diff options
Diffstat (limited to 'fs/btrfs/async-thread.c')
| -rw-r--r-- | fs/btrfs/async-thread.c | 848 |
1 files changed, 227 insertions, 621 deletions
diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c index c1e0b0caf9cc..ecb5832c0967 100644 --- a/fs/btrfs/async-thread.c +++ b/fs/btrfs/async-thread.c @@ -1,5 +1,6 @@ /* * Copyright (C) 2007 Oracle. All rights reserved. + * Copyright (C) 2014 Fujitsu. All rights reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public @@ -21,708 +22,313 @@ #include <linux/list.h> #include <linux/spinlock.h> #include <linux/freezer.h> +#include <linux/workqueue.h> #include "async-thread.h" +#include "ctree.h" + +#define WORK_DONE_BIT 0 +#define WORK_ORDER_DONE_BIT 1 +#define WORK_HIGH_PRIO_BIT 2 + +#define NO_THRESHOLD (-1) +#define DFT_THRESHOLD (32) + +struct __btrfs_workqueue { + struct workqueue_struct *normal_wq; + /* List head pointing to ordered work list */ + struct list_head ordered_list; + + /* Spinlock for ordered_list */ + spinlock_t list_lock; + + /* Thresholding related variants */ + atomic_t pending; + int max_active; + int current_max; + int thresh; + unsigned int count; + spinlock_t thres_lock; +}; -#define WORK_QUEUED_BIT 0 -#define WORK_DONE_BIT 1 -#define WORK_ORDER_DONE_BIT 2 -#define WORK_HIGH_PRIO_BIT 3 - -/* - * container for the kthread task pointer and the list of pending work - * One of these is allocated per thread. - */ -struct btrfs_worker_thread { - /* pool we belong to */ - struct btrfs_workers *workers; - - /* list of struct btrfs_work that are waiting for service */ - struct list_head pending; - struct list_head prio_pending; - - /* list of worker threads from struct btrfs_workers */ - struct list_head worker_list; - - /* kthread */ - struct task_struct *task; +struct btrfs_workqueue { + struct __btrfs_workqueue *normal; + struct __btrfs_workqueue *high; +}; - /* number of things on the pending list */ - atomic_t num_pending; +static inline struct __btrfs_workqueue +*__btrfs_alloc_workqueue(const char *name, int flags, int max_active, + int thresh) +{ + struct __btrfs_workqueue *ret = kzalloc(sizeof(*ret), GFP_NOFS); - /* reference counter for this struct */ - atomic_t refs; + if (unlikely(!ret)) + return NULL; - unsigned long sequence; + ret->max_active = max_active; + atomic_set(&ret->pending, 0); + if (thresh == 0) + thresh = DFT_THRESHOLD; + /* For low threshold, disabling threshold is a better choice */ + if (thresh < DFT_THRESHOLD) { + ret->current_max = max_active; + ret->thresh = NO_THRESHOLD; + } else { + ret->current_max = 1; + ret->thresh = thresh; + } - /* protects the pending list. */ - spinlock_t lock; + if (flags & WQ_HIGHPRI) + ret->normal_wq = alloc_workqueue("%s-%s-high", flags, + ret->max_active, + "btrfs", name); + else + ret->normal_wq = alloc_workqueue("%s-%s", flags, + ret->max_active, "btrfs", + name); + if (unlikely(!ret->normal_wq)) { + kfree(ret); + return NULL; + } - /* set to non-zero when this thread is already awake and kicking */ - int working; + INIT_LIST_HEAD(&ret->ordered_list); + spin_lock_init(&ret->list_lock); + spin_lock_init(&ret->thres_lock); + trace_btrfs_workqueue_alloc(ret, name, flags & WQ_HIGHPRI); + return ret; +} - /* are we currently idle */ - int idle; -}; +static inline void +__btrfs_destroy_workqueue(struct __btrfs_workqueue *wq); -static int __btrfs_start_workers(struct btrfs_workers *workers); +struct btrfs_workqueue *btrfs_alloc_workqueue(const char *name, + int flags, + int max_active, + int thresh) +{ + struct btrfs_workqueue *ret = kzalloc(sizeof(*ret), GFP_NOFS); -/* - * btrfs_start_workers uses kthread_run, which can block waiting for memory - * for a very long time. It will actually throttle on page writeback, - * and so it may not make progress until after our btrfs worker threads - * process all of the pending work structs in their queue - * - * This means we can't use btrfs_start_workers from inside a btrfs worker - * thread that is used as part of cleaning dirty memory, which pretty much - * involves all of the worker threads. - * - * Instead we have a helper queue who