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block/blk-throttle.c
68.5 KB
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// SPDX-License-Identifier: GPL-2.0 |
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/* * Interface for controlling IO bandwidth on a request queue * * Copyright (C) 2010 Vivek Goyal <vgoyal@redhat.com> */ #include <linux/module.h> #include <linux/slab.h> #include <linux/blkdev.h> #include <linux/bio.h> #include <linux/blktrace_api.h> |
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#include <linux/blk-cgroup.h> |
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#include "blk.h" |
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#include "blk-cgroup-rwstat.h" |
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/* Max dispatch from a group in 1 round */ |
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#define THROTL_GRP_QUANTUM 8 |
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/* Total max dispatch from all groups in one round */ |
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#define THROTL_QUANTUM 32 |
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/* Throttling is performed over a slice and after that slice is renewed */ #define DFL_THROTL_SLICE_HD (HZ / 10) #define DFL_THROTL_SLICE_SSD (HZ / 50) |
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#define MAX_THROTL_SLICE (HZ) |
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#define MAX_IDLE_TIME (5L * 1000 * 1000) /* 5 s */ |
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#define MIN_THROTL_BPS (320 * 1024) #define MIN_THROTL_IOPS (10) |
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#define DFL_LATENCY_TARGET (-1L) #define DFL_IDLE_THRESHOLD (0) |
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#define DFL_HD_BASELINE_LATENCY (4000L) /* 4ms */ #define LATENCY_FILTERED_SSD (0) /* * For HD, very small latency comes from sequential IO. Such IO is helpless to * help determine if its IO is impacted by others, hence we ignore the IO */ #define LATENCY_FILTERED_HD (1000L) /* 1ms */ |
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static struct blkcg_policy blkcg_policy_throtl; |
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/* A workqueue to queue throttle related work */ static struct workqueue_struct *kthrotld_workqueue; |
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/* * To implement hierarchical throttling, throtl_grps form a tree and bios * are dispatched upwards level by level until they reach the top and get * issued. When dispatching bios from the children and local group at each * level, if the bios are dispatched into a single bio_list, there's a risk * of a local or child group which can queue many bios at once filling up * the list starving others. * * To avoid such starvation, dispatched bios are queued separately * according to where they came from. When they are again dispatched to * the parent, they're popped in round-robin order so that no single source * hogs the dispatch window. * * throtl_qnode is used to keep the queued bios separated by their sources. * Bios are queued to throtl_qnode which in turn is queued to * throtl_service_queue and then dispatched in round-robin order. * * It's also used to track the reference counts on blkg's. A qnode always * belongs to a throtl_grp and gets queued on itself or the parent, so * incrementing the reference of the associated throtl_grp when a qnode is * queued and decrementing when dequeued is enough to keep the whole blkg * tree pinned while bios are in flight. */ struct throtl_qnode { struct list_head node; /* service_queue->queued[] */ struct bio_list bios; /* queued bios */ struct throtl_grp *tg; /* tg this qnode belongs to */ }; |
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struct throtl_service_queue { |
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struct throtl_service_queue *parent_sq; /* the parent service_queue */ |
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/* * Bios queued directly to this service_queue or dispatched from * children throtl_grp's. */ |
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struct list_head queued[2]; /* throtl_qnode [READ/WRITE] */ |
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unsigned int nr_queued[2]; /* number of queued bios */ /* * RB tree of active children throtl_grp's, which are sorted by * their ->disptime. */ |
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struct rb_root_cached pending_tree; /* RB tree of active tgs */ |
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unsigned int nr_pending; /* # queued in the tree */ unsigned long first_pending_disptime; /* disptime of the first tg */ |
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struct timer_list pending_timer; /* fires on first_pending_disptime */ |
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}; |
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enum tg_state_flags { THROTL_TG_PENDING = 1 << 0, /* on parent's pending tree */ |
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THROTL_TG_WAS_EMPTY = 1 << 1, /* bio_lists[] became non-empty */ |
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}; |
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#define rb_entry_tg(node) rb_entry((node), struct throtl_grp, rb_node) |
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enum { |
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LIMIT_LOW, |
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LIMIT_MAX, LIMIT_CNT, }; |
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struct throtl_grp { |
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/* must be the first member */ struct blkg_policy_data pd; |
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/* active throtl group service_queue member */ |
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struct rb_node rb_node; |
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/* throtl_data this group belongs to */ struct throtl_data *td; |
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/* this group's service queue */ struct throtl_service_queue service_queue; |
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/* |
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* qnode_on_self is used when bios are directly queued to this * throtl_grp so that local bios compete fairly with bios * dispatched from children. qnode_on_parent is used when bios are * dispatched from this throtl_grp into its parent and will compete * with the sibling qnode_on_parents and the parent's * qnode_on_self. */ struct throtl_qnode qnode_on_self[2]; struct throtl_qnode qnode_on_parent[2]; /* |
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* Dispatch time in jiffies. This is the estimated time when group * will unthrottle and is ready to dispatch more bio. It is used as * key to sort active groups in service tree. */ unsigned long disptime; |
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unsigned int flags; |
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/* are there any throtl rules between this group and td? */ bool has_rules[2]; |
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/* internally used bytes per second rate limits */ |
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uint64_t bps[2][LIMIT_CNT]; |
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/* user configured bps limits */ uint64_t bps_conf[2][LIMIT_CNT]; |
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/* internally used IOPS limits */ |
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unsigned int iops[2][LIMIT_CNT]; |
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/* user configured IOPS limits */ unsigned int iops_conf[2][LIMIT_CNT]; |
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/* Number of bytes dispatched in current slice */ |
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uint64_t bytes_disp[2]; |
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/* Number of bio's dispatched in current slice */ unsigned int io_disp[2]; |
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unsigned long last_low_overflow_time[2]; uint64_t last_bytes_disp[2]; unsigned int last_io_disp[2]; unsigned long last_check_time; |
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unsigned long latency_target; /* us */ |
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unsigned long latency_target_conf; /* us */ |
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/* When did we start a new slice */ unsigned long slice_start[2]; unsigned long slice_end[2]; |
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unsigned long last_finish_time; /* ns / 1024 */ unsigned long checked_last_finish_time; /* ns / 1024 */ unsigned long avg_idletime; /* ns / 1024 */ unsigned long idletime_threshold; /* us */ |
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unsigned long idletime_threshold_conf; /* us */ |
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unsigned int bio_cnt; /* total bios */ unsigned int bad_bio_cnt; /* bios exceeding latency threshold */ unsigned long bio_cnt_reset_time; |
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atomic_t io_split_cnt[2]; atomic_t last_io_split_cnt[2]; |
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struct blkg_rwstat stat_bytes; struct blkg_rwstat stat_ios; |
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}; |
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/* We measure latency for request size from <= 4k to >= 1M */ #define LATENCY_BUCKET_SIZE 9 struct latency_bucket { unsigned long total_latency; /* ns / 1024 */ int samples; }; struct avg_latency_bucket { unsigned long latency; /* ns / 1024 */ bool valid; }; |
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struct throtl_data { |
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/* service tree for active throtl groups */ |
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struct throtl_service_queue service_queue; |
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struct request_queue *queue; /* Total Number of queued bios on READ and WRITE lists */ unsigned int nr_queued[2]; |
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unsigned int throtl_slice; |
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/* Work for dispatching throttled bios */ |
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struct work_struct dispatch_work; |
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unsigned int limit_index; bool limit_valid[LIMIT_CNT]; |
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unsigned long low_upgrade_time; unsigned long low_downgrade_time; |
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unsigned int scale; |
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struct latency_bucket tmp_buckets[2][LATENCY_BUCKET_SIZE]; struct avg_latency_bucket avg_buckets[2][LATENCY_BUCKET_SIZE]; struct latency_bucket __percpu *latency_buckets[2]; |
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unsigned long last_calculate_time; |
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unsigned long filtered_latency; |
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bool track_bio_latency; |
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}; |
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static void throtl_pending_timer_fn(struct timer_list *t); |
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static inline struct throtl_grp *pd_to_tg(struct blkg_policy_data *pd) { return pd ? container_of(pd, struct throtl_grp, pd) : NULL; } |
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static inline struct throtl_grp *blkg_to_tg(struct blkcg_gq *blkg) |
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{ |
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return pd_to_tg(blkg_to_pd(blkg, &blkcg_policy_throtl)); |
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} |
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static inline struct blkcg_gq *tg_to_blkg(struct throtl_grp *tg) |
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{ |
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return pd_to_blkg(&tg->pd); |
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} |
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/** * sq_to_tg - return the throl_grp the specified service queue belongs to * @sq: the throtl_service_queue of interest * * Return the throtl_grp @sq belongs to. If @sq is the top-level one * embedded in throtl_data, %NULL is returned. */ static struct throtl_grp *sq_to_tg(struct throtl_service_queue *sq) { if (sq && sq->parent_sq) return container_of(sq, struct throtl_grp, service_queue); else return NULL; } /** * sq_to_td - return throtl_data the specified service queue belongs to * @sq: the throtl_service_queue of interest * |
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* A service_queue can be embedded in either a throtl_grp or throtl_data. |
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* Determine the associated throtl_data accordingly and return it. */ static struct throtl_data *sq_to_td(struct throtl_service_queue *sq) { struct throtl_grp *tg = sq_to_tg(sq); if (tg) return tg->td; else return container_of(sq, struct throtl_data, service_queue); } |
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/* * cgroup's limit in LIMIT_MAX is scaled if low limit is set. This scale is to * make the IO dispatch more smooth. * Scale up: linearly scale up according to lapsed time since upgrade. For * every throtl_slice, the limit scales up 1/2 .low limit till the * limit hits .max limit * Scale down: exponentially scale down if a cgroup doesn't hit its .low limit */ static uint64_t throtl_adjusted_limit(uint64_t low, struct throtl_data *td) { /* arbitrary value to avoid too big scale */ if (td->scale < 4096 && time_after_eq(jiffies, td->low_upgrade_time + td->scale * td->throtl_slice)) td->scale = (jiffies - td->low_upgrade_time) / td->throtl_slice; return low + (low >> 1) * td->scale; } |
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static uint64_t tg_bps_limit(struct throtl_grp *tg, int rw) { |
