counter = __counter; goto inc_counter; } if (entity->weight < __counter->weight) @@ -724,66 +722,67 @@ void bfq_weights_tree_add(struct bfq_data *bfqd, struct bfq_entity *entity, new = &((*new)->rb_right); } - entity->weight_counter = kzalloc(sizeof(struct bfq_weight_counter), - GFP_ATOMIC); + bfqq->weight_counter = kzalloc(sizeof(struct bfq_weight_counter), + GFP_ATOMIC); /* * In the unlucky event of an allocation failure, we just - * exit. This will cause the weight of entity to not be - * considered in bfq_differentiated_weights, which, in its - * turn, causes the scenario to be deemed wrongly symmetric in - * case entity's weight would have been the only weight making - * the scenario asymmetric. On the bright side, no unbalance - * will however occur when entity becomes inactive again (the - * invocation of this function is triggered by an activation - * of entity). In fact, bfq_weights_tree_remove does nothing - * if !entity->weight_counter. + * exit. This will cause the weight of queue to not be + * considered in bfq_varied_queue_weights_or_active_groups, + * which, in its turn, causes the scenario to be deemed + * wrongly symmetric in case bfqq's weight would have been + * the only weight making the scenario asymmetric. On the + * bright side, no unbalance will however occur when bfqq + * becomes inactive again (the invocation of this function + * is triggered by an activation of queue). In fact, + * bfq_weights_tree_remove does nothing if + * !bfqq->weight_counter. */ - if (unlikely(!entity->weight_counter)) + if (unlikely(!bfqq->weight_counter)) return; - entity->weight_counter->weight = entity->weight; - rb_link_node(&entity->weight_counter->weights_node, parent, new); - rb_insert_color(&entity->weight_counter->weights_node, root); + bfqq->weight_counter->weight = entity->weight; + rb_link_node(&bfqq->weight_counter->weights_node, parent, new); + rb_insert_color(&bfqq->weight_counter->weights_node, root); inc_counter: - entity->weight_counter->num_active++; + bfqq->weight_counter->num_active++; } /* - * Decrement the weight counter associated with the entity, and, if the + * Decrement the weight counter associated with the queue, and, if the * counter reaches 0, remove the counter from the tree. * See the comments to the function bfq_weights_tree_add() for considerations * about overhead. */ void __bfq_weights_tree_remove(struct bfq_data *bfqd, - struct bfq_entity *entity, + struct bfq_queue *bfqq, struct rb_root *root) { - if (!entity->weight_counter) + if (!bfqq->weight_counter) return; - entity->weight_counter->num_active--; - if (entity->weight_counter->num_active > 0) + bfqq->weight_counter->num_active--; + if (bfqq->weight_counter->num_active > 0) goto reset_entity_pointer; - rb_erase(&entity->weight_counter->weights_node, root); - kfree(entity->weight_counter); + rb_erase(&bfqq->weight_counter->weights_node, root); + kfree(bfqq->weight_counter); reset_entity_pointer: - entity->weight_counter = NULL; + bfqq->weight_counter = NULL; } /* - * Invoke __bfq_weights_tree_remove on bfqq and all its inactive - * parent entities. + * Invoke __bfq_weights_tree_remove on bfqq and decrement the number + * of active groups for each queue's inactive parent entity. */ void bfq_weights_tree_remove(struct bfq_data *bfqd, struct bfq_queue *bfqq) { struct bfq_entity *entity = bfqq->entity.parent; - __bfq_weights_tree_remove(bfqd, &bfqq->entity, + __bfq_weights_tree_remove(bfqd, bfqq, &bfqd->queue_weights_tree); for_each_entity(entity) { @@ -797,17 +796,13 @@ void bfq_weights_tree_remove(struct bfq_data *bfqd, * next_in_service for details on why * in_service_entity must be checked too). * - * As a consequence, the weight of entity is - * not to be removed. In addition, if entity - * is active, then its parent entities are - * active as well, and thus their weights are - * not to be removed either. In the end, this - * loop must stop here. + * As a consequence, its parent entities are + * active as well, and thus this loop must + * stop here. */ break; } - __bfq_weights_tree_remove(bfqd, entity, - &bfqd->group_weights_tree); + bfqd->num_active_groups--; } } @@ -3182,6 +3177,13 @@ static unsigned long bfq_bfqq_softrt_next_start(struct bfq_data *bfqd, jiffies + nsecs_to_jiffies(bfqq->bfqd->bfq_slice_idle) + 4); } +static bool bfq_bfqq_injectable(struct bfq_queue *bfqq) +{ + return BFQQ_SEEKY(bfqq) && bfqq->wr_coeff == 1 && + blk_queue_nonrot(bfqq->bfqd->queue) && + bfqq->bfqd->hw_tag; +} + /** * bfq_bfqq_expire - expire a queue. * @bfqd: device owning the queue. @@ -3291,6 +3293,8 @@ void bfq_bfqq_expire(struct bfq_data *bfqd, if (ref == 1) /* bfqq is gone, no more actions on it */ return; + bfqq->injected_service = 0; + /* mark bfqq as waiting a request only if a bic still points to it */ if (!bfq_bfqq_busy(bfqq) && reason != BFQQE_BUDGET_TIMEOUT && @@ -3497,9 +3501,11 @@ static bool bfq_better_to_idle(struct bfq_queue *bfqq) * symmetric scenario where: * (i) each of these processes must get the same throughput as * the others; - * (ii) all these processes have the same I/O pattern - (either sequential or random). - * In fact, in such a scenario, the drive will tend to treat + * (ii) the I/O of each process has the same properties, in + * terms of locality (sequential or random), direction + * (reads or writes), request sizes, greediness + * (from I/O-bound to sporadic), and so on. + * In fact, in such a scenario, the drive tends to treat * the requests of each of these processes in about the same * way as the requests of the others, and thus to provide * each of these processes with about the same throughput @@ -3508,18 +3514,50 @@ static bool bfq_better_to_idle(struct bfq_queue *bfqq) * certainly needed to guarantee that bfqq receives its * assigned fraction of the device throughput (see [1] for * details). + * The problem is that idling may significantly reduce + * throughput with certain combinations of types of I/O and + * devices. An important example is sync random I/O, on flash + * storage with command queueing. So, unless bfqq falls in the + * above cases where idling also boosts throughput, it would + * be important to check conditions (i) and (ii) accurately, + * so as to avoid idling when not strictly needed for service + * guarantees. + * + * Unfortunately, it is extremely difficult to thoroughly + * check condition (ii). And, in case there are active groups, + * it becomes very difficult to check condition (i) too. In + * fact, if there are active groups, then, for condition (i) + * to become false, it is enough that an active group contains + * more active processes or sub-groups than some other active + * group. We address this issue with the following bi-modal + * behavior, implemented in the function + * bfq_symmetric_scenario(). * - * We address this issue by controlling, actually, only the - * symmetry sub-condition (i), i.e., provided that - * sub-condition (i) holds, idling is not performed, - * regardless of whether sub-condition (ii) holds. In other - * words, only if sub-condition (i) holds, then idling is + * If there are active groups, then the scenario is tagged as + * asymmetric, conservatively, without checking any of the + * conditions (i) and (ii). So the device is idled for bfqq. + * This behavior matches also the fact that groups are created + * exactly if controlling I/O (to preserve bandwidth and + * latency guarantees) is a primary concern. + * + * On the opposite end, if there are no active groups, then + * only condition (i) is actually controlled, i.e., provided + * that condition (i) holds, idling is not performed, + * regardless of whether condition (ii) holds. In other words, + * only if condition (i) does not hold, then idling is * allowed, and the device tends to be prevented from queueing - * many requests, possibly of several processes. The reason - * for not controlling also sub-condition (ii) is that we - * exploit preemption to preserve guarantees in case of - * symmetric scenarios, even if (ii) does not hold, as - * explained in the next two paragraphs. + * many requests, possibly of several processes. Since there + * are no active groups, then, to control condition (i) it is + * enough to check whether all active queues have the same + * weight. + * + * Not checking condition (ii) evidently exposes bfqq to the + * risk of getting less throughput than its fair share. + * However, for queues with the same weight, a further + * mechanism, preemption, mitigates or even eliminates this + * problem. And it does so without consequences on overall + * throughput. This mechanism and its benefits are explained + * in the next three paragraphs. * * Even if a queue, say Q, is expired when it remains idle, Q * can still preempt the new in-service queue if the next @@ -3533,11 +3571,7 @@ static bool bfq_better_to_idle(struct bfq_queue *bfqq) * idling allows the internal queues of the device to contain * many requests, and thus to reorder requests, we can rather * safely assume that the internal scheduler still preserves a - * minimum of mid-term fairness. The motivation for using - * preemption instead of idling is that, by not idling, - * service guarantees are preserved without minimally - * sacrificing throughput. In other words, both a high - * throughput and its desired distribution are obtained. + * minimum of mid-term fairness. * * More precisely, this preemption-based, idleless approach * provides fairness in terms of IOPS, and not sectors per @@ -3556,22 +3590,27 @@ static bool bfq_better_to_idle(struct bfq_queue *bfqq) * 1024/8 times as high as the service received by the other * queue. * - * On the other hand, device idling is performed, and thus - * pure sector-domain guarantees are provided, for the - * following queues, which are likely to need stronger - * throughput guarantees: weight-raised queues, and queues - * with a higher weight than other queues. When such queues - * are active, sub-condition (i) is false, which triggers - * device idling. + * The motivation for using preemption instead of idling (for + * queues with the same weight) is that, by not idling, + * service guarantees are preserved (completely or at least in + * part) without minimally sacrificing throughput. And, if + * there is no active group, then the primary expectation for + * this device is probably a high throughput. * - * According to the above considerations, the next variable is - * true (only) if sub-condition (i) holds. To compute the - * value of this variable, we not only use the return value of - * the function bfq_symmetric_scenario(), but also check - * whether bfqq is being weight-raised, because - * bfq_symmetric_scenario() does not take into account also - * weight-raised queues (see comments on - * bfq_weights_tree_add()). + * We are now left only with explaining the additional + * compound condition that is checked below for deciding + * whether the scenario is asymmetric. To explain this + * compound condition, we need to add that the function + * bfq_symmetric_scenario checks the weights of only + * non-weight-raised queues, for efficiency reasons (see + * comments on bfq_weights_tree_add()). Then the fact that + * bfqq is weight-raised is checked explicitly here. More + * precisely, the compound condition below takes into account + * also the fact that, even if bfqq is being weight-raised, + * the scenario is still symmetric if all active queues happen + * to be weight-raised. Actually, we should be even more + * precise here, and differentiate between interactive weight + * raising and soft real-time weight raising. * * As a side note, it is worth considering that the above * device-idling countermeasures may however fail in the @@ -3583,7 +3622,8 @@ static bool bfq_better_to_idle(struct bfq_queue *bfqq) * to let requests be served in the desired order until all * the requests already queued in the device have been served. */ - asymmetric_scenario = bfqq->wr_coeff > 1 || + asymmetric_scenario = (bfqq->wr_coeff > 1 && + bfqd->wr_busy_queues < bfqd->busy_queues) || !bfq_symmetric_scenario(bfqd); /* @@ -3629,6 +3669,30 @@ static bool bfq_bfqq_must_idle(struct bfq_queue *bfqq) return RB_EMPTY_ROOT(&bfqq->sort_list) && bfq_better_to_idle(bfqq); } +static struct bfq_queue *bfq_choose_bfqq_for_injection(struct bfq_data *bfqd) +{ + struct bfq_queue *bfqq; + + /* + * A linear search; but, with a high probability, very few + * steps are needed to find a candidate queue, i.e., a queue + * with enough budget left for its next request. In fact: + * - BFQ dynamically updates the budget of every queue so as + * to accommodate the expected backlog of the queue; + * - if a queue gets all its requests dispatched as injected + * service, then the queue is removed from the active list + * (and re-added only if it gets new requests, but with + * enough budget for its new backlog). + */ + list_for_each_entry(bfqq, &bfqd->active_list, bfqq_list) + if (!RB_EMPTY_ROOT(&bfqq->sort_list) && + bfq_serv_to_charge(bfqq->next_rq, bfqq) <= + bfq_bfqq_budget_left(bfqq)) + return bfqq; + + return NULL; +} + /* * Select a queue for service. If we have a current queue in service, * check whether to continue servicing it, or retrieve and set a new one. @@ -3710,10 +3774,19 @@ check_queue: * No requests pending. However, if the in-service queue is idling * for a new request, or has requests waiting for a completion and * may idle after their completion, then keep it anyway. + * + * Yet, to boost throughput, inject service from other queues if + * possible. */ if (bfq_bfqq_wait_request(bfqq) || (bfqq->dispatched != 0 && bfq_better_to_idle(bfqq))) { - bfqq = NULL; + if (bfq_bfqq_injectable(bfqq) && + bfqq->injected_service * bfqq->inject_coeff < + bfqq->entity.service * 10) + bfqq = bfq_choose_bfqq_for_injection(bfqd); + else + bfqq = NULL; + goto keep_queue; } @@ -3803,6 +3876,14 @@ static struct request *bfq_dispatch_rq_from_bfqq(struct bfq_data *bfqd, bfq_dispatch_remove(bfqd->queue, rq); + if (bfqq != bfqd->in_service_queue) { + if (likely(bfqd->in_service_queue)) + bfqd->in_service_queue->injected_service += + bfq_serv_to_charge(rq, bfqq); + + goto return_rq; + } + /* * If weight raising has to terminate for bfqq, then next * function causes an immediate update of bfqq's weight, @@ -3821,13 +3902,12 @@ static struct request *bfq_dispatch_rq_from_bfqq(struct bfq_data *bfqd, * belongs to CLASS_IDLE and other queues are waiting for * service. */ - if (bfqd->busy_queues > 1 && bfq_class_idle(bfqq)) - goto expire; - - return rq; + if (!(bfqd->busy_queues > 1 && bfq_class_idle(bfqq))) + goto return_rq; -expire: bfq_bfqq_expire(bfqd, bfqq, false, BFQQE_BUDGET_EXHAUSTED); + +return_rq: return rq; } @@ -4232,6 +4312,13 @@ static void bfq_init_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq, bfq_mark_bfqq_has_short_ttime(bfqq); bfq_mark_bfqq_sync(bfqq); bfq_mark_bfqq_just_created(bfqq); + /* + * Aggressively inject a lot of service: up to 90%. + * This coefficient remains constant during bfqq life, + * but this behavior might be changed, after enough + * testing and tuning. + */ + bfqq->inject_coeff = 1; } else bfq_clear_bfqq_sync(bfqq); @@ -5330,7 +5417,7 @@ static int bfq_init_queue(struct request_queue *q, struct elevator_type *e) bfqd->idle_slice_timer.function = bfq_idle_slice_timer; bfqd->queue_weights_tree = RB_ROOT; - bfqd->group_weights_tree = RB_ROOT; + bfqd->num_active_groups = 0; INIT_LIST_HEAD(&bfqd->active_list); INIT_LIST_HEAD(&bfqd->idle_list); diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h index a8a2e5aca4d4..77651d817ecd 100644 --- a/block/bfq-iosched.h +++ b/block/bfq-iosched.h @@ -108,15 +108,14 @@ struct bfq_sched_data { }; /** - * struct bfq_weight_counter - counter of the number of all active entities + * struct bfq_weight_counter - counter of the number of all active queues * with a given weight. */ struct bfq_weight_counter { - unsigned int weight; /* weight of the entities this counter refers to */ - unsigned int num_active; /* nr of active entities with this weight */ + unsigned int weight; /* weight of the queues this counter refers to */ + unsigned int num_active; /* nr of active queues with this weight */ /* - * Weights tree member (see bfq_data's @queue_weights_tree and - * @group_weights_tree) + * Weights tree member (see bfq_data's @queue_weights_tree) */ struct rb_node weights_node; }; @@ -151,8 +150,6 @@ struct bfq_weight_counter { struct bfq_entity { /* service_tree member */ struct rb_node rb_node; - /* pointer to the weight counter associated with this entity */ - struct bfq_weight_counter *weight_counter; /* * Flag, true if the entity is on a tree (either the active or @@ -266,6 +263,9 @@ struct bfq_queue { /* entity representing this queue in the scheduler */ struct bfq_entity entity; + /* pointer to the weight counter associated with this entity */ + struct bfq_weight_counter *weight_counter; + /* maximum budget allowed from the feedback mechanism */ int max_budget; /* budget expiration (in jiffies) */ @@ -351,6 +351,32 @@ struct bfq_queue { unsigned long split_time; /* time of last split */ unsigned long first_IO_time; /* time of first I/O for this