From 102a0743326a03cd1a1202ceda21e175b7d3575c Mon Sep 17 00:00:00 2001 From: hc <hc@nodka.com> Date: Tue, 20 Feb 2024 01:20:52 +0000 Subject: [PATCH] add new system file --- kernel/block/blk-rq-qos.c | 178 +++++++++++++++++++++++++++++++++++++++++++++++------------ 1 files changed, 142 insertions(+), 36 deletions(-) diff --git a/kernel/block/blk-rq-qos.c b/kernel/block/blk-rq-qos.c index 43bcd4e..e83af7b 100644 --- a/kernel/block/blk-rq-qos.c +++ b/kernel/block/blk-rq-qos.c @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: GPL-2.0 + #include "blk-rq-qos.h" /* @@ -27,75 +29,85 @@ return atomic_inc_below(&rq_wait->inflight, limit); } -void rq_qos_cleanup(struct request_queue *q, struct bio *bio) +void __rq_qos_cleanup(struct rq_qos *rqos, struct bio *bio) { - struct rq_qos *rqos; - - for (rqos = q->rq_qos; rqos; rqos = rqos->next) { + do { if (rqos->ops->cleanup) rqos->ops->cleanup(rqos, bio); - } + rqos = rqos->next; + } while (rqos); } -void rq_qos_done(struct request_queue *q, struct request *rq) +void __rq_qos_done(struct rq_qos *rqos, struct request *rq) { - struct rq_qos *rqos; - - for (rqos = q->rq_qos; rqos; rqos = rqos->next) { + do { if (rqos->ops->done) rqos->ops->done(rqos, rq); - } + rqos = rqos->next; + } while (rqos); } -void rq_qos_issue(struct request_queue *q, struct request *rq) +void __rq_qos_issue(struct rq_qos *rqos, struct request *rq) { - struct rq_qos *rqos; - - for(rqos = q->rq_qos; rqos; rqos = rqos->next) { + do { if (rqos->ops->issue) rqos->ops->issue(rqos, rq); - } + rqos = rqos->next; + } while (rqos); } -void rq_qos_requeue(struct request_queue *q, struct request *rq) +void __rq_qos_requeue(struct rq_qos *rqos, struct request *rq) { - struct rq_qos *rqos; - - for(rqos = q->rq_qos; rqos; rqos = rqos->next) { + do { if (rqos->ops->requeue) rqos->ops->requeue(rqos, rq); - } + rqos = rqos->next; + } while (rqos); } -void rq_qos_throttle(struct request_queue *q, struct bio *bio, - spinlock_t *lock) +void __rq_qos_throttle(struct rq_qos *rqos, struct bio *bio) { - struct rq_qos *rqos; - - for(rqos = q->rq_qos; rqos; rqos = rqos->next) { + do { if (rqos->ops->throttle) - rqos->ops->throttle(rqos, bio, lock); - } + rqos->ops->throttle(rqos, bio); + rqos = rqos->next; + } while (rqos); } -void rq_qos_track(struct request_queue *q, struct request *rq, struct bio *bio) +void __rq_qos_track(struct rq_qos *rqos, struct request *rq, struct bio *bio) { - struct rq_qos *rqos; - - for(rqos = q->rq_qos; rqos; rqos = rqos->next) { + do { if (rqos->ops->track) rqos->ops->track(rqos, rq, bio); - } + rqos = rqos->next; + } while (rqos); } -void rq_qos_done_bio(struct request_queue *q, struct bio *bio) +void __rq_qos_merge(struct rq_qos *rqos, struct request *rq, struct bio *bio) { - struct rq_qos *rqos; + do { + if (rqos->ops->merge) + rqos->ops->merge(rqos, rq, bio); + rqos = rqos->next; + } while (rqos); +} - for(rqos = q->rq_qos; rqos; rqos = rqos->next) { +void __rq_qos_done_bio(struct rq_qos *rqos, struct bio *bio) +{ + do { if (rqos->ops->done_bio) rqos->ops->done_bio(rqos, bio); - } + rqos = rqos->next; + } while (rqos); +} + +void __rq_qos_queue_depth_changed(struct rq_qos *rqos) +{ + do { + if (rqos->ops->queue_depth_changed) + rqos->ops->queue_depth_changed(rqos); + rqos = rqos->next; + } while (rqos); } /* @@ -188,8 +200,102 @@ return true; } +struct rq_qos_wait_data { + struct wait_queue_entry wq; + struct task_struct *task; + struct rq_wait *rqw; + acquire_inflight_cb_t *cb; + void *private_data; + bool got_token; +}; + +static int rq_qos_wake_function(struct wait_queue_entry *curr, + unsigned int mode, int wake_flags, void *key) +{ + struct rq_qos_wait_data *data = container_of(curr, + struct rq_qos_wait_data, + wq); + + /* + * If we fail to get a budget, return -1 to interrupt the wake up loop + * in __wake_up_common. + */ + if (!data->cb(data->rqw, data->private_data)) + return -1; + + data->got_token = true; + smp_wmb(); + list_del_init(&curr->entry); + wake_up_process(data->task); + return 1; +} + +/** + * rq_qos_wait - throttle on a rqw if we need to + * @rqw: rqw to throttle on + * @private_data: caller provided specific data + * @acquire_inflight_cb: inc the rqw->inflight counter if we can + * @cleanup_cb: the callback to cleanup in case we race with a waker + * + * This provides a uniform place for the rq_qos users to do their throttling. + * Since you can end up with a lot of things sleeping at once, this manages the + * waking up based on the resources available. The acquire_inflight_cb should + * inc the rqw->inflight if we have the ability to do so, or return false if not + * and then we will sleep until the room becomes available. + * + * cleanup_cb is in case that we race with a waker and need to cleanup the + * inflight count accordingly. + */ +void rq_qos_wait(struct rq_wait *rqw, void *private_data, + acquire_inflight_cb_t *acquire_inflight_cb, + cleanup_cb_t *cleanup_cb) +{ + struct rq_qos_wait_data data = { + .wq = { + .func = rq_qos_wake_function, + .entry = LIST_HEAD_INIT(data.wq.entry), + }, + .task = current, + .rqw = rqw, + .cb = acquire_inflight_cb, + .private_data = private_data, + }; + bool has_sleeper; + + has_sleeper = wq_has_sleeper(&rqw->wait); + if (!has_sleeper && acquire_inflight_cb(rqw, private_data)) + return; + + has_sleeper = !prepare_to_wait_exclusive(&rqw->wait, &data.wq, + TASK_UNINTERRUPTIBLE); + do { + /* The memory barrier in set_task_state saves us here. */ + if (data.got_token) + break; + if (!has_sleeper && acquire_inflight_cb(rqw, private_data)) { + finish_wait(&rqw->wait, &data.wq); + + /* + * We raced with wbt_wake_function() getting a token, + * which means we now have two. Put our local token + * and wake anyone else potentially waiting for one. + */ + smp_rmb(); + if (data.got_token) + cleanup_cb(rqw, private_data); + break; + } + io_schedule(); + has_sleeper = true; + set_current_state(TASK_UNINTERRUPTIBLE); + } while (1); + finish_wait(&rqw->wait, &data.wq); +} + void rq_qos_exit(struct request_queue *q) { + blk_mq_debugfs_unregister_queue_rqos(q); + while (q->rq_qos) { struct rq_qos *rqos = q->rq_qos; q->rq_qos = rqos->next; -- Gitblit v1.6.2