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struct blkcg_gq *blkg = tg_to_blkg(tg); |
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struct throtl_data *td; |
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uint64_t ret; if (cgroup_subsys_on_dfl(io_cgrp_subsys) && !blkg->parent) return U64_MAX; |
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td = tg->td; ret = tg->bps[rw][td->limit_index]; |
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if (ret == 0 && td->limit_index == LIMIT_LOW) { /* intermediate node or iops isn't 0 */ if (!list_empty(&blkg->blkcg->css.children) || tg->iops[rw][td->limit_index]) return U64_MAX; else return MIN_THROTL_BPS; } |
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if (td->limit_index == LIMIT_MAX && tg->bps[rw][LIMIT_LOW] && tg->bps[rw][LIMIT_LOW] != tg->bps[rw][LIMIT_MAX]) { uint64_t adjusted; adjusted = throtl_adjusted_limit(tg->bps[rw][LIMIT_LOW], td); ret = min(tg->bps[rw][LIMIT_MAX], adjusted); } |
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return ret; |
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} static unsigned int tg_iops_limit(struct throtl_grp *tg, int rw) { |
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struct blkcg_gq *blkg = tg_to_blkg(tg); |
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struct throtl_data *td; |
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unsigned int ret; if (cgroup_subsys_on_dfl(io_cgrp_subsys) && !blkg->parent) return UINT_MAX; |
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td = tg->td; ret = tg->iops[rw][td->limit_index]; |
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if (ret == 0 && tg->td->limit_index == LIMIT_LOW) { /* intermediate node or bps isn't 0 */ if (!list_empty(&blkg->blkcg->css.children) || tg->bps[rw][td->limit_index]) return UINT_MAX; else return MIN_THROTL_IOPS; } |
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if (td->limit_index == LIMIT_MAX && tg->iops[rw][LIMIT_LOW] && tg->iops[rw][LIMIT_LOW] != tg->iops[rw][LIMIT_MAX]) { uint64_t adjusted; adjusted = throtl_adjusted_limit(tg->iops[rw][LIMIT_LOW], td); if (adjusted > UINT_MAX) adjusted = UINT_MAX; ret = min_t(unsigned int, tg->iops[rw][LIMIT_MAX], adjusted); } |
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return ret; |
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} |
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#define request_bucket_index(sectors) \ clamp_t(int, order_base_2(sectors) - 3, 0, LATENCY_BUCKET_SIZE - 1) |
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/** * throtl_log - log debug message via blktrace * @sq: the service_queue being reported * @fmt: printf format string * @args: printf args * * The messages are prefixed with "throtl BLKG_NAME" if @sq belongs to a * throtl_grp; otherwise, just "throtl". |
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*/ #define throtl_log(sq, fmt, args...) do { \ struct throtl_grp *__tg = sq_to_tg((sq)); \ struct throtl_data *__td = sq_to_td((sq)); \ \ (void)__td; \ |
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if (likely(!blk_trace_note_message_enabled(__td->queue))) \ break; \ |
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if ((__tg)) { \ |
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blk_add_cgroup_trace_msg(__td->queue, \ tg_to_blkg(__tg)->blkcg, "throtl " fmt, ##args);\ |
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} else { \ blk_add_trace_msg(__td->queue, "throtl " fmt, ##args); \ } \ |
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} while (0) |
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static inline unsigned int throtl_bio_data_size(struct bio *bio) { /* assume it's one sector */ if (unlikely(bio_op(bio) == REQ_OP_DISCARD)) return 512; return bio->bi_iter.bi_size; } |
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static void throtl_qnode_init(struct throtl_qnode *qn, struct throtl_grp *tg) { INIT_LIST_HEAD(&qn->node); bio_list_init(&qn->bios); qn->tg = tg; } /** * throtl_qnode_add_bio - add a bio to a throtl_qnode and activate it * @bio: bio being added * @qn: qnode to add bio to * @queued: the service_queue->queued[] list @qn belongs to * * Add @bio to @qn and put @qn on @queued if it's not already on. * @qn->tg's reference count is bumped when @qn is activated. See the * comment on top of throtl_qnode definition for details. */ static void throtl_qnode_add_bio(struct bio *bio, struct throtl_qnode *qn, struct list_head *queued) { bio_list_add(&qn->bios, bio); if (list_empty(&qn->node)) { list_add_tail(&qn->node, queued); blkg_get(tg_to_blkg(qn->tg)); } } /** * throtl_peek_queued - peek the first bio on a qnode list * @queued: the qnode list to peek */ static struct bio *throtl_peek_queued(struct list_head *queued) { |
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struct throtl_qnode *qn; |
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struct bio *bio; if (list_empty(queued)) return NULL; |
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qn = list_first_entry(queued, struct throtl_qnode, node); |
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bio = bio_list_peek(&qn->bios); WARN_ON_ONCE(!bio); return bio; } /** * throtl_pop_queued - pop the first bio form a qnode list * @queued: the qnode list to pop a bio from * @tg_to_put: optional out argument for throtl_grp to put * * Pop the first bio from the qnode list @queued. After popping, the first * qnode is removed from @queued if empty or moved to the end of @queued so * that the popping order is round-robin. * * When the first qnode is removed, its associated throtl_grp should be put * too. If @tg_to_put is NULL, this function automatically puts it; * otherwise, *@tg_to_put is set to the throtl_grp to put and the caller is * responsible for putting it. */ static struct bio *throtl_pop_queued(struct list_head *queued, struct throtl_grp **tg_to_put) { |
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struct throtl_qnode *qn; |
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struct bio *bio; if (list_empty(queued)) return NULL; |
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qn = list_first_entry(queued, struct throtl_qnode, node); |
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bio = bio_list_pop(&qn->bios); WARN_ON_ONCE(!bio); if (bio_list_empty(&qn->bios)) { list_del_init(&qn->node); if (tg_to_put) *tg_to_put = qn->tg; else blkg_put(tg_to_blkg(qn->tg)); } else { list_move_tail(&qn->node, queued); } return bio; } |
49a2f1e3f blk-throttle: add... |
450 |
/* init a service_queue, assumes the caller zeroed it */ |
b2ce2643c blk-throttle: cle... |
451 |
static void throtl_service_queue_init(struct throtl_service_queue *sq) |
49a2f1e3f blk-throttle: add... |
452 |
{ |
c5cc2070b blk-throttle: add... |
453 454 |
INIT_LIST_HEAD(&sq->queued[0]); INIT_LIST_HEAD(&sq->queued[1]); |
9ff01255a Blk-throttle: upd... |
455 |
sq->pending_tree = RB_ROOT_CACHED; |
e99e88a9d treewide: setup_t... |
456 |
timer_setup(&sq->pending_timer, throtl_pending_timer_fn, 0); |
69df0ab03 blk-throttle: sep... |
457 |
} |
cf09a8ee1 blkcg: pass @q an... |
458 459 460 |
static struct blkg_policy_data *throtl_pd_alloc(gfp_t gfp, struct request_queue *q, struct blkcg *blkcg) |
001bea73e blkcg: replace bl... |
461 |
{ |
4fb72036f blk-throttle: rem... |
462 |
struct throtl_grp *tg; |
24bdb8ef0 blkcg: make blkcg... |
463 |
int rw; |
4fb72036f blk-throttle: rem... |
464 |
|
cf09a8ee1 blkcg: pass @q an... |
465 |
tg = kzalloc_node(sizeof(*tg), gfp, q->node); |
4fb72036f blk-throttle: rem... |
466 |
if (!tg) |
77ea73388 blkcg: move io_se... |
467 |
return NULL; |
4fb72036f blk-throttle: rem... |
468 |
|
7ca464383 blk-throtl: stop ... |
469 470 471 472 473 |
if (blkg_rwstat_init(&tg->stat_bytes, gfp)) goto err_free_tg; if (blkg_rwstat_init(&tg->stat_ios, gfp)) goto err_exit_stat_bytes; |
b2ce2643c blk-throttle: cle... |
474 475 476 477 478 479 480 481 |
throtl_service_queue_init(&tg->service_queue); for (rw = READ; rw <= WRITE; rw++) { throtl_qnode_init(&tg->qnode_on_self[rw], tg); throtl_qnode_init(&tg->qnode_on_parent[rw], tg); } RB_CLEAR_NODE(&tg->rb_node); |
9f626e372 blk-throttle: pre... |
482 483 484 485 |
tg->bps[READ][LIMIT_MAX] = U64_MAX; tg->bps[WRITE][LIMIT_MAX] = U64_MAX; tg->iops[READ][LIMIT_MAX] = UINT_MAX; tg->iops[WRITE][LIMIT_MAX] = UINT_MAX; |
cd5ab1b0f blk-throttle: add... |
486 487 488 489 490 |
tg->bps_conf[READ][LIMIT_MAX] = U64_MAX; tg->bps_conf[WRITE][LIMIT_MAX] = U64_MAX; tg->iops_conf[READ][LIMIT_MAX] = UINT_MAX; tg->iops_conf[WRITE][LIMIT_MAX] = UINT_MAX; /* LIMIT_LOW will have default value 0 */ |
b2ce2643c blk-throttle: cle... |
491 |
|
ec80991d6 blk-throttle: add... |
492 |
tg->latency_target = DFL_LATENCY_TARGET; |
5b81fc3cc blk-throttle: add... |
493 |
tg->latency_target_conf = DFL_LATENCY_TARGET; |
b4f428ef2 blk-throttle: for... |
494 495 |
tg->idletime_threshold = DFL_IDLE_THRESHOLD; tg->idletime_threshold_conf = DFL_IDLE_THRESHOLD; |
ec80991d6 blk-throttle: add... |
496 |
|
4fb72036f blk-throttle: rem... |
497 |
return &tg->pd; |
7ca464383 blk-throtl: stop ... |
498 499 500 501 502 503 |
err_exit_stat_bytes: blkg_rwstat_exit(&tg->stat_bytes); err_free_tg: kfree(tg); return NULL; |
001bea73e blkcg: replace bl... |
504 |
} |
a9520cd6f blkcg: make blkcg... |
505 |
static void throtl_pd_init(struct blkg_policy_data *pd) |
a29a171e7 blk-throttle: Do ... |
506 |
{ |
a9520cd6f blkcg: make blkcg... |
507 508 |
struct throtl_grp *tg = pd_to_tg(pd); struct blkcg_gq *blkg = tg_to_blkg(tg); |
77216b048 blk-throttle: add... |
509 |
struct throtl_data *td = blkg->q->td; |
b2ce2643c blk-throttle: cle... |
510 |
struct throtl_service_queue *sq = &tg->service_queue; |
cd1604fab blkcg: factor out... |
511 |
|
9138125be blk-throttle: imp... |
512 |
/* |
aa6ec29be cgroup: remove sa... |
513 |
* If on the default hierarchy, we switch to properly hierarchical |
9138125be blk-throttle: imp... |
514 515 516 517 518 |
* behavior where limits on a given throtl_grp are applied to the * whole subtree rather than just the group itself. e.g. If 16M * read_bps limit is set on the root group, the whole system can't * exceed 16M for the device. * |
aa6ec29be cgroup: remove sa... |
519 |
* If not on the default hierarchy, the broken flat hierarchy |
9138125be blk-throttle: imp... |
520 521 522 523 524 |
* behavior is retained where all throtl_grps are treated as if * they're all separate root groups right below throtl_data. * Limits of a group don't interact with limits of other groups * regardless of the position of the group in the hierarchy. */ |
b2ce2643c blk-throttle: cle... |
525 |
sq->parent_sq = &td->service_queue; |
9e10a130d cgroup: replace c... |
526 |
if (cgroup_subsys_on_dfl(io_cgrp_subsys) && blkg->parent) |
b2ce2643c blk-throttle: cle... |
527 |
sq->parent_sq = &blkg_to_tg(blkg->parent)->service_queue; |
77216b048 blk-throttle: add... |
528 |
tg->td = td; |
8a3d26151 blkcg: move blkio... |
529 |
} |
693e751e7 blk-throttle: imp... |
530 531 532 533 534 535 536 537 |
/* * Set has_rules[] if @tg or any of its parents have limits configured. * This doesn't require walking up to the top of the hierarchy as the * parent's has_rules[] is guaranteed to be correct. */ static void tg_update_has_rules(struct throtl_grp *tg) { struct throtl_grp *parent_tg = sq_to_tg(tg->service_queue.parent_sq); |
9f626e372 blk-throttle: pre... |
538 |
struct throtl_data *td = tg->td; |
693e751e7 blk-throttle: imp... |
539 540 541 542 |
int rw; for (rw = READ; rw <= WRITE; rw++) tg->has_rules[rw] = (parent_tg && parent_tg->has_rules[rw]) || |
9f626e372 blk-throttle: pre... |
543 544 545 |
(td->limit_valid[td->limit_index] && (tg_bps_limit(tg, rw) != U64_MAX || tg_iops_limit(tg, rw) != UINT_MAX)); |
693e751e7 blk-throttle: imp... |
546 |
} |
a9520cd6f blkcg: make blkcg... |
547 |
static void throtl_pd_online(struct blkg_policy_data *pd) |
693e751e7 blk-throttle: imp... |
548 |
{ |
aec242468 blk-throttle: det... |
549 |
struct throtl_grp *tg = pd_to_tg(pd); |
693e751e7 blk-throttle: imp... |
550 551 552 553 |
/* * We don't want new groups to escape the limits of its ancestors. * Update has_rules[] after a new group is brought online. */ |
aec242468 blk-throttle: det... |
554 |
tg_update_has_rules(tg); |
693e751e7 blk-throttle: imp... |
555 |
} |
acaf523a7 blk-throttle: don... |
556 |
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW |
cd5ab1b0f blk-throttle: add... |
557 558 559 560 561 562 563 564 565 566 567 |
static void blk_throtl_update_limit_valid(struct throtl_data *td) { struct cgroup_subsys_state *pos_css; struct blkcg_gq *blkg; bool low_valid = false; rcu_read_lock(); blkg_for_each_descendant_post(blkg, pos_css, td->queue->root_blkg) { struct throtl_grp *tg = blkg_to_tg(blkg); if (tg->bps[READ][LIMIT_LOW] || tg->bps[WRITE][LIMIT_LOW] || |
43ada7878 Block: blk-thrott... |
568 |
tg->iops[READ][LIMIT_LOW] || tg->iops[WRITE][LIMIT_LOW]) { |
cd5ab1b0f blk-throttle: add... |
569 |
low_valid = true; |
43ada7878 Block: blk-thrott... |
570 571 |
break; } |
cd5ab1b0f blk-throttle: add... |
572 573 574 575 576 |
} rcu_read_unlock(); td->limit_valid[LIMIT_LOW] = low_valid; } |
acaf523a7 blk-throttle: don... |
577 578 579 580 581 |
#else static inline void blk_throtl_update_limit_valid(struct throtl_data *td) { } #endif |
cd5ab1b0f blk-throttle: add... |
582 |
|
c79892c55 blk-throttle: add... |
583 |
static void throtl_upgrade_state(struct throtl_data *td); |
cd5ab1b0f blk-throttle: add... |
584 585 586 587 588 589 590 591 592 593 |
static void throtl_pd_offline(struct blkg_policy_data *pd) { struct throtl_grp *tg = pd_to_tg(pd); tg->bps[READ][LIMIT_LOW] = 0; tg->bps[WRITE][LIMIT_LOW] = 0; tg->iops[READ][LIMIT_LOW] = 0; tg->iops[WRITE][LIMIT_LOW] = 0; blk_throtl_update_limit_valid(tg->td); |
c79892c55 blk-throttle: add... |
594 595 |
if (!tg->td->limit_valid[tg->td->limit_index]) throtl_upgrade_state(tg->td); |
cd5ab1b0f blk-throttle: add... |
596 |
} |
001bea73e blkcg: replace bl... |
597 598 |
static void throtl_pd_free(struct blkg_policy_data *pd) { |
4fb72036f blk-throttle: rem... |
599 |
struct throtl_grp *tg = pd_to_tg(pd); |