queue */ + + /* max service rate measured so far */ + u32 max_service_rate; + /* + * Ratio between the service received by bfqq while it is in + * service, and the cumulative service (of requests of other + * queues) that may be injected while bfqq is empty but still + * in service. To increase precision, the coefficient is + * measured in tenths of unit. Here are some example of (1) + * ratios, (2) resulting percentages of service injected + * w.r.t. to the total service dispatched while bfqq is in + * service, and (3) corresponding values of the coefficient: + * 1 (50%) -> 10 + * 2 (33%) -> 20 + * 10 (9%) -> 100 + * 9.9 (9%) -> 99 + * 1.5 (40%) -> 15 + * 0.5 (66%) -> 5 + * 0.1 (90%) -> 1 + * + * So, if the coefficient is lower than 10, then + * injected service is more than bfqq service. + */ + unsigned int inject_coeff; + /* amount of service injected in current service slot */ + unsigned int injected_service; }; /** @@ -423,14 +449,9 @@ struct bfq_data { */ struct rb_root queue_weights_tree; /* - * rbtree of non-queue @bfq_entity weight counters, sorted by - * weight. Used to keep track of whether all @bfq_groups have - * the same weight. The tree contains one counter for each - * distinct weight associated to some active @bfq_group (see - * the comments to the functions bfq_weights_tree_[add|remove] - * for further details). + * number of groups with requests still waiting for completion */ - struct rb_root group_weights_tree; + unsigned int num_active_groups; /* * Number of bfq_queues containing requests (including the @@ -825,10 +846,10 @@ 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_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, +void bfq_weights_tree_add(struct bfq_data *bfqd, struct bfq_queue *bfqq, struct rb_root *root); void __bfq_weights_tree_remove(struct bfq_data *bfqd, - struct bfq_entity *entity, + struct bfq_queue *bfqq, struct rb_root *root); void bfq_weights_tree_remove(struct bfq_data *bfqd, struct bfq_queue *bfqq); diff --git a/block/bfq-wf2q.c b/block/bfq-wf2q.c index ae52bff43ce4..4b0d5fb69160 100644 --- a/block/bfq-wf2q.c +++ b/block/bfq-wf2q.c @@ -788,25 +788,23 @@ __bfq_entity_update_weight_prio(struct bfq_service_tree *old_st, new_weight = entity->orig_weight * (bfqq ? bfqq->wr_coeff : 1); /* - * If the weight of the entity changes, remove the entity - * from its old weight counter (if there is a counter - * associated with the entity), and add it to the counter - * associated with its new weight. + * If the weight of the entity changes, and the entity is a + * queue, remove the entity from its old weight counter (if + * there is a counter associated with the entity). */ - if (prev_weight != new_weight) { - root = bfqq ? &bfqd->queue_weights_tree : - &bfqd->group_weights_tree; - __bfq_weights_tree_remove(bfqd, entity, root); + if (prev_weight != new_weight && bfqq) { + root = &bfqd->queue_weights_tree; + __bfq_weights_tree_remove(bfqd, bfqq, root); } entity->weight = new_weight; /* - * Add the entity to its weights tree only if it is - * not associated with a weight-raised queue. + * Add the entity, if it is not a weight-raised queue, + * to the counter associated with its new weight. */ - if (prev_weight != new_weight && - (bfqq ? bfqq->wr_coeff == 1 : 1)) + if (prev_weight != new_weight && bfqq && bfqq->wr_coeff == 1) { /* If we get here, root has been initialized. */ - bfq_weights_tree_add(bfqd, entity, root); + bfq_weights_tree_add(bfqd, bfqq, root); + } new_st->wsum += entity->weight; @@ -1012,9 +1010,9 @@ static void __bfq_activate_entity(struct bfq_entity *entity, if (!bfq_entity_to_bfqq(entity)) { /* bfq_group */ struct bfq_group *bfqg = container_of(entity, struct bfq_group, entity); + struct bfq_data *bfqd = bfqg->bfqd; - bfq_weights_tree_add(bfqg->bfqd, entity, - &bfqd->group_weights_tree); + bfqd->num_active_groups++; } #endif @@ -1181,10 +1179,17 @@ bool __bfq_deactivate_entity(struct bfq_entity *entity, bool ins_into_idle_tree) st = bfq_entity_service_tree(entity); is_in_service = entity == sd->in_service_entity; - if (is_in_service) { - bfq_calc_finish(entity, entity->service); + bfq_calc_finish(entity, entity->service); + + if (is_in_service) sd->in_service_entity = NULL; - } + else + /* + * Non in-service entity: nobody will take care of + * resetting its service counter on expiration. Do it + * now. + */ + entity->service = 0; if (entity->tree == &st->active) bfq_active_extract(st, entity); @@ -1685,7 +1690,7 @@ void bfq_add_bfqq_busy(struct bfq_data *bfqd, struct bfq_queue *bfqq) if (!bfqq->dispatched) if (bfqq->wr_coeff == 1) - bfq_weights_tree_add(bfqd, &bfqq->entity, + bfq_weights_tree_add(bfqd, bfqq, &bfqd->queue_weights_tree); if (bfqq->wr_coeff > 1) diff --git a/block/bio-integrity.c b/block/bio-integrity.c index 67b5fb861a51..290af497997b 100644 --- a/block/bio-integrity.c +++ b/block/bio-integrity.c @@ -306,6 +306,8 @@ bool bio_integrity_prep(struct bio *bio) if (bio_data_dir(bio) == WRITE) { bio_integrity_process(bio, &bio->bi_iter, bi->profile->generate_fn); + } else { + bip->bio_iter = bio->bi_iter; } return true; @@ -331,20 +333,14 @@ static void bio_integrity_verify_fn(struct work_struct *work) container_of(work, struct bio_integrity_payload, bip_work); struct bio *bio = bip->bip_bio; struct blk_integrity *bi = blk_get_integrity(bio->bi_disk); - struct bvec_iter iter = bio->bi_iter; /* * At the moment verify is called bio's iterator was advanced * during split and completion, we need to rewind iterator to * it's original position. */ - if (bio_rewind_iter(bio, &iter, iter.bi_done)) { - bio->bi_status = bio_integrity_process(bio, &iter, - bi->profile->verify_fn); - } else { - bio->bi_status = BLK_STS_IOERR; - } - + bio->bi_status = bio_integrity_process(bio, &bip->bio_iter, + bi->profile->verify_fn); bio_integrity_free(bio); bio_endio(bio); } diff --git a/block/bio.c b/block/bio.c index 0093bed81c0e..d5368a445561 100644 --- a/block/bio.c +++ b/block/bio.c @@ -729,7 +729,7 @@ int bio_add_pc_page(struct request_queue *q, struct bio *bio, struct page } /* If we may be able to merge these biovecs, force a recount */ - if (bio->bi_vcnt > 1 && (BIOVEC_PHYS_MERGEABLE(bvec-1, bvec))) + if (bio->bi_vcnt > 1 && biovec_phys_mergeable(q, bvec - 1, bvec)) bio_clear_flag(bio, BIO_SEG_VALID); done: @@ -827,6 +827,8 @@ int bio_add_page(struct bio *bio, struct page *page, } EXPORT_SYMBOL(bio_add_page); +#define PAGE_PTRS_PER_BVEC (sizeof(struct bio_vec) / sizeof(struct page *)) + /** * __bio_iov_iter_get_pages - pin user or kernel pages and add them to a bio * @bio: bio to add pages to @@ -839,38 +841,35 @@ EXPORT_SYMBOL(bio_add_page); */ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) { - unsigned short nr_pages = bio->bi_max_vecs - bio->bi_vcnt, idx; + unsigned short nr_pages = bio->bi_max_vecs - bio->bi_vcnt; + unsigned short entries_left = bio->bi_max_vecs - bio->bi_vcnt; struct bio_vec *bv = bio->bi_io_vec + bio->bi_vcnt; struct page **pages = (struct page **)bv; + ssize_t size, left; + unsigned len, i; size_t offset; - ssize_t size; + + /* + * Move page array up in the allocated memory for the bio vecs as far as + * possible so that we can start filling biovecs from the beginning + * without overwriting the temporary page array. + */ + BUILD_BUG_ON(PAGE_PTRS_PER_BVEC < 2); + pages += entries_left * (PAGE_PTRS_PER_BVEC - 1); size = iov_iter_get_pages(iter, pages, LONG_MAX, nr_pages, &offset); if (unlikely(size <= 0)) return size ? size : -EFAULT; - idx = nr_pages = (size + offset + PAGE_SIZE - 1) / PAGE_SIZE; - /* - * Deep magic below: We need to walk the pinned pages backwards - * because we are abusing the space allocated for the bio_vecs - * for the page array. Because the bio_vecs are larger than the - * page pointers by definition this will always work. But it also - * means we can't use bio_add_page, so any changes to it's semantics - * need to be reflected here as well. - */ - bio->bi_iter.bi_size += size; - bio->bi_vcnt += nr_pages; + for (left = size, i = 0; left > 0; left -= len, i++) { + struct page *page = pages[i]; - while (idx--) { - bv[idx].bv_page = pages[idx]; - bv[idx].bv_len = PAGE_SIZE; - bv[idx].bv_offset = 0; + len = min_t(size_t, PAGE_SIZE - offset, left); + if (WARN_ON_ONCE(bio_add_page(bio, page, len, offset) != len)) + return -EINVAL; + offset = 0; } - bv[0].bv_offset += offset; - bv[0].bv_len -= offset; - bv[nr_pages - 1].bv_len -= nr_pages * PAGE_SIZE - offset - size; - iov_iter_advance(iter, size); return 0; } @@ -1255,7 +1254,7 @@ struct bio *bio_copy_user_iov(struct request_queue *q, /* * success */ - if (((iter->type & WRITE) && (!map_data || !map_data->null_mapped)) || + if ((iov_iter_rw(iter) == WRITE && (!map_data || !map_data->null_mapped)) || (map_data && map_data->from_user)) { ret = bio_copy_from_iter(bio, iter); if (ret) @@ -1807,7 +1806,6 @@ struct bio *bio_split(struct bio *bio, int sectors, bio_integrity_trim(split); bio_advance(bio, split->bi_iter.bi_size); - bio->bi_iter.bi_done = 0; if (bio_flagged(bio, BIO_TRACE_COMPLETION)) bio_set_flag(split, BIO_TRACE_COMPLETION); diff --git a/block/blk-core.c b/block/blk-core.c index cff0a60ee200..ce12515f9b9b 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -42,6 +42,7 @@ #include "blk.h" #include "blk-mq.h" #include "blk-mq-sched.h" +#include "blk-pm.h" #include "blk-rq-qos.h" #ifdef CONFIG_DEBUG_FS @@ -421,24 +422,25 @@ void blk_sync_queue(struct request_queue *q) EXPORT_SYMBOL(blk_sync_queue); /** - * blk_set_preempt_only - set QUEUE_FLAG_PREEMPT_ONLY + * blk_set_pm_only - increment pm_only counter * @q: request queue pointer - * - * Returns the previous value of the PREEMPT_ONLY flag - 0 if the flag was not - * set and 1 if the flag was already set. */ -int blk_set_preempt_only(struct request_queue *q) +void blk_set_pm_only(struct request_queue *q) { - return blk_queue_flag_test_and_set(QUEUE_FLAG_PREEMPT_ONLY, q); + atomic_inc(&q->pm_only); } -EXPORT_SYMBOL_GPL(blk_set_preempt_only); +EXPORT_SYMBOL_GPL(blk_set_pm_only); -void blk_clear_preempt_only(struct request_queue *q) +void blk_clear_pm_only(struct request_queue *q) { - blk_queue_flag_clear(QUEUE_FLAG_PREEMPT_ONLY, q); - wake_up_all(&q->mq_freeze_wq); + int pm_only; + + pm_only = atomic_dec_return(&q->pm_only); + WARN_ON_ONCE(pm_only < 0); + if (pm_only == 0) + wake_up_all(&q->mq_freeze_wq); } -EXPORT_SYMBOL_GPL(blk_clear_preempt_only); +EXPORT_SYMBOL_GPL(blk_clear_pm_only); /** * __blk_run_queue_uncond - run a queue whether or not it has been stopped @@ -783,6 +785,9 @@ void blk_cleanup_queue(struct request_queue *q) * prevent that q->request_fn() gets invoked after draining finished. */ blk_freeze_queue(q); + + rq_qos_exit(q); + spin_lock_irq(lock); queue_flag_set(QUEUE_FLAG_DEAD, q); spin_unlock_irq(lock); @@ -917,7 +922,7 @@ EXPORT_SYMBOL(blk_alloc_queue); */ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags) { - const bool preempt = flags & BLK_MQ_REQ_PREEMPT; + const bool pm = flags & BLK_MQ_REQ_PREEMPT; while (true) { bool success = false; @@ -925,11 +930,11 @@ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags) rcu_read_lock(); if (percpu_ref_tryget_live(&q->q_usage_counter)) { /* - * The code that sets the PREEMPT_ONLY flag is - * responsible for ensuring that that flag is globally - * visible before the queue is unfrozen. + * The code that increments the pm_only counter is + * responsible for ensuring that that counter is + * globally visible before the queue is unfrozen. */ - if (preempt || !blk_queue_preempt_only(q)) { + if (pm || !blk_queue_pm_only(q)) { success = true; } else { percpu_ref_put(&q->q_usage_counter); @@ -954,7 +959,8 @@ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags) wait_event(q->mq_freeze_wq, (atomic_read(&q->mq_freeze_depth) == 0 && - (preempt || !blk_queue_preempt_only(q))) || + (pm || (blk_pm_request_resume(q), + !blk_queue_pm_only(q)))) || blk_queue_dying(q)); if (blk_queue_dying(q)) return -ENODEV; @@ -1051,8 +1057,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id, mutex_init(&q->sysfs_lock); spin_lock_init(&q->__queue_lock); - if (!q->mq_ops) - q->queue_lock = lock ? : &q->__queue_lock; + q->queue_lock = lock ? : &q->__queue_lock; /* * A queue starts its life with bypass turned on to avoid @@ -1160,7 +1165,7 @@ int blk_init_allocated_queue(struct request_queue *q) { WARN_ON_ONCE(q->mq_ops); - q->fq = blk_alloc_flush_queue(q, NUMA_NO_NODE, q->cmd_size); + q->fq = blk_alloc_flush_queue(q, NUMA_NO_NODE, q->cmd_size, GFP_KERNEL); if (!q->fq) return -ENOMEM; @@ -1726,16 +1731,6 @@ void part_round_stats(struct request_queue *q, int cpu, struct hd_struct *part) } EXPORT_SYMBOL_GPL(part_round_stats); -#ifdef CONFIG_PM -static void blk_pm_put_request(struct request *rq) -{ - if (rq->q->dev && !(rq->rq_flags & RQF_PM) && !--rq->q->nr_pending) - pm_runtime_mark_last_busy(rq->q->dev); -} -#else -static inline void blk_pm_put_request(struct request *rq) {} -#endif - void __blk_put_request(struct request_queue *q, struct request *req) { req_flags_t rq_flags = req->rq_flags; @@ -1752,6 +1747,7 @@ void __blk_put_request(struct request_queue *q, struct request *req) blk_req_zone_write_unlock(req); blk_pm_put_request(req); + blk_pm_mark_last_busy(req); elv_completed_request(q, req); @@ -2307,7 +2303,6 @@ generic_make_request_checks(struct bio *bio) if (!q->limits.max_write_same_sectors) goto not_supported; break; - case REQ_OP_ZONE_REPORT: case REQ_OP_ZONE_RESET: if (!blk_queue_is_zoned(q)) goto not_supported; @@ -2750,30 +2745,6 @@ void blk_account_io_done(struct request *req, u64 now) } } -#ifdef CONFIG_PM -/* - * Don't process normal requests when queue is suspended - * or in the process of suspending/resuming - */ -static bool blk_pm_allow_request(struct request *rq) -{ - switch (rq->q->rpm_status) { - case RPM_RESUMING: - case RPM_SUSPENDING: - return rq->rq_flags & RQF_PM; - case RPM_SUSPENDED: - return false; - default: - return true; - } -} -#else -static bool blk_pm_allow_request(struct request *rq) -{ - return true; -} -#endif - void blk_account_io_start(struct request *rq, bool new_io) { struct hd_struct *part; @@ -2819,11 +2790,14 @@ static struct request *elv_next_request(struct request_queue *q) while (1) { list_for_each_entry(rq, &q->queue_head, queuelist) { - if (blk_pm_allow_request(rq)) - return rq; - - if (rq->rq_flags & RQF_SOFTBARRIER) - break; +#ifdef CONFIG_PM + /* + * If a request gets queued in state RPM_SUSPENDED + * then that's a kernel bug. + */ + WARN_ON_ONCE(q->rpm_status == RPM_SUSPENDED); +#endif + return rq; } /* @@ -3755,191 +3729,6 @@ void blk_finish_plug(struct blk_plug *plug) } EXPORT_SYMBOL(blk_finish_plug); -#ifdef CONFIG_PM -/** - * blk_pm_runtime_init - Block layer runtime PM initialization routine - * @q: the queue of the device - * @dev: the device the queue belongs to - * - * Description: - * Initialize runtime-PM-related fields for @q and start auto suspend for - * @dev. Drivers that want to take advantage of request-based runtime PM - * should call this function after @dev has been initialized, and its - * request queue @q has been allocated, and runtime PM for it can not happen - * yet(either due to disabled/forbidden or its usage_count > 0). In most - * cases, driver should call this function before any I/O has taken place. - * - * This function takes care of setting up using auto suspend for the device, - * the autosuspend delay is set to -1 to make runtime suspend impossible - * until an updated value is either set by user or by driver. Drivers do - * not need to touch other autosuspend settings. - * - * The block layer runtime PM is request based, so only works for drivers - * that use request as their IO unit instead of those directly use bio's. - */ -void blk_pm_runtime_init(struct request_queue *q, struct device *dev) -{ - /* Don't enable runtime PM for blk-mq until it is ready */ - if (q->mq_ops) { - pm_runtime_disable(dev); - return; - } - - q->dev = dev; - q->rpm_status = RPM_ACTIVE; - pm_runtime_set_autosuspend_delay(q->dev, -1); - pm_runtime_use_autosuspend(q->dev); -} -EXPORT_SYMBOL(blk_pm_runtime_init); - -/** - * blk_pre_runtime_suspend - Pre runtime suspend check - * @q: the queue of the device - * - * Description: - * This function will check if runtime suspend is allowed for the device - * by examining if there are any requests pending in the queue. If there - * are requests pending, the device can not be runtime suspended; otherwise, - * the queue's status will be updated to SUSPENDING and the driver can - * proceed to suspend the device. - * - * For the not allowed case, we mark last busy for the device so that - * runtime PM core will try to autosuspend it some time later. - * - * This function should be called near the start of the device's - * runtime_suspend callback. - * - * Return: - * 0 - OK to runtime suspend the device - * -EBUSY - Device should not be runtime suspended - */ -int blk_pre_runtime_suspend(struct request_queue *q) -{ - int ret = 0; - - if (!q->dev) - return ret; - - spin_lock_irq(q->queue_lock); - if (q->nr_pending) { - ret = -EBUSY; - pm_runtime_mark_last_busy(q->dev); - } else { - q->rpm_status = RPM_SUSPENDING; - } - spin_unlock_irq(q->queue_lock); - return