b2ce2643c blk-throttle: cle... |
600 |
del_timer_sync(&tg->service_queue.pending_timer); |
7ca464383 blk-throtl: stop ... |
601 602 |
blkg_rwstat_exit(&tg->stat_bytes); blkg_rwstat_exit(&tg->stat_ios); |
4fb72036f blk-throttle: rem... |
603 |
kfree(tg); |
001bea73e blkcg: replace bl... |
604 |
} |
0049af73b blk-throttle: reo... |
605 606 |
static struct throtl_grp * throtl_rb_first(struct throtl_service_queue *parent_sq) |
e43473b7f blkio: Core imple... |
607 |
{ |
9ff01255a Blk-throttle: upd... |
608 |
struct rb_node *n; |
e43473b7f blkio: Core imple... |
609 |
|
9ff01255a Blk-throttle: upd... |
610 611 612 613 614 |
n = rb_first_cached(&parent_sq->pending_tree); WARN_ON_ONCE(!n); if (!n) return NULL; return rb_entry_tg(n); |
e43473b7f blkio: Core imple... |
615 |
} |
0049af73b blk-throttle: reo... |
616 617 |
static void throtl_rb_erase(struct rb_node *n, struct throtl_service_queue *parent_sq) |
e43473b7f blkio: Core imple... |
618 |
{ |
9ff01255a Blk-throttle: upd... |
619 620 |
rb_erase_cached(n, &parent_sq->pending_tree); RB_CLEAR_NODE(n); |
0049af73b blk-throttle: reo... |
621 |
--parent_sq->nr_pending; |
e43473b7f blkio: Core imple... |
622 |
} |
0049af73b blk-throttle: reo... |
623 |
static void update_min_dispatch_time(struct throtl_service_queue *parent_sq) |
e43473b7f blkio: Core imple... |
624 625 |
{ struct throtl_grp *tg; |
0049af73b blk-throttle: reo... |
626 |
tg = throtl_rb_first(parent_sq); |
e43473b7f blkio: Core imple... |
627 628 |
if (!tg) return; |
0049af73b blk-throttle: reo... |
629 |
parent_sq->first_pending_disptime = tg->disptime; |
e43473b7f blkio: Core imple... |
630 |
} |
77216b048 blk-throttle: add... |
631 |
static void tg_service_queue_add(struct throtl_grp *tg) |
e43473b7f blkio: Core imple... |
632 |
{ |
77216b048 blk-throttle: add... |
633 |
struct throtl_service_queue *parent_sq = tg->service_queue.parent_sq; |
9ff01255a Blk-throttle: upd... |
634 |
struct rb_node **node = &parent_sq->pending_tree.rb_root.rb_node; |
e43473b7f blkio: Core imple... |
635 636 637 |
struct rb_node *parent = NULL; struct throtl_grp *__tg; unsigned long key = tg->disptime; |
9ff01255a Blk-throttle: upd... |
638 |
bool leftmost = true; |
e43473b7f blkio: Core imple... |
639 640 641 642 643 644 645 646 647 |
while (*node != NULL) { parent = *node; __tg = rb_entry_tg(parent); if (time_before(key, __tg->disptime)) node = &parent->rb_left; else { node = &parent->rb_right; |
9ff01255a Blk-throttle: upd... |
648 |
leftmost = false; |
e43473b7f blkio: Core imple... |
649 650 |
} } |
e43473b7f blkio: Core imple... |
651 |
rb_link_node(&tg->rb_node, parent, node); |
9ff01255a Blk-throttle: upd... |
652 653 |
rb_insert_color_cached(&tg->rb_node, &parent_sq->pending_tree, leftmost); |
e43473b7f blkio: Core imple... |
654 |
} |
77216b048 blk-throttle: add... |
655 |
static void throtl_enqueue_tg(struct throtl_grp *tg) |
e43473b7f blkio: Core imple... |
656 |
{ |
29379674b blk-throttle: Ope... |
657 658 659 660 661 |
if (!(tg->flags & THROTL_TG_PENDING)) { tg_service_queue_add(tg); tg->flags |= THROTL_TG_PENDING; tg->service_queue.parent_sq->nr_pending++; } |
e43473b7f blkio: Core imple... |
662 |
} |
77216b048 blk-throttle: add... |
663 |
static void throtl_dequeue_tg(struct throtl_grp *tg) |
e43473b7f blkio: Core imple... |
664 |
{ |
29379674b blk-throttle: Ope... |
665 666 667 668 |
if (tg->flags & THROTL_TG_PENDING) { throtl_rb_erase(&tg->rb_node, tg->service_queue.parent_sq); tg->flags &= ~THROTL_TG_PENDING; } |
e43473b7f blkio: Core imple... |
669 |
} |
a9131a27e blk-throttle: rel... |
670 |
/* Call with queue lock held */ |
69df0ab03 blk-throttle: sep... |
671 672 |
static void throtl_schedule_pending_timer(struct throtl_service_queue *sq, unsigned long expires) |
a9131a27e blk-throttle: rel... |
673 |
{ |
a41b816c1 blk-throttle: fix... |
674 |
unsigned long max_expire = jiffies + 8 * sq_to_td(sq)->throtl_slice; |
06cceedcc blk-throttle: mak... |
675 676 677 678 679 680 681 682 683 684 |
/* * Since we are adjusting the throttle limit dynamically, the sleep * time calculated according to previous limit might be invalid. It's * possible the cgroup sleep time is very long and no other cgroups * have IO running so notify the limit changes. Make sure the cgroup * doesn't sleep too long to avoid the missed notification. */ if (time_after(expires, max_expire)) expires = max_expire; |
69df0ab03 blk-throttle: sep... |
685 686 687 |
mod_timer(&sq->pending_timer, expires); throtl_log(sq, "schedule timer. delay=%lu jiffies=%lu", expires - jiffies, jiffies); |
a9131a27e blk-throttle: rel... |
688 |
} |
7f52f98c2 blk-throttle: imp... |
689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 |
/** * throtl_schedule_next_dispatch - schedule the next dispatch cycle * @sq: the service_queue to schedule dispatch for * @force: force scheduling * * Arm @sq->pending_timer so that the next dispatch cycle starts on the * dispatch time of the first pending child. Returns %true if either timer * is armed or there's no pending child left. %false if the current * dispatch window is still open and the caller should continue * dispatching. * * If @force is %true, the dispatch timer is always scheduled and this * function is guaranteed to return %true. This is to be used when the * caller can't dispatch itself and needs to invoke pending_timer * unconditionally. Note that forced scheduling is likely to induce short * delay before dispatch starts even if @sq->first_pending_disptime is not * in the future and thus shouldn't be used in hot paths. */ static bool throtl_schedule_next_dispatch(struct throtl_service_queue *sq, bool force) |
e43473b7f blkio: Core imple... |
709 |
{ |
6a525600f blk-throttle: rem... |
710 |
/* any pending children left? */ |
c9e0332e8 blk-throttle: ren... |
711 |
if (!sq->nr_pending) |
7f52f98c2 blk-throttle: imp... |
712 |
return true; |
e43473b7f blkio: Core imple... |
713 |
|
c9e0332e8 blk-throttle: ren... |
714 |
update_min_dispatch_time(sq); |
e43473b7f blkio: Core imple... |
715 |
|
69df0ab03 blk-throttle: sep... |
716 |
/* is the next dispatch time in the future? */ |
7f52f98c2 blk-throttle: imp... |
717 |
if (force || time_after(sq->first_pending_disptime, jiffies)) { |
69df0ab03 blk-throttle: sep... |
718 |
throtl_schedule_pending_timer(sq, sq->first_pending_disptime); |
7f52f98c2 blk-throttle: imp... |
719 |
return true; |
69df0ab03 blk-throttle: sep... |
720 |
} |
7f52f98c2 blk-throttle: imp... |
721 722 |
/* tell the caller to continue dispatching */ return false; |
e43473b7f blkio: Core imple... |
723 |
} |
32ee5bc47 blk-throttle: Acc... |
724 725 726 727 728 |
static inline void throtl_start_new_slice_with_credit(struct throtl_grp *tg, bool rw, unsigned long start) { tg->bytes_disp[rw] = 0; tg->io_disp[rw] = 0; |
4f1e9630a blk-throtl: optim... |
729 |
atomic_set(&tg->io_split_cnt[rw], 0); |
32ee5bc47 blk-throttle: Acc... |
730 731 732 733 734 735 736 737 |
/* * Previous slice has expired. We must have trimmed it after last * bio dispatch. That means since start of last slice, we never used * that bandwidth. Do try to make use of that bandwidth while giving * credit. */ if (time_after_eq(start, tg->slice_start[rw])) tg->slice_start[rw] = start; |
297e3d854 blk-throttle: mak... |
738 |
tg->slice_end[rw] = jiffies + tg->td->throtl_slice; |
32ee5bc47 blk-throttle: Acc... |
739 740 741 742 743 |
throtl_log(&tg->service_queue, "[%c] new slice with credit start=%lu end=%lu jiffies=%lu", rw == READ ? 'R' : 'W', tg->slice_start[rw], tg->slice_end[rw], jiffies); } |
0f3457f60 blk-throttle: add... |
744 |
static inline void throtl_start_new_slice(struct throtl_grp *tg, bool rw) |
e43473b7f blkio: Core imple... |
745 746 |
{ tg->bytes_disp[rw] = 0; |
8e89d13f4 blkio: Implementa... |
747 |
tg->io_disp[rw] = 0; |
e43473b7f blkio: Core imple... |
748 |
tg->slice_start[rw] = jiffies; |
297e3d854 blk-throttle: mak... |
749 |
tg->slice_end[rw] = jiffies + tg->td->throtl_slice; |
4f1e9630a blk-throtl: optim... |
750 751 |
atomic_set(&tg->io_split_cnt[rw], 0); |
fda6f272c blk-throttle: imp... |
752 753 754 755 |
throtl_log(&tg->service_queue, "[%c] new slice start=%lu end=%lu jiffies=%lu", rw == READ ? 'R' : 'W', tg->slice_start[rw], tg->slice_end[rw], jiffies); |
e43473b7f blkio: Core imple... |
756 |
} |
0f3457f60 blk-throttle: add... |
757 758 |
static inline void throtl_set_slice_end(struct throtl_grp *tg, bool rw, unsigned long jiffy_end) |
d1ae8ffdf blk-throttle: Tri... |
759 |
{ |
297e3d854 blk-throttle: mak... |
760 |
tg->slice_end[rw] = roundup(jiffy_end, tg->td->throtl_slice); |
d1ae8ffdf blk-throttle: Tri... |
761 |
} |
0f3457f60 blk-throttle: add... |
762 763 |
static inline void throtl_extend_slice(struct throtl_grp *tg, bool rw, unsigned long jiffy_end) |
e43473b7f blkio: Core imple... |
764 |
{ |
1da30f952 blk-throttle: Re-... |
765 |
throtl_set_slice_end(tg, rw, jiffy_end); |
fda6f272c blk-throttle: imp... |
766 767 768 769 |
throtl_log(&tg->service_queue, "[%c] extend slice start=%lu end=%lu jiffies=%lu", rw == READ ? 'R' : 'W', tg->slice_start[rw], tg->slice_end[rw], jiffies); |
e43473b7f blkio: Core imple... |
770 771 772 |
} /* Determine if previously allocated or extended slice is complete or not */ |
0f3457f60 blk-throttle: add... |
773 |
static bool throtl_slice_used(struct throtl_grp *tg, bool rw) |
e43473b7f blkio: Core imple... |
774 775 |
{ if (time_in_range(jiffies, tg->slice_start[rw], tg->slice_end[rw])) |
5cf8c2277 block/blk-throttl... |
776 |
return false; |
e43473b7f blkio: Core imple... |
777 |
|
0b6bad7d6 blk-throttle: ret... |
778 |
return true; |
e43473b7f blkio: Core imple... |
779 780 781 |
} /* Trim the used slices and adjust slice start accordingly */ |
0f3457f60 blk-throttle: add... |
782 |
static inline void throtl_trim_slice(struct throtl_grp *tg, bool rw) |
e43473b7f blkio: Core imple... |
783 |
{ |
3aad5d3ee blkio-throttle: F... |
784 785 |
unsigned long nr_slices, time_elapsed, io_trim; u64 bytes_trim, tmp; |
e43473b7f blkio: Core imple... |
786 787 788 789 790 791 792 793 |
BUG_ON(time_before(tg->slice_end[rw], tg->slice_start[rw])); /* * If bps are unlimited (-1), then time slice don't get * renewed. Don't try to trim the slice if slice is used. A new * slice will start when appropriate. */ |
0f3457f60 blk-throttle: add... |
794 |
if (throtl_slice_used(tg, rw)) |
e43473b7f blkio: Core imple... |
795 |
return; |
d1ae8ffdf blk-throttle: Tri... |
796 797 798 |
/* * A bio has been dispatched. Also adjust slice_end. It might happen * that initially cgroup limit was very low resulting in high |
b53b072c4 blk-throttle: Fix... |
799 |
* slice_end, but later limit was bumped up and bio was dispatched |
d1ae8ffdf blk-throttle: Tri... |
800 801 802 |
* sooner, then we need to reduce slice_end. A high bogus slice_end * is bad because it does not allow new slice to start. */ |
297e3d854 blk-throttle: mak... |
803 |
throtl_set_slice_end(tg, rw, jiffies + tg->td->throtl_slice); |
d1ae8ffdf blk-throttle: Tri... |
804 |
|
e43473b7f blkio: Core imple... |
805 |
time_elapsed = jiffies - tg->slice_start[rw]; |
297e3d854 blk-throttle: mak... |
806 |
nr_slices = time_elapsed / tg->td->throtl_slice; |
e43473b7f blkio: Core imple... |
807 808 809 |
if (!nr_slices) return; |
297e3d854 blk-throttle: mak... |
810 |
tmp = tg_bps_limit(tg, rw) * tg->td->throtl_slice * nr_slices; |
3aad5d3ee blkio-throttle: F... |
811 812 |
do_div(tmp, HZ); bytes_trim = tmp; |
e43473b7f blkio: Core imple... |
813 |
|
297e3d854 blk-throttle: mak... |
814 815 |
io_trim = (tg_iops_limit(tg, rw) * tg->td->throtl_slice * nr_slices) / HZ; |
e43473b7f blkio: Core imple... |
816 |
|
8e89d13f4 blkio: Implementa... |
817 |
if (!bytes_trim && !io_trim) |
e43473b7f blkio: Core imple... |
818 819 820 821 822 823 |
return; if (tg->bytes_disp[rw] >= bytes_trim) tg->bytes_disp[rw] -= bytes_trim; else tg->bytes_disp[rw] = 0; |
8e89d13f4 blkio: Implementa... |
824 825 826 827 |
if (tg->io_disp[rw] >= io_trim) tg->io_disp[rw] -= io_trim; else tg->io_disp[rw] = 0; |
297e3d854 blk-throttle: mak... |
828 |
tg->slice_start[rw] += nr_slices * tg->td->throtl_slice; |
e43473b7f blkio: Core imple... |
829 |
|
fda6f272c blk-throttle: imp... |
830 831 832 833 |
throtl_log(&tg->service_queue, "[%c] trim slice nr=%lu bytes=%llu io=%lu start=%lu end=%lu jiffies=%lu", rw == READ ? 'R' : 'W', nr_slices, bytes_trim, io_trim, tg->slice_start[rw], tg->slice_end[rw], jiffies); |
e43473b7f blkio: Core imple... |
834 |
} |
0f3457f60 blk-throttle: add... |
835 |
static bool tg_with_in_iops_limit(struct throtl_grp *tg, struct bio *bio, |
4599ea49d blk-throttle: Avo... |
836 |
u32 iops_limit, unsigned long *wait) |
e43473b7f blkio: Core imple... |
837 838 |
{ bool rw = bio_data_dir(bio); |
8e89d13f4 blkio: Implementa... |
839 |
unsigned int io_allowed; |
e43473b7f blkio: Core imple... |
840 |
unsigned long jiffy_elapsed, jiffy_wait, jiffy_elapsed_rnd; |
c49c06e49 blkio-throttle: F... |
841 |
u64 tmp; |
e43473b7f blkio: Core imple... |
842 |
|
87fbeb881 blk-throttle: Avo... |
843 844 845 846 847 |
if (iops_limit == UINT_MAX) { if (wait) *wait = 0; return true; } |
3a10f999f blk-throttle: fix... |
848 |
jiffy_elapsed = jiffies - tg->slice_start[rw]; |
e43473b7f blkio: Core imple... |
849 |
|
3a10f999f blk-throttle: fix... |
850 851 |
/* Round up to the next throttle slice, wait time must be nonzero */ jiffy_elapsed_rnd = roundup(jiffy_elapsed + 1, tg->td->throtl_slice); |
8e89d13f4 blkio: Implementa... |
852 |
|
c49c06e49 blkio-throttle: F... |
853 854 855 856 857 858 |
/* * jiffy_elapsed_rnd should not be a big value as minimum iops can be * 1 then at max jiffy elapsed should be equivalent of 1 second as we * will allow dispatch after 1 second and after that slice should * have been trimmed. */ |
4599ea49d blk-throttle: Avo... |
859 |
tmp = (u64)iops_limit * jiffy_elapsed_rnd; |
c49c06e49 blkio-throttle: F... |
860 861 862 863 864 865 |
do_div(tmp, HZ); if (tmp > UINT_MAX) io_allowed = UINT_MAX; else io_allowed = tmp; |
8e89d13f4 blkio: Implementa... |
866 867 |
if (tg->io_disp[rw] + 1 <= io_allowed) { |
e43473b7f blkio: Core imple... |
868 869 |
if (wait) *wait = 0; |
5cf8c2277 block/blk-throttl... |
870 |
return true; |
e43473b7f blkio: Core imple... |
871 |
} |
8e89d13f4 blkio: Implementa... |
872 |
/* Calc approx time to dispatch */ |
991f61fe7 Blk-throttle: red... |
873 |
jiffy_wait = jiffy_elapsed_rnd - jiffy_elapsed; |
8e89d13f4 blkio: Implementa... |
874 875 876 |
if (wait) *wait = jiffy_wait; |
0b6bad7d6 blk-throttle: ret... |
877 |
return false; |
8e89d13f4 blkio: Implementa... |
878 |
} |
0f3457f60 blk-throttle: add... |
879 |
static bool tg_with_in_bps_limit(struct throtl_grp *tg, struct bio *bio, |
4599ea49d blk-throttle: Avo... |
880 |
u64 bps_limit, unsigned long *wait) |
8e89d13f4 blkio: Implementa... |
881 882 |
{ bool rw = bio_data_dir(bio); |
3aad5d3ee blkio-throttle: F... |
883 |
u64 bytes_allowed, extra_bytes, tmp; |
8e89d13f4 blkio: Implementa... |
884 |
unsigned long jiffy_elapsed, jiffy_wait, jiffy_elapsed_rnd; |
ea0ea2bc6 blk-throttle: cap... |
885 |
unsigned int bio_size = throtl_bio_data_size(bio); |
e43473b7f blkio: Core imple... |
886 |
|
87fbeb881 blk-throttle: Avo... |
887 888 889 890 891 |
if (bps_limit == U64_MAX) { if (wait) *wait = 0; return true; } |
e43473b7f blkio: Core imple... |
892 893 894 895 |
jiffy_elapsed = jiffy_elapsed_rnd = jiffies - tg->slice_start[rw]; /* Slice has just started. Consider one slice interval */ if (!jiffy_elapsed) |
297e3d854 blk-throttle: mak... |
896 |
jiffy_elapsed_rnd = tg->td->throtl_slice; |
e43473b7f blkio: Core imple... |
897 |
|
297e3d854 blk-throttle: mak... |
898 |
jiffy_elapsed_rnd = roundup(jiffy_elapsed_rnd, tg->td->throtl_slice); |
e43473b7f blkio: Core imple... |
899 |
|
4599ea49d blk-throttle: Avo... |
900 |
tmp = bps_limit * jiffy_elapsed_rnd; |
5e901a2b9 blkio-throttle: T... |
901 |
do_div(tmp, HZ); |
3aad5d3ee blkio-throttle: F... |
902 |
bytes_allowed = tmp; |
e43473b7f blkio: Core imple... |
903 |
|
ea0ea2bc6 blk-throttle: cap... |
904 |
if (tg->bytes_disp[rw] + bio_size <= bytes_allowed) { |
e43473b7f blkio: Core imple... |
905 906 |
if (wait) *wait = 0; |
5cf8c2277 block/blk-throttl... |
907 |
return true; |
e43473b7f blkio: Core imple... |
908 909 910 |
} /* Calc approx time to dispatch */ |
ea0ea2bc6 blk-throttle: cap... |
911 |
extra_bytes = tg->bytes_disp[rw] + bio_size - bytes_allowed; |
4599ea49d blk-throttle: Avo... |
912 |
jiffy_wait = div64_u64(extra_bytes * HZ, bps_limit); |
e43473b7f blkio: Core imple... |
913 914 915 916 917 918 919 920 921 |
if (!jiffy_wait) jiffy_wait = 1; /* * This wait time is without taking into consideration the rounding * up we did. Add that time also. */ jiffy_wait = jiffy_wait + (jiffy_elapsed_rnd - jiffy_elapsed); |
e43473b7f blkio: Core imple... |
922 923 |
if (wait) *wait = jiffy_wait; |
0b6bad7d6 blk-throttle: ret... |
924 |
return false; |
8e89d13f4 blkio: Implementa... |
925 926 927 928 929 930 |
} /* * Returns whether one can dispatch a bio or not. Also returns approx number * of jiffies to wait before this bio is with-in IO rate and can be dispatched */ |
0f3457f60 blk-throttle: add... |
931 932 |
static bool tg_may_dispatch(struct throtl_grp *tg, struct bio *bio, unsigned long *wait) |
8e89d13f4 blkio: Implementa... |
933 934 935 |
{ bool rw = bio_data_dir(bio); unsigned long bps_wait = 0, iops_wait = 0, max_wait = 0; |
4599ea49d blk-throttle: Avo... |
936 937 |
u64 bps_limit = tg_bps_limit(tg, rw); u32 iops_limit = tg_iops_limit(tg, rw); |
8e89d13f4 blkio: Implementa... |
938 939 940 941 942 943 944 |
/* * Currently whole state machine of group depends on first bio * queued in the group bio list. So one should not be calling * this function with a different bio if there are other bios * queued. */ |
73f0d49a9 blk-throttle: mov... |
945 |
BUG_ON(tg->service_queue.nr_queued[rw] && |
c5cc2070b blk-throttle: add... |
946 |
bio != throtl_peek_queued(&tg->service_queue.queued[rw])); |
e43473b7f blkio: Core imple... |
947 |
|
8e89d13f4 blkio: Implementa... |
948 |
/* If tg->bps = -1, then BW is unlimited */ |
4599ea49d blk-throttle: Avo... |
949 |
if (bps_limit == U64_MAX && iops_limit == UINT_MAX) { |
8e89d13f4 blkio: Implementa... |
950 951 |
if (wait) *wait = 0; |
5cf8c2277 block/blk-throttl... |
952 |
return true; |
8e89d13f4 blkio: Implementa... |
953 954 955 956 957 |
} /* * If previous slice expired, start a new one otherwise renew/extend * existing slice to make sure it is at least throtl_slice interval |
164c80ed8 blk-throttle: Ext... |
958 959 960 |
* long since now. New slice is started only for empty throttle group. * If there is queued bio, that means there should be an active * slice and it should be extended instead. |
8e89d13f4 blkio: Implementa... |
961 |
*/ |
164c80ed8 blk-throttle: Ext... |
962 |
if (throtl_slice_used(tg, rw) && !(tg->service_queue.nr_queued[rw])) |
0f3457f60 blk-throttle: add... |
963 |
throtl_start_new_slice(tg, rw); |
8e89d13f4 blkio: Implementa... |
964 |
else { |
297e3d854 blk-throttle: mak... |
965 966 967 968 |
if (time_before(tg->slice_end[rw], jiffies + tg->td->throtl_slice)) throtl_extend_slice(tg, rw, jiffies + tg->td->throtl_slice); |
8e89d13f4 blkio: Implementa... |
969 |
} |
4f1e9630a blk-throtl: optim... |
970 971 |
if (iops_limit != UINT_MAX) tg->io_disp[rw] += atomic_xchg(&tg->io_split_cnt[rw], 0); |
4599ea49d blk-throttle: Avo... |
972 973 |
if (tg_with_in_bps_limit(tg, bio, bps_limit, &bps_wait) && tg_with_in_iops_limit(tg, bio, iops_limit, &iops_wait)) { |
8e89d13f4 blkio: Implementa... |
974 975 |
if (wait) *wait = 0; |
0b6bad7d6 blk-throttle: ret... |
976 |
return true; |
8e89d13f4 blkio: Implementa... |
977 978 979 980 981 982 983 984 |
} max_wait = max(bps_wait, iops_wait); if (wait) *wait = max_wait; if (time_before(tg->slice_end[rw], jiffies + max_wait)) |
0f3457f60 blk-throttle: add... |
985 |
throtl_extend_slice(tg, rw, jiffies + max_wait); |
e43473b7f blkio: Core imple... |
986 |
|
0b6bad7d6 blk-throttle: ret... |
987 |
return false; |
e43473b7f blkio: Core imple... |
988 989 990 991 992 |
} static void throtl_charge_bio(struct throtl_grp *tg, struct bio *bio) { bool rw = bio_data_dir(bio); |
ea0ea2bc6 blk-throttle: cap... |
993 |
unsigned int bio_size = throtl_bio_data_size(bio); |
e43473b7f blkio: Core imple... |
994 995 |
/* Charge the bio to the group */ |
ea0ea2bc6 blk-throttle: cap... |
996 |
tg->bytes_disp[rw] += bio_size; |
8e89d13f4 blkio: Implementa... |
997 |
tg->io_disp[rw]++; |
ea0ea2bc6 blk-throttle: cap... |
998 |
tg->last_bytes_disp[rw] += bio_size; |
3f0abd806 blk-throttle: add... |
999 |
tg->last_io_disp[rw]++; |
e43473b7f blkio: Core imple... |
1000 |
|
2a0f61e6e blk-throttle: set... |
1001 |
/* |
8d2bbd4c8 block: replace RE... |
1002 |
* BIO_THROTTLED is used to prevent the same bio to be throttled |
2a0f61e6e blk-throttle: set... |
1003 1004 1005 |
* more than once as a throttled bio will go through blk-throtl the * second time when it eventually gets issued. Set it when a bio * is being charged to a tg. |
2a0f61e6e blk-throttle: set... |
1006 |
*/ |
8d2bbd4c8 block: replace RE... |
1007 1008 |
if (!bio_flagged(bio, BIO_THROTTLED)) bio_set_flag(bio, BIO_THROTTLED); |
e43473b7f blkio: Core imple... |
1009 |
} |
c5cc2070b blk-throttle: add... |
1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 |
/** * throtl_add_bio_tg - add a bio to the specified throtl_grp * @bio: bio to add * @qn: qnode to use * @tg: the target throtl_grp * * Add @bio to @tg's service_queue using @qn. If @qn is not specified, * tg->qnode_on_self[] is used. */ static void throtl_add_bio_tg(struct bio *bio, struct throtl_qnode *qn, struct throtl_grp *tg) |
e43473b7f blkio: Core imple... |
1021 |
{ |
73f0d49a9 blk-throttle: mov... |
1022 |
struct throtl_service_queue *sq = &tg->service_queue; |
e43473b7f blkio: Core imple... |
1023 |
bool rw = bio_data_dir(bio); |
c5cc2070b blk-throttle: add... |
1024 1025 |
if (!qn) qn = &tg->qnode_on_self[rw]; |
0e9f4164b blk-throttle: gen... |
1026 1027 1028 1029 |
/* * If @tg doesn't currently have any bios queued in the same * direction, queueing @bio can change when @tg should be * dispatched. Mark that @tg was empty. This is automatically |
b53b072c4 blk-throttle: Fix... |
1030 |
* cleared on the next tg_update_disptime(). |
0e9f4164b blk-throttle: gen... |
1031 1032 1033 |
*/ if (!sq->nr_queued[rw]) tg->flags |= THROTL_TG_WAS_EMPTY; |
c5cc2070b blk-throttle: add... |
1034 |
throtl_qnode_add_bio(bio, qn, &sq->queued[rw]); |
73f0d49a9 blk-throttle: mov... |
1035 |
sq->nr_queued[rw]++; |
77216b048 blk-throttle: add... |
1036 |
throtl_enqueue_tg(tg); |
e43473b7f blkio: Core imple... |
1037 |
} |
77216b048 blk-throttle: add... |
1038 |
static void tg_update_disptime(struct throtl_grp *tg) |
e43473b7f blkio: Core imple... |
1039 |
{ |
73f0d49a9 blk-throttle: mov... |
1040 |
struct throtl_service_queue *sq = &tg->service_queue; |
e43473b7f blkio: Core imple... |
1041 1042 |
unsigned long read_wait = -1, write_wait = -1, min_wait = -1, disptime; struct bio *bio; |
d609af3a1 blk-throttle: Adj... |
1043 1044 |
bio = throtl_peek_queued(&sq->queued[READ]); if (bio) |
0f3457f60 blk-throttle: add... |
1045 |
tg_may_dispatch(tg, bio, &read_wait); |
e43473b7f blkio: Core imple... |
1046 |
|
d609af3a1 blk-throttle: Adj... |
1047 1048 |
bio = throtl_peek_queued(&sq->queued[WRITE]); if (bio) |
0f3457f60 blk-throttle: add... |
1049 |
tg_may_dispatch(tg, bio, &write_wait); |
e43473b7f blkio: Core imple... |
1050 1051 1052 |
min_wait = min(read_wait, write_wait); disptime = jiffies + min_wait; |
e43473b7f blkio: Core imple... |
1053 |
/* Update dispatch time */ |
77216b048 blk-throttle: add... |
1054 |
throtl_dequeue_tg(tg); |
e43473b7f blkio: Core imple... |
1055 |
tg->disptime = disptime; |
77216b048 blk-throttle: add... |
1056 |
throtl_enqueue_tg(tg); |
0e9f4164b blk-throttle: gen... |
1057 1058 1059 |
/* see throtl_add_bio_tg() */ tg->flags &= ~THROTL_TG_WAS_EMPTY; |
e43473b7f blkio: Core imple... |
1060 |
} |
32ee5bc47 blk-throttle: Acc... |
1061 1062 1063 1064 1065 1066 1067 1068 1069 |
static void start_parent_slice_with_credit(struct throtl_grp *child_tg, struct throtl_grp *parent_tg, bool rw) { if (throtl_slice_used(parent_tg, rw)) { throtl_start_new_slice_with_credit(parent_tg, rw, child_tg->slice_start[rw]); } } |
77216b048 blk-throttle: add... |
1070 |
static void tg_dispatch_one_bio(struct throtl_grp *tg, bool rw) |
e43473b7f blkio: Core imple... |
1071 |
{ |
73f0d49a9 blk-throttle: mov... |
1072 |
struct throtl_service_queue *sq = &tg->service_queue; |
6bc9c2b46 blk-throttle: mak... |
1073 1074 |
struct throtl_service_queue *parent_sq = sq->parent_sq; struct throtl_grp *parent_tg = sq_to_tg(parent_sq); |
c5cc2070b blk-throttle: add... |
1075 |
struct throtl_grp *tg_to_put = NULL; |
e43473b7f blkio: Core imple... |
1076 |
struct bio *bio; |
c5cc2070b blk-throttle: add... |
1077 1078 1079 1080 1081 1082 1083 |
/* * @bio is being transferred from @tg to @parent_sq. Popping a bio * from @tg may put its reference and @parent_sq might end up * getting released prematurely. Remember the tg to put and put it * after @bio is transferred to @parent_sq. */ bio = throtl_pop_queued(&sq->queued[rw], &tg_to_put); |
73f0d49a9 blk-throttle: mov... |
1084 |
sq->nr_queued[rw]--; |
e43473b7f blkio: Core imple... |
1085 1086 |
throtl_charge_bio(tg, bio); |
6bc9c2b46 blk-throttle: mak... |
1087 1088 1089 1090 1091 1092 1093 1094 1095 |
/* * If our parent is another tg, we just need to transfer @bio to * the parent using throtl_add_bio_tg(). If our parent is * @td->service_queue, @bio is ready to be issued. Put it on its * bio_lists[] and decrease total number queued. The caller is * responsible for issuing these bios. */ if (parent_tg) { |
c5cc2070b blk-throttle: add... |
1096 |
throtl_add_bio_tg(bio, &tg->qnode_on_parent[rw], parent_tg); |
32ee5bc47 blk-throttle: Acc... |
1097 |
start_parent_slice_with_credit(tg, parent_tg, rw); |
6bc9c2b46 blk-throttle: mak... |
1098 |
} else { |
c5cc2070b blk-throttle: add... |
1099 1100 |
throtl_qnode_add_bio(bio, &tg->qnode_on_parent[rw], &parent_sq->queued[rw]); |
6bc9c2b46 blk-throttle: mak... |
1101 1102 1103 |
BUG_ON(tg->td->nr_queued[rw] <= 0); tg->td->nr_queued[rw]--; } |
e43473b7f blkio: Core imple... |
1104 |
|
0f3457f60 blk-throttle: add... |
1105 |
throtl_trim_slice(tg, rw); |
6bc9c2b46 blk-throttle: mak... |
1106 |
|
c5cc2070b blk-throttle: add... |
1107 1108 |
if (tg_to_put) blkg_put(tg_to_blkg(tg_to_put)); |
e43473b7f blkio: Core imple... |
1109 |
} |
77216b048 blk-throttle: add... |
1110 |
static int throtl_dispatch_tg(struct throtl_grp *tg) |
e43473b7f blkio: Core imple... |
1111 |
{ |
73f0d49a9 blk-throttle: mov... |
1112 |
struct throtl_service_queue *sq = &tg->service_queue; |
e43473b7f blkio: Core imple... |
1113 |
unsigned int nr_reads = 0, nr_writes = 0; |
e675df2ad blk-throttle: Def... |
1114 1115 |
unsigned int max_nr_reads = THROTL_GRP_QUANTUM * 3 / 4; unsigned int max_nr_writes = THROTL_GRP_QUANTUM - max_nr_reads; |
e43473b7f blkio: Core imple... |
1116 1117 1118 |
struct bio *bio; /* Try to dispatch 75% READS and 25% WRITES */ |
c5cc2070b blk-throttle: add... |
1119 |
while ((bio = throtl_peek_queued(&sq->queued[READ])) && |
0f3457f60 blk-throttle: add... |
1120 |
tg_may_dispatch(tg, bio, NULL)) { |
e43473b7f blkio: Core imple... |
1121 |
|
77216b048 blk-throttle: add... |
1122 |
tg_dispatch_one_bio(tg, bio_data_dir(bio)); |
e43473b7f blkio: Core imple... |
1123 1124 1125 1126 1127 |
nr_reads++; if (nr_reads >= max_nr_reads) break; } |
c5cc2070b blk-throttle: add... |
1128 |
while ((bio = throtl_peek_queued(&sq->queued[WRITE])) && |
0f3457f60 blk-throttle: add... |
1129 |
tg_may_dispatch(tg, bio, NULL)) { |
e43473b7f blkio: Core imple... |
1130 |
|
77216b048 blk-throttle: add... |
1131 |
tg_dispatch_one_bio(tg, bio_data_dir(bio)); |
e43473b7f blkio: Core imple... |
1132 1133 1134 1135 1136 1137 1138 1139 |
nr_writes++; if (nr_writes >= max_nr_writes) break; } return nr_reads + nr_writes; } |
651930bc1 blk-throttle: dis... |
1140 |
static int throtl_select_dispatch(struct throtl_service_queue *parent_sq) |
e43473b7f blkio: Core imple... |
1141 1142 |
{ unsigned int nr_disp = 0; |
e43473b7f blkio: Core imple... |
1143 1144 |
while (1) { |
2397611ac blk-throttle: Mov... |
1145 |
struct throtl_grp *tg; |
2ab74cd29 blk-throttle: fix... |
1146 |
struct throtl_service_queue *sq; |