ret; -} -EXPORT_SYMBOL(blk_pre_runtime_suspend); - -/** - * blk_post_runtime_suspend - Post runtime suspend processing - * @q: the queue of the device - * @err: return value of the device's runtime_suspend function - * - * Description: - * Update the queue's runtime status according to the return value of the - * device's runtime suspend function and mark last busy for the device so - * that PM core will try to auto suspend the device at a later time. - * - * This function should be called near the end of the device's - * runtime_suspend callback. - */ -void blk_post_runtime_suspend(struct request_queue *q, int err) -{ - if (!q->dev) - return; - - spin_lock_irq(q->queue_lock); - if (!err) { - q->rpm_status = RPM_SUSPENDED; - } else { - q->rpm_status = RPM_ACTIVE; - pm_runtime_mark_last_busy(q->dev); - } - spin_unlock_irq(q->queue_lock); -} -EXPORT_SYMBOL(blk_post_runtime_suspend); - -/** - * blk_pre_runtime_resume - Pre runtime resume processing - * @q: the queue of the device - * - * Description: - * Update the queue's runtime status to RESUMING in preparation for the - * runtime resume of the device. - * - * This function should be called near the start of the device's - * runtime_resume callback. - */ -void blk_pre_runtime_resume(struct request_queue *q) -{ - if (!q->dev) - return; - - spin_lock_irq(q->queue_lock); - q->rpm_status = RPM_RESUMING; - spin_unlock_irq(q->queue_lock); -} -EXPORT_SYMBOL(blk_pre_runtime_resume); - -/** - * blk_post_runtime_resume - Post runtime resume processing - * @q: the queue of the device - * @err: return value of the device's runtime_resume function - * - * Description: - * Update the queue's runtime status according to the return value of the - * device's runtime_resume function. If it is successfully resumed, process - * the requests that are queued into the device's queue when it is resuming - * and then mark last busy and initiate autosuspend for it. - * - * This function should be called near the end of the device's - * runtime_resume callback. - */ -void blk_post_runtime_resume(struct request_queue *q, int err) -{ - if (!q->dev) - return; - - spin_lock_irq(q->queue_lock); - if (!err) { - q->rpm_status = RPM_ACTIVE; - __blk_run_queue(q); - pm_runtime_mark_last_busy(q->dev); - pm_request_autosuspend(q->dev); - } else { - q->rpm_status = RPM_SUSPENDED; - } - spin_unlock_irq(q->queue_lock); -} -EXPORT_SYMBOL(blk_post_runtime_resume); - -/** - * blk_set_runtime_active - Force runtime status of the queue to be active - * @q: the queue of the device - * - * If the device is left runtime suspended during system suspend the resume - * hook typically resumes the device and corrects runtime status - * accordingly. However, that does not affect the queue runtime PM status - * which is still "suspended". This prevents processing requests from the - * queue. - * - * This function can be used in driver's resume hook to correct queue - * runtime PM status and re-enable peeking requests from the queue. It - * should be called before first request is added to the queue. - */ -void blk_set_runtime_active(struct request_queue *q) -{ - spin_lock_irq(q->queue_lock); - q->rpm_status = RPM_ACTIVE; - pm_runtime_mark_last_busy(q->dev); - pm_request_autosuspend(q->dev); - spin_unlock_irq(q->queue_lock); -} -EXPORT_SYMBOL(blk_set_runtime_active); -#endif - int __init blk_dev_init(void) { BUILD_BUG_ON(REQ_OP_LAST >= (1 << REQ_OP_BITS)); diff --git a/block/blk-flush.c b/block/blk-flush.c index ce41f666de3e..8b44b86779da 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -566,12 +566,12 @@ int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, EXPORT_SYMBOL(blkdev_issue_flush); struct blk_flush_queue *blk_alloc_flush_queue(struct request_queue *q, - int node, int cmd_size) + int node, int cmd_size, gfp_t flags) { struct blk_flush_queue *fq; int rq_sz = sizeof(struct request); - fq = kzalloc_node(sizeof(*fq), GFP_KERNEL, node); + fq = kzalloc_node(sizeof(*fq), flags, node); if (!fq) goto fail; @@ -579,7 +579,7 @@ struct blk_flush_queue *blk_alloc_flush_queue(struct request_queue *q, spin_lock_init(&fq->mq_flush_lock); rq_sz = round_up(rq_sz + cmd_size, cache_line_size()); - fq->flush_rq = kzalloc_node(rq_sz, GFP_KERNEL, node); + fq->flush_rq = kzalloc_node(rq_sz, flags, node); if (!fq->flush_rq) goto fail_rq; diff --git a/block/blk-integrity.c b/block/blk-integrity.c index 6121611e1316..d1ab089e0919 100644 --- a/block/blk-integrity.c +++ b/block/blk-integrity.c @@ -49,12 +49,8 @@ int blk_rq_count_integrity_sg(struct request_queue *q, struct bio *bio) bio_for_each_integrity_vec(iv, bio, iter) { if (prev) { - if (!BIOVEC_PHYS_MERGEABLE(&ivprv, &iv)) + if (!biovec_phys_mergeable(q, &ivprv, &iv)) goto new_segment; - - if (!BIOVEC_SEG_BOUNDARY(q, &ivprv, &iv)) - goto new_segment; - if (seg_size + iv.bv_len > queue_max_segment_size(q)) goto new_segment; @@ -95,12 +91,8 @@ int blk_rq_map_integrity_sg(struct request_queue *q, struct bio *bio, bio_for_each_integrity_vec(iv, bio, iter) { if (prev) { - if (!BIOVEC_PHYS_MERGEABLE(&ivprv, &iv)) + if (!biovec_phys_mergeable(q, &ivprv, &iv)) goto new_segment; - - if (!BIOVEC_SEG_BOUNDARY(q, &ivprv, &iv)) - goto new_segment; - if (sg->length + iv.bv_len > queue_max_segment_size(q)) goto new_segment; diff --git a/block/blk-iolatency.c b/block/blk-iolatency.c index 19923f8a029d..38c35c32aff2 100644 --- a/block/blk-iolatency.c +++ b/block/blk-iolatency.c @@ -115,9 +115,22 @@ struct child_latency_info { atomic_t scale_cookie; }; +struct percentile_stats { + u64 total; + u64 missed; +}; + +struct latency_stat { + union { + struct percentile_stats ps; + struct blk_rq_stat rqs; + }; +}; + struct iolatency_grp { struct blkg_policy_data pd; - struct blk_rq_stat __percpu *stats; + struct latency_stat __percpu *stats; + struct latency_stat cur_stat; struct blk_iolatency *blkiolat; struct rq_depth rq_depth; struct rq_wait rq_wait; @@ -132,6 +145,7 @@ struct iolatency_grp { /* Our current number of IO's for the last summation. */ u64 nr_samples; + bool ssd; struct child_latency_info child_lat; }; @@ -139,7 +153,7 @@ struct iolatency_grp { #define BLKIOLATENCY_MAX_WIN_SIZE NSEC_PER_SEC /* * These are the constants used to fake the fixed-point moving average - * calculation just like load average. The call to CALC_LOAD folds + * calculation just like load average. The call to calc_load() folds * (FIXED_1 (2048) - exp_factor) * new_sample into lat_avg. The sampling * window size is bucketed to try to approximately calculate average * latency such that 1/exp (decay rate) is [1 min, 2.5 min) when windows @@ -172,6 +186,82 @@ static inline struct blkcg_gq *lat_to_blkg(struct iolatency_grp *iolat) return pd_to_blkg(&iolat->pd); } +static inline void latency_stat_init(struct iolatency_grp *iolat, + struct latency_stat *stat) +{ + if (iolat->ssd) { + stat->ps.total = 0; + stat->ps.missed = 0; + } else + blk_rq_stat_init(&stat->rqs); +} + +static inline void latency_stat_sum(struct iolatency_grp *iolat, + struct latency_stat *sum, + struct latency_stat *stat) +{ + if (iolat->ssd) { + sum->ps.total += stat->ps.total; + sum->ps.missed += stat->ps.missed; + } else + blk_rq_stat_sum(&sum->rqs, &stat->rqs); +} + +static inline void latency_stat_record_time(struct iolatency_grp *iolat, + u64 req_time) +{ + struct latency_stat *stat = get_cpu_ptr(iolat->stats); + if (iolat->ssd) { + if (req_time >= iolat->min_lat_nsec) + stat->ps.missed++; + stat->ps.total++; + } else + blk_rq_stat_add(&stat->rqs, req_time); + put_cpu_ptr(stat); +} + +static inline bool latency_sum_ok(struct iolatency_grp *iolat, + struct latency_stat *stat) +{ + if (iolat->ssd) { + u64 thresh = div64_u64(stat->ps.total, 10); + thresh = max(thresh, 1ULL); + return stat->ps.missed < thresh; + } + return stat->rqs.mean <= iolat->min_lat_nsec; +} + +static inline u64 latency_stat_samples(struct iolatency_grp *iolat, + struct latency_stat *stat) +{ + if (iolat->ssd) + return stat->ps.total; + return stat->rqs.nr_samples; +} + +static inline void iolat_update_total_lat_avg(struct iolatency_grp *iolat, + struct latency_stat *stat) +{ + int exp_idx; + + if (iolat->ssd) + return; + + /* + * calc_load() takes in a number stored in fixed point representation. + * Because we are using this for IO time in ns, the values stored + * are significantly larger than the FIXED_1 denominator (2048). + * Therefore, rounding errors in the calculation are negligible and + * can be ignored. + */ + exp_idx = min_t(int, BLKIOLATENCY_NR_EXP_FACTORS - 1, + div64_u64(iolat->cur_win_nsec, + BLKIOLATENCY_EXP_BUCKET_SIZE)); + iolat->lat_avg = calc_load(iolat->lat_avg, + iolatency_exp_factors[exp_idx], + stat->rqs.mean); +} + static inline bool iolatency_may_queue(struct iolatency_grp *iolat, wait_queue_entry_t *wait, bool first_block) @@ -255,7 +345,7 @@ static void scale_cookie_change(struct blk_iolatency *blkiolat, struct child_latency_info *lat_info, bool up) { - unsigned long qd = blk_queue_depth(blkiolat->rqos.q); + unsigned long qd = blkiolat->rqos.q->nr_requests; unsigned long scale = scale_amount(qd, up); unsigned long old = atomic_read(&lat_info->scale_cookie); unsigned long max_scale = qd << 1; @@ -295,10 +385,9 @@ static void scale_cookie_change(struct blk_iolatency *blkiolat, */ static void scale_change(struct iolatency_grp *iolat, bool up) { - unsigned long qd = blk_queue_depth(iolat->blkiolat->rqos.q); + unsigned long qd = iolat->blkiolat->rqos.q->nr_requests; unsigned long scale = scale_amount(qd, up); unsigned long old = iolat->rq_depth.max_depth; - bool changed = false; if (old > qd) old = qd; @@ -308,15 +397,13 @@ static void scale_change(struct iolatency_grp *iolat, bool up) return; if (old < qd) { - changed = true; old += scale; old = min(old, qd); iolat->rq_depth.max_depth = old; wake_up_all(&iolat->rq_wait.wait); } - } else if (old > 1) { + } else { old >>= 1; - changed = true; iolat->rq_depth.max_depth = max(old, 1UL); } } @@ -369,7 +456,7 @@ static void check_scale_change(struct iolatency_grp *iolat) * scale down event. */ samples_thresh = lat_info->nr_samples * 5; - samples_thresh = div64_u64(samples_thresh, 100); + samples_thresh = max(1ULL, div64_u64(samples_thresh, 100)); if (iolat->nr_samples <= samples_thresh) return; } @@ -443,7 +530,6 @@ static void iolatency_record_time(struct iolatency_grp *iolat, struct bio_issue *issue, u64 now, bool issue_as_root) { - struct blk_rq_stat *rq_stat; u64 start = bio_issue_time(issue); u64 req_time; @@ -469,9 +555,7 @@ static void iolatency_record_time(struct iolatency_grp *iolat, return; } - rq_stat = get_cpu_ptr(iolat->stats); - blk_rq_stat_add(rq_stat, req_time); - put_cpu_ptr(rq_stat); + latency_stat_record_time(iolat, req_time); } #define BLKIOLATENCY_MIN_ADJUST_TIME (500 * NSEC_PER_MSEC) @@ -482,17 +566,17 @@ static void iolatency_check_latencies(struct iolatency_grp *iolat, u64 now) struct blkcg_gq *blkg = lat_to_blkg(iolat); struct iolatency_grp *parent; struct child_latency_info *lat_info; - struct blk_rq_stat stat; + struct latency_stat stat; unsigned long flags; - int cpu, exp_idx; + int cpu; - blk_rq_stat_init(&stat); + latency_stat_init(iolat, &stat); preempt_disable(); for_each_online_cpu(cpu) { - struct blk_rq_stat *s; + struct latency_stat *s; s = per_cpu_ptr(iolat->stats, cpu); - blk_rq_stat_sum(&stat, s); - blk_rq_stat_init(s); + latency_stat_sum(iolat, &stat, s); + latency_stat_init(iolat, s); } preempt_enable(); @@ -502,41 +586,36 @@ static void iolatency_check_latencies(struct iolatency_grp *iolat, u64 now) lat_info = &parent->child_lat; - /* - * CALC_LOAD takes in a number stored in fixed point representation. - * Because we are using this for IO time in ns, the values stored - * are significantly larger than the FIXED_1 denominator (2048). - * Therefore, rounding errors in the calculation are negligible and - * can be ignored. - */ - exp_idx = min_t(int, BLKIOLATENCY_NR_EXP_FACTORS - 1, - div64_u64(iolat->cur_win_nsec, - BLKIOLATENCY_EXP_BUCKET_SIZE)); - CALC_LOAD(iolat->lat_avg, iolatency_exp_factors[exp_idx], stat.mean); + iolat_update_total_lat_avg(iolat, &stat); /* Everything is ok and we don't need to adjust the scale. */ - if (stat.mean <= iolat->min_lat_nsec && + if (latency_sum_ok(iolat, &stat) && atomic_read(&lat_info->scale_cookie) == DEFAULT_SCALE_COOKIE) return; /* Somebody beat us to the punch, just bail. */ spin_lock_irqsave(&lat_info->lock, flags); + + latency_stat_sum(iolat, &iolat->cur_stat, &stat); lat_info->nr_samples -= iolat->nr_samples; - lat_info->nr_samples += stat.nr_samples; - iolat->nr_samples = stat.nr_samples; + lat_info->nr_samples += latency_stat_samples(iolat, &iolat->cur_stat); + iolat->nr_samples = latency_stat_samples(iolat, &iolat->cur_stat); if ((lat_info->last_scale_event >= now || - now - lat_info->last_scale_event < BLKIOLATENCY_MIN_ADJUST_TIME) && - lat_info->scale_lat <= iolat->min_lat_nsec) + now - lat_info->last_scale_event < BLKIOLATENCY_MIN_ADJUST_TIME)) goto out; - if (stat.mean <= iolat->min_lat_nsec && - stat.nr_samples >= BLKIOLATENCY_MIN_GOOD_SAMPLES) { + if (latency_sum_ok(iolat, &iolat->cur_stat) && + latency_sum_ok(iolat, &stat)) { + if (latency_stat_samples(iolat, &iolat->cur_stat) < + BLKIOLATENCY_MIN_GOOD_SAMPLES) + goto out; if (lat_info->scale_grp == iolat) { lat_info->last_scale_event = now; scale_cookie_change(iolat->blkiolat, lat_info, true); } - } else if (stat.mean > iolat->min_lat_nsec) { + } else if (lat_info->scale_lat == 0 || + lat_info->scale_lat >= iolat->min_lat_nsec) { lat_info->last_scale_event = now; if (!lat_info->scale_grp || lat_info->scale_lat > iolat->min_lat_nsec) { @@ -545,6 +624,7 @@ static void iolatency_check_latencies(struct iolatency_grp *iolat, u64 now) } scale_cookie_change(iolat->blkiolat, lat_info, false); } + latency_stat_init(iolat, &iolat->cur_stat); out: spin_unlock_irqrestore(&lat_info->lock, flags); } @@ -761,7 +841,6 @@ static ssize_t iolatency_set_limit(struct kernfs_open_file *of, char *buf, { struct blkcg *blkcg = css_to_blkcg(of_css(of)); struct blkcg_gq *blkg; - struct blk_iolatency *blkiolat; struct blkg_conf_ctx ctx; struct iolatency_grp *iolat; char *p, *tok; @@ -774,7 +853,6 @@ static ssize_t iolatency_set_limit(struct kernfs_open_file *of, char *buf, return ret; iolat = blkg_to_lat(ctx.blkg); - blkiolat = iolat->blkiolat; p = ctx.body; ret = -EINVAL; @@ -835,13 +913,43 @@ static int iolatency_print_limit(struct seq_file *sf, void *v) return 0; } +static size_t iolatency_ssd_stat(struct iolatency_grp *iolat, char *buf, + size_t size) +{ + struct latency_stat stat; + int cpu; + + latency_stat_init(iolat, &stat); + preempt_disable(); + for_each_online_cpu(cpu) { + struct latency_stat *s; + s = per_cpu_ptr(iolat->stats, cpu); + latency_stat_sum(iolat, &stat, s); + } + preempt_enable(); + + if (iolat->rq_depth.max_depth == UINT_MAX) + return scnprintf(buf, size, " missed=%llu total=%llu depth=max", + (unsigned long long)stat.ps.missed, + (unsigned long long)stat.ps.total); + return scnprintf(buf, size, " missed=%llu total=%llu depth=%u", + (unsigned long long)stat.ps.missed, + (unsigned long long)stat.ps.total, + iolat->rq_depth.max_depth); +} + static size_t iolatency_pd_stat(struct blkg_policy_data *pd, char *buf, size_t size) { struct iolatency_grp *iolat = pd_to_lat(pd); - unsigned long long avg_lat = div64_u64(iolat->lat_avg, NSEC_PER_USEC); - unsigned long long cur_win = div64_u64(iolat->cur_win_nsec, NSEC_PER_MSEC); + unsigned long long avg_lat; + unsigned long long cur_win; + + if (iolat->ssd) + return iolatency_ssd_stat(iolat, buf, size); + avg_lat = div64_u64(iolat->lat_avg, NSEC_PER_USEC); + cur_win = div64_u64(iolat->cur_win_nsec, NSEC_PER_MSEC); if (iolat->rq_depth.max_depth == UINT_MAX) return scnprintf(buf, size, " depth=max avg_lat=%llu win=%llu", avg_lat, cur_win); @@ -858,8 +966,8 @@ static struct blkg_policy_data *iolatency_pd_alloc(gfp_t gfp, int node) iolat = kzalloc_node(sizeof(*iolat), gfp, node); if (!iolat) return NULL; - iolat->stats = __alloc_percpu_gfp(sizeof(struct blk_rq_stat), - __alignof__(struct blk_rq_stat), gfp); + iolat->stats = __alloc_percpu_gfp(sizeof(struct latency_stat), + __alignof__(struct latency_stat), gfp); if (!iolat->stats) { kfree(iolat); return NULL; @@ -876,15 +984,21 @@ static void iolatency_pd_init(struct blkg_policy_data *pd) u64 now = ktime_to_ns(ktime_get()); int cpu; + if (blk_queue_nonrot(blkg->q)) + iolat->ssd = true; + else + iolat->ssd = false; + for_each_possible_cpu(cpu) { - struct blk_rq_stat *stat; + struct latency_stat *stat; stat = per_cpu_ptr(iolat->stats, cpu); - blk_rq_stat_init(stat); + latency_stat_init(iolat, stat); } + latency_stat_init(iolat, &iolat->cur_stat); rq_wait_init(&iolat->rq_wait); spin_lock_init(&iolat->child_lat.lock); - iolat->rq_depth.queue_depth = blk_queue_depth(blkg->q); + iolat->rq_depth.queue_depth = blkg->q->nr_requests; iolat->rq_depth.max_depth = UINT_MAX; iolat->rq_depth.default_depth = iolat->rq_depth.queue_depth; iolat->blkiolat = blkiolat; diff --git a/block/blk-lib.c b/block/blk-lib.c index d1b9dd03da25..76f867ea9a9b 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -10,8 +10,7 @@ #include "blk.h" -static struct bio *next_bio(struct bio *bio, unsigned int nr_pages, - gfp_t