e43473b7f blkio: Core imple... |
1147 |
|
2397611ac blk-throttle: Mov... |
1148 1149 1150 1151 |
if (!parent_sq->nr_pending) break; tg = throtl_rb_first(parent_sq); |
e43473b7f blkio: Core imple... |
1152 1153 1154 1155 1156 |
if (!tg) break; if (time_before(jiffies, tg->disptime)) break; |
77216b048 blk-throttle: add... |
1157 |
throtl_dequeue_tg(tg); |
e43473b7f blkio: Core imple... |
1158 |
|
77216b048 blk-throttle: add... |
1159 |
nr_disp += throtl_dispatch_tg(tg); |
e43473b7f blkio: Core imple... |
1160 |
|
2ab74cd29 blk-throttle: fix... |
1161 |
sq = &tg->service_queue; |
73f0d49a9 blk-throttle: mov... |
1162 |
if (sq->nr_queued[0] || sq->nr_queued[1]) |
77216b048 blk-throttle: add... |
1163 |
tg_update_disptime(tg); |
e43473b7f blkio: Core imple... |
1164 |
|
e675df2ad blk-throttle: Def... |
1165 |
if (nr_disp >= THROTL_QUANTUM) |
e43473b7f blkio: Core imple... |
1166 1167 1168 1169 1170 |
break; } return nr_disp; } |
c79892c55 blk-throttle: add... |
1171 1172 |
static bool throtl_can_upgrade(struct throtl_data *td, struct throtl_grp *this_tg); |
6e1a5704c blk-throttle: dis... |
1173 1174 |
/** * throtl_pending_timer_fn - timer function for service_queue->pending_timer |
216382dcc block: Fix throtl... |
1175 |
* @t: the pending_timer member of the throtl_service_queue being serviced |
6e1a5704c blk-throttle: dis... |
1176 1177 1178 1179 |
* * This timer is armed when a child throtl_grp with active bio's become * pending and queued on the service_queue's pending_tree and expires when * the first child throtl_grp should be dispatched. This function |
2e48a530a blk-throttle: mak... |
1180 1181 1182 1183 1184 1185 1186 |
* dispatches bio's from the children throtl_grps to the parent * service_queue. * * If the parent's parent is another throtl_grp, dispatching is propagated * by either arming its pending_timer or repeating dispatch directly. If * the top-level service_tree is reached, throtl_data->dispatch_work is * kicked so that the ready bio's are issued. |
6e1a5704c blk-throttle: dis... |
1187 |
*/ |
e99e88a9d treewide: setup_t... |
1188 |
static void throtl_pending_timer_fn(struct timer_list *t) |
69df0ab03 blk-throttle: sep... |
1189 |
{ |
e99e88a9d treewide: setup_t... |
1190 |
struct throtl_service_queue *sq = from_timer(sq, t, pending_timer); |
2e48a530a blk-throttle: mak... |
1191 |
struct throtl_grp *tg = sq_to_tg(sq); |
69df0ab03 blk-throttle: sep... |
1192 |
struct throtl_data *td = sq_to_td(sq); |
cb76199c3 blk-throttle: col... |
1193 |
struct request_queue *q = td->queue; |
2e48a530a blk-throttle: mak... |
1194 1195 |
struct throtl_service_queue *parent_sq; bool dispatched; |
6e1a5704c blk-throttle: dis... |
1196 |
int ret; |
e43473b7f blkio: Core imple... |
1197 |
|
0d945c1f9 block: remove the... |
1198 |
spin_lock_irq(&q->queue_lock); |
c79892c55 blk-throttle: add... |
1199 1200 |
if (throtl_can_upgrade(td, NULL)) throtl_upgrade_state(td); |
2e48a530a blk-throttle: mak... |
1201 1202 1203 |
again: parent_sq = sq->parent_sq; dispatched = false; |
e43473b7f blkio: Core imple... |
1204 |
|
7f52f98c2 blk-throttle: imp... |
1205 1206 |
while (true) { throtl_log(sq, "dispatch nr_queued=%u read=%u write=%u", |
2e48a530a blk-throttle: mak... |
1207 1208 |
sq->nr_queued[READ] + sq->nr_queued[WRITE], sq->nr_queued[READ], sq->nr_queued[WRITE]); |
7f52f98c2 blk-throttle: imp... |
1209 1210 1211 |
ret = throtl_select_dispatch(sq); if (ret) { |
7f52f98c2 blk-throttle: imp... |
1212 1213 1214 |
throtl_log(sq, "bios disp=%u", ret); dispatched = true; } |
e43473b7f blkio: Core imple... |
1215 |
|
7f52f98c2 blk-throttle: imp... |
1216 1217 |
if (throtl_schedule_next_dispatch(sq, false)) break; |
e43473b7f blkio: Core imple... |
1218 |
|
7f52f98c2 blk-throttle: imp... |
1219 |
/* this dispatch windows is still open, relax and repeat */ |
0d945c1f9 block: remove the... |
1220 |
spin_unlock_irq(&q->queue_lock); |
7f52f98c2 blk-throttle: imp... |
1221 |
cpu_relax(); |
0d945c1f9 block: remove the... |
1222 |
spin_lock_irq(&q->queue_lock); |
651930bc1 blk-throttle: dis... |
1223 |
} |
e43473b7f blkio: Core imple... |
1224 |
|
2e48a530a blk-throttle: mak... |
1225 1226 |
if (!dispatched) goto out_unlock; |
6e1a5704c blk-throttle: dis... |
1227 |
|
2e48a530a blk-throttle: mak... |
1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 |
if (parent_sq) { /* @parent_sq is another throl_grp, propagate dispatch */ if (tg->flags & THROTL_TG_WAS_EMPTY) { tg_update_disptime(tg); if (!throtl_schedule_next_dispatch(parent_sq, false)) { /* window is already open, repeat dispatching */ sq = parent_sq; tg = sq_to_tg(sq); goto again; } } } else { |
b53b072c4 blk-throttle: Fix... |
1240 |
/* reached the top-level, queue issuing */ |
2e48a530a blk-throttle: mak... |
1241 1242 1243 |
queue_work(kthrotld_workqueue, &td->dispatch_work); } out_unlock: |
0d945c1f9 block: remove the... |
1244 |
spin_unlock_irq(&q->queue_lock); |
6e1a5704c blk-throttle: dis... |
1245 |
} |
e43473b7f blkio: Core imple... |
1246 |
|
6e1a5704c blk-throttle: dis... |
1247 1248 1249 1250 |
/** * blk_throtl_dispatch_work_fn - work function for throtl_data->dispatch_work * @work: work item being executed * |
b53b072c4 blk-throttle: Fix... |
1251 1252 |
* This function is queued for execution when bios reach the bio_lists[] * of throtl_data->service_queue. Those bios are ready and issued by this |
6e1a5704c blk-throttle: dis... |
1253 1254 |
* function. */ |
8876e140e block/blk-throttl... |
1255 |
static void blk_throtl_dispatch_work_fn(struct work_struct *work) |
6e1a5704c blk-throttle: dis... |
1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 |
{ struct throtl_data *td = container_of(work, struct throtl_data, dispatch_work); struct throtl_service_queue *td_sq = &td->service_queue; struct request_queue *q = td->queue; struct bio_list bio_list_on_stack; struct bio *bio; struct blk_plug plug; int rw; bio_list_init(&bio_list_on_stack); |
0d945c1f9 block: remove the... |
1267 |
spin_lock_irq(&q->queue_lock); |
c5cc2070b blk-throttle: add... |
1268 1269 1270 |
for (rw = READ; rw <= WRITE; rw++) while ((bio = throtl_pop_queued(&td_sq->queued[rw], NULL))) bio_list_add(&bio_list_on_stack, bio); |
0d945c1f9 block: remove the... |
1271 |
spin_unlock_irq(&q->queue_lock); |
6e1a5704c blk-throttle: dis... |
1272 1273 |
if (!bio_list_empty(&bio_list_on_stack)) { |
69d60eb96 blk-throttle: Use... |
1274 |
blk_start_plug(&plug); |
ed00aabd5 block: rename gen... |
1275 1276 |
while ((bio = bio_list_pop(&bio_list_on_stack))) submit_bio_noacct(bio); |
69d60eb96 blk-throttle: Use... |
1277 |
blk_finish_plug(&plug); |
e43473b7f blkio: Core imple... |
1278 |
} |
e43473b7f blkio: Core imple... |
1279 |
} |
f95a04afa blkcg: embed stru... |
1280 1281 |
static u64 tg_prfill_conf_u64(struct seq_file *sf, struct blkg_policy_data *pd, int off) |
60c2bc2d5 blkcg: move conf/... |
1282 |
{ |
f95a04afa blkcg: embed stru... |
1283 1284 |
struct throtl_grp *tg = pd_to_tg(pd); u64 v = *(u64 *)((void *)tg + off); |
60c2bc2d5 blkcg: move conf/... |
1285 |
|
2ab5492de blk-throttle: use... |
1286 |
if (v == U64_MAX) |
60c2bc2d5 blkcg: move conf/... |
1287 |
return 0; |
f95a04afa blkcg: embed stru... |
1288 |
return __blkg_prfill_u64(sf, pd, v); |
60c2bc2d5 blkcg: move conf/... |
1289 |
} |
f95a04afa blkcg: embed stru... |
1290 1291 |
static u64 tg_prfill_conf_uint(struct seq_file *sf, struct blkg_policy_data *pd, int off) |
e43473b7f blkio: Core imple... |
1292 |
{ |
f95a04afa blkcg: embed stru... |
1293 1294 |
struct throtl_grp *tg = pd_to_tg(pd); unsigned int v = *(unsigned int *)((void *)tg + off); |
fe0714377 blkio: Recalculat... |
1295 |
|
2ab5492de blk-throttle: use... |
1296 |
if (v == UINT_MAX) |
af133ceb2 blkcg: move blkio... |
1297 |
return 0; |
f95a04afa blkcg: embed stru... |
1298 |
return __blkg_prfill_u64(sf, pd, v); |
e43473b7f blkio: Core imple... |
1299 |
} |
2da8ca822 cgroup: replace c... |
1300 |
static int tg_print_conf_u64(struct seq_file *sf, void *v) |
8e89d13f4 blkio: Implementa... |
1301 |
{ |
2da8ca822 cgroup: replace c... |
1302 1303 |
blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_conf_u64, &blkcg_policy_throtl, seq_cft(sf)->private, false); |
af133ceb2 blkcg: move blkio... |
1304 |
return 0; |
8e89d13f4 blkio: Implementa... |
1305 |
} |
2da8ca822 cgroup: replace c... |
1306 |
static int tg_print_conf_uint(struct seq_file *sf, void *v) |
8e89d13f4 blkio: Implementa... |
1307 |
{ |
2da8ca822 cgroup: replace c... |
1308 1309 |
blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_conf_uint, &blkcg_policy_throtl, seq_cft(sf)->private, false); |
af133ceb2 blkcg: move blkio... |
1310 |
return 0; |
60c2bc2d5 blkcg: move conf/... |
1311 |
} |
9bb67aeb9 blk-throttle: res... |
1312 |
static void tg_conf_updated(struct throtl_grp *tg, bool global) |
60c2bc2d5 blkcg: move conf/... |
1313 |
{ |
69948b070 blkcg: separate o... |
1314 |
struct throtl_service_queue *sq = &tg->service_queue; |
492eb21b9 cgroup: make hier... |
1315 |
struct cgroup_subsys_state *pos_css; |
69948b070 blkcg: separate o... |
1316 |
struct blkcg_gq *blkg; |
af133ceb2 blkcg: move blkio... |
1317 |
|
fda6f272c blk-throttle: imp... |
1318 1319 |
throtl_log(&tg->service_queue, "limit change rbps=%llu wbps=%llu riops=%u wiops=%u", |
9f626e372 blk-throttle: pre... |
1320 1321 |
tg_bps_limit(tg, READ), tg_bps_limit(tg, WRITE), tg_iops_limit(tg, READ), tg_iops_limit(tg, WRITE)); |
632b44935 blk-throttle: rem... |
1322 1323 |
/* |
693e751e7 blk-throttle: imp... |
1324 1325 1326 1327 1328 1329 |
* Update has_rules[] flags for the updated tg's subtree. A tg is * considered to have rules if either the tg itself or any of its * ancestors has rules. This identifies groups without any * restrictions in the whole hierarchy and allows them to bypass * blk-throttle. */ |
9bb67aeb9 blk-throttle: res... |
1330 1331 |
blkg_for_each_descendant_pre(blkg, pos_css, global ? tg->td->queue->root_blkg : tg_to_blkg(tg)) { |
5b81fc3cc blk-throttle: add... |
1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 |
struct throtl_grp *this_tg = blkg_to_tg(blkg); struct throtl_grp *parent_tg; tg_update_has_rules(this_tg); /* ignore root/second level */ if (!cgroup_subsys_on_dfl(io_cgrp_subsys) || !blkg->parent || !blkg->parent->parent) continue; parent_tg = blkg_to_tg(blkg->parent); /* * make sure all children has lower idle time threshold and * higher latency target */ this_tg->idletime_threshold = min(this_tg->idletime_threshold, parent_tg->idletime_threshold); this_tg->latency_target = max(this_tg->latency_target, parent_tg->latency_target); } |
693e751e7 blk-throttle: imp... |
1350 1351 |
/* |
632b44935 blk-throttle: rem... |
1352 1353 1354 1355 1356 1357 1358 |
* We're already holding queue_lock and know @tg is valid. Let's * apply the new config directly. * * Restart the slices for both READ and WRITES. It might happen * that a group's limit are dropped suddenly and we don't want to * account recently dispatched IO with new low rate. */ |
ff8b22c0f blk-throttle: Use... |
1359 1360 |
throtl_start_new_slice(tg, READ); throtl_start_new_slice(tg, WRITE); |
632b44935 blk-throttle: rem... |
1361 |
|
5b2c16aae blk-throttle: sim... |
1362 |
if (tg->flags & THROTL_TG_PENDING) { |
77216b048 blk-throttle: add... |
1363 |
tg_update_disptime(tg); |
7f52f98c2 blk-throttle: imp... |
1364 |
throtl_schedule_next_dispatch(sq->parent_sq, true); |
632b44935 blk-throttle: rem... |
1365 |
} |
69948b070 blkcg: separate o... |
1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 |
} static ssize_t tg_set_conf(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off, bool is_u64) { struct blkcg *blkcg = css_to_blkcg(of_css(of)); struct blkg_conf_ctx ctx; struct throtl_grp *tg; int ret; u64 v; ret = blkg_conf_prep(blkcg, &blkcg_policy_throtl, buf, &ctx); if (ret) return ret; ret = -EINVAL; if (sscanf(ctx.body, "%llu", &v) != 1) goto out_finish; if (!v) |
2ab5492de blk-throttle: use... |
1385 |
v = U64_MAX; |
69948b070 blkcg: separate o... |
1386 1387 1388 1389 1390 1391 1392 |
tg = blkg_to_tg(ctx.blkg); if (is_u64) *(u64 *)((void *)tg + of_cft(of)->private) = v; else *(unsigned int *)((void *)tg + of_cft(of)->private) = v; |
60c2bc2d5 blkcg: move conf/... |
1393 |
|
9bb67aeb9 blk-throttle: res... |
1394 |
tg_conf_updated(tg, false); |
36aa9e5f5 blkcg: move body ... |
1395 1396 |
ret = 0; out_finish: |
60c2bc2d5 blkcg: move conf/... |
1397 |
blkg_conf_finish(&ctx); |
36aa9e5f5 blkcg: move body ... |
1398 |
return ret ?: nbytes; |
8e89d13f4 blkio: Implementa... |
1399 |
} |
451af504d cgroup: replace c... |
1400 1401 |
static ssize_t tg_set_conf_u64(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) |
60c2bc2d5 blkcg: move conf/... |
1402 |
{ |
451af504d cgroup: replace c... |
1403 |
return tg_set_conf(of, buf, nbytes, off, true); |
60c2bc2d5 blkcg: move conf/... |
1404 |
} |
451af504d cgroup: replace c... |
1405 1406 |
static ssize_t tg_set_conf_uint(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) |
60c2bc2d5 blkcg: move conf/... |
1407 |
{ |
451af504d cgroup: replace c... |
1408 |
return tg_set_conf(of, buf, nbytes, off, false); |
60c2bc2d5 blkcg: move conf/... |
1409 |
} |
7ca464383 blk-throtl: stop ... |
1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 |
static int tg_print_rwstat(struct seq_file *sf, void *v) { blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), blkg_prfill_rwstat, &blkcg_policy_throtl, seq_cft(sf)->private, true); return 0; } static u64 tg_prfill_rwstat_recursive(struct seq_file *sf, struct blkg_policy_data *pd, int off) { struct blkg_rwstat_sample sum; blkg_rwstat_recursive_sum(pd_to_blkg(pd), &blkcg_policy_throtl, off, &sum); return __blkg_prfill_rwstat(sf, pd, &sum); } static int tg_print_rwstat_recursive(struct seq_file *sf, void *v) { blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_rwstat_recursive, &blkcg_policy_throtl, seq_cft(sf)->private, true); return 0; } |
880f50e22 blkcg: mark exist... |
1435 |
static struct cftype throtl_legacy_files[] = { |
60c2bc2d5 blkcg: move conf/... |
1436 1437 |
{ .name = "throttle.read_bps_device", |
9f626e372 blk-throttle: pre... |
1438 |
.private = offsetof(struct throtl_grp, bps[READ][LIMIT_MAX]), |
2da8ca822 cgroup: replace c... |