gfp) +struct bio *blk_next_bio(struct bio *bio, unsigned int nr_pages, gfp_t gfp) { struct bio *new = bio_alloc(gfp, nr_pages); @@ -29,9 +28,7 @@ int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, { struct request_queue *q = bdev_get_queue(bdev); struct bio *bio = *biop; - unsigned int granularity; unsigned int op; - int alignment; sector_t bs_mask; if (!q) @@ -54,40 +51,18 @@ int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, if ((sector | nr_sects) & bs_mask) return -EINVAL; - /* Zero-sector (unknown) and one-sector granularities are the same. */ - granularity = max(q->limits.discard_granularity >> 9, 1U); - alignment = (bdev_discard_alignment(bdev) >> 9) % granularity; - while (nr_sects) { - unsigned int req_sects; - sector_t end_sect, tmp; + unsigned int req_sects = nr_sects; + sector_t end_sect; - /* - * Issue in chunks of the user defined max discard setting, - * ensuring that bi_size doesn't overflow - */ - req_sects = min_t(sector_t, nr_sects, - q->limits.max_discard_sectors); if (!req_sects) goto fail; if (req_sects > UINT_MAX >> 9) req_sects = UINT_MAX >> 9; - /* - * If splitting a request, and the next starting sector would be - * misaligned, stop the discard at the previous aligned sector. - */ end_sect = sector + req_sects; - tmp = end_sect; - if (req_sects < nr_sects && - sector_div(tmp, granularity) != alignment) { - end_sect = end_sect - alignment; - sector_div(end_sect, granularity); - end_sect = end_sect * granularity + alignment; - req_sects = end_sect - sector; - } - bio = next_bio(bio, 0, gfp_mask); + bio = blk_next_bio(bio, 0, gfp_mask); bio->bi_iter.bi_sector = sector; bio_set_dev(bio, bdev); bio_set_op_attrs(bio, op, 0); @@ -189,7 +164,7 @@ static int __blkdev_issue_write_same(struct block_device *bdev, sector_t sector, max_write_same_sectors = UINT_MAX >> 9; while (nr_sects) { - bio = next_bio(bio, 1, gfp_mask); + bio = blk_next_bio(bio, 1, gfp_mask); bio->bi_iter.bi_sector = sector; bio_set_dev(bio, bdev); bio->bi_vcnt = 1; @@ -265,7 +240,7 @@ static int __blkdev_issue_write_zeroes(struct block_device *bdev, return -EOPNOTSUPP; while (nr_sects) { - bio = next_bio(bio, 0, gfp_mask); + bio = blk_next_bio(bio, 0, gfp_mask); bio->bi_iter.bi_sector = sector; bio_set_dev(bio, bdev); bio->bi_opf = REQ_OP_WRITE_ZEROES; @@ -316,8 +291,8 @@ static int __blkdev_issue_zero_pages(struct block_device *bdev, return -EPERM; while (nr_sects != 0) { - bio = next_bio(bio, __blkdev_sectors_to_bio_pages(nr_sects), - gfp_mask); + bio = blk_next_bio(bio, __blkdev_sectors_to_bio_pages(nr_sects), + gfp_mask); bio->bi_iter.bi_sector = sector; bio_set_dev(bio, bdev); bio_set_op_attrs(bio, REQ_OP_WRITE, 0); diff --git a/block/blk-merge.c b/block/blk-merge.c index aaec38cc37b8..6b5ad275ed56 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -12,6 +12,69 @@ #include "blk.h" +/* + * Check if the two bvecs from two bios can be merged to one segment. If yes, + * no need to check gap between the two bios since the 1st bio and the 1st bvec + * in the 2nd bio can be handled in one segment. + */ +static inline bool bios_segs_mergeable(struct request_queue *q, + struct bio *prev, struct bio_vec *prev_last_bv, + struct bio_vec *next_first_bv) +{ + if (!biovec_phys_mergeable(q, prev_last_bv, next_first_bv)) + return false; + if (prev->bi_seg_back_size + next_first_bv->bv_len > + queue_max_segment_size(q)) + return false; + return true; +} + +static inline bool bio_will_gap(struct request_queue *q, + struct request *prev_rq, struct bio *prev, struct bio *next) +{ + struct bio_vec pb, nb; + + if (!bio_has_data(prev) || !queue_virt_boundary(q)) + return false; + + /* + * Don't merge if the 1st bio starts with non-zero offset, otherwise it + * is quite difficult to respect the sg gap limit. We work hard to + * merge a huge number of small single bios in case of mkfs. + */ + if (prev_rq) + bio_get_first_bvec(prev_rq->bio, &pb); + else + bio_get_first_bvec(prev, &pb); + if (pb.bv_offset) + return true; + + /* + * We don't need to worry about the situation that the merged segment + * ends in unaligned virt boundary: + * + * - if 'pb' ends aligned, the merged segment ends aligned + * - if 'pb' ends unaligned, the next bio must include + * one single bvec of 'nb', otherwise the 'nb' can't + * merge with 'pb' + */ + bio_get_last_bvec(prev, &pb); + bio_get_first_bvec(next, &nb); + if (bios_segs_mergeable(q, prev, &pb, &nb)) + return false; + return __bvec_gap_to_prev(q, &pb, nb.bv_offset); +} + +static inline bool req_gap_back_merge(struct request *req, struct bio *bio) +{ + return bio_will_gap(req->q, req, req->biotail, bio); +} + +static inline bool req_gap_front_merge(struct request *req, struct bio *bio) +{ + return bio_will_gap(req->q, NULL, bio, req->bio); +} + static struct bio *blk_bio_discard_split(struct request_queue *q, struct bio *bio, struct bio_set *bs, @@ -134,9 +197,7 @@ static struct bio *blk_bio_segment_split(struct request_queue *q, if (bvprvp && blk_queue_cluster(q)) { if (seg_size + bv.bv_len > queue_max_segment_size(q)) goto new_segment; - if (!BIOVEC_PHYS_MERGEABLE(bvprvp, &bv)) - goto new_segment; - if (!BIOVEC_SEG_BOUNDARY(q, bvprvp, &bv)) + if (!biovec_phys_mergeable(q, bvprvp, &bv)) goto new_segment; seg_size += bv.bv_len; @@ -267,9 +328,7 @@ static unsigned int __blk_recalc_rq_segments(struct request_queue *q, if (seg_size + bv.bv_len > queue_max_segment_size(q)) goto new_segment; - if (!BIOVEC_PHYS_MERGEABLE(&bvprv, &bv)) - goto new_segment; - if (!BIOVEC_SEG_BOUNDARY(q, &bvprv, &bv)) + if (!biovec_phys_mergeable(q, &bvprv, &bv)) goto new_segment; seg_size += bv.bv_len; @@ -349,17 +408,7 @@ static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio, bio_get_last_bvec(bio, &end_bv); bio_get_first_bvec(nxt, &nxt_bv); - if (!BIOVEC_PHYS_MERGEABLE(&end_bv, &nxt_bv)) - return 0; - - /* - * bio and nxt are contiguous in memory; check if the queue allows - * these two to be merged into one - */ - if (BIOVEC_SEG_BOUNDARY(q, &end_bv, &nxt_bv)) - return 1; - - return 0; + return biovec_phys_mergeable(q, &end_bv, &nxt_bv); } static inline void @@ -373,10 +422,7 @@ __blk_segment_map_sg(struct request_queue *q, struct bio_vec *bvec, if (*sg && *cluster) { if ((*sg)->length + nbytes > queue_max_segment_size(q)) goto new_segment; - - if (!BIOVEC_PHYS_MERGEABLE(bvprv, bvec)) - goto new_segment; - if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bvec)) + if (!biovec_phys_mergeable(q, bvprv, bvec)) goto new_segment; (*sg)->length += nbytes; @@ -668,6 +714,31 @@ static void blk_account_io_merge(struct request *req) part_stat_unlock(); } } +/* + * Two cases of handling DISCARD merge: + * If max_discard_segments > 1, the driver takes every bio + * as a range and send them to controller together. The ranges + * needn't to be contiguous. + * Otherwise, the bios/requests will be handled as same as + * others which should be contiguous. + */ +static inline bool blk_discard_mergable(struct request *req) +{ + if (req_op(req) == REQ_OP_DISCARD && + queue_max_discard_segments(req->q) > 1) + return true; + return false; +} + +enum elv_merge blk_try_req_merge(struct request *req, struct request *next) +{ + if (blk_discard_mergable(req)) + return ELEVATOR_DISCARD_MERGE; + else if (blk_rq_pos(req) + blk_rq_sectors(req) == blk_rq_pos(next)) + return ELEVATOR_BACK_MERGE; + + return ELEVATOR_NO_MERGE; +} /* * For non-mq, this has to be called with the request spinlock acquired. @@ -685,12 +756,6 @@ static struct request *attempt_merge(struct request_queue *q, if (req_op(req) != req_op(next)) return NULL; - /* - * not contiguous - */ - if (blk_rq_pos(req) + blk_rq_sectors(req) != blk_rq_pos(next)) - return NULL; - if (rq_data_dir(req) != rq_data_dir(next) || req->rq_disk != next->rq_disk || req_no_special_merge(next)) @@ -714,11 +779,19 @@ static struct request *attempt_merge(struct request_queue *q, * counts here. Handle DISCARDs separately, as they * have separate settings. */ - if (req_op(req) == REQ_OP_DISCARD) { + + switch (blk_try_req_merge(req, next)) { + case ELEVATOR_DISCARD_MERGE: if (!req_attempt_discard_merge(q, req, next)) return NULL; - } else if (!ll_merge_requests_fn(q, req, next)) + break; + case ELEVATOR_BACK_MERGE: + if (!ll_merge_requests_fn(q, req, next)) + return NULL; + break; + default: return NULL; + } /* * If failfast settings disagree or any of the two is already @@ -842,8 +915,7 @@ bool blk_rq_merge_ok(struct request *rq, struct bio *bio) enum elv_merge blk_try_merge(struct request *rq, struct bio *bio) { - if (req_op(rq) == REQ_OP_DISCARD && - queue_max_discard_segments(rq->q) > 1) + if (blk_discard_mergable(rq)) return ELEVATOR_DISCARD_MERGE; else if (blk_rq_pos(rq) + blk_rq_sectors(rq) == bio->bi_iter.bi_sector) return ELEVATOR_BACK_MERGE; diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c index cb1e6cf7ac48..10b284a1f18d 100644 --- a/block/blk-mq-debugfs.c +++ b/block/blk-mq-debugfs.c @@ -102,6 +102,14 @@ static int blk_flags_show(struct seq_file *m, const unsigned long flags, return 0; } +static int queue_pm_only_show(void *data, struct seq_file *m) +{ + struct request_queue *q = data; + + seq_printf(m, "%d\n", atomic_read(&q->pm_only)); + return 0; +} + #define QUEUE_FLAG_NAME(name) [QUEUE_FLAG_##name] = #name static const char *const blk_queue_flag_name[] = { QUEUE_FLAG_NAME(QUEUED), @@ -132,7 +140,6 @@ static const char *const blk_queue_flag_name[] = { QUEUE_FLAG_NAME(REGISTERED), QUEUE_FLAG_NAME(SCSI_PASSTHROUGH), QUEUE_FLAG_NAME(QUIESCED), - QUEUE_FLAG_NAME(PREEMPT_ONLY), }; #undef QUEUE_FLAG_NAME @@ -209,6 +216,7 @@ static ssize_t queue_write_hint_store(void *data, const char __user *buf, static const struct blk_mq_debugfs_attr blk_mq_debugfs_queue_attrs[] = { { "poll_stat", 0400, queue_poll_stat_show }, { "requeue_list", 0400, .seq_ops = &queue_requeue_list_seq_ops }, + { "pm_only", 0600, queue_pm_only_show, NULL }, { "state", 0600, queue_state_show, queue_state_write }, { "write_hints", 0600, queue_write_hint_show, queue_write_hint_store }, { "zone_wlock", 0400, queue_zone_wlock_show, NULL }, @@ -275,7 +283,6 @@ static const char *const op_name[] = { REQ_OP_NAME(WRITE), REQ_OP_NAME(FLUSH), REQ_OP_NAME(DISCARD), - REQ_OP_NAME(ZONE_REPORT), REQ_OP_NAME(SECURE_ERASE), REQ_OP_NAME(ZONE_RESET), REQ_OP_NAME(WRITE_SAME), @@ -423,8 +430,7 @@ static void hctx_show_busy_rq(struct request *rq, void *data, bool reserved) { const struct show_busy_params *params = data; - if (blk_mq_map_queue(rq->q, rq->mq_ctx->cpu) == params->hctx && - blk_mq_rq_state(rq) != MQ_RQ_IDLE) + if (blk_mq_map_queue(rq->q, rq->mq_ctx->cpu) == params->hctx) __blk_mq_debugfs_rq_show(params->m, list_entry_rq(&rq->queuelist)); } diff --git a/block/blk-mq-sched.h b/block/blk-mq-sched.h index 4e028ee42430..8a9544203173 100644 --- a/block/blk-mq-sched.h +++ b/block/blk-mq-sched.h @@ -49,12 +49,12 @@ blk_mq_sched_allow_merge(struct request_queue *q, struct request *rq, return true; } -static inline void blk_mq_sched_completed_request(struct request *rq) +static inline void blk_mq_sched_completed_request(struct request *rq, u64 now) { struct elevator_queue *e = rq->q->elevator; if (e && e->type->ops.mq.completed_request) - e->type->ops.mq.completed_request(rq); + e->type->ops.mq.completed_request(rq, now); } static inline void blk_mq_sched_started_request(struct request *rq) diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 41317c50a446..cfda95b85d34 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -232,13 +232,26 @@ static bool bt_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data) /* * We can hit rq == NULL here, because the tagging functions - * test and set the bit before assining ->rqs[]. + * test and set the bit before assigning ->rqs[]. */ if (rq && rq->q == hctx->queue) iter_data->fn(hctx, rq, iter_data->data, reserved); return true; } +/** + * bt_for_each - iterate over the requests associated with a hardware queue + * @hctx: Hardware queue to examine. + * @bt: sbitmap to examine. This is either the breserved_tags member + * or the bitmap_tags member of struct blk_mq_tags. + * @fn: Pointer to the function that will be called for each request + * associated with @hctx that has been assigned a driver tag. + * @fn will be called as follows: @fn(@hctx, rq, @data, @reserved) + * where rq is a pointer to a request. + * @data: Will be passed as third argument to @fn. + * @reserved: Indicates whether @bt is the breserved_tags member or the + * bitmap_tags member of struct blk_mq_tags. + */ static void bt_for_each(struct blk_mq_hw_ctx *hctx, struct sbitmap_queue *bt, busy_iter_fn *fn, void *data, bool reserved) { @@ -280,6 +293,18 @@ static bool bt_tags_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data) return true; } +/** + * bt_tags_for_each - iterate over the requests in a tag map + * @tags: Tag map to iterate over. + * @bt: sbitmap to examine. This is either the breserved_tags member + * or the bitmap_tags member of struct blk_mq_tags. + * @fn: Pointer to the function that will be called for each started + * request. @fn will be called as follows: @fn(rq, @data, + * @reserved) where rq is a pointer to a request. + * @data: Will be passed as second argument to @fn. + * @reserved: Indicates whether @bt is the breserved_tags member or the + * bitmap_tags member of struct blk_mq_tags. + */ static void bt_tags_for_each(struct blk_mq_tags *tags, struct sbitmap_queue *bt, busy_tag_iter_fn *fn, void *data, bool reserved) { @@ -294,6 +319,15 @@ static void bt_tags_for_each(struct blk_mq_tags *tags, struct sbitmap_queue *bt, sbitmap_for_each_set(&bt->sb, bt_tags_iter, &iter_data); } +/** + * blk_mq_all_tag_busy_iter - iterate over all started requests in a tag map + * @tags: Tag map to iterate over. + * @fn: Pointer to the function that will be called for each started + * request. @fn will be called as follows: @fn(rq, @priv, + * reserved) where rq is a pointer to a request. 'reserved' + * indicates whether or not @rq is a reserved request. + * @priv: Will be passed as second argument to @fn. + */ static void blk_mq_all_tag_busy_iter(struct blk_mq_tags *tags, busy_tag_iter_fn *fn, void *priv) { @@ -302,6 +336,15 @@ static void blk_mq_all_tag_busy_iter(struct blk_mq_tags *tags, bt_tags_for_each(tags, &tags->bitmap_tags, fn, priv, false); } +/** + * blk_mq_tagset_busy_iter - iterate over all started requests in a tag set + * @tagset: Tag set to iterate over. + * @fn: Pointer to the function that will be called for each started + * request. @fn will be called as follows: @fn(rq, @priv, + * reserved) where rq is a pointer to a request. 'reserved' + * indicates whether or not @rq is a reserved request. + * @priv: Will be passed as second argument to @fn. + */ void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset, busy_tag_iter_fn *fn, void *priv) { @@ -314,6 +357,20 @@ void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset, } EXPORT_SYMBOL(blk_mq_tagset_busy_iter); +/** + * blk_mq_queue_tag_busy_iter - iterate over all requests with a driver tag + * @q: Request queue to examine. + * @fn: Pointer to the function that will be called for each request + * on @q. @fn will be called as follows: @fn(hctx, rq, @priv, + * reserved) where rq is a pointer to a request and hctx points + * to the hardware queue associated with the request. 'reserved' + * indicates whether or not @rq is a reserved request. + * @priv: Will be passed as third argument to @fn. + * + * Note: if @q->tag_set is shared with other request queues then @fn will be + * called for all requests on all queues that share that tag set and not only + * for requests associated with @q. + */ void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn, void *priv) { @@ -321,9 +378,11 @@ void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn, int i; /* - * __blk_mq_update_nr_hw_queues will update the nr_hw_queues and - * queue_hw_ctx after freeze the queue, so we use q_usage_counter - * to avoid race with it. + * __blk_mq_update_nr_hw_queues() updates nr_hw_queues and queue_hw_ctx + * while the queue is frozen. So we can use q_usage_counter to avoid + * racing with it. __blk_mq_update_nr_hw_queues() uses + * synchronize_rcu() to ensure this function left the critical section + * below. */ if (!percpu_ref_tryget(&q->q_usage_counter)) return; @@ -332,7 +391,7 @@ void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn, struct blk_mq_tags *tags = hctx->tags; /* - * If not software queues are currently mapped to this + * If no software queues are currently mapped to this * hardware queue, there's nothing to check */ if (!blk_mq_hw_queue_mapped(hctx)) diff --git a/block/blk-mq.c b/block/blk-mq.c index e3c39ea8e17b..3f91c6e5b17a 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -33,6 +33,7 @@ #include "blk-mq.h" #include "blk-mq-debugfs.h" #include "blk-mq-tag.h" +#include "blk-pm.h" #include "blk-stat.h" #include "blk-mq-sched.h" #include "blk-rq-qos.h" @@ -198,7 +199,7 @@ void blk_mq_unfreeze_queue(struct request_queue *q) freeze_depth = atomic_dec_return(&q->mq_freeze_depth); WARN_ON_ONCE(freeze_depth < 0); if (!freeze_depth) { - percpu_ref_reinit(&q->q_usage_counter); + percpu_ref_resurrect(&q->q_usage_counter); wake_up_all(&q->mq_freeze_wq); } } @@ -475,6 +476,7 @@ static void __blk_mq_free_request(struct request *rq) struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, ctx->cpu); const int sched_tag = rq->internal_tag; + blk_pm_mark_last_busy(rq); if (rq->tag != -1) blk_mq_put_tag(hctx, hctx->tags, ctx, rq->tag); if (sched_tag != -1) @@ -526,6 +528,9 @@ inline void __blk_mq_end_request(struct request *rq, blk_status_t error) blk_stat_add(rq, now); } + if (rq->internal_tag != -1) + blk_mq_sched_completed_request(rq, now); + blk_account_io_done(rq, now); if (rq->end_io) { @@ -562,8 +567,20 @@ static void __blk_mq_complete_request(struct request *rq) if (!blk_mq_mark_complete(rq)) return; - if (rq->internal_tag != -1) - blk_mq_sched_completed_request(rq); + + /* + * Most of single queue controllers, there is only one irq vector + * for handling IO completion, and the only irq's affinity is set + * as all possible CPUs. On most of ARCHs, this affinity means the + * irq is handled on one specific CPU. + * + * So complete IO reqeust in softirq context in case of single queue + * for not degrading IO performance by irqsoff latency. + */ + if (rq->q->nr_hw_queues == 1) { + __blk_complete_request(rq); + return; + } if (!test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) { rq->q->softirq_done_fn(rq); @@ -1833,8 +1850,6 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) rq_qos_throttle(q, bio, NULL); - trace_block_getrq(q, bio, bio->bi_opf); - rq = blk_mq_get_request(q, bio, bio->bi_opf, &data); if (unlikely(!rq)) { rq_qos_cleanup(q, bio); @@ -1843,6 +1858,8 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) return BLK_QC_T_NONE; } + trace_block_getrq(q, bio, bio->bi_opf); + rq_qos_track(q, rq, bio); cookie = request_to_qc_t(data.hctx, rq); @@ -2137,8 +2154,6 @@ static void blk_mq_exit_hctx(struct request_queue *q, struct blk_mq_tag_set *set, struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx) { - blk_mq_debugfs_unregister_hctx(hctx); - if (blk_mq_hw_queue_mapped(hctx)) blk_mq_tag_idle(hctx); @@ -2165,6 +2180,7 @@ static void blk_mq_exit_hw_queues(struct request_queue *q, queue_for_each_hw_ctx(q, hctx, i) { if (i == nr_queue) break; + blk_mq_debugfs_unregister_hctx(hctx); blk_mq_exit_hctx(q, set, hctx, i); } } @@ -2194,12 +2210,12 @@ static int blk_mq_init_hctx(struct request_queue *q, * runtime */ hctx->ctxs = kmalloc_array_node(nr_cpu_ids, sizeof(void *), - GFP_KERNEL, node); + GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY, node); if (!hctx->ctxs) goto unregister_cpu_notifier; - if (sbitmap_init_node(&hctx->ctx_map, nr_cpu_ids, ilog2(8), GFP_KERNEL, - node)) + if (sbitmap_init_node(&hctx->ctx_map, nr_cpu_ids, ilog2(8), + GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY, node)) goto free_ctxs; hctx->nr_ctx = 0; @@ -2212,7 +2228,8 @@ static int blk_mq_init_hctx(struct request_queue *q, set->ops->init_hctx(hctx, set->driver_data, hctx_idx)) goto free_bitmap; - hctx->fq = blk_alloc_flush_queue(q, hctx->numa_node, set->cmd_size); + hctx->fq = blk_alloc_flush_queue(q, hctx->numa_node, set->cmd_size, + GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY); if (!hctx->fq) goto exit_hctx; @@ -2222,8 +2239,6 @@ static int blk_mq_init_hctx(struct request_queue *q, if (hctx->flags & BLK_MQ_F_BLOCKING) init_srcu_struct(hctx->srcu); - blk_mq_debugfs_register_hctx(q, hctx); - return 0; free_fq: @@ -2492,6 +2507,39 @@ struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set) } EXPORT_SYMBOL(blk_mq_init_queue); +/* + * Helper for setting up a queue with mq ops, given queue depth, and + * the passed in mq ops flags. + */ +struct request_queue *blk_mq_init_sq_queue(struct blk_mq_tag_set *set, + const struct blk_mq_ops *ops, + unsigned int queue_depth, + unsigned int set_flags) +{ + struct request_queue *q; + int ret; + + memset(set, 0, sizeof(*set)); + set->ops = ops; + set->nr_hw_queues = 1; + set->queue_depth = queue_depth; + set->numa_node = NUMA_NO_NODE; + set->flags = set_flags; + + ret = blk_mq_alloc_tag_set(set); + if (ret) + return ERR_PTR(ret); + + q = blk_mq_init_queue(set); + if (IS_ERR(q)) { + blk_mq_free_tag_set(set); + return q; + } + + return q; +} +EXPORT_SYMBOL(blk_mq_init_sq_queue); + static int blk_mq_hw_ctx_size(struct blk_mq_tag_set *tag_set) { int hw_ctx_size = sizeof(struct blk_mq_hw_ctx); @@ -2506,48 +2554,90 @@ static int blk_mq_hw_ctx_size(struct blk_mq_tag_set *tag_set) return hw_ctx_size; } +static struct blk_mq_hw_ctx *blk_mq_alloc_and_init_hctx( + struct blk_mq_tag_set *set, struct request_queue *q, + int hctx_idx, int node) +{ + struct blk_mq_hw_ctx *hctx; + + hctx = kzalloc_node(blk_mq_hw_ctx_size(set), + GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY, + node); + if (!hctx) + return NULL; + + if (!zalloc_cpumask_var_node(&hctx->cpumask, + GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY, + node)) { + kfree(hctx); + return NULL; + } + + atomic_set(&hctx->nr_active, 0); + hctx->numa_node = node; + hctx->queue_num = hctx_idx; + + if (blk_mq_init_hctx(q, set, hctx, hctx_idx)) { + free_cpumask_var(hctx->cpumask); + kfree(hctx); + return NULL; + } + blk_mq_hctx_kobj_init(hctx); + + return hctx; +} + static void blk_mq_realloc_hw_ctxs(struct blk_mq_tag_set *set, struct request_queue *q) { - int i, j; + int i, j, end; struct blk_mq_hw_ctx **hctxs = q->queue_hw_ctx; - blk_mq_sysfs_unregister(q); - /* protect against switching io scheduler */ mutex_lock(&q->sysfs_lock); for (i = 0; i < set->nr_hw_queues; i++) { int node; - - if (hctxs[i]) - continue; + struct blk_mq_hw_ctx *hctx; node = blk_mq_hw_queue_to_node(q->mq_map, i); - hctxs[i] = kzalloc_node(blk_mq_hw_ctx_size(set), - GFP_KERNEL, node); - if (!hctxs[i]) - break; - - if (!zalloc_cpumask_var_node(&hctxs[i]->cpumask, GFP_KERNEL, - 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 the hw queue has been mapped to another numa node, + * we need to realloc the hctx. If allocation fails, fallback + * to use the previous one. + */ + if (hctxs[i] && (hctxs[i]->numa_node == node)) + continue; - if (blk_mq_init_hctx(q, set, hctxs[i], i)) { - free_cpumask_var(hctxs[i]->cpumask); - kfree(hctxs[i]); - hctxs[i] = NULL; - break; + hctx = blk_mq_alloc_and_init_hctx(set, q, i, node); + if (hctx) { + if (hctxs[i]) { + blk_mq_exit_hctx(q, set, hctxs[i], i); + kobject_put(&hctxs[i]->kobj); + } + hctxs[i] = hctx; + } else { + if (hctxs[i]) + pr_warn("Allocate new hctx on node %d fails,\ + fallback to previous one on node %d\n", + node, hctxs[i]->numa_node); + else + break; } - blk_mq_hctx_kobj_init(hctxs[i]); } - for (j = i; j < q->nr_hw_queues; j++) { + /* + * Increasing nr_hw_queues fails. Free the newly allocated + * hctxs and keep the previous q->nr_hw_queues. + */ + if (i != set->nr_hw_queues) { + j = q->nr_hw_queues; + end = i; + } else { + j = i; + end = q->nr_hw_queues; + q->nr_hw_queues = set->nr_hw_queues; + } + + for (; j < end; j++) { struct blk_mq_hw_ctx *hctx = hctxs[j]; if (hctx) { @@ -2559,9 +2649,7 @@ static void blk_mq_realloc_hw_ctxs(struct blk_mq_tag_set *set, } } - q->nr_hw_queues = i; mutex_unlock(&q->sysfs_lock); - blk_mq_sysfs_register(q); } struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, @@ -2659,25 +2747,6 @@ void blk_mq_free_queue(struct request_queue *q) blk_mq_exit_hw_queues(q, set, set->nr_hw_queues); } -/* Basically redo blk_mq_init_queue with queue frozen */ -static void blk_mq_queue_reinit(struct request_queue *q) -{ - WARN_ON_ONCE(!atomic_read(&q->mq_freeze_depth)); - - blk_mq_debugfs_unregister_hctxs(q); - blk_mq_sysfs_unregister(q); - - /* - * redo blk_mq_init_cpu_queues and blk_mq_init_hw_queues. FIXME: maybe - * we should change hctx numa_node according to the new topology (this - * involves freeing and re-allocating memory, worth doing?) - */ - blk_mq_map_swqueue(q); - - blk_mq_sysfs_register(q); - blk_mq_debugfs_register_hctxs(q); -} - static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) { int i; @@ -2964,6 +3033,7 @@ static void __blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, { struct request_queue *q; LIST_HEAD(head); + int prev_nr_hw_queues; lockdep_assert_held(&set->tag_list_lock); @@ -2987,11 +3057,30 @@ static void __blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, if (!blk_mq_elv_switch_none(&head, q)) goto switch_back; + list_for_each_entry(q, &set->tag_list, tag_set_list) { + blk_mq_debugfs_unregister_hctxs(q); + blk_mq_sysfs_unregister(q); + } + + prev_nr_hw_queues = set->nr_hw_queues; set->nr_hw_queues = nr_hw_queues; blk_mq_update_queue_map(set); +fallback: list_for_each_entry(q, &set->tag_list, tag_set_list) { blk_mq_realloc_hw_ctxs(set, q); - blk_mq_queue_reinit(q); + if (q->nr_hw_queues != set->nr_hw_queues) { + pr_warn("Increasing nr_hw_queues to %d fails, fallback to %d\n", + nr_hw_queues, prev_nr_hw_queues); + set->nr_hw_queues = prev_nr_hw_queues; + blk_mq_map_queues(set); + goto fallback; + } + blk_mq_map_swqueue(q); + } + + list_for_each_entry(q, &set->tag_list, tag_set_list) { + blk_mq_sysfs_register(q); + blk_mq_debugfs_register_hctxs(q); } switch_back: diff --git a/block/blk-pm.c b/block/blk-pm.c new file mode 100644 index 000000000000..f8fdae01bea2 --- /dev/null +++ b/block/blk-pm.c @@ -0,0 +1,216 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/blk-mq.h> +#include <linux/blk-pm.h> +#include <linux/blkdev.h> +#include <linux/pm_runtime.h> +#include "blk-mq.h" +#include "blk-mq-tag.h" + +/** + * blk_pm_runtime_init - Block layer runtime PM initialization routine + * @q: the queue of the device + * @dev: the device the queue belongs to + * + * Description: + * Initialize runtime-PM-related fields for @q and start auto suspend for + * @dev. Drivers that want to take advantage of request-based runtime PM + * should call this function after @dev has been initialized, and its + * request queue @q has been allocated, and runtime PM for it can not happen + * yet(either due to disabled/forbidden or its usage_count > 0). In most + * cases, driver should call this function before any I/O has taken place. + * + * This function takes care of setting up using auto suspend for the device, + * the autosuspend delay is set to -1 to make runtime suspend impossible + * until an updated value is either set by user or by driver. Drivers do + * not need to touch other autosuspend settings. + * + * The block layer runtime PM is request based, so only works for drivers + * that use request as their IO unit instead of those directly use bio's. + */ +void blk_pm_runtime_init(struct request_queue *q, struct device *dev) +{ + q->dev = dev; + q->rpm_status = RPM_ACTIVE; + pm_runtime_set_autosuspend_delay(q->dev, -1); + pm_runtime_use_autosuspend(q->dev); +} +EXPORT_SYMBOL(blk_pm_runtime_init); + +/** + * blk_pre_runtime_suspend - Pre runtime suspend check + * @q: the queue of the device + * + * Description: + * This function will check if runtime suspend is allowed for the device + * by examining if there are any requests pending in the queue. If there + * are requests pending, the device can not be runtime suspended; otherwise, + * the queue's status will be updated to SUSPENDING and the driver can + * proceed to suspend the device. + * + * For the not allowed case, we mark last busy for the device so that + * runtime PM core will try to autosuspend it some time later. + * + * This function should be called near the start of the device's + * runtime_suspend callback. + * + * Return: + * 0 - OK to runtime suspend the device + * -EBUSY - Device should not be runtime suspended + */ +int blk_pre_runtime_suspend(struct request_queue *q) +{ + int ret = 0; + + if (!q->dev) + return ret; + + WARN_ON_ONCE(q->rpm_status != RPM_ACTIVE); + + /* + * Increase the pm_only counter before checking whether any + * non-PM blk_queue_enter() calls are in progress to avoid that any + * new non-PM blk_queue_enter() calls succeed before the pm_only + * counter is decreased again. + */ + blk_set_pm_only(q); + ret = -EBUSY; + /* Switch q_usage_counter from per-cpu to atomic mode. */ + blk_freeze_queue_start(q); + /* + * Wait until atomic mode has been reached. Since that + * involves calling call_rcu(), it is guaranteed that later + * blk_queue_enter() calls see the pm-only state. See also + * http://lwn.net/Articles/573497/. + */ + percpu_ref_switch_to_atomic_sync(&q->q_usage_counter); + if (percpu_ref_is_zero(&q->q_usage_counter)) + ret = 0; + /* Switch q_usage_counter back to per-cpu mode. */ + blk_mq_unfreeze_queue(q); + + spin_lock_irq(q->queue_lock); + if (ret < 0) + pm_runtime_mark_last_busy(q->dev); + else + q->rpm_status = RPM_SUSPENDING; + spin_unlock_irq(q->queue_lock); + + if (ret) + blk_clear_pm_only(q); + + return ret; +} +EXPORT_SYMBOL(blk_pre_runtime_suspend); + +/** + * blk_post_runtime_suspend - Post runtime suspend processing + * @q: the queue of the device + * @err: return value of the device's runtime_suspend function + * + * Description: + * Update the queue's runtime status according to the return value of the + * device's runtime suspend function and mark last busy for the device so + * that PM core will try to auto suspend the device at a later time. + * + * This function should be called near the end of the device's + * runtime_suspend callback. + */ +void blk_post_runtime_suspend(struct request_queue *q, int err) +{ + if (!q->dev) + return; + + spin_lock_irq(q->queue_lock); + if (!err) { + q->rpm_status = RPM_SUSPENDED; + } else { + q->rpm_status = RPM_ACTIVE; + pm_runtime_mark_last_busy(q->dev); + } + spin_unlock_irq(q->queue_lock); + + if (err) + blk_clear_pm_only(q); +} +EXPORT_SYMBOL(blk_post_runtime_suspend); + +/** + * blk_pre_runtime_resume - Pre runtime resume processing + * @q: the queue of the device + * + * Description: + * Update the queue's runtime status to RESUMING in preparation for the + * runtime resume of the device. + * + * This function should be called near the start of the device's + * runtime_resume callback. + */ +void blk_pre_runtime_resume(struct request_queue *q) +{ + if (!q->dev) + return; + + spin_lock_irq(q->queue_lock); + q->rpm_status = RPM_RESUMING; + spin_unlock_irq(q->queue_lock); +} +EXPORT_SYMBOL(blk_pre_runtime_resume); + +/** + * blk_post_runtime_resume - Post runtime resume processing + * @q: the queue of the device + * @err: return value of the device's runtime_resume function + * + * Description: + * Update the queue's runtime status according to the return value of the + * device's runtime_resume function. If it is successfully resumed, process + * the requests that are queued into the device's queue when it is resuming + * and then mark last busy and initiate autosuspend for it. + * + * This function should be called near the end of the device's + * runtime_resume callback. + */ +void blk_post_runtime_resume(struct request_queue *q, int err) +{ + if (!q->dev) + return; + + spin_lock_irq(q->queue_lock); + if (!err) { + q->rpm_status = RPM_ACTIVE; + pm_runtime_mark_last_busy(q->dev); + pm_request_autosuspend(q->dev); + } else { + q->rpm_status = RPM_SUSPENDED; + } + spin_unlock_irq(q->queue_lock); + + if (!err) + blk_clear_pm_only(q); +} +EXPORT_SYMBOL(blk_post_runtime_resume); + +/** + * blk_set_runtime_active - Force runtime status of the queue to be active + * @q: the queue of the device + * + * If the device is left runtime suspended during system suspend the resume + * hook typically resumes the device and corrects runtime status + * accordingly. However, that does not affect the queue runtime PM status + * which is still "suspended". This prevents processing requests from the + * queue. + * + * This function can be used in driver's resume hook to correct queue + * runtime PM status and re-enable peeking requests from the queue. It + * should be called before first request is added to the queue. + */ +void blk_set_runtime_active(struct request_queue *q) +{ + spin_lock_irq(q->queue_lock); + q->rpm_status = RPM_ACTIVE; + pm_runtime_mark_last_busy(q->dev); + pm_request_autosuspend(q->dev); + spin_unlock_irq(q->queue_lock); +} +EXPORT_SYMBOL(blk_set_runtime_active); diff --git a/block/blk-pm.h b/block/blk-pm.h new file mode 100644 index 000000000000..a8564ea72a41 --- /dev/null +++ b/block/blk-pm.h @@ -0,0 +1,69 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _BLOCK_BLK_PM_H_ +#define _BLOCK_BLK_PM_H_ + +#include <linux/pm_runtime.h> + +#ifdef CONFIG_PM +static inline void blk_pm_request_resume(struct request_queue *q) +{ + if (q->dev && (q->rpm_status == RPM_SUSPENDED || + q->rpm_status == RPM_SUSPENDING)) + pm_request_resume(q->dev); +} + +static inline void blk_pm_mark_last_busy(struct request *rq) +{ + if (rq->q->dev && !(rq->rq_flags & RQF_PM)) + pm_runtime_mark_last_busy(rq->q->dev); +} + +static inline void blk_pm_requeue_request(struct request *rq) +{ + lockdep_assert_held(rq->q->queue_lock); + + if (rq->q->dev && !(rq->rq_flags & RQF_PM)) + rq->q->nr_pending--; +} + +static inline void blk_pm_add_request(struct request_queue *q, + struct request *rq) +{ + lockdep_assert_held(q->queue_lock); + + if (q->dev && !(rq->rq_flags & RQF_PM)) + q->nr_pending++; +} + +static inline void blk_pm_put_request(struct request *rq) +{ + lockdep_assert_held(rq->q->queue_lock); + + if (rq->q->dev && !