1439 |
.seq_show = tg_print_conf_u64, |
451af504d cgroup: replace c... |
1440 |
.write = tg_set_conf_u64, |
60c2bc2d5 blkcg: move conf/... |
1441 1442 1443 |
}, { .name = "throttle.write_bps_device", |
9f626e372 blk-throttle: pre... |
1444 |
.private = offsetof(struct throtl_grp, bps[WRITE][LIMIT_MAX]), |
2da8ca822 cgroup: replace c... |
1445 |
.seq_show = tg_print_conf_u64, |
451af504d cgroup: replace c... |
1446 |
.write = tg_set_conf_u64, |
60c2bc2d5 blkcg: move conf/... |
1447 1448 1449 |
}, { .name = "throttle.read_iops_device", |
9f626e372 blk-throttle: pre... |
1450 |
.private = offsetof(struct throtl_grp, iops[READ][LIMIT_MAX]), |
2da8ca822 cgroup: replace c... |
1451 |
.seq_show = tg_print_conf_uint, |
451af504d cgroup: replace c... |
1452 |
.write = tg_set_conf_uint, |
60c2bc2d5 blkcg: move conf/... |
1453 1454 1455 |
}, { .name = "throttle.write_iops_device", |
9f626e372 blk-throttle: pre... |
1456 |
.private = offsetof(struct throtl_grp, iops[WRITE][LIMIT_MAX]), |
2da8ca822 cgroup: replace c... |
1457 |
.seq_show = tg_print_conf_uint, |
451af504d cgroup: replace c... |
1458 |
.write = tg_set_conf_uint, |
60c2bc2d5 blkcg: move conf/... |
1459 1460 1461 |
}, { .name = "throttle.io_service_bytes", |
7ca464383 blk-throtl: stop ... |
1462 1463 |
.private = offsetof(struct throtl_grp, stat_bytes), .seq_show = tg_print_rwstat, |
60c2bc2d5 blkcg: move conf/... |
1464 1465 |
}, { |
17534c6f2 blk-throttle: exp... |
1466 |
.name = "throttle.io_service_bytes_recursive", |
7ca464383 blk-throtl: stop ... |
1467 1468 |
.private = offsetof(struct throtl_grp, stat_bytes), .seq_show = tg_print_rwstat_recursive, |
17534c6f2 blk-throttle: exp... |
1469 1470 |
}, { |
60c2bc2d5 blkcg: move conf/... |
1471 |
.name = "throttle.io_serviced", |
7ca464383 blk-throtl: stop ... |
1472 1473 |
.private = offsetof(struct throtl_grp, stat_ios), .seq_show = tg_print_rwstat, |
60c2bc2d5 blkcg: move conf/... |
1474 |
}, |
17534c6f2 blk-throttle: exp... |
1475 1476 |
{ .name = "throttle.io_serviced_recursive", |
7ca464383 blk-throtl: stop ... |
1477 1478 |
.private = offsetof(struct throtl_grp, stat_ios), .seq_show = tg_print_rwstat_recursive, |
17534c6f2 blk-throttle: exp... |
1479 |
}, |
60c2bc2d5 blkcg: move conf/... |
1480 1481 |
{ } /* terminate */ }; |
cd5ab1b0f blk-throttle: add... |
1482 |
static u64 tg_prfill_limit(struct seq_file *sf, struct blkg_policy_data *pd, |
2ee867dcf blkcg: implement ... |
1483 1484 1485 1486 1487 |
int off) { struct throtl_grp *tg = pd_to_tg(pd); const char *dname = blkg_dev_name(pd->blkg); char bufs[4][21] = { "max", "max", "max", "max" }; |
cd5ab1b0f blk-throttle: add... |
1488 1489 |
u64 bps_dft; unsigned int iops_dft; |
ada75b6e5 blk-throttle: add... |
1490 |
char idle_time[26] = ""; |
ec80991d6 blk-throttle: add... |
1491 |
char latency_time[26] = ""; |
2ee867dcf blkcg: implement ... |
1492 1493 1494 |
if (!dname) return 0; |
9f626e372 blk-throttle: pre... |
1495 |
|
cd5ab1b0f blk-throttle: add... |
1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 |
if (off == LIMIT_LOW) { bps_dft = 0; iops_dft = 0; } else { bps_dft = U64_MAX; iops_dft = UINT_MAX; } if (tg->bps_conf[READ][off] == bps_dft && tg->bps_conf[WRITE][off] == bps_dft && tg->iops_conf[READ][off] == iops_dft && |
ada75b6e5 blk-throttle: add... |
1507 |
tg->iops_conf[WRITE][off] == iops_dft && |
ec80991d6 blk-throttle: add... |
1508 |
(off != LIMIT_LOW || |
b4f428ef2 blk-throttle: for... |
1509 |
(tg->idletime_threshold_conf == DFL_IDLE_THRESHOLD && |
5b81fc3cc blk-throttle: add... |
1510 |
tg->latency_target_conf == DFL_LATENCY_TARGET))) |
2ee867dcf blkcg: implement ... |
1511 |
return 0; |
9bb67aeb9 blk-throttle: res... |
1512 |
if (tg->bps_conf[READ][off] != U64_MAX) |
9f626e372 blk-throttle: pre... |
1513 |
snprintf(bufs[0], sizeof(bufs[0]), "%llu", |
cd5ab1b0f blk-throttle: add... |
1514 |
tg->bps_conf[READ][off]); |
9bb67aeb9 blk-throttle: res... |
1515 |
if (tg->bps_conf[WRITE][off] != U64_MAX) |
9f626e372 blk-throttle: pre... |
1516 |
snprintf(bufs[1], sizeof(bufs[1]), "%llu", |
cd5ab1b0f blk-throttle: add... |
1517 |
tg->bps_conf[WRITE][off]); |
9bb67aeb9 blk-throttle: res... |
1518 |
if (tg->iops_conf[READ][off] != UINT_MAX) |
9f626e372 blk-throttle: pre... |
1519 |
snprintf(bufs[2], sizeof(bufs[2]), "%u", |
cd5ab1b0f blk-throttle: add... |
1520 |
tg->iops_conf[READ][off]); |
9bb67aeb9 blk-throttle: res... |
1521 |
if (tg->iops_conf[WRITE][off] != UINT_MAX) |
9f626e372 blk-throttle: pre... |
1522 |
snprintf(bufs[3], sizeof(bufs[3]), "%u", |
cd5ab1b0f blk-throttle: add... |
1523 |
tg->iops_conf[WRITE][off]); |
ada75b6e5 blk-throttle: add... |
1524 |
if (off == LIMIT_LOW) { |
5b81fc3cc blk-throttle: add... |
1525 |
if (tg->idletime_threshold_conf == ULONG_MAX) |
ada75b6e5 blk-throttle: add... |
1526 1527 1528 |
strcpy(idle_time, " idle=max"); else snprintf(idle_time, sizeof(idle_time), " idle=%lu", |
5b81fc3cc blk-throttle: add... |
1529 |
tg->idletime_threshold_conf); |
ec80991d6 blk-throttle: add... |
1530 |
|
5b81fc3cc blk-throttle: add... |
1531 |
if (tg->latency_target_conf == ULONG_MAX) |
ec80991d6 blk-throttle: add... |
1532 1533 1534 |
strcpy(latency_time, " latency=max"); else snprintf(latency_time, sizeof(latency_time), |
5b81fc3cc blk-throttle: add... |
1535 |
" latency=%lu", tg->latency_target_conf); |
ada75b6e5 blk-throttle: add... |
1536 |
} |
2ee867dcf blkcg: implement ... |
1537 |
|
ec80991d6 blk-throttle: add... |
1538 1539 1540 1541 |
seq_printf(sf, "%s rbps=%s wbps=%s riops=%s wiops=%s%s%s ", dname, bufs[0], bufs[1], bufs[2], bufs[3], idle_time, latency_time); |
2ee867dcf blkcg: implement ... |
1542 1543 |
return 0; } |
cd5ab1b0f blk-throttle: add... |
1544 |
static int tg_print_limit(struct seq_file *sf, void *v) |
2ee867dcf blkcg: implement ... |
1545 |
{ |
cd5ab1b0f blk-throttle: add... |
1546 |
blkcg_print_blkgs(sf, css_to_blkcg(seq_css(sf)), tg_prfill_limit, |
2ee867dcf blkcg: implement ... |
1547 1548 1549 |
&blkcg_policy_throtl, seq_cft(sf)->private, false); return 0; } |
cd5ab1b0f blk-throttle: add... |
1550 |
static ssize_t tg_set_limit(struct kernfs_open_file *of, |
2ee867dcf blkcg: implement ... |
1551 1552 1553 1554 1555 1556 |
char *buf, size_t nbytes, loff_t off) { struct blkcg *blkcg = css_to_blkcg(of_css(of)); struct blkg_conf_ctx ctx; struct throtl_grp *tg; u64 v[4]; |
ada75b6e5 blk-throttle: add... |
1557 |
unsigned long idle_time; |
ec80991d6 blk-throttle: add... |
1558 |
unsigned long latency_time; |
2ee867dcf blkcg: implement ... |
1559 |
int ret; |
cd5ab1b0f blk-throttle: add... |
1560 |
int index = of_cft(of)->private; |
2ee867dcf blkcg: implement ... |
1561 1562 1563 1564 1565 1566 |
ret = blkg_conf_prep(blkcg, &blkcg_policy_throtl, buf, &ctx); if (ret) return ret; tg = blkg_to_tg(ctx.blkg); |
cd5ab1b0f blk-throttle: add... |
1567 1568 1569 1570 |
v[0] = tg->bps_conf[READ][index]; v[1] = tg->bps_conf[WRITE][index]; v[2] = tg->iops_conf[READ][index]; v[3] = tg->iops_conf[WRITE][index]; |
2ee867dcf blkcg: implement ... |
1571 |
|
5b81fc3cc blk-throttle: add... |
1572 1573 |
idle_time = tg->idletime_threshold_conf; latency_time = tg->latency_target_conf; |
2ee867dcf blkcg: implement ... |
1574 1575 1576 |
while (true) { char tok[27]; /* wiops=18446744073709551616 */ char *p; |
2ab5492de blk-throttle: use... |
1577 |
u64 val = U64_MAX; |
2ee867dcf blkcg: implement ... |
1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 |
int len; if (sscanf(ctx.body, "%26s%n", tok, &len) != 1) break; if (tok[0] == '\0') break; ctx.body += len; ret = -EINVAL; p = tok; strsep(&p, "="); if (!p || (sscanf(p, "%llu", &val) != 1 && strcmp(p, "max"))) goto out_finish; ret = -ERANGE; if (!val) goto out_finish; ret = -EINVAL; |
5b7048b89 blk-throttle: Fix... |
1597 |
if (!strcmp(tok, "rbps") && val > 1) |
2ee867dcf blkcg: implement ... |
1598 |
v[0] = val; |
5b7048b89 blk-throttle: Fix... |
1599 |
else if (!strcmp(tok, "wbps") && val > 1) |
2ee867dcf blkcg: implement ... |
1600 |
v[1] = val; |
5b7048b89 blk-throttle: Fix... |
1601 |
else if (!strcmp(tok, "riops") && val > 1) |
2ee867dcf blkcg: implement ... |
1602 |
v[2] = min_t(u64, val, UINT_MAX); |
5b7048b89 blk-throttle: Fix... |
1603 |
else if (!strcmp(tok, "wiops") && val > 1) |
2ee867dcf blkcg: implement ... |
1604 |
v[3] = min_t(u64, val, UINT_MAX); |
ada75b6e5 blk-throttle: add... |
1605 1606 |
else if (off == LIMIT_LOW && !strcmp(tok, "idle")) idle_time = val; |
ec80991d6 blk-throttle: add... |
1607 1608 |
else if (off == LIMIT_LOW && !strcmp(tok, "latency")) latency_time = val; |
2ee867dcf blkcg: implement ... |
1609 1610 1611 |
else goto out_finish; } |
cd5ab1b0f blk-throttle: add... |
1612 1613 1614 1615 |
tg->bps_conf[READ][index] = v[0]; tg->bps_conf[WRITE][index] = v[1]; tg->iops_conf[READ][index] = v[2]; tg->iops_conf[WRITE][index] = v[3]; |
2ee867dcf blkcg: implement ... |
1616 |
|
cd5ab1b0f blk-throttle: add... |
1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 |
if (index == LIMIT_MAX) { tg->bps[READ][index] = v[0]; tg->bps[WRITE][index] = v[1]; tg->iops[READ][index] = v[2]; tg->iops[WRITE][index] = v[3]; } tg->bps[READ][LIMIT_LOW] = min(tg->bps_conf[READ][LIMIT_LOW], tg->bps_conf[READ][LIMIT_MAX]); tg->bps[WRITE][LIMIT_LOW] = min(tg->bps_conf[WRITE][LIMIT_LOW], tg->bps_conf[WRITE][LIMIT_MAX]); tg->iops[READ][LIMIT_LOW] = min(tg->iops_conf[READ][LIMIT_LOW], tg->iops_conf[READ][LIMIT_MAX]); tg->iops[WRITE][LIMIT_LOW] = min(tg->iops_conf[WRITE][LIMIT_LOW], tg->iops_conf[WRITE][LIMIT_MAX]); |
b4f428ef2 blk-throttle: for... |
1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 |
tg->idletime_threshold_conf = idle_time; tg->latency_target_conf = latency_time; /* force user to configure all settings for low limit */ if (!(tg->bps[READ][LIMIT_LOW] || tg->iops[READ][LIMIT_LOW] || tg->bps[WRITE][LIMIT_LOW] || tg->iops[WRITE][LIMIT_LOW]) || tg->idletime_threshold_conf == DFL_IDLE_THRESHOLD || tg->latency_target_conf == DFL_LATENCY_TARGET) { tg->bps[READ][LIMIT_LOW] = 0; tg->bps[WRITE][LIMIT_LOW] = 0; tg->iops[READ][LIMIT_LOW] = 0; tg->iops[WRITE][LIMIT_LOW] = 0; tg->idletime_threshold = DFL_IDLE_THRESHOLD; tg->latency_target = DFL_LATENCY_TARGET; } else if (index == LIMIT_LOW) { |
5b81fc3cc blk-throttle: add... |
1646 |
tg->idletime_threshold = tg->idletime_threshold_conf; |
5b81fc3cc blk-throttle: add... |
1647 |
tg->latency_target = tg->latency_target_conf; |
cd5ab1b0f blk-throttle: add... |
1648 |
} |
b4f428ef2 blk-throttle: for... |
1649 1650 1651 1652 1653 1654 1655 |
blk_throtl_update_limit_valid(tg->td); if (tg->td->limit_valid[LIMIT_LOW]) { if (index == LIMIT_LOW) tg->td->limit_index = LIMIT_LOW; } else tg->td->limit_index = LIMIT_MAX; |
9bb67aeb9 blk-throttle: res... |
1656 1657 |
tg_conf_updated(tg, index == LIMIT_LOW && tg->td->limit_valid[LIMIT_LOW]); |
2ee867dcf blkcg: implement ... |
1658 1659 1660 1661 1662 1663 1664 |
ret = 0; out_finish: blkg_conf_finish(&ctx); return ret ?: nbytes; } static struct cftype throtl_files[] = { |
cd5ab1b0f blk-throttle: add... |
1665 1666 1667 1668 1669 1670 1671 1672 1673 |
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW { .name = "low", .flags = CFTYPE_NOT_ON_ROOT, .seq_show = tg_print_limit, .write = tg_set_limit, .private = LIMIT_LOW, }, #endif |
2ee867dcf blkcg: implement ... |
1674 1675 1676 |
{ .name = "max", .flags = CFTYPE_NOT_ON_ROOT, |
cd5ab1b0f blk-throttle: add... |
1677 1678 1679 |
.seq_show = tg_print_limit, .write = tg_set_limit, .private = LIMIT_MAX, |
2ee867dcf blkcg: implement ... |
1680 1681 1682 |
}, { } /* terminate */ }; |
da5277700 block: Move blk_t... |
1683 |
static void throtl_shutdown_wq(struct request_queue *q) |
e43473b7f blkio: Core imple... |
1684 1685 |
{ struct throtl_data *td = q->td; |
69df0ab03 blk-throttle: sep... |
1686 |
cancel_work_sync(&td->dispatch_work); |
e43473b7f blkio: Core imple... |
1687 |
} |
3c798398e blkcg: mass renam... |
1688 |
static struct blkcg_policy blkcg_policy_throtl = { |
2ee867dcf blkcg: implement ... |
1689 |
.dfl_cftypes = throtl_files, |
880f50e22 blkcg: mark exist... |
1690 |
.legacy_cftypes = throtl_legacy_files, |
f9fcc2d39 blkcg: collapse b... |
1691 |
|
001bea73e blkcg: replace bl... |
1692 |
.pd_alloc_fn = throtl_pd_alloc, |
f9fcc2d39 blkcg: collapse b... |
1693 |
.pd_init_fn = throtl_pd_init, |
693e751e7 blk-throttle: imp... |
1694 |
.pd_online_fn = throtl_pd_online, |
cd5ab1b0f blk-throttle: add... |
1695 |
.pd_offline_fn = throtl_pd_offline, |
001bea73e blkcg: replace bl... |
1696 |
.pd_free_fn = throtl_pd_free, |
e43473b7f blkio: Core imple... |
1697 |
}; |
3f0abd806 blk-throttle: add... |
1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 |
static unsigned long __tg_last_low_overflow_time(struct throtl_grp *tg) { unsigned long rtime = jiffies, wtime = jiffies; if (tg->bps[READ][LIMIT_LOW] || tg->iops[READ][LIMIT_LOW]) rtime = tg->last_low_overflow_time[READ]; if (tg->bps[WRITE][LIMIT_LOW] || tg->iops[WRITE][LIMIT_LOW]) wtime = tg->last_low_overflow_time[WRITE]; return min(rtime, wtime); } /* tg should not be an intermediate node */ static unsigned long tg_last_low_overflow_time(struct throtl_grp *tg) { struct throtl_service_queue *parent_sq; struct throtl_grp *parent = tg; unsigned long ret = __tg_last_low_overflow_time(tg); while (true) { parent_sq = parent->service_queue.parent_sq; parent = sq_to_tg(parent_sq); if (!parent) break; /* * The parent doesn't have low limit, it always reaches low * limit. Its overflow time is useless for children */ if (!parent->bps[READ][LIMIT_LOW] && !parent->iops[READ][LIMIT_LOW] && !parent->bps[WRITE][LIMIT_LOW] && !parent->iops[WRITE][LIMIT_LOW]) continue; if (time_after(__tg_last_low_overflow_time(parent), ret)) ret = __tg_last_low_overflow_time(parent); } return ret; } |
9e234eeaf blk-throttle: add... |
1736 1737 1738 1739 1740 |
static bool throtl_tg_is_idle(struct throtl_grp *tg) { /* * cgroup is idle if: * - single idle is too long, longer than a fixed value (in case user |
b4f428ef2 blk-throttle: for... |
1741 |
* configure a too big threshold) or 4 times of idletime threshold |
9e234eeaf blk-throttle: add... |
1742 |
* - average think time is more than threshold |
53696b8d2 blk-throttle: add... |
1743 |