(rq->rq_flags & RQF_PM)) + --rq->q->nr_pending; +} +#else +static inline void blk_pm_request_resume(struct request_queue *q) +{ +} + +static inline void blk_pm_mark_last_busy(struct request *rq) +{ +} + +static inline void blk_pm_requeue_request(struct request *rq) +{ +} + +static inline void blk_pm_add_request(struct request_queue *q, + struct request *rq) +{ +} + +static inline void blk_pm_put_request(struct request *rq) +{ +} +#endif + +#endif /* _BLOCK_BLK_PM_H_ */ diff --git a/block/blk-settings.c b/block/blk-settings.c index ffd459969689..696c04c1ab6c 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -6,7 +6,7 @@ #include <linux/init.h> #include <linux/bio.h> #include <linux/blkdev.h> -#include <linux/bootmem.h> /* for max_pfn/max_low_pfn */ +#include <linux/memblock.h> /* for max_pfn/max_low_pfn */ #include <linux/gcd.h> #include <linux/lcm.h> #include <linux/jiffies.h> diff --git a/block/blk-softirq.c b/block/blk-softirq.c index 15c1f5e12eb8..e47a2f751884 100644 --- a/block/blk-softirq.c +++ b/block/blk-softirq.c @@ -97,8 +97,8 @@ static int blk_softirq_cpu_dead(unsigned int cpu) void __blk_complete_request(struct request *req) { - int ccpu, cpu; struct request_queue *q = req->q; + int cpu, ccpu = q->mq_ops ? req->mq_ctx->cpu : req->cpu; unsigned long flags; bool shared = false; @@ -110,8 +110,7 @@ void __blk_complete_request(struct request *req) /* * Select completion CPU */ - if (req->cpu != -1) { - ccpu = req->cpu; + if (test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags) && ccpu != -1) { if (!test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags)) shared = cpus_share_cache(cpu, ccpu); } else diff --git a/block/blk-stat.c b/block/blk-stat.c index 7587b1c3caaf..90561af85a62 100644 --- a/block/blk-stat.c +++ b/block/blk-stat.c @@ -190,6 +190,7 @@ void blk_stat_enable_accounting(struct request_queue *q) blk_queue_flag_set(QUEUE_FLAG_STATS, q); spin_unlock(&q->stats->lock); } +EXPORT_SYMBOL_GPL(blk_stat_enable_accounting); struct blk_queue_stats *blk_alloc_queue_stats(void) { diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 3772671cf2bc..844a454a7b3a 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -300,6 +300,11 @@ static ssize_t queue_zoned_show(struct request_queue *q, char *page) } } +static ssize_t queue_nr_zones_show(struct request_queue *q, char *page) +{ + return queue_var_show(blk_queue_nr_zones(q), page); +} + static ssize_t queue_nomerges_show(struct request_queue *q, char *page) { return queue_var_show((blk_queue_nomerges(q) << 1) | @@ -637,6 +642,11 @@ static struct queue_sysfs_entry queue_zoned_entry = { .show = queue_zoned_show, }; +static struct queue_sysfs_entry queue_nr_zones_entry = { + .attr = {.name = "nr_zones", .mode = 0444 }, + .show = queue_nr_zones_show, +}; + static struct queue_sysfs_entry queue_nomerges_entry = { .attr = {.name = "nomerges", .mode = 0644 }, .show = queue_nomerges_show, @@ -727,6 +737,7 @@ static struct attribute *default_attrs[] = { &queue_write_zeroes_max_entry.attr, &queue_nonrot_entry.attr, &queue_zoned_entry.attr, + &queue_nr_zones_entry.attr, &queue_nomerges_entry.attr, &queue_rq_affinity_entry.attr, &queue_iostats_entry.attr, @@ -841,6 +852,8 @@ static void __blk_release_queue(struct work_struct *work) if (q->queue_tags) __blk_queue_free_tags(q); + blk_queue_free_zone_bitmaps(q); + if (!q->mq_ops) { if (q->exit_rq_fn) q->exit_rq_fn(q, q->fq->flush_rq); @@ -994,8 +1007,6 @@ void blk_unregister_queue(struct gendisk *disk) kobject_del(&q->kobj); blk_trace_remove_sysfs(disk_to_dev(disk)); - rq_qos_exit(q); - mutex_lock(&q->sysfs_lock); if (q->request_fn || (q->mq_ops && q->elevator)) elv_unregister_queue(q); diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 01d0620a4e4a..db1a3a2ae006 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -84,8 +84,7 @@ struct throtl_service_queue { * RB tree of active children throtl_grp's, which are sorted by * their ->disptime. */ - struct rb_root pending_tree; /* RB tree of active tgs */ - struct rb_node *first_pending; /* first node in the tree */ + struct rb_root_cached pending_tree; /* RB tree of active tgs */ unsigned int nr_pending; /* # queued in the tree */ unsigned long first_pending_disptime; /* disptime of the first tg */ struct timer_list pending_timer; /* fires on first_pending_disptime */ @@ -475,7 +474,7 @@ static void throtl_service_queue_init(struct throtl_service_queue *sq) { INIT_LIST_HEAD(&sq->queued[0]); INIT_LIST_HEAD(&sq->queued[1]); - sq->pending_tree = RB_ROOT; + sq->pending_tree = RB_ROOT_CACHED; timer_setup(&sq->pending_timer, throtl_pending_timer_fn, 0); } @@ -616,31 +615,23 @@ static void throtl_pd_free(struct blkg_policy_data *pd) static struct throtl_grp * throtl_rb_first(struct throtl_service_queue *parent_sq) { + struct rb_node *n; /* Service tree is empty */ if (!parent_sq->nr_pending) return NULL; - if (!parent_sq->first_pending) - parent_sq->first_pending = rb_first(&parent_sq->pending_tree); - - if (parent_sq->first_pending) - return rb_entry_tg(parent_sq->first_pending); - - return NULL; -} - -static void rb_erase_init(struct rb_node *n, struct rb_root *root) -{ - rb_erase(n, root); - RB_CLEAR_NODE(n); + n = rb_first_cached(&parent_sq->pending_tree); + WARN_ON_ONCE(!n); + if (!n) + return NULL; + return rb_entry_tg(n); } static void throtl_rb_erase(struct rb_node *n, struct throtl_service_queue *parent_sq) { - if (parent_sq->first_pending == n) - parent_sq->first_pending = NULL; - rb_erase_init(n, &parent_sq->pending_tree); + rb_erase_cached(n, &parent_sq->pending_tree); + RB_CLEAR_NODE(n); --parent_sq->nr_pending; } @@ -658,11 +649,11 @@ static void update_min_dispatch_time(struct throtl_service_queue *parent_sq) static void tg_service_queue_add(struct throtl_grp *tg) { struct throtl_service_queue *parent_sq = tg->service_queue.parent_sq; - struct rb_node **node = &parent_sq->pending_tree.rb_node; + struct rb_node **node = &parent_sq->pending_tree.rb_root.rb_node; struct rb_node *parent = NULL; struct throtl_grp *__tg; unsigned long key = tg->disptime; - int left = 1; + bool leftmost = true; while (*node != NULL) { parent = *node; @@ -672,15 +663,13 @@ static void tg_service_queue_add(struct throtl_grp *tg) node = &parent->rb_left; else { node = &parent->rb_right; - left = 0; + leftmost = false; } } - if (left) - parent_sq->first_pending = &tg->rb_node; - rb_link_node(&tg->rb_node, parent, node); - rb_insert_color(&tg->rb_node, &parent_sq->pending_tree); + rb_insert_color_cached(&tg->rb_node, &parent_sq->pending_tree, + leftmost); } static void __throtl_enqueue_tg(struct throtl_grp *tg) diff --git a/block/blk-wbt.c b/block/blk-wbt.c index 8e20a0677dcf..8ac93fcbaa2e 100644 --- a/block/blk-wbt.c +++ b/block/blk-wbt.c @@ -310,6 +310,7 @@ static void scale_up(struct rq_wb *rwb) rq_depth_scale_up(&rwb->rq_depth); calc_wb_limits(rwb); rwb->unknown_cnt = 0; + rwb_wake_all(rwb); rwb_trace_step(rwb, "scale up"); } @@ -318,7 +319,6 @@ static void scale_down(struct rq_wb *rwb, bool hard_throttle) rq_depth_scale_down(&rwb->rq_depth, hard_throttle); calc_wb_limits(rwb); rwb->unknown_cnt = 0; - rwb_wake_all(rwb); rwb_trace_step(rwb, "scale down"); } diff --git a/block/blk-zoned.c b/block/blk-zoned.c index c461cf63f1f4..13ba2011a306 100644 --- a/block/blk-zoned.c +++ b/block/blk-zoned.c @@ -12,6 +12,9 @@ #include <linux/module.h> #include <linux/rbtree.h> #include <linux/blkdev.h> +#include <linux/blk-mq.h> + +#include "blk.h" static inline sector_t blk_zone_start(struct request_queue *q, sector_t sector) @@ -63,14 +66,38 @@ void __blk_req_zone_write_unlock(struct request *rq) } EXPORT_SYMBOL_GPL(__blk_req_zone_write_unlock); +static inline unsigned int __blkdev_nr_zones(struct request_queue *q, + sector_t nr_sectors) +{ + unsigned long zone_sectors = blk_queue_zone_sectors(q); + + return (nr_sectors + zone_sectors - 1) >> ilog2(zone_sectors); +} + +/** + * blkdev_nr_zones - Get number of zones + * @bdev: Target block device + * + * Description: + * Return the total number of zones of a zoned block device. + * For a regular block device, the number of zones is always 0. + */ +unsigned int blkdev_nr_zones(struct block_device *bdev) +{ + struct request_queue *q = bdev_get_queue(bdev); + + if (!blk_queue_is_zoned(q)) + return 0; + + return __blkdev_nr_zones(q, bdev->bd_part->nr_sects); +} +EXPORT_SYMBOL_GPL(blkdev_nr_zones); + /* - * Check that a zone report belongs to the partition. - * If yes, fix its start sector and write pointer, copy it in the - * zone information array and return true. Return false otherwise. + * Check that a zone report belongs to this partition, and if yes, fix its start + * sector and write pointer and return true. Return false otherwise. */ -static bool blkdev_report_zone(struct block_device *bdev, - struct blk_zone *rep, - struct blk_zone *zone) +static bool blkdev_report_zone(struct block_device *bdev, struct blk_zone *rep) { sector_t offset = get_start_sect(bdev); @@ -85,11 +112,36 @@ static bool blkdev_report_zone(struct block_device *bdev, rep->wp = rep->start + rep->len; else rep->wp -= offset; - memcpy(zone, rep, sizeof(struct blk_zone)); - return true; } +static int blk_report_zones(struct gendisk *disk, sector_t sector, + struct blk_zone *zones, unsigned int *nr_zones, + gfp_t gfp_mask) +{ + struct request_queue *q = disk->queue; + unsigned int z = 0, n, nrz = *nr_zones; + sector_t capacity = get_capacity(disk); + int ret; + + while (z < nrz && sector < capacity) { + n = nrz - z; + ret = disk->fops->report_zones(disk, sector, &zones[z], &n, + gfp_mask); + if (ret) + return ret; + if (!n) + break; + sector += blk_queue_zone_sectors(q) * n; + z += n; + } + + WARN_ON(z > *nr_zones); + *nr_zones = z; + + return 0; +} + /** * blkdev_report_zones - Get zones information * @bdev: Target block device @@ -104,130 +156,46 @@ static bool blkdev_report_zone(struct block_device *bdev, * requested by @nr_zones. The number of zones actually reported is * returned in @nr_zones. */ -int blkdev_report_zones(struct block_device *bdev, - sector_t sector, - struct blk_zone *zones, - unsigned int *nr_zones, +int blkdev_report_zones(struct block_device *bdev, sector_t sector, + struct blk_zone *zones, unsigned int *nr_zones, gfp_t gfp_mask) { struct request_queue *q = bdev_get_queue(bdev); - struct blk_zone_report_hdr *hdr; - unsigned int nrz = *nr_zones; - struct page *page; - unsigned int nr_rep; - size_t rep_bytes; - unsigned int nr_pages; - struct bio *bio; - struct bio_vec *bv; - unsigned int i, n, nz; - unsigned int ofst; - void *addr; + unsigned int i, nrz; int ret; - if (!q) - return -ENXIO; - if (!blk_queue_is_zoned(q)) return -EOPNOTSUPP; - if (!nrz) - return 0; - - if (sector > bdev->bd_part->nr_sects) { - *nr_zones = 0; - return 0; - } - /* - * The zone report has a header. So make room for it in the - * payload. Also make sure that the report fits in a single BIO - * that will not be split down the stack. + * A block device that advertized itself as zoned must have a + * report_zones method. If it does not have one defined, the device + * driver has a bug. So warn about that. */ - rep_bytes = sizeof(struct blk_zone_report_hdr) + - sizeof(struct blk_zone) * nrz; - rep_bytes = (rep_bytes + PAGE_SIZE - 1) & PAGE_MASK; - if (rep_bytes > (queue_max_sectors(q) << 9)) - rep_bytes = queue_max_sectors(q) << 9; - - nr_pages = min_t(unsigned int, BIO_MAX_PAGES, - rep_bytes >> PAGE_SHIFT); - nr_pages = min_t(unsigned int, nr_pages, - queue_max_segments(q)); - - bio = bio_alloc(gfp_mask, nr_pages); - if (!bio) - return -ENOMEM; - - bio_set_dev(bio, bdev); - bio->bi_iter.bi_sector = blk_zone_start(q, sector); - bio_set_op_attrs(bio, REQ_OP_ZONE_REPORT, 0); + if (WARN_ON_ONCE(!bdev->bd_disk->fops->report_zones)) + return -EOPNOTSUPP; - for (i = 0; i < nr_pages; i++) { - page = alloc_page(gfp_mask); - if (!page) { - ret = -ENOMEM; - goto out; - } - if (!bio_add_page(bio, page, PAGE_SIZE, 0)) { - __free_page(page); - break; - } + if (!*nr_zones || sector >= bdev->bd_part->nr_sects) { + *nr_zones = 0; + return 0; } - if (i == 0) - ret = -ENOMEM; - else - ret = submit_bio_wait(bio); + nrz = min(*nr_zones, + __blkdev_nr_zones(q, bdev->bd_part->nr_sects - sector)); + ret = blk_report_zones(bdev->bd_disk, get_start_sect(bdev) + sector, + zones, &nrz, gfp_mask); if (ret) - goto out; - - /* - * Process the report result: skip the header and go through the - * reported zones to fixup and fixup the zone information for - * partitions. At the same time, return the zone information into - * the zone array. - */ - n = 0; - nz = 0; - nr_rep = 0; - bio_for_each_segment_all(bv, bio, i) { - - if (!bv->bv_page) - break; - - addr = kmap_atomic(bv->bv_page); - - /* Get header in the first page */ - ofst = 0; - if (!nr_rep) { - hdr = addr; - nr_rep = hdr->nr_zones; - ofst = sizeof(struct blk_zone_report_hdr); - } - - /* Fixup and report zones */ - while (ofst < bv->bv_len && - n < nr_rep && nz < nrz) { - if (blkdev_report_zone(bdev, addr + ofst, &zones[nz])) - nz++; - ofst += sizeof(struct blk_zone); - n++; - } - - kunmap_atomic(addr); + return ret; - if (n >= nr_rep || nz >= nrz) + for (i = 0; i < nrz; i++) { + if (!blkdev_report_zone(bdev, zones)) break; - + zones++; } - *nr_zones = nz; -out: - bio_for_each_segment_all(bv, bio, i) - __free_page(bv->bv_page); - bio_put(bio); + *nr_zones = i; - return ret; + return 0; } EXPORT_SYMBOL_GPL(blkdev_report_zones); @@ -250,16 +218,17 @@ int blkdev_reset_zones(struct block_device *bdev, struct request_queue *q = bdev_get_queue(bdev); sector_t zone_sectors; sector_t end_sector = sector + nr_sectors; - struct bio *bio; + struct bio *bio = NULL; + struct blk_plug plug; int ret; - if (!q) - return -ENXIO; - if (!blk_queue_is_zoned(q)) return -EOPNOTSUPP; - if (end_sector > bdev->bd_part->nr_sects) + if (bdev_read_only(bdev)) + return -EPERM; + + if (!nr_sectors || end_sector > bdev->bd_part->nr_sects) /* Out of range */ return -EINVAL; @@ -272,19 +241,14 @@ int blkdev_reset_zones(struct block_device *bdev, end_sector != bdev->bd_part->nr_sects) return -EINVAL; + blk_start_plug(&plug); while (sector < end_sector) { - bio = bio_alloc(gfp_mask, 0); + bio = blk_next_bio(bio, 0, gfp_mask); bio->bi_iter.bi_sector = sector; bio_set_dev(bio, bdev); bio_set_op_attrs(bio, REQ_OP_ZONE_RESET, 0); - ret = submit_bio_wait(bio); - bio_put(bio); - - if (ret) - return ret; - sector += zone_sectors; /* This may take a while, so be nice to others */ @@ -292,7 +256,12 @@ int blkdev_reset_zones(struct block_device *bdev, } - return 0; + ret = submit_bio_wait(bio); + bio_put(bio); + + blk_finish_plug(&plug); + + return ret; } EXPORT_SYMBOL_GPL(blkdev_reset_zones); @@ -328,8 +297,7 @@ int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode, if (!rep.nr_zones) return -EINVAL; - if (rep.nr_zones > INT_MAX / sizeof(struct blk_zone)) - return -ERANGE; + rep.nr_zones = min(blkdev_nr_zones(bdev), rep.nr_zones); zones = kvmalloc_array(rep.nr_zones, sizeof(struct blk_zone), GFP_KERNEL | __GFP_ZERO); @@ -392,3 +360,138 @@ int blkdev_reset_zones_ioctl(struct block_device *bdev, fmode_t mode, return blkdev_reset_zones(bdev, zrange.sector, zrange.nr_sectors, GFP_KERNEL); } + +static inline unsigned long *blk_alloc_zone_bitmap(int node, + unsigned int nr_zones) +{ + return kcalloc_node(BITS_TO_LONGS(nr_zones), sizeof(unsigned long), + GFP_NOIO, node); +} + +/* + * Allocate an array of struct blk_zone to get nr_zones zone information. + * The allocated array may be smaller than nr_zones. + */ +static struct blk_zone *blk_alloc_zones(int node, unsigned int *nr_zones) +{ + size_t size = *nr_zones * sizeof(struct blk_zone); + struct page *page; + int order; + + for (order = get_order(size); order > 0; order--) { + page = alloc_pages_node(node, GFP_NOIO | __GFP_ZERO, order); + if (page) { + *nr_zones = min_t(unsigned int, *nr_zones, + (PAGE_SIZE << order) / sizeof(struct blk_zone)); + return page_address(page); + } + } + + return NULL; +} + +void blk_queue_free_zone_bitmaps(struct request_queue *q) +{ + kfree(q->seq_zones_bitmap); + q->seq_zones_bitmap = NULL; + kfree(q->seq_zones_wlock); + q->seq_zones_wlock = NULL; +} + +/** + * blk_revalidate_disk_zones - (re)allocate and initialize zone bitmaps + * @disk: Target disk + * + * Helper function for low-level device drivers to (re) allocate and initialize + * a disk request queue zone bitmaps. This functions should normally be called + * within the disk ->revalidate method. For BIO based queues, no zone bitmap + * is allocated. + */ +int blk_revalidate_disk_zones(struct gendisk *disk) +{ + struct request_queue *q = disk->queue; + unsigned int nr_zones = __blkdev_nr_zones(q, get_capacity(disk)); + unsigned long *seq_zones_wlock = NULL, *seq_zones_bitmap = NULL; + unsigned int i, rep_nr_zones = 0, z = 0, nrz; + struct blk_zone *zones = NULL; + sector_t sector = 0; + int ret = 0; + + /* + * BIO based queues do not use a scheduler so only q->nr_zones + * needs to be updated so that the sysfs exposed value is correct. + */ + if (!queue_is_rq_based(q)) { + q->nr_zones = nr_zones; + return 0; + } + + if (!blk_queue_is_zoned(q) || !nr_zones) { + nr_zones = 0; + goto update; + } + + /* Allocate bitmaps */ + ret = -ENOMEM; + seq_zones_wlock = blk_alloc_zone_bitmap(q->node, nr_zones); + if (!seq_zones_wlock) + goto out; + seq_zones_bitmap = blk_alloc_zone_bitmap(q->node, nr_zones); + if (!seq_zones_bitmap) + goto out; + + /* Get zone information and initialize seq_zones_bitmap */ + rep_nr_zones = nr_zones; + zones = blk_alloc_zones(q->node, &rep_nr_zones); + if (!zones) + goto out; + + while (z < nr_zones) { + nrz = min(nr_zones - z, rep_nr_zones); + ret = blk_report_zones(disk, sector, zones, &nrz, GFP_NOIO); + if (ret) + goto out; + if (!nrz) + break; + for (i = 0; i < nrz; i++) { + if (zones[i].type != BLK_ZONE_TYPE_CONVENTIONAL) + set_bit(z, seq_zones_bitmap); + z++; + } + sector += nrz * blk_queue_zone_sectors(q); + } + + if (WARN_ON(z != nr_zones)) { + ret = -EIO; + goto out; + } + +update: + /* + * Install the new bitmaps, making sure the queue is stopped and + * all I/Os are completed (i.e. a scheduler is not referencing the + * bitmaps). + */ + blk_mq_freeze_queue(q); + q->nr_zones = nr_zones; + swap(q->seq_zones_wlock, seq_zones_wlock); + swap(q->seq_zones_bitmap, seq_zones_bitmap); + blk_mq_unfreeze_queue(q); + +out: + free_pages((unsigned long)zones, + get_order(rep_nr_zones * sizeof(struct blk_zone))); + kfree(seq_zones_wlock); + kfree(seq_zones_bitmap); + + if (ret) { + pr_warn("%s: failed to revalidate zones\n", disk->disk_name); + blk_mq_freeze_queue(q); + blk_queue_free_zone_bitmaps(q); + blk_mq_unfreeze_queue(q); + } + + return ret; +} +EXPORT_SYMBOL_GPL(blk_revalidate_disk_zones); + diff --git a/block/blk.h b/block/blk.h index 9db4e389582c..a1841b8ff129 100644 --- a/block/blk.h +++ b/block/blk.h @@ -4,6 +4,7 @@ #include <linux/idr.h> #include <linux/blk-mq.h> +#include <xen/xen.h> #include "blk-mq.h" /* Amount of time in which a process may batch requests */ @@ -124,7 +125,7 @@ static inline void __blk_get_queue(struct request_queue *q) } struct blk_flush_queue *blk_alloc_flush_queue(struct request_queue *q, - int node, int cmd_size); + int node, int cmd_size, gfp_t flags); void blk_free_flush_queue(struct blk_flush_queue *q); int blk_init_rl(struct request_list *rl, struct request_queue *q, @@ -149,6 +150,41 @@ static inline void blk_queue_enter_live(struct request_queue *q) percpu_ref_get(&q->q_usage_counter); } +static inline bool biovec_phys_mergeable(struct request_queue *q, + struct bio_vec *vec1, struct bio_vec *vec2) +{ + unsigned long mask = queue_segment_boundary(q); + phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset; + phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset; + + if (addr1 + vec1->bv_len != addr2) + return false; + if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2)) + return false; + if ((addr1 | mask) != ((addr2 + vec2->bv_len - 1) | mask)) + return false; + return true; +} + +static inline bool __bvec_gap_to_prev(struct request_queue *q, + struct bio_vec *bprv, unsigned int offset) +{ + return offset || + ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q)); +} + +/* + * Check if adding a bio_vec after bprv with offset would create a gap in + * the SG list. Most drivers don't care about this, but some do. + */ +static inline bool bvec_gap_to_prev(struct request_queue *q, + struct bio_vec *bprv, unsigned int offset) +{ + if (!queue_virt_boundary(q)) + return false; + return __bvec_gap_to_prev(q, bprv, offset); +} + #ifdef CONFIG_BLK_DEV_INTEGRITY void blk_flush_integrity(void); bool __bio_integrity_endio(struct bio *); @@ -158,7 +194,38 @@ static inline bool bio_integrity_endio(struct bio *bio) return __bio_integrity_endio(bio); return true; } -#else + +static inline bool integrity_req_gap_back_merge(struct request *req, + struct bio *next) +{ + struct bio_integrity_payload *bip = bio_integrity(req->bio); + struct bio_integrity_payload *bip_next = bio_integrity(next); + + return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1], + bip_next->bip_vec[0].bv_offset); +} + +static inline bool integrity_req_gap_front_merge(struct request *req, + struct bio *bio) +{ + struct bio_integrity_payload *bip = bio_integrity(bio); + struct bio_integrity_payload *bip_next = bio_integrity(req->bio); + + return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1], + bip_next->bip_vec[0].bv_offset); +} +#else /* CONFIG_BLK_DEV_INTEGRITY */ +static inline bool integrity_req_gap_back_merge(struct request *req, + struct bio *next) +{ + return false; +} +static inline bool integrity_req_gap_front_merge(struct request *req, + struct bio *bio) +{ + return false; +} + static inline void blk_flush_integrity(void) { } @@ -166,7 +233,7 @@ static inline bool bio_integrity_endio(struct bio *bio) { return true; } -#endif +#endif /* CONFIG_BLK_DEV_INTEGRITY */ void blk_timeout_work(struct work_struct *work); unsigned long blk_rq_timeout(unsigned long timeout); @@ -421,4 +488,12 @@ extern int blk_iolatency_init(struct request_queue *q); static inline int blk_iolatency_init(struct request_queue *q) { return 0; } #endif +struct bio *blk_next_bio(struct bio *bio, unsigned int nr_pages, gfp_t gfp); + +#ifdef CONFIG_BLK_DEV_ZONED +void blk_queue_free_zone_bitmaps(struct request_queue *q); +#else +static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {} +#endif + #endif /* BLK_INTERNAL_H */ diff --git a/block/bounce.c b/block/bounce.c index bc63b3a2d18c..36869afc258c 100644 --- a/block/bounce.c +++ b/block/bounce.c @@ -18,7 +18,7 @@ #include <linux/init.h> #include <linux/hash.h> #include <linux/highmem.h> -#include <linux/bootmem.h> +#include <linux/memblock.h> #include <linux/printk.h> #include <asm/tlbflush.h> @@ -31,6 +31,24 @@ static struct bio_set bounce_bio_set, bounce_bio_split; static mempool_t page_pool, isa_page_pool; +static void init_bounce_bioset(void) +{ + static bool bounce_bs_setup; + int ret; + + if (bounce_bs_setup) + return; + + ret = bioset_init(&bounce_bio_set, BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS); + BUG_ON(ret); + if (bioset_integrity_create(&bounce_bio_set, BIO_POOL_SIZE)) + BUG_ON(1); + + ret = bioset_init(&bounce_bio_split, BIO_POOL_SIZE, 0, 0); + BUG_ON(ret); + bounce_bs_setup = true; +} + #if defined(CONFIG_HIGHMEM) static __init int init_emergency_pool(void) { @@ -44,14 +62,7 @@ static __init int init_emergency_pool(void) BUG_ON(ret); pr_info("pool size: %d pages\n", POOL_SIZE); - ret = bioset_init(&bounce_bio_set, BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS); - BUG_ON(ret); - if (bioset_integrity_create(&bounce_bio_set, BIO_POOL_SIZE)) - BUG_ON(1); - - ret = bioset_init(&bounce_bio_split, BIO_POOL_SIZE, 0, 0); - BUG_ON(ret); - + init_bounce_bioset(); return 0; } @@ -86,6 +97,8 @@ static void *mempool_alloc_pages_isa(gfp_t gfp_mask, void *data) return mempool_alloc_pages(gfp_mask | GFP_DMA, data); } +static DEFINE_MUTEX(isa_mutex); + /* * gets called "every" time someone init's a queue with BLK_BOUNCE_ISA * as the max address, so check if the pool has already been created. @@ -94,14 +107,20 @@ int init_emergency_isa_pool(void) { int ret; - if (mempool_initialized(&isa_page_pool)) + mutex_lock(&isa_mutex); + + if (mempool_initialized(&isa_page_pool)) { + mutex_unlock(&isa_mutex); return 0; + } ret = mempool_init(&isa_page_pool, ISA_POOL_SIZE, mempool_alloc_pages_isa, mempool_free_pages, (void *) 0); BUG_ON(ret); pr_info("isa pool size: %d pages\n", ISA_POOL_SIZE); + init_bounce_bioset(); + mutex_unlock(&isa_mutex); return 0; } diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 2eb87444b157..ed41aa978c4a 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -1644,14 +1644,20 @@ static void cfq_pd_offline(struct blkg_policy_data *pd) int i; for (i = 0; i < IOPRIO_BE_NR; i++) { - if (cfqg->async_cfqq[0][i]) + if (cfqg->async_cfqq[0][i]) { cfq_put_queue(cfqg->async_cfqq[0][i]); - if (cfqg->async_cfqq[1][i]) + cfqg->async_cfqq[0][i] = NULL; + } + if (cfqg->async_cfqq[1][i]) { cfq_put_queue(cfqg->async_cfqq[1][i]); + cfqg->async_cfqq[1][i] = NULL; + } } - if (cfqg->async_idle_cfqq) + if (cfqg->async_idle_cfqq) { cfq_put_queue(cfqg->async_idle_cfqq); + cfqg->async_idle_cfqq = NULL; + } /* * @blkg is going offline and will be ignored by diff --git a/block/elevator.c b/block/elevator.c index fae58b2f906f..8fdcd64ae12e 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -41,6 +41,7 @@ #include "blk.h" #include "blk-mq-sched.h" +#include "blk-pm.h" #include "blk-wbt.h" static DEFINE_SPINLOCK(elv_list_lock); @@ -557,27 +558,6 @@ void elv_bio_merged(struct request_queue *q, struct request *rq, e->type->ops.sq.elevator_bio_merged_fn(q, rq, bio); } -#ifdef CONFIG_PM -static void blk_pm_requeue_request(struct request *rq) -{ - if (rq->q->dev && !(rq->rq_flags & RQF_PM)) - rq->q->nr_pending--; -} - -static void blk_pm_add_request(struct request_queue *q, struct request *rq) -{ - if (q->dev && !(rq->rq_flags & RQF_PM) && q->nr_pending++ == 0 && - (q->rpm_status == RPM_SUSPENDED || q->rpm_status == RPM_SUSPENDING)) - pm_request_resume(q->dev); -} -#else -static inline void blk_pm_requeue_request(struct request *rq) {} -static inline void blk_pm_add_request(struct request_queue *q, - struct request *rq) -{ -} -#endif - void elv_requeue_request(struct request_queue *q, struct request *rq) { /* diff --git a/block/genhd.c b/block/genhd.c index be5bab20b2ab..cff6bdf27226 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -567,7 +567,8 @@ static int exact_lock(dev_t devt, void *data) return 0; } -static void register_disk(struct device *parent, struct gendisk *disk) +static void register_disk(struct device *parent, struct gendisk *disk, + const struct attribute_group **groups) { struct device *ddev = disk_to_dev(disk); struct block_device *bdev; @@ -582,6 +583,10 @@ static void register_disk(struct device *parent, struct gendisk *disk) /* delay uevents, until we scanned partition table */ dev_set_uevent_suppress(ddev, 1); + if (groups) { + WARN_ON(ddev->groups); + ddev->groups = groups; + } if (device_add(ddev)) return; if (!sysfs_deprecated) { @@ -647,6 +652,7 @@ exit: * __device_add_disk - add disk information to kernel list * @parent: parent device for the disk * @disk: per-device partitioning information + * @groups: Additional per-device sysfs groups * @register_queue: register the queue if set to true * * This function registers the partitioning information in @disk @@ -655,6 +661,7 @@ exit: * FIXME: error handling */ static void __device_add_disk(struct device *parent, struct gendisk *disk, + const struct attribute_group **groups, bool register_queue) { dev_t devt; @@ -698,7 +705,7 @@ static void __device_add_disk(struct device *parent, struct gendisk *disk, blk_register_region(disk_devt(disk), disk->minors, NULL, exact_match, exact_lock, disk); } - register_disk(parent, disk); + register_disk(parent, disk, groups); if (register_queue) blk_register_queue(disk); @@ -712,15 +719,17 @@ static void __device_add_disk(struct device *parent, struct gendisk *disk, blk_integrity_add(disk); } -void device_add_disk(struct device *parent, struct gendisk *disk) +void device_add_disk(struct device *parent, struct gendisk *disk, + const struct attribute_group **groups) + { - __device_add_disk(parent, disk, true); + __device_add_disk(parent, disk, groups, true); } EXPORT_SYMBOL(device_add_disk); void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk) { - __device_add_disk(parent, disk, false); + __device_add_disk(parent, disk, NULL, false); } EXPORT_SYMBOL(device_add_disk_no_queue_reg); diff --git a/block/ioctl.c b/block/ioctl.c index 3884d810efd2..4825c78a6baa 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -532,6 +532,10 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, return blkdev_report_zones_ioctl(bdev, mode, cmd, arg); case BLKRESETZONE: return blkdev_reset_zones_ioctl(bdev, mode, cmd, arg); + case BLKGETZONESZ: + return put_uint(arg, bdev_zone_sectors(bdev)); + case BLKGETNRZONES: + return put_uint(arg, blkdev_nr_zones(bdev)); case HDIO_GETGEO: return blkdev_getgeo(bdev, argp); case BLKRAGET: diff --git a/block/kyber-iosched.c b/block/kyber-iosched.c index a1660bafc912..eccac01a10b6 100644 --- a/block/kyber-iosched.c +++ b/block/kyber-iosched.c @@ -29,19 +29,30 @@ #include "blk-mq-debugfs.h" #include "blk-mq-sched.h" #include "blk-mq-tag.h" -#include "blk-stat.h" -/* Scheduling domains. */ +#define CREATE_TRACE_POINTS +#include <trace/events/kyber.h> + +/* + * Scheduling domains: the device is divided into multiple domains based on the + * request type. + */ enum { KYBER_READ, - KYBER_SYNC_WRITE, - KYBER_OTHER, /* Async writes, discard, etc. */ + KYBER_WRITE, + KYBER_DISCARD, + KYBER_OTHER, KYBER_NUM_DOMAINS, }; -enum { - KYBER_MIN_DEPTH = 256, +static const char *kyber_domain_names[] = { + [KYBER_READ] = "READ", + [KYBER_WRITE] = "WRITE", + [KYBER_DISCARD] = "DISCARD", + [KYBER_OTHER] = "OTHER", +}; +enum { /* * In order to prevent starvation of synchronous requests by a flood of * asynchronous requests, we reserve 25% of requests for synchronous @@ -51,25 +62,87 @@ enum { }; /* - * Initial device-wide depths for each scheduling domain. + * Maximum device-wide depth for each scheduling domain. * - * Even for fast devices with lots of tags like NVMe, you can saturate - * the device with only a fraction of the maximum possible queue depth. - * So, we cap these to a reasonable value. + * Even for fast devices with lots of tags like NVMe, you can saturate the + * device with only a fraction of the maximum possible queue depth. So, we cap + * these to a reasonable value. */ static const unsigned int kyber_depth[] = { [KYBER_READ] = 256, - [KYBER_SYNC_WRITE] = 128, - [KYBER_OTHER] = 64, + [KYBER_WRITE] = 128, + [KYBER_DISCARD] = 64, + [KYBER_OTHER] = 16, }; /* - * Scheduling domain batch sizes. We favor reads. + * Default latency targets for each scheduling domain. + */ +static const u64 kyber_latency_targets[] = { + [KYBER_READ] = 2ULL * NSEC_PER_MSEC, + [KYBER_WRITE] = 10ULL * NSEC_PER_MSEC, + [KYBER_DISCARD] = 5ULL * NSEC_PER_SEC, +}; + +/* + * Batch size (number of requests we'll dispatch in a row) for each scheduling + * domain. */ static const unsigned int kyber_batch_size[] = { [KYBER_READ] = 16, - [KYBER_SYNC_WRITE] = 8, - [KYBER_OTHER] = 8, + [KYBER_WRITE] = 8, + [KYBER_DISCARD] = 1, + [KYBER_OTHER] = 1, +}; + +/* + * Requests latencies are recorded in a histogram with buckets defined relative + * to the target latency: + * + * <= 1/4 * target latency + * <= 1/2 * target latency + * <= 3/4 * target latency + * <= target latency + * <= 1 1/4 * target latency + * <= 1 1/2 * target latency + * <= 1 3/4 * target latency + * > 1 3/4 * target latency + */ +enum { + /* + * The width of the latency histogram buckets is + * 1 / (1 << KYBER_LATENCY_SHIFT) * target latency. + */ + KYBER_LATENCY_SHIFT = 2, + /* + * The first (1 << KYBER_LATENCY_SHIFT) buckets are <= target latency, + * thus, "good". + */ + KYBER_GOOD_BUCKETS = 1 << KYBER_LATENCY_SHIFT, + /* There are also (1 << KYBER_LATENCY_SHIFT) "bad" buckets. */ + KYBER_LATENCY_BUCKETS = 2 << KYBER_LATENCY_SHIFT, +}; + +/* + * We measure both the total latency and the I/O latency (i.e., latency after + * submitting to the device). + */ +enum { + KYBER_TOTAL_LATENCY, + KYBER_IO_LATENCY, +}; + +static const char *kyber_latency_type_names[] = { + [KYBER_TOTAL_LATENCY] = "total", + [KYBER_IO_LATENCY] = "I/O", +}; + +/* + * Per-cpu latency histograms: total latency and I/O latency for each scheduling + * domain except for KYBER_OTHER. + */ +struct kyber_cpu_latency { + atomic_t buckets[KYBER_OTHER][2][KYBER_LATENCY_BUCKETS]; }; /* @@ -88,12 +161,9 @@ struct kyber_ctx_queue { struct kyber_queue_data { struct request_queue *q; - struct blk_stat_callback *cb; - /* - * The device is divided into multiple scheduling domains based on the - * request type. Each domain has a fixed number of in-flight requests of - * that type device-wide, limited by these tokens. + * Each scheduling domain has a limited number of in-flight requests + * device-wide, limited by these tokens. */ struct sbitmap_queue domain_tokens[KYBER_NUM_DOMAINS]; @@ -103,8 +173,19 @@ struct kyber_queue_data { */ unsigned int async_depth; + struct kyber_cpu_latency __percpu *cpu_latency; + + /* Timer for stats aggregation and adjusting domain tokens. */ + struct timer_list timer; + + unsigned int latency_buckets[KYBER_OTHER][2][KYBER_LATENCY_BUCKETS]; + + unsigned long latency_timeout[KYBER_OTHER]; + + int domain_p99[KYBER_OTHER]; + /* Target latencies in nanoseconds. */ - u64 read_lat_nsec, write_lat_nsec; + u64 latency_targets[KYBER_OTHER]; }; struct kyber_hctx_data { @@ -124,233 +205,219 @@ static int kyber_domain_wake(wait_queue_entry_t *wait, unsigned mode, int flags, static unsigned int kyber_sched_domain(unsigned int op) { - if ((op & REQ_OP_MASK) == REQ_OP_READ) + switch (op & REQ_OP_MASK) { + case REQ_OP_READ: return KYBER_READ; - else if ((op & REQ_OP_MASK) == REQ_OP_WRITE && op_is_sync(op)) - return KYBER_SYNC_WRITE; - else + case REQ_OP_WRITE: + return KYBER_WRITE; + case REQ_OP_DISCARD: + return KYBER_DISCARD; + default: return KYBER_OTHER; + } } -enum { - NONE = 0, - GOOD = 1, - GREAT = 2, - BAD = -1, - AWFUL = -2, -}; - -#define IS_GOOD(status) ((status) > 0) -#define IS_BAD(status) ((status) < 0) - -static int kyber_lat_status(struct blk_stat_callback *cb, - unsigned int sched_domain, u64 target) +static void flush_latency_buckets(struct kyber_queue_data *kqd, + struct kyber_cpu_latency *cpu_latency, + unsigned int sched_domain, unsigned int type) { - u64 latency; - - if (!cb->stat[sched_domain].nr_samples) - return NONE; + unsigned int *buckets = kqd->latency_buckets[sched_domain][type]; + atomic_t *cpu_buckets = cpu_latency->buckets[sched_domain][type]; + unsigned int bucket; - latency = cb->stat[sched_domain].mean; - if (latency >= 2 * target) - return AWFUL; - else if (latency > target) - return BAD; - else if (latency <= target / 2) - return GREAT; - else /* (latency <= target) */ - return GOOD; + for (bucket = 0; bucket < KYBER_LATENCY_BUCKETS; bucket++) + buckets[bucket] += atomic_xchg(&cpu_buckets[bucket], 0); } /* - * Adjust the read or synchronous write depth given the status of reads and - * writes. The goal is that the latencies of the two domains are fair (i.e., if - * one is good, then the other is good). + * Calculate the histogram bucket with the given percentile rank, or -1 if there + * aren't enough samples yet. */ -static void kyber_adjust_rw_depth(struct kyber_queue_data *kqd, - unsigned int sched_domain, int this_status, - int other_status) +static int calculate_percentile(struct kyber_queue_data *kqd, + unsigned int sched_domain, unsigned int type, + unsigned int percentile) { - unsigned int orig_depth, depth; + unsigned int *buckets = kqd->latency_buckets[sched_domain][type]; + unsigned int bucket, samples = 0, percentile_samples; + + for (bucket = 0; bucket < KYBER_LATENCY_BUCKETS; bucket++) + samples += buckets[bucket]; + + if (!samples) + return -1; /* - * If this domain had no samples, or reads and writes are both good or - * both bad, don't adjust the depth. + * We do the calculation once we have 500 samples or one second passes + * since the first sample was recorded, whichever comes first. */ - if (this_status == NONE || - (IS_GOOD(this_status) && IS_GOOD(other_status)) || - (IS_BAD(this_status) && IS_BAD(other_status))) - return; - - orig_depth = depth = kqd->domain_tokens[sched_domain].sb.depth; + if (!kqd->latency_timeout[sched_domain]) + kqd->latency_timeout[sched_domain] = max(jiffies + HZ, 1UL); + if (samples < 500 && + time_is_after_jiffies(kqd->latency_timeout[sched_domain])) { + return -1; + } + kqd->latency_timeout[sched_domain] = 0; - if (other_status == NONE) { - depth++; - } else { - switch (this_status) { - case GOOD: - if (other_status == AWFUL) - depth -= max(depth / 4, 1U); - else - depth -= max(depth / 8, 1U); - break; - case GREAT: - if (other_status == AWFUL) - depth /= 2; - else - depth -= max(depth / 4, 1U); + percentile_samples = DIV_ROUND_UP(samples * percentile, 100); + for (bucket = 0; bucket < KYBER_LATENCY_BUCKETS - 1; bucket++) { + if (buckets[bucket] >= percentile_samples) break; - case BAD: - depth++; - break; - case AWFUL: - if (other_status == GREAT) - depth += 2; - else - depth++; - break; - } + percentile_samples -= buckets[bucket]; } + memset(buckets, 0, sizeof(kqd->latency_buckets[sched_domain][type])); - depth = clamp(depth, 1U, kyber_depth[sched_domain]); - if (depth != orig_depth) - sbitmap_queue_resize(&kqd->domain_tokens[sched_domain], depth); + trace_kyber_latency(kqd->q, kyber_domain_names[sched_domain], + kyber_latency_type_names[type], percentile, + bucket + 1, 1 << KYBER_LATENCY_SHIFT, samples); + + return bucket; } -/* - * Adjust the depth of other requests given the status of reads and synchronous - * writes. As long as either domain is doing fine, we don't throttle, but if - * both domains are doing badly, we throttle heavily. - */ -static void kyber_adjust_other_depth(struct kyber_queue_data *kqd, - int read_status, int write_status, - bool have_samples) -{ - unsigned int orig_depth, depth; - int status; - - orig_depth = depth = kqd->domain_tokens[KYBER_OTHER].sb.depth; - - if (read_status == NONE && write_status == NONE) { - depth += 2; - } else if (have_samples) { - if (read_status == NONE) - status = write_status; - else if (write_status == NONE) - status = read_status; - else - status = max(read_status, write_status); - switch (status) { - case GREAT: - depth += 2; - break; - case GOOD: - depth++; - break; - case BAD: - depth -= max(depth / 4, 1U); - break; - case AWFUL: - depth /= 2; - break; - } +static void kyber_resize_domain(struct kyber_queue_data *kqd, + unsigned int sched_domain, unsigned int depth) +{ + depth = clamp(depth, 1U, kyber_depth[sched_domain]); + if (depth != kqd->domain_tokens[sched_domain].sb.depth) { + sbitmap_queue_resize(&kqd->domain_tokens[sched_domain], depth); + trace_kyber_adjust(kqd->q, kyber_domain_names[sched_domain], + depth); } - - depth = clamp(depth, 1U, kyber_depth[KYBER_OTHER]); - if (depth != orig_depth) - sbitmap_queue_resize(&kqd->domain_tokens[KYBER_OTHER], depth); } -/* - * Apply heuristics for limiting queue depths based on gathered latency - * statistics. - */ -static void kyber_stat_timer_fn(struct blk_stat_callback *cb) +static void kyber_timer_fn(struct timer_list *t) { - struct kyber_queue_data *kqd = cb->data; - int read_status, write_status; + struct kyber_queue_data *kqd = from_timer(kqd, t, timer); + unsigned int sched_domain; + int cpu; + bool bad = false; + + /* Sum all of the per-cpu latency histograms. */ + for_each_online_cpu(cpu) { + struct kyber_cpu_latency *cpu_latency; + + cpu_latency = per_cpu_ptr(kqd->cpu_latency, cpu); + for (sched_domain = 0; sched_domain < KYBER_OTHER; sched_domain++) { + flush_latency_buckets(kqd, cpu_latency, sched_domain, + KYBER_TOTAL_LATENCY); + flush_latency_buckets(kqd, cpu_latency, sched_domain, + KYBER_IO_LATENCY); + } + } - read_status = kyber_lat_status(cb, KYBER_READ, kqd->read_lat_nsec); - write_status = kyber_lat_status(cb, KYBER_SYNC_WRITE, kqd->write_lat_nsec); + /* + * Check if any domains have a high I/O latency, which might indicate + * congestion in the device. Note that we use the p90; we don't want to + * be too sensitive to outliers here. + */ + for (sched_domain = 0; sched_domain < KYBER_OTHER; sched_domain++) { + int p90; - kyber_adjust_rw_depth(kqd, KYBER_READ, read_status, write_status); - kyber_adjust_rw_depth(kqd, KYBER_SYNC_WRITE, write_status, read_status); - kyber_adjust_other_depth(kqd, read_status, write_status, - cb->stat[KYBER_OTHER].nr_samples != 0); + p90 = calculate_percentile(kqd, sched_domain, KYBER_IO_LATENCY, + 90); + if (p90 >= KYBER_GOOD_BUCKETS) + bad = true; + } /* - * Continue monitoring latencies if we aren't hitting the targets or - * we're still throttling other requests. + * Adjust the scheduling domain depths. If we determined that there was + * congestion, we throttle all domains with good latencies. Either way, + * we ease up on throttling domains with bad latencies. */ - if (!blk_stat_is_active(kqd->cb) && - ((IS_BAD(read_status) || IS_BAD(write_status) || - kqd->domain_tokens[KYBER_OTHER].sb.depth < kyber_depth[KYBER_OTHER]))) - blk_stat_activate_msecs(kqd->cb, 100); + for (sched_domain = 0; sched_domain < KYBER_OTHER; sched_domain++) { + unsigned int orig_depth, depth; + int p99; + + p99 = calculate_percentile(kqd, sched_domain, + KYBER_TOTAL_LATENCY, 99); + /* + * This is kind of subtle: different domains will not + * necessarily have enough samples to calculate the latency + * percentiles during the same window, so we have to remember + * the p99 for the next time we observe congestion; once we do, + * we don't want to throttle again until we get more data, so we + * reset it to -1. + */ + if (bad) { + if (p99 < 0) + p99 = kqd->domain_p99[sched_domain]; + kqd->domain_p99[sched_domain] = -1; + } else if (p99 >= 0) { + kqd->domain_p99[sched_domain] = p99; + } + if (p99 < 0) + continue; + + /* + * If this domain has bad latency, throttle less. Otherwise, + * throttle more iff we determined that there is congestion. + * + * The new depth is scaled linearly with the p99 latency vs the + * latency target. E.g., if the p99 is 3/4 of the target, then + * we throttle down to 3/4 of the current depth, and if the p99 + * is 2x the target, then we double the depth. + */ + if (bad || p99 >= KYBER_GOOD_BUCKETS) { + orig_depth = kqd->domain_tokens[sched_domain].sb.depth; + depth = (orig_depth * (p99 + 1)) >> KYBER_LATENCY_SHIFT; + kyber_resize_domain(kqd, sched_domain, depth); + } + } } -static unsigned int kyber_sched_tags_shift(struct kyber_queue_data *kqd) +static unsigned int kyber_sched_tags_shift(struct request_queue *q) { /* * All of the hardware queues have the same depth, so we can just grab * the shift of the first one. */ - return kqd->q->queue_hw_ctx[0]->sched_tags->bitmap_tags.sb.shift; -} - -static int kyber_bucket_fn(const struct request *rq) -{ - return kyber_sched_domain(rq->cmd_flags); + return q->queue_hw_ctx[0]->sched_tags->bitmap_tags.sb.shift; } static struct kyber_queue_data *kyber_queue_data_alloc(struct request_queue *q) { struct kyber_queue_data *kqd; - unsigned int max_tokens; unsigned int shift; int ret = -ENOMEM; int i; - kqd = kmalloc_node(sizeof(*kqd), GFP_KERNEL, q->node); + kqd = kzalloc_node(sizeof(*kqd), GFP_KERNEL, q->node); if (!kqd) goto err; + kqd->q = q; - kqd->cb = blk_stat_alloc_callback(kyber_stat_timer_fn, kyber_bucket_fn, - KYBER_NUM_DOMAINS, kqd); - if (!kqd->cb) + kqd->cpu_latency = alloc_percpu_gfp(struct kyber_cpu_latency, + GFP_KERNEL | __GFP_ZERO); + if (!kqd->cpu_latency) goto err_kqd; - /* - * The maximum number of tokens for any scheduling domain is at least - * the queue depth of a single hardware queue. If the hardware doesn't - * have many tags, still provide a reasonable number. - */ - max_tokens = max_t(unsigned int, q->tag_set->queue_depth, - KYBER_MIN_DEPTH); + timer_setup(&kqd->timer, kyber_timer_fn, 0); + for (i = 0; i < KYBER_NUM_DOMAINS; i++) { WARN_ON(!kyber_depth[i]); WARN_ON(!kyber_batch_size[i]); ret = sbitmap_queue_init_node(&kqd->domain_tokens[i], - max_tokens, -1, false, GFP_KERNEL, - q->node); + kyber_depth[i], -1, false, + GFP_KERNEL, q->node); if (ret) { while (--i >= 0) sbitmap_queue_free(&kqd->domain_tokens[i]); - goto err_cb; + goto err_buckets; } - sbitmap_queue_resize(&kqd->domain_tokens[i], kyber_depth[i]); } - shift = kyber_sched_tags_shift(kqd); - kqd->async_depth = (1U << shift) * KYBER_ASYNC_PERCENT / 100U; + for (i = 0; i < KYBER_OTHER; i++) { + kqd->domain_p99[i] = -1; + kqd->latency_targets[i] = kyber_latency_targets[i]; + } - kqd->read_lat_nsec = 2000000ULL; - kqd->write_lat_nsec = 10000000ULL; + shift = kyber_sched_tags_shift(q); + kqd->async_depth = (1U << shift) * KYBER_ASYNC_PERCENT / 100U; return kqd; -err_cb: - blk_stat_free_callback(kqd->cb); +err_buckets: + free_percpu(kqd->cpu_latency); err_kqd: kfree(kqd); err: @@ -372,25 +439,24 @@ static int kyber_init_sched(struct request_queue *q, struct elevator_type *e) return PTR_ERR(kqd); } + blk_stat_enable_accounting(q); + eq->elevator_data = kqd; q->elevator = eq; - blk_stat_add_callback(q, kqd->cb); - return 0; } static void kyber_exit_sched(struct elevator_queue *e) { struct kyber_queue_data *kqd = e->elevator_data; - struct request_queue *q = kqd->q; int i; - blk_stat_remove_callback(q, kqd->cb); + del_timer_sync(&kqd->timer); for (i = 0; i < KYBER_NUM_DOMAINS; i++) sbitmap_queue_free(&kqd->domain_tokens[i]); - blk_stat_free_callback(kqd->cb); + free_percpu(kqd->cpu_latency); kfree(kqd); } @@ -558,41 +624,44 @@ static void kyber_finish_request(struct request *rq) rq_clear_domain_token(kqd, rq); } -static void kyber_completed_request(struct request *rq) +static void add_latency_sample(struct kyber_cpu_latency *cpu_latency, + unsigned int sched_domain, unsigned int type, + u64 target, u64 latency) { - struct request_queue *q = rq->q; - struct kyber_queue_data *kqd = q->elevator->elevator_data; - unsigned int sched_domain; - u64 now, latency, target; + unsigned int bucket; + u64 divisor; - /* - * Check if this request met our latency goal. If not, quickly gather - * some statistics and start throttling. - */ - sched_domain = kyber_sched_domain(rq->cmd_flags); - switch (sched_domain) { - case KYBER_READ: - target = kqd->read_lat_nsec; - break; - case KYBER_SYNC_WRITE: - target = kqd->write_lat_nsec; - break; - default: - return; + if (latency > 0) { + divisor = max_t(u64, target >> KYBER_LATENCY_SHIFT, 1); + bucket = min_t(unsigned int, div64_u64(latency - 1, divisor), + KYBER_LATENCY_BUCKETS - 1); + } else { + bucket = 0; } - /* If we are already monitoring latencies, don't check again. */ - if (blk_stat_is_active(kqd->cb)) - return; + atomic_inc(&cpu_latency->buckets[sched_domain][type][bucket]); +} - now = ktime_get_ns(); - if (now < rq->io_start_time_ns) +static void kyber_completed_request(struct request *rq, u64 now) +{ + struct kyber_queue_data *kqd = rq->q->elevator->elevator_data; + struct kyber_cpu_latency *cpu_latency; + unsigned int sched_domain; + u64 target; + + sched_domain = kyber_sched_domain(rq->cmd_flags); + if (sched_domain == KYBER_OTHER) return; - latency = now - rq->io_start_time_ns; + cpu_latency = get_cpu_ptr(kqd->cpu_latency); + target = kqd->latency_targets[sched_domain]; + add_latency_sample(cpu_latency, sched_domain, KYBER_TOTAL_LATENCY, + target, now - rq->start_time_ns); + add_latency_sample(cpu_latency, sched_domain, KYBER_IO_LATENCY, target, + now - rq->io_start_time_ns); + put_cpu_ptr(kqd->cpu_latency); - if (latency > target) - blk_stat_activate_msecs(kqd->cb, 10); + timer_reduce(&kqd->timer, jiffies + HZ / 10); } struct flush_kcq_data { @@ -713,6 +782,9 @@ kyber_dispatch_cur_domain(struct kyber_queue_data *kqd, rq_set_domain_token(rq, nr); list_del_init(&rq->queuelist); return rq; + } else { + trace_kyber_throttled(kqd->q, + kyber_domain_names[khd->cur_domain]); } } else if (sbitmap_any_bit_set(&khd->kcq_map[khd->cur_domain])) { nr = kyber_get_domain_token(kqd, khd, hctx); @@ -723,6 +795,9 @@ kyber_dispatch_cur_domain(struct kyber_queue_data *kqd, rq_set_domain_token(rq, nr); list_del_init(&rq->queuelist); return rq; + } else { + trace_kyber_throttled(kqd->q, + kyber_domain_names[khd->cur_domain]); } } @@ -790,17 +865,17 @@ static bool kyber_has_work(struct blk_mq_hw_ctx *hctx) return false; } -#define KYBER_LAT_SHOW_STORE(op) \ -static ssize_t kyber_##op##_lat_show(struct elevator_queue *e, \ - char *page) \ +#define KYBER_LAT_SHOW_STORE(domain, name) \ +static ssize_t kyber_##name##_lat_show(struct elevator_queue *e, \ + char *page) \ { \ struct kyber_queue_data *kqd = e->elevator_data; \ \ - return sprintf(page, "%llu\n", kqd->op##_lat_nsec); \ + return sprintf(page, "%llu\n", kqd->latency_targets[domain]); \ } \ \ -static ssize_t kyber_##op##_lat_store(struct elevator_queue *e, \ - const char *page, size_t count) \ +static ssize_t kyber_##name##_lat_store(struct elevator_queue *e, \ + const char *page, size_t count) \ { \ struct kyber_queue_data *kqd = e->elevator_data; \ unsigned long long nsec; \ @@ -810,12 +885,12 @@ static ssize_t kyber_##op##_lat_store(struct elevator_queue *e, \ if (ret) \ return ret; \ \ - kqd->op##_lat_nsec = nsec; \ + kqd->latency_targets[domain] = nsec; \ \ return count; \ } -KYBER_LAT_SHOW_STORE(read); -KYBER_LAT_SHOW_STORE(write); +KYBER_LAT_SHOW_STORE(KYBER_READ, read); +KYBER_LAT_SHOW_STORE(KYBER_WRITE, write); #undef KYBER_LAT_SHOW_STORE #define KYBER_LAT_ATTR(op) __ATTR(op##_lat_nsec, 0644, kyber_##op##_lat_show, kyber_##op##_lat_store) @@ -882,7 +957,8 @@ static int kyber_##name##_waiting_show(void *data, struct seq_file *m) \ return 0; \ } KYBER_DEBUGFS_DOMAIN_ATTRS(KYBER_READ, read) -KYBER_DEBUGFS_DOMAIN_ATTRS(KYBER_SYNC_WRITE, sync_write) +KYBER_DEBUGFS_DOMAIN_ATTRS(KYBER_WRITE, write) +KYBER_DEBUGFS_DOMAIN_ATTRS(KYBER_DISCARD, discard) KYBER_DEBUGFS_DOMAIN_ATTRS(KYBER_OTHER, other) #undef KYBER_DEBUGFS_DOMAIN_ATTRS @@ -900,20 +976,7 @@ static int kyber_cur_domain_show(void *data, struct seq_file *m) struct blk_mq_hw_ctx *hctx = data; struct kyber_hctx_data *khd = hctx->sched_data; - switch (khd->cur_domain) { - case KYBER_READ: - seq_puts(m, "READ\n"); - break; - case KYBER_SYNC_WRITE: - seq_puts(m, "SYNC_WRITE\n"); - break; - case KYBER_OTHER: - seq_puts(m, "OTHER\n"); - break; - default: - seq_printf(m, "%u\n", khd->cur_domain); - break; - } + seq_printf(m, "%s\n", kyber_domain_names[khd->cur_domain]); return 0; } @@ -930,7 +993,8 @@ static int kyber_batching_show(void *data, struct seq_file *m) {#name "_tokens", 0400, kyber_##name##_tokens_show} static const struct blk_mq_debugfs_attr kyber_queue_debugfs_attrs[] = { KYBER_QUEUE_DOMAIN_ATTRS(read), - KYBER_QUEUE_DOMAIN_ATTRS(sync_write), + KYBER_QUEUE_DOMAIN_ATTRS(write), + KYBER_QUEUE_DOMAIN_ATTRS(discard), KYBER_QUEUE_DOMAIN_ATTRS(other), {"async_depth", 0400, kyber_async_depth_show}, {}, @@ -942,7 +1006,8 @@ static const struct blk_mq_debugfs_attr kyber_queue_debugfs_attrs[] = { {#name "_waiting", 0400, kyber_##name##_waiting_show} static const struct blk_mq_debugfs_attr kyber_hctx_debugfs_attrs[] = { KYBER_HCTX_DOMAIN_ATTRS(read), - KYBER_HCTX_DOMAIN_ATTRS(sync_write), + KYBER_HCTX_DOMAIN_ATTRS(write), + KYBER_HCTX_DOMAIN_ATTRS(discard), KYBER_HCTX_DOMAIN_ATTRS(other), {"cur_domain", 0400, kyber_cur_domain_show}, {"batching", 0400, kyber_batching_show}, |