* - IO latency is largely below threshold |
9e234eeaf blk-throttle: add... |
1744 |
*/ |
b4f428ef2 blk-throttle: for... |
1745 |
unsigned long time; |
4cff729f6 blk-throttle: out... |
1746 |
bool ret; |
9e234eeaf blk-throttle: add... |
1747 |
|
b4f428ef2 blk-throttle: for... |
1748 1749 1750 1751 1752 1753 |
time = min_t(unsigned long, MAX_IDLE_TIME, 4 * tg->idletime_threshold); ret = tg->latency_target == DFL_LATENCY_TARGET || tg->idletime_threshold == DFL_IDLE_THRESHOLD || (ktime_get_ns() >> 10) - tg->last_finish_time > time || tg->avg_idletime > tg->idletime_threshold || (tg->latency_target && tg->bio_cnt && |
53696b8d2 blk-throttle: add... |
1754 |
tg->bad_bio_cnt * 5 < tg->bio_cnt); |
4cff729f6 blk-throttle: out... |
1755 1756 1757 1758 1759 |
throtl_log(&tg->service_queue, "avg_idle=%ld, idle_threshold=%ld, bad_bio=%d, total_bio=%d, is_idle=%d, scale=%d", tg->avg_idletime, tg->idletime_threshold, tg->bad_bio_cnt, tg->bio_cnt, ret, tg->td->scale); return ret; |
9e234eeaf blk-throttle: add... |
1760 |
} |
c79892c55 blk-throttle: add... |
1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 |
static bool throtl_tg_can_upgrade(struct throtl_grp *tg) { struct throtl_service_queue *sq = &tg->service_queue; bool read_limit, write_limit; /* * if cgroup reaches low limit (if low limit is 0, the cgroup always * reaches), it's ok to upgrade to next limit */ read_limit = tg->bps[READ][LIMIT_LOW] || tg->iops[READ][LIMIT_LOW]; write_limit = tg->bps[WRITE][LIMIT_LOW] || tg->iops[WRITE][LIMIT_LOW]; if (!read_limit && !write_limit) return true; if (read_limit && sq->nr_queued[READ] && (!write_limit || sq->nr_queued[WRITE])) return true; if (write_limit && sq->nr_queued[WRITE] && (!read_limit || sq->nr_queued[READ])) return true; |
aec242468 blk-throttle: det... |
1780 1781 |
if (time_after_eq(jiffies, |
fa6fb5aab blk-throttle: ign... |
1782 1783 |
tg_last_low_overflow_time(tg) + tg->td->throtl_slice) && throtl_tg_is_idle(tg)) |
aec242468 blk-throttle: det... |
1784 |
return true; |
c79892c55 blk-throttle: add... |
1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 |
return false; } static bool throtl_hierarchy_can_upgrade(struct throtl_grp *tg) { while (true) { if (throtl_tg_can_upgrade(tg)) return true; tg = sq_to_tg(tg->service_queue.parent_sq); if (!tg || !tg_to_blkg(tg)->parent) return false; } return false; } static bool throtl_can_upgrade(struct throtl_data *td, struct throtl_grp *this_tg) { struct cgroup_subsys_state *pos_css; struct blkcg_gq *blkg; if (td->limit_index != LIMIT_LOW) return false; |
297e3d854 blk-throttle: mak... |
1808 |
if (time_before(jiffies, td->low_downgrade_time + td->throtl_slice)) |
3f0abd806 blk-throttle: add... |
1809 |
return false; |
c79892c55 blk-throttle: add... |
1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 |
rcu_read_lock(); blkg_for_each_descendant_post(blkg, pos_css, td->queue->root_blkg) { struct throtl_grp *tg = blkg_to_tg(blkg); if (tg == this_tg) continue; if (!list_empty(&tg_to_blkg(tg)->blkcg->css.children)) continue; if (!throtl_hierarchy_can_upgrade(tg)) { rcu_read_unlock(); return false; } } rcu_read_unlock(); return true; } |
fa6fb5aab blk-throttle: ign... |
1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 |
static void throtl_upgrade_check(struct throtl_grp *tg) { unsigned long now = jiffies; if (tg->td->limit_index != LIMIT_LOW) return; if (time_after(tg->last_check_time + tg->td->throtl_slice, now)) return; tg->last_check_time = now; if (!time_after_eq(now, __tg_last_low_overflow_time(tg) + tg->td->throtl_slice)) return; if (throtl_can_upgrade(tg->td, NULL)) throtl_upgrade_state(tg->td); } |
c79892c55 blk-throttle: add... |
1845 1846 1847 1848 |
static void throtl_upgrade_state(struct throtl_data *td) { struct cgroup_subsys_state *pos_css; struct blkcg_gq *blkg; |
4cff729f6 blk-throttle: out... |
1849 |
throtl_log(&td->service_queue, "upgrade to max"); |
c79892c55 blk-throttle: add... |
1850 |
td->limit_index = LIMIT_MAX; |
3f0abd806 blk-throttle: add... |
1851 |
td->low_upgrade_time = jiffies; |
7394e31fa blk-throttle: mak... |
1852 |
td->scale = 0; |
c79892c55 blk-throttle: add... |
1853 1854 1855 1856 1857 1858 1859 |
rcu_read_lock(); blkg_for_each_descendant_post(blkg, pos_css, td->queue->root_blkg) { struct throtl_grp *tg = blkg_to_tg(blkg); struct throtl_service_queue *sq = &tg->service_queue; tg->disptime = jiffies - 1; throtl_select_dispatch(sq); |
4f02fb761 blk-throttle: fix... |
1860 |
throtl_schedule_next_dispatch(sq, true); |
c79892c55 blk-throttle: add... |
1861 1862 1863 |
} rcu_read_unlock(); throtl_select_dispatch(&td->service_queue); |
4f02fb761 blk-throttle: fix... |
1864 |
throtl_schedule_next_dispatch(&td->service_queue, true); |
c79892c55 blk-throttle: add... |
1865 1866 |
queue_work(kthrotld_workqueue, &td->dispatch_work); } |
4247d9c8b blk-throttle: Rem... |
1867 |
static void throtl_downgrade_state(struct throtl_data *td) |
3f0abd806 blk-throttle: add... |
1868 |
{ |
7394e31fa blk-throttle: mak... |
1869 |
td->scale /= 2; |
4cff729f6 blk-throttle: out... |
1870 |
throtl_log(&td->service_queue, "downgrade, scale %d", td->scale); |
7394e31fa blk-throttle: mak... |
1871 1872 1873 1874 |
if (td->scale) { td->low_upgrade_time = jiffies - td->scale * td->throtl_slice; return; } |
4247d9c8b blk-throttle: Rem... |
1875 |
td->limit_index = LIMIT_LOW; |
3f0abd806 blk-throttle: add... |
1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 |
td->low_downgrade_time = jiffies; } static bool throtl_tg_can_downgrade(struct throtl_grp *tg) { struct throtl_data *td = tg->td; unsigned long now = jiffies; /* * If cgroup is below low limit, consider downgrade and throttle other * cgroups */ |
297e3d854 blk-throttle: mak... |
1888 1889 |
if (time_after_eq(now, td->low_upgrade_time + td->throtl_slice) && time_after_eq(now, tg_last_low_overflow_time(tg) + |
fa6fb5aab blk-throttle: ign... |
1890 1891 1892 |
td->throtl_slice) && (!throtl_tg_is_idle(tg) || !list_empty(&tg_to_blkg(tg)->blkcg->css.children))) |
3f0abd806 blk-throttle: add... |
1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 |
return true; return false; } static bool throtl_hierarchy_can_downgrade(struct throtl_grp *tg) { while (true) { if (!throtl_tg_can_downgrade(tg)) return false; tg = sq_to_tg(tg->service_queue.parent_sq); if (!tg || !tg_to_blkg(tg)->parent) break; } return true; } static void throtl_downgrade_check(struct throtl_grp *tg) { uint64_t bps; unsigned int iops; unsigned long elapsed_time; unsigned long now = jiffies; if (tg->td->limit_index != LIMIT_MAX || !tg->td->limit_valid[LIMIT_LOW]) return; if (!list_empty(&tg_to_blkg(tg)->blkcg->css.children)) return; |
297e3d854 blk-throttle: mak... |
1921 |
if (time_after(tg->last_check_time + tg->td->throtl_slice, now)) |
3f0abd806 blk-throttle: add... |
1922 1923 1924 1925 |
return; elapsed_time = now - tg->last_check_time; tg->last_check_time = now; |
297e3d854 blk-throttle: mak... |
1926 1927 |
if (time_before(now, tg_last_low_overflow_time(tg) + tg->td->throtl_slice)) |
3f0abd806 blk-throttle: add... |
1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 |
return; if (tg->bps[READ][LIMIT_LOW]) { bps = tg->last_bytes_disp[READ] * HZ; do_div(bps, elapsed_time); if (bps >= tg->bps[READ][LIMIT_LOW]) tg->last_low_overflow_time[READ] = now; } if (tg->bps[WRITE][LIMIT_LOW]) { bps = tg->last_bytes_disp[WRITE] * HZ; do_div(bps, elapsed_time); if (bps >= tg->bps[WRITE][LIMIT_LOW]) tg->last_low_overflow_time[WRITE] = now; } if (tg->iops[READ][LIMIT_LOW]) { |
4f1e9630a blk-throtl: optim... |
1945 |
tg->last_io_disp[READ] += atomic_xchg(&tg->last_io_split_cnt[READ], 0); |
3f0abd806 blk-throttle: add... |
1946 1947 1948 1949 1950 1951 |
iops = tg->last_io_disp[READ] * HZ / elapsed_time; if (iops >= tg->iops[READ][LIMIT_LOW]) tg->last_low_overflow_time[READ] = now; } if (tg->iops[WRITE][LIMIT_LOW]) { |
4f1e9630a blk-throtl: optim... |
1952 |
tg->last_io_disp[WRITE] += atomic_xchg(&tg->last_io_split_cnt[WRITE], 0); |
3f0abd806 blk-throttle: add... |
1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 |
iops = tg->last_io_disp[WRITE] * HZ / elapsed_time; if (iops >= tg->iops[WRITE][LIMIT_LOW]) tg->last_low_overflow_time[WRITE] = now; } /* * If cgroup is below low limit, consider downgrade and throttle other * cgroups */ if (throtl_hierarchy_can_downgrade(tg)) |
4247d9c8b blk-throttle: Rem... |
1963 |
throtl_downgrade_state(tg->td); |
3f0abd806 blk-throttle: add... |
1964 1965 1966 1967 1968 1969 |
tg->last_bytes_disp[READ] = 0; tg->last_bytes_disp[WRITE] = 0; tg->last_io_disp[READ] = 0; tg->last_io_disp[WRITE] = 0; } |
9e234eeaf blk-throttle: add... |
1970 1971 |
static void blk_throtl_update_idletime(struct throtl_grp *tg) { |
7901601ae blk-throttle: Avo... |
1972 |
unsigned long now; |
9e234eeaf blk-throttle: add... |
1973 |
unsigned long last_finish_time = tg->last_finish_time; |
7901601ae blk-throttle: Avo... |
1974 1975 1976 1977 1978 |
if (last_finish_time == 0) return; now = ktime_get_ns() >> 10; if (now <= last_finish_time || |
9e234eeaf blk-throttle: add... |
1979 1980 1981 1982 1983 1984 |
last_finish_time == tg->checked_last_finish_time) return; tg->avg_idletime = (tg->avg_idletime * 7 + now - last_finish_time) >> 3; tg->checked_last_finish_time = last_finish_time; } |
b9147dd1b blk-throttle: add... |
1985 1986 1987 |
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW static void throtl_update_latency_buckets(struct throtl_data *td) { |
b889bf66d blk-throttle: tra... |
1988 1989 1990 1991 |
struct avg_latency_bucket avg_latency[2][LATENCY_BUCKET_SIZE]; int i, cpu, rw; unsigned long last_latency[2] = { 0 }; unsigned long latency[2]; |
b9147dd1b blk-throttle: add... |
1992 |
|
b185efa78 blk-throttle: Avo... |
1993 |
if (!blk_queue_nonrot(td->queue) || !td->limit_valid[LIMIT_LOW]) |
b9147dd1b blk-throttle: add... |
1994 1995 1996 1997 1998 1999 |
return; if (time_before(jiffies, td->last_calculate_time + HZ)) return; td->last_calculate_time = jiffies; memset(avg_latency, 0, sizeof(avg_latency)); |
b889bf66d blk-throttle: tra... |
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 |
for (rw = READ; rw <= WRITE; rw++) { for (i = 0; i < LATENCY_BUCKET_SIZE; i++) { struct latency_bucket *tmp = &td->tmp_buckets[rw][i]; for_each_possible_cpu(cpu) { struct latency_bucket *bucket; /* this isn't race free, but ok in practice */ bucket = per_cpu_ptr(td->latency_buckets[rw], cpu); tmp->total_latency += bucket[i].total_latency; tmp->samples += bucket[i].samples; bucket[i].total_latency = 0; bucket[i].samples = 0; } |
b9147dd1b blk-throttle: add... |
2015 |
|
b889bf66d blk-throttle: tra... |
2016 2017 |
if (tmp->samples >= 32) { int samples = tmp->samples; |
b9147dd1b blk-throttle: add... |
2018 |
|
b889bf66d blk-throttle: tra... |
2019 |
latency[rw] = tmp->total_latency; |
b9147dd1b blk-throttle: add... |
2020 |
|
b889bf66d blk-throttle: tra... |
2021 2022 2023 2024 2025 2026 2027 |
tmp->total_latency = 0; tmp->samples = 0; latency[rw] /= samples; if (latency[rw] == 0) continue; avg_latency[rw][i].latency = latency[rw]; } |
b9147dd1b blk-throttle: add... |
2028 2029 |
} } |
b889bf66d blk-throttle: tra... |
2030 2031 2032 2033 2034 2035 2036 2037 |
for (rw = READ; rw <= WRITE; rw++) { for (i = 0; i < LATENCY_BUCKET_SIZE; i++) { if (!avg_latency[rw][i].latency) { if (td->avg_buckets[rw][i].latency < last_latency[rw]) td->avg_buckets[rw][i].latency = last_latency[rw]; continue; } |
b9147dd1b blk-throttle: add... |
2038 |
|
b889bf66d blk-throttle: tra... |
2039 2040 2041 2042 2043 |
if (!td->avg_buckets[rw][i].valid) latency[rw] = avg_latency[rw][i].latency; else latency[rw] = (td->avg_buckets[rw][i].latency * 7 + avg_latency[rw][i].latency) >> 3; |
b9147dd1b blk-throttle: add... |
2044 |
|
b889bf66d blk-throttle: tra... |
2045 2046 2047 2048 2049 |
td->avg_buckets[rw][i].latency = max(latency[rw], last_latency[rw]); td->avg_buckets[rw][i].valid = true; last_latency[rw] = td->avg_buckets[rw][i].latency; } |
b9147dd1b blk-throttle: add... |
2050 |
} |
4cff729f6 blk-throttle: out... |
2051 2052 2053 |
for (i = 0; i < LATENCY_BUCKET_SIZE; i++) throtl_log(&td->service_queue, |
b889bf66d blk-throttle: tra... |
2054 2055 2056 2057 2058 2059 |
"Latency bucket %d: read latency=%ld, read valid=%d, " "write latency=%ld, write valid=%d", i, td->avg_buckets[READ][i].latency, td->avg_buckets[READ][i].valid, td->avg_buckets[WRITE][i].latency, td->avg_buckets[WRITE][i].valid); |
b9147dd1b blk-throttle: add... |
2060 2061 2062 2063 2064 2065 |
} #else static inline void throtl_update_latency_buckets(struct throtl_data *td) { } #endif |
4f1e9630a blk-throtl: optim... |
2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 |
void blk_throtl_charge_bio_split(struct bio *bio) { struct blkcg_gq *blkg = bio->bi_blkg; struct throtl_grp *parent = blkg_to_tg(blkg); struct throtl_service_queue *parent_sq; bool rw = bio_data_dir(bio); do { if (!parent->has_rules[rw]) break; atomic_inc(&parent->io_split_cnt[rw]); atomic_inc(&parent->last_io_split_cnt[rw]); parent_sq = parent->service_queue.parent_sq; parent = sq_to_tg(parent_sq); } while (parent); } |
db18a53e5 blk-cgroup: remov... |
2084 |
bool blk_throtl_bio(struct bio *bio) |
e43473b7f blkio: Core imple... |
2085 |
{ |
309dca309 block: store a bl... |
2086 |
struct request_queue *q = bio->bi_bdev->bd_disk->queue; |
db18a53e5 blk-cgroup: remov... |
2087 |
struct blkcg_gq *blkg = bio->bi_blkg; |
c5cc2070b blk-throttle: add... |
2088 |
struct throtl_qnode *qn = NULL; |
a2e83ef9c blk-cgroup: remov... |
2089 |
struct throtl_grp *tg = blkg_to_tg(blkg); |
73f0d49a9 blk-throttle: mov... |
2090 |
struct throtl_service_queue *sq; |
0e9f4164b blk-throttle: gen... |
2091 |
bool rw = bio_data_dir(bio); |
bc16a4f93 block: reorganize... |
2092 |
bool throttled = false; |
b9147dd1b blk-throttle: add... |
2093 |
struct throtl_data *td = tg->td; |
e43473b7f blkio: Core imple... |
2094 |
|
93b806380 blk-cgroup: move ... |
2095 |
rcu_read_lock(); |
ae1188963 blkcg: consolidat... |
2096 |
|
2a0f61e6e blk-throttle: set... |
2097 |
/* see throtl_charge_bio() */ |
7ca464383 blk-throtl: stop ... |
2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 |
if (bio_flagged(bio, BIO_THROTTLED)) goto out; if (!cgroup_subsys_on_dfl(io_cgrp_subsys)) { blkg_rwstat_add(&tg->stat_bytes, bio->bi_opf, bio->bi_iter.bi_size); blkg_rwstat_add(&tg->stat_ios, bio->bi_opf, 1); } if (!tg->has_rules[rw]) |
bc16a4f93 block: reorganize... |
2108 |
goto out; |
e43473b7f blkio: Core imple... |
2109 |
|
0d945c1f9 block: remove the... |
2110 |
spin_lock_irq(&q->queue_lock); |
c9589f03e blk-throttle: imp... |
2111 |
|
b9147dd1b blk-throttle: add... |
2112 |
throtl_update_latency_buckets(td); |
9e234eeaf blk-throttle: add... |
2113 |
blk_throtl_update_idletime(tg); |
73f0d49a9 blk-throttle: mov... |
2114 |
sq = &tg->service_queue; |
c79892c55 blk-throttle: add... |
2115 |
again: |
9e660acff blk-throttle: mak... |
2116 |
while (true) { |
3f0abd806 blk-throttle: add... |
2117 2118 2119 |
if (tg->last_low_overflow_time[rw] == 0) tg->last_low_overflow_time[rw] = jiffies; throtl_downgrade_check(tg); |
fa6fb5aab blk-throttle: ign... |
2120 |
throtl_upgrade_check(tg); |
9e660acff blk-throttle: mak... |
2121 2122 2123 |
/* throtl is FIFO - if bios are already queued, should queue */ if (sq->nr_queued[rw]) break; |
de701c74a blk-throttle: Som... |
2124 |
|
9e660acff blk-throttle: mak... |
2125 |
/* if above limits, break to queue */ |
c79892c55 blk-throttle: add... |
2126 |
if (!tg_may_dispatch(tg, bio, NULL)) { |
3f0abd806 blk-throttle: add... |
2127 |
tg->last_low_overflow_time[rw] = jiffies; |
b9147dd1b blk-throttle: add... |
2128 2129 |
if (throtl_can_upgrade(td, tg)) { throtl_upgrade_state(td); |
c79892c55 blk-throttle: add... |
2130 2131 |
goto again; } |
9e660acff blk-throttle: mak... |
2132 |
break; |
c79892c55 blk-throttle: add... |
2133 |
} |
9e660acff blk-throttle: mak... |
2134 2135 |
/* within limits, let's charge and dispatch directly */ |
e43473b7f blkio: Core imple... |
2136 |
throtl_charge_bio(tg, bio); |
04521db04 blk-throttle: Res... |
2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 |
/* * We need to trim slice even when bios are not being queued * otherwise it might happen that a bio is not queued for * a long time and slice keeps on extending and trim is not * called for a long time. Now if limits are reduced suddenly * we take into account all the IO dispatched so far at new * low rate and * newly queued IO gets a really long dispatch * time. * * So keep on trimming slice even if bio is not queued. */ |
0f3457f60 blk-throttle: add... |
2149 |
throtl_trim_slice(tg, rw); |
9e660acff blk-throttle: mak... |
2150 2151 2152 |
/* * @bio passed through this layer without being throttled. |
b53b072c4 blk-throttle: Fix... |
2153 |
* Climb up the ladder. If we're already at the top, it |
9e660acff blk-throttle: mak... |
2154 2155 |
* can be executed directly. */ |
c5cc2070b blk-throttle: add... |
2156 |
qn = &tg->qnode_on_parent[rw]; |
9e660acff blk-throttle: mak... |
2157 2158 2159 2160 |
sq = sq->parent_sq; tg = sq_to_tg(sq); if (!tg) goto out_unlock; |
e43473b7f blkio: Core imple... |
2161 |
} |
9e660acff blk-throttle: mak... |
2162 |
/* out-of-limit, queue to @tg */ |
fda6f272c blk-throttle: imp... |
2163 2164 |
throtl_log(sq, "[%c] bio. bdisp=%llu sz=%u bps=%llu iodisp=%u iops=%u queued=%d/%d", rw == READ ? 'R' : 'W', |
9f626e372 blk-throttle: pre... |
2165 2166 2167 |
tg->bytes_disp[rw], bio->bi_iter.bi_size, tg_bps_limit(tg, rw), tg->io_disp[rw], tg_iops_limit(tg, rw), |
fda6f272c blk-throttle: imp... |
2168 |
sq->nr_queued[READ], sq->nr_queued[WRITE]); |
e43473b7f blkio: Core imple... |
2169 |
|
3f0abd806 blk-throttle: add... |
2170 |
tg->last_low_overflow_time[rw] = jiffies; |
b9147dd1b blk-throttle: add... |
2171 |
td->nr_queued[rw]++; |
c5cc2070b blk-throttle: add... |
2172 |
throtl_add_bio_tg(bio, qn, tg); |
bc16a4f93 block: reorganize... |
2173 |
throttled = true; |
e43473b7f blkio: Core imple... |
2174 |
|
7f52f98c2 blk-throttle: imp... |
2175 2176 2177 2178 2179 2180 |
/* * Update @tg's dispatch time and force schedule dispatch if @tg * was empty before @bio. The forced scheduling isn't likely to * cause undue delay as @bio is likely to be dispatched directly if * its @tg's disptime is not in the future. */ |
0e9f4164b blk-throttle: gen... |
2181 |
if (tg->flags & THROTL_TG_WAS_EMPTY) { |
77216b048 blk-throttle: add... |
2182 |
tg_update_disptime(tg); |
7f52f98c2 blk-throttle: imp... |
2183 |
throtl_schedule_next_dispatch(tg->service_queue.parent_sq, true); |
e43473b7f blkio: Core imple... |
2184 |
} |
bc16a4f93 block: reorganize... |
2185 |
out_unlock: |
0d945c1f9 block: remove the... |
2186 |
spin_unlock_irq(&q->queue_lock); |
bc16a4f93 block: reorganize... |
2187 |
out: |
111be8839 block-throttle: a... |
2188 |
bio_set_flag(bio, BIO_THROTTLED); |
b9147dd1b blk-throttle: add... |
2189 2190 2191 |
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW if (throttled || !td->track_bio_latency) |
5238dcf41 block: replace bi... |
2192 |
bio->bi_issue.value |= BIO_ISSUE_THROTL_SKIP_LATENCY; |
b9147dd1b blk-throttle: add... |
2193 |
#endif |
93b806380 blk-cgroup: move ... |
2194 |
rcu_read_unlock(); |
bc16a4f93 block: reorganize... |
2195 |
return throttled; |
e43473b7f blkio: Core imple... |
2196 |
} |
9e234eeaf blk-throttle: add... |
2197 |
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW |
b9147dd1b blk-throttle: add... |
2198 2199 2200 2201 2202 |
static void throtl_track_latency(struct throtl_data *td, sector_t size, int op, unsigned long time) { struct latency_bucket *latency; int index; |
b889bf66d blk-throttle: tra... |
2203 2204 |
if (!td || td->limit_index != LIMIT_LOW || !(op == REQ_OP_READ || op == REQ_OP_WRITE) || |
b9147dd1b blk-throttle: add... |
2205 2206 2207 2208 |
!blk_queue_nonrot(td->queue)) return; index = request_bucket_index(size); |
b889bf66d blk-throttle: tra... |
2209 |
latency = get_cpu_ptr(td->latency_buckets[op]); |
b9147dd1b blk-throttle: add... |
2210 2211 |
latency[index].total_latency += time; latency[index].samples++; |
b889bf66d blk-throttle: tra... |
2212 |
put_cpu_ptr(td->latency_buckets[op]); |
b9147dd1b blk-throttle: add... |
2213 2214 2215 2216 2217 2218 |
} void blk_throtl_stat_add(struct request *rq, u64 time_ns) { struct request_queue *q = rq->q; struct throtl_data *td = q->td; |
3d2443069 block: make rq se... |
2219 2220 |
throtl_track_latency(td, blk_rq_stats_sectors(rq), req_op(rq), time_ns >> 10); |
b9147dd1b blk-throttle: add... |
2221 |
} |
9e234eeaf blk-throttle: add... |
2222 2223 |
void blk_throtl_bio_endio(struct bio *bio) { |
08e18eab0 block: add bi_blk... |
2224 |
struct blkcg_gq *blkg; |
9e234eeaf blk-throttle: add... |
2225 |
struct throtl_grp *tg; |
b9147dd1b blk-throttle: add... |
2226 2227 2228 2229 |
u64 finish_time_ns; unsigned long finish_time; unsigned long start_time; unsigned long lat; |
b889bf66d blk-throttle: tra... |
2230 |
int rw = bio_data_dir(bio); |
9e234eeaf blk-throttle: add... |
2231 |
|
08e18eab0 block: add bi_blk... |
2232 2233 |
blkg = bio->bi_blkg; if (!blkg) |
9e234eeaf blk-throttle: add... |
2234 |
return; |
08e18eab0 block: add bi_blk... |
2235 |
tg = blkg_to_tg(blkg); |
b185efa78 blk-throttle: Avo... |
2236 2237 |
if (!tg->td->limit_valid[LIMIT_LOW]) return; |
9e234eeaf blk-throttle: add... |
2238 |
|
b9147dd1b blk-throttle: add... |
2239 2240 |
finish_time_ns = ktime_get_ns(); tg->last_finish_time = finish_time_ns >> 10; |
5238dcf41 block: replace bi... |
2241 2242 |
start_time = bio_issue_time(&bio->bi_issue) >> 10; finish_time = __bio_issue_time(finish_time_ns) >> 10; |
08e18eab0 block: add bi_blk... |
2243 |
if (!start_time || finish_time <= start_time) |
53696b8d2 blk-throttle: add... |
2244 2245 2246 |
return; lat = finish_time - start_time; |
b9147dd1b blk-throttle: add... |
2247 |
/* this is only for bio based driver */ |
5238dcf41 block: replace bi... |
2248 2249 2250 |
if (!(bio->bi_issue.value & BIO_ISSUE_THROTL_SKIP_LATENCY)) throtl_track_latency(tg->td, bio_issue_size(&bio->bi_issue), bio_op(bio), lat); |
53696b8d2 blk-throttle: add... |
2251 |
|
6679a90c4 blk-throttle: set... |
2252 |
if (tg->latency_target && lat >= tg->td->filtered_latency) { |
53696b8d2 blk-throttle: add... |
2253 2254 |
int bucket; unsigned int threshold; |
5238dcf41 block: replace bi... |
2255 |
bucket = request_bucket_index(bio_issue_size(&bio->bi_issue)); |
b889bf66d blk-throttle: tra... |
2256 |
threshold = tg->td->avg_buckets[rw][bucket].latency + |
53696b8d2 blk-throttle: add... |
2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 |
tg->latency_target; if (lat > threshold) tg->bad_bio_cnt++; /* * Not race free, could get wrong count, which means cgroups * will be throttled */ tg->bio_cnt++; } if (time_after(jiffies, tg->bio_cnt_reset_time) || tg->bio_cnt > 1024) { tg->bio_cnt_reset_time = tg->td->throtl_slice + jiffies; tg->bio_cnt /= 2; tg->bad_bio_cnt /= 2; |
b9147dd1b blk-throttle: add... |
2271 |
} |
9e234eeaf blk-throttle: add... |
2272 2273 |
} #endif |
e43473b7f blkio: Core imple... |
2274 2275 2276 |
int blk_throtl_init(struct request_queue *q) { struct throtl_data *td; |
a2b1693ba blkcg: implement ... |
2277 |
int ret; |
e43473b7f blkio: Core imple... |
2278 2279 2280 2281 |
td = kzalloc_node(sizeof(*td), GFP_KERNEL, q->node); if (!td) return -ENOMEM; |
b889bf66d blk-throttle: tra... |
2282 |
td->latency_buckets[READ] = __alloc_percpu(sizeof(struct latency_bucket) * |
b9147dd1b blk-throttle: add... |
2283 |
LATENCY_BUCKET_SIZE, __alignof__(u64)); |
b889bf66d blk-throttle: tra... |
2284 2285 2286 2287 2288 |
if (!td->latency_buckets[READ]) { kfree(td); return -ENOMEM; } td->latency_buckets[WRITE] = __alloc_percpu(sizeof(struct latency_bucket) * |
b9147dd1b blk-throttle: add... |
2289 |
LATENCY_BUCKET_SIZE, __alignof__(u64)); |
b889bf66d blk-throttle: tra... |
2290 2291 |
if (!td->latency_buckets[WRITE]) { free_percpu(td->latency_buckets[READ]); |
b9147dd1b blk-throttle: add... |
2292 2293 2294 |
kfree(td); return -ENOMEM; } |
e43473b7f blkio: Core imple... |
2295 |
|
69df0ab03 blk-throttle: sep... |
2296 |
INIT_WORK(&td->dispatch_work, blk_throtl_dispatch_work_fn); |
b2ce2643c blk-throttle: cle... |
2297 |
throtl_service_queue_init(&td->service_queue); |
e43473b7f blkio: Core imple... |
2298 |
|
cd1604fab blkcg: factor out... |
2299 |
q->td = td; |
29b125892 blk-throttle: Dyn... |
2300 |
td->queue = q; |
02977e4af blkio: Add root g... |
2301 |
|
9f626e372 blk-throttle: pre... |
2302 |
td->limit_valid[LIMIT_MAX] = true; |
cd5ab1b0f blk-throttle: add... |
2303 |
td->limit_index = LIMIT_MAX; |
3f0abd806 blk-throttle: add... |
2304 2305 |
td->low_upgrade_time = jiffies; td->low_downgrade_time = jiffies; |
9e234eeaf blk-throttle: add... |
2306 |
|
a2b1693ba blkcg: implement ... |
2307 |
/* activate policy */ |
3c798398e blkcg: mass renam... |
2308 |
ret = blkcg_activate_policy(q, &blkcg_policy_throtl); |
b9147dd1b blk-throttle: add... |
2309 |
if (ret) { |
b889bf66d blk-throttle: tra... |
2310 2311 |
free_percpu(td->latency_buckets[READ]); free_percpu(td->latency_buckets[WRITE]); |
f51b802c1 blkcg: use the us... |
2312 |
kfree(td); |
b9147dd1b blk-throttle: add... |
2313 |
} |
a2b1693ba blkcg: implement ... |
2314 |
return ret; |
e43473b7f blkio: Core imple... |
2315 2316 2317 2318 |
} void blk_throtl_exit(struct request_queue *q) { |
c875f4d02 blkcg: drop unnec... |
2319 |
BUG_ON(!q->td); |
884f0e84f blk-throttle: fix... |
2320 |
del_timer_sync(&q->td->service_queue.pending_timer); |
da5277700 block: Move blk_t... |
2321 |
throtl_shutdown_wq(q); |
3c798398e blkcg: mass renam... |
2322 |
blkcg_deactivate_policy(q, &blkcg_policy_throtl); |
b889bf66d blk-throttle: tra... |
2323 2324 |
free_percpu(q->td->latency_buckets[READ]); free_percpu(q->td->latency_buckets[WRITE]); |
c9a929dde block: fix reques... |
2325 |
kfree(q->td); |
e43473b7f blkio: Core imple... |
2326 |
} |
d61fcfa4b blk-throttle: cho... |
2327 2328 2329 |
void blk_throtl_register_queue(struct request_queue *q) { struct throtl_data *td; |
6679a90c4 blk-throttle: set... |
2330 |
int i; |
d61fcfa4b blk-throttle: cho... |
2331 2332 2333 |
td = q->td; BUG_ON(!td); |
6679a90c4 blk-throttle: set... |
2334 |
if (blk_queue_nonrot(q)) { |
d61fcfa4b blk-throttle: cho... |
2335 |
td->throtl_slice = DFL_THROTL_SLICE_SSD; |
6679a90c4 blk-throttle: set... |
2336 2337 |
td->filtered_latency = LATENCY_FILTERED_SSD; } else { |
d61fcfa4b blk-throttle: cho... |
2338 |
td->throtl_slice = DFL_THROTL_SLICE_HD; |
6679a90c4 blk-throttle: set... |
2339 |
td->filtered_latency = LATENCY_FILTERED_HD; |
b889bf66d blk-throttle: tra... |
2340 2341 2342 2343 |
for (i = 0; i < LATENCY_BUCKET_SIZE; i++) { td->avg_buckets[READ][i].latency = DFL_HD_BASELINE_LATENCY; td->avg_buckets[WRITE][i].latency = DFL_HD_BASELINE_LATENCY; } |
6679a90c4 blk-throttle: set... |
2344 |
} |
d61fcfa4b blk-throttle: cho... |
2345 2346 2347 2348 |
#ifndef CONFIG_BLK_DEV_THROTTLING_LOW /* if no low limit, use previous default */ td->throtl_slice = DFL_THROTL_SLICE_HD; #endif |
9e234eeaf blk-throttle: add... |
2349 |
|
344e9ffcb block: add queue_... |
2350 |
td->track_bio_latency = !queue_is_mq(q); |
b9147dd1b blk-throttle: add... |
2351 2352 |
if (!td->track_bio_latency) blk_stat_enable_accounting(q); |
d61fcfa4b blk-throttle: cho... |
2353 |
} |
297e3d854 blk-throttle: mak... |
2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 |
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW ssize_t blk_throtl_sample_time_show(struct request_queue *q, char *page) { if (!q->td) return -EINVAL; return sprintf(page, "%u ", jiffies_to_msecs(q->td->throtl_slice)); } ssize_t blk_throtl_sample_time_store(struct request_queue *q, const char *page, size_t count) { unsigned long v; unsigned long t; if (!q->td) return -EINVAL; if (kstrtoul(page, 10, &v)) return -EINVAL; t = msecs_to_jiffies(v); if (t == 0 || t > MAX_THROTL_SLICE) return -EINVAL; q->td->throtl_slice = t; return count; } #endif |
e43473b7f blkio: Core imple... |
2380 2381 |
static int __init throtl_init(void) { |
450adcbe5 blk-throttle: Do ... |
2382 2383 2384 2385 |
kthrotld_workqueue = alloc_workqueue("kthrotld", WQ_MEM_RECLAIM, 0); if (!kthrotld_workqueue) panic("Failed to create kthrotld "); |
3c798398e blkcg: mass renam... |
2386 |
return blkcg_policy_register(&blkcg_policy_throtl); |
e43473b7f blkio: Core imple... |
2387 2388 2389 |
} module_init(throtl_init); |