never has more than one thread - * where we scheduler thread start operations. This worker_start struct - * is used to contain the work and hold a pointer to the queue that needs - * another worker. - */ -struct worker_start { - struct btrfs_work work; - struct btrfs_workers *queue; -}; + if (unlikely(!ret)) + return NULL; -static void start_new_worker_func(struct btrfs_work *work) -{ - struct worker_start *start; - start = container_of(work, struct worker_start, work); - __btrfs_start_workers(start->queue); - kfree(start); -} + ret->normal = __btrfs_alloc_workqueue(name, flags & ~WQ_HIGHPRI, + max_active, thresh); + if (unlikely(!ret->normal)) { + kfree(ret); + return NULL; + } -/* - * helper function to move a thread onto the idle list after it - * has finished some requests. - */ -static void check_idle_worker(struct btrfs_worker_thread *worker) -{ - if (!worker->idle && atomic_read(&worker->num_pending) < - worker->workers->idle_thresh / 2) { - unsigned long flags; - spin_lock_irqsave(&worker->workers->lock, flags); - worker->idle = 1; - - /* the list may be empty if the worker is just starting */ - if (!list_empty(&worker->worker_list) && - !worker->workers->stopping) { - list_move(&worker->worker_list, - &worker->workers->idle_list); + if (flags & WQ_HIGHPRI) { + ret->high = __btrfs_alloc_workqueue(name, flags, max_active, + thresh); + if (unlikely(!ret->high)) { + __btrfs_destroy_workqueue(ret->normal); + kfree(ret); + return NULL; } - spin_unlock_irqrestore(&worker->workers->lock, flags); } + return ret; } /* - * helper function to move a thread off the idle list after new - * pending work is added. + * Hook for threshold which will be called in btrfs_queue_work. + * This hook WILL be called in IRQ handler context, + * so workqueue_set_max_active MUST NOT be called in this hook */ -static void check_busy_worker(struct btrfs_worker_thread *worker) +static inline void thresh_queue_hook(struct __btrfs_workqueue *wq) { - if (worker->idle && atomic_read(&worker->num_pending) >= - worker->workers->idle_thresh) { - unsigned long flags; - spin_lock_irqsave(&worker->workers->lock, flags); - worker->idle = 0; - - if (!list_empty(&worker->worker_list) && - !worker->workers->stopping) { - list_move_tail(&worker->worker_list, - &worker->workers->worker_list); - } - spin_unlock_irqrestore(&worker->workers->lock, flags); - } + if (wq->thresh == NO_THRESHOLD) + return; + atomic_inc(&wq->pending); } -static void check_pending_worker_creates(struct btrfs_worker_thread *worker) +/* + * Hook for threshold which will be called before executing the work, + * This hook is called in kthread content. + * So workqueue_set_max_active is called here. + */ +static inline void thresh_exec_hook(struct __btrfs_workqueue *wq) { - struct btrfs_workers *workers = worker->workers; - struct worker_start *start; - unsigned long flags; + int new_max_active; + long pending; + int need_change = 0; - rmb(); - if (!workers->atomic_start_pending) + if (wq->thresh == NO_THRESHOLD) return; - start = kzalloc(sizeof(*start), GFP_NOFS); - if (!start) - return; - - start->work.func = start_new_worker_func; - start->queue = workers; - - spin_lock_irqsave(&workers->lock, flags); - if (!workers->atomic_start_pending) - goto out; - - workers->atomic_start_pending = 0; - if (workers->num_workers + workers->num_workers_starting >= - workers->max_workers) - goto out; - - workers->num_workers_starting += 1; - spin_unlock_irqrestore(&workers->lock, flags); - btrfs_queue_worker(workers->atomic_worker_start, &start->work); - return; + atomic_dec(&wq->pending); + spin_lock(&wq->thres_lock); + /* + * Use wq->count to limit the calling frequency of + * workqueue_set_max_active. + */ + wq->count++; + wq->count %= (wq->thresh / 4); + if (!wq->count) + goto out; + new_max_active = wq->current_max; + /* + * pending may be changed later, but it's OK since we really + * don't need it so accurate to calculate new_max_active. + */ + pending = atomic_read(&wq->pending); + if (pending > wq->thresh) + new_max_active++; + if (pending < wq->thresh / 2) + new_max_active--; + new_max_active = clamp_val(new_max_active, 1, wq->max_active); + if (new_max_active != wq->current_max) { + need_change = 1; + wq->current_max = new_max_active; + } out: - kfree(start); - spin_unlock_irqrestore(&workers->lock, flags); + spin_unlock(&wq->thres_lock); + + if (need_change) { + workqueue_set_max_active(wq->normal_wq, wq->current_max); + } } -static noinline void run_ordered_completions(struct btrfs_workers *workers, - struct btrfs_work *work) +static void run_ordered_work(struct __btrfs_workqueue *wq) { - if (!workers->ordered) - return; - - set_bit(WORK_DONE_BIT, &work->flags); - - spin_lock(&workers->order_lock); + struct list_head *list = &wq->ordered_list; + struct btrfs_work *work; + spinlock_t *lock = &wq->list_lock; + unsigned long flags; while (1) { - if (!list_empty(&workers->prio_order_list)) { - work = list_entry(workers->prio_order_list.next, - struct btrfs_work, order_list); - } else if (!list_empty(&workers->order_list)) { - work = list_entry(workers->order_list.next, - struct btrfs_work, order_list); - } else { + spin_lock_irqsave(lock, flags); + if (list_empty(list)) break; - } + work = list_entry(list->next, struct btrfs_work, + ordered_list); if (!test_bit(WORK_DONE_BIT, &work->flags)) break; - /* we are going to call the ordered done function, but + /* + * we are going to call the ordered done function, but * we leave the work item on the list as a barrier so * that later work items that are done don't have their * functions called before this one returns */ if (test_and_set_bit(WORK_ORDER_DONE_BIT, &work->flags)) break; - - spin_unlock(&workers->order_lock); - + trace_btrfs_ordered_sched(work); + spin_unlock_irqrestore(lock, flags); work->ordered_func(work); /* now take the lock again and drop our item from the list */ - spin_lock(&workers->order_lock); - list_del(&work->order_list); - spin_unlock(&workers->order_lock); + spin_lock_irqsave(lock, flags); + list_del(&work->ordered_list); + spin_unlock_irqrestore(lock, flags); /* * we don't want to call the ordered free functions * with the lock held though */ work->ordered_free(work); - spin_lock(&workers->order_lock); - } - - spin_unlock(&workers->order_lock); -} - -static void put_worker(struct btrfs_worker_thread *worker) -{ - if (atomic_dec_and_test(&worker->refs)) - kfree(worker); -} - -static int try_worker_shutdown(struct btrfs_worker_thread *worker) -{ - int freeit = 0; - - spin_lock_irq(&worker->lock); - spin_lock(&worker->workers->lock); - if (worker->workers->num_workers > 1 && - worker->idle && - !worker->working && - !list_empty(&worker->worker_list) && - list_empty(&worker->prio_pending) && - list_empty(&worker->pending) && - atomic_read(&worker->num_pending) == 0) { - freeit = 1; - list_del_init(&worker->worker_list); - worker->workers->num_workers--; + trace_btrfs_all_work_done(work); } - spin_unlock(&worker->workers->lock); - spin_unlock_irq(&worker->lock); - - if (freeit) - put_worker(worker); - return freeit; + spin_unlock_irqrestore(lock, flags); } -static struct btrfs_work *get_next_work(struct btrfs_worker_thread *worker, - struct list_head *prio_head, - struct list_head *head) -{ - struct btrfs_work *work = NULL; - struct list_head *cur = NULL; - - if (!list_empty(prio_head)) - cur = prio_head->next; - - smp_mb(); - if (!list_empty(&worker->prio_pending)) - goto refill; - - if (!list_empty(head)) - cur = head->next; - - if (cur) - goto out; - -refill: - spin_lock_irq(&worker->lock); - list_splice_tail_init(&worker->prio_pending, prio_head); - list_splice_tail_init(&worker->pending, head); - - if (!list_empty(prio_head)) - cur = prio_head->next; - else if (!list_empty(head)) - cur = head->next; - spin_unlock_irq(&worker->lock); - - if (!cur) - goto out_fail; - -out: - work = list_entry(cur, struct btrfs_work, list); - -out_fail: - return work; -} - -/* - * main loop for servicing work items - */ -static int worker_loop(void *arg) +static void normal_work_helper(struct work_struct *arg) { - struct btrfs_worker_thread *worker = arg; - struct list_head head; - struct list_head prio_head; struct btrfs_work *work; + struct __btrfs_workqueue *wq; + int need_order = 0; - INIT_LIST_HEAD(&head); - INIT_LIST_HEAD(&prio_head); - - do { -again: - while (1) { - - - work = get_next_work(worker, &prio_head, &head); - if (!work) - break; - - list_del(&work->list); - clear_bit(WORK_QUEUED_BIT, &work->flags); - - work->worker = worker; - - work->func(work); - - atomic_dec(&worker->num_pending); - /* - * unless this is an ordered work queue, - * 'work' was probably freed by func above. - */ - run_ordered_completions(worker->workers, work); - - check_pending_worker_creates(worker); - cond_resched(); - } - - spin_lock_irq(&worker->lock); - check_idle_worker(worker); - - if (freezing(current)) { - worker->working = 0; - spin_unlock_irq(&worker->lock); - try_to_freeze(); - } else { - spin_unlock_irq(&worker->lock); - if (!kthread_should_stop()) { - cpu_relax(); - /* - * we've dropped the lock, did someone else - * jump_in? - */ - smp_mb(); - if (!list_empty(&worker->pending) || - !list_empty(&worker->prio_pending)) - continue; - - /* - * this short schedule allows more work to - * come in without the queue functions - * needing to go through wake_up_process() - * - * worker->working is still 1, so nobody - * is going to try and wake us up - */ - schedule_timeout(1); - smp_mb(); - if (!list_empty(&worker->pending) || - !list_empty(&worker->prio_pending)) - continue; - - if (kthread_should_stop()) - break; - - /* still no more work?, sleep for real */ - spin_lock_irq(&worker->lock); - set_current_state(TASK_INTERRUPTIBLE); - if (!list_empty(&worker->pending) || - !list_empty(&worker->prio_pending)) { - spin_unlock_irq(&worker->lock); - set_current_state(TASK_RUNNING); - goto again; - } - - /* - * this makes sure we get a wakeup when someone - * adds something new to the queue - */ - worker->working = 0; - spin_unlock_irq(&worker->lock); - - if (!kthread_should_stop()) { - schedule_timeout(HZ * 120); - if (!worker->working && - try_worker_shutdown(worker)) { - return 0; - } - } - } - __set_current_state(TASK_RUNNING); - } - } while (!kthread_should_stop()); - return 0; -} - -/* - * this will wait for all the worker threads to shutdown - */ -void btrfs_stop_workers(struct btrfs_workers *workers) -{ - struct list_head *cur; - struct btrfs_worker_thread *worker; - int can_stop; - - spin_lock_irq(&workers->lock); - workers->stopping = 1; - list_splice_init(&workers->idle_list, &workers->worker_list); - while (!list_empty(&workers->worker_list)) { - cur = workers->worker_list.next; - worker = list_entry(cur, struct btrfs_worker_thread, - worker_list); - - atomic_inc(&worker->refs); - workers->num_workers -= 1; - if (!list_empty(&worker->worker_list)) { - list_del_init(&worker->worker_list); - put_worker(worker); - can_stop = 1; - } else - can_stop = 0; - spin_unlock_irq(&workers->lock); - if (can_stop) - kthread_stop(worker->task); - spin_lock_irq(&workers->lock); - put_worker(worker); + work = container_of(arg, struct btrfs_work, normal_work); + /* + * We should not touch things inside work in the following cases: + * 1) after work->func() if it has no ordered_free + * Since the struct is freed in work->func(). + * 2) after setting WORK_DONE_BIT + * The work may be freed in other threads almost instantly. + * So we save the needed things here. + */ + if (work->ordered_func) + need_order = 1; + wq = work->wq; + + trace_btrfs_work_sched(work); + thresh_exec_hook(wq); + work->func(work); + if (need_order) { + set_bit(WORK_DONE_BIT, &work->flags); + run_ordered_work(wq); } - spin_unlock_irq(&workers->lock); + if (!need_order) + trace_btrfs_all_work_done(work); } -/* - * simple init on struct btrfs_workers - */ -void btrfs_init_workers(struct btrfs_workers *workers, char *name, int max, - struct btrfs_workers *async_helper) +void btrfs_init_work(struct btrfs_work *work, + btrfs_func_t func, + btrfs_func_t ordered_func, + btrfs_func_t ordered_free) { - workers->num_workers = 0; - workers->num_workers_starting = 0; - INIT_LIST_HEAD(&workers->worker_list); - INIT_LIST_HEAD(&workers->idle_list); - INIT_LIST_HEAD(&workers->order_list); - INIT_LIST_HEAD(&workers->prio_order_list); - spin_lock_init(&workers->lock); - spin_lock_init(&workers->order_lock); - workers->max_workers = max; - workers->idle_thresh = 32; - workers->name = name; - workers->ordered = 0; - workers->atomic_start_pending = 0; - workers->atomic_worker_start = async_helper; - workers->stopping = 0; + work->func = func; + work->ordered_func = ordered_func; + work->ordered_free = ordered_free; + INIT_WORK(&work->normal_work, normal_work_helper); + INIT_LIST_HEAD(&work->ordered_list); + work->flags = 0; } -/* - * starts new worker threads. This does not enforce the max worker - * count in case you need to temporarily go past it. - */ -static int __btrfs_start_workers(struct btrfs_workers *workers) +static inline void __btrfs_queue_work(struct __btrfs_workqueue *wq, + struct btrfs_work *work) { - struct btrfs_worker_thread *worker; - int ret = 0; - - worker = kzalloc(sizeof(*worker), GFP_NOFS); - if (!worker) { - ret = -ENOMEM; - goto fail; - } - - INIT_LIST_HEAD(&worker->pending); - INIT_LIST_HEAD(&worker->prio_pending); - INIT_LIST_HEAD(&worker->worker_list); - spin_lock_init(&worker->lock); - - atomic_set(&worker->num_pending, 0); - atomic_set(&worker->refs, 1); - worker->workers = workers; - worker->task = kthread_create(worker_loop, worker, - "btrfs-%s-%d", workers->name, - workers->num_workers + 1); - if (IS_ERR(worker->task)) { - ret = PTR_ERR(worker->task); - goto fail; - } + unsigned long flags; - spin_lock_irq(&workers->lock); - if (workers->stopping) { - spin_unlock_irq(&workers->lock); - ret = -EINVAL; - goto fail_kthread; + work->wq = wq; + thresh_queue_hook(wq); + if (work->ordered_func) { + spin_lock_irqsave(&wq->list_lock, flags); + list_add_tail(&work->ordered_list, &wq->ordered_list); + spin_unlock_irqrestore(&wq->list_lock, flags); } - list_add_tail(&worker->worker_list, &workers->idle_list); - worker->idle = 1; - workers->num_workers++; - workers->num_workers_starting--; - WARN_ON(workers->num_workers_starting < 0); - spin_unlock_irq(&workers->lock); - - wake_up_process(worker->task); - return 0; - -fail_kthread: - kthread_stop(worker->task); -fail: - kfree(worker); - spin_lock_irq(&workers->lock); - workers->num_workers_starting--; - spin_unlock_irq(&workers->lock); - return ret; + queue_work(wq->normal_wq, &work->normal_work); + trace_btrfs_work_queued(work); } -int btrfs_start_workers(struct btrfs_workers *workers) +void btrfs_queue_work(struct btrfs_workqueue *wq, + struct btrfs_work *work) { - spin_lock_irq(&workers->lock); - workers->num_workers_starting++; - spin_unlock_irq(&workers->lock); - return __btrfs_start_workers(workers); -} - -/* - * run through the list and find a worker thread that doesn't have a lot - * to do right now. This can return null if we aren't yet at the thread - * count limit and all of the threads are busy. - */ -static struct btrfs_worker_thread *next_worker(struct btrfs_workers *workers) -{ - struct btrfs_worker_thread *worker; - struct list_head *next; - int enforce_min; - - enforce_min = (workers->num_workers + workers->num_workers_starting) < - workers->max_workers; - - /* - * if we find an idle thread, don't move it to the end of the - * idle list. This improves the chance that the next submission - * will reuse the same thread, and maybe catch it while it is still - * working - */ - if (!list_empty(&workers->idle_list)) { - next = workers->idle_list.next; - worker = list_entry(next, struct btrfs_worker_thread, - worker_list); - return worker; - } - if (enforce_min || list_empty(&workers->worker_list)) - return NULL; - - /* - * if we pick a busy task, move the task to the end of the list. - * hopefully this will keep things somewhat evenly balanced. - * Do the move in batches based on the sequence number. This groups - * requests submitted at roughly the same time onto the same worker. - */ - next = workers->worker_list.next; - worker = list_entry(next, struct btrfs_worker_thread, worker_list); - worker->sequence++; + struct __btrfs_workqueue *dest_wq; - if (worker->sequence % workers->idle_thresh == 0) - list_move_tail(next, &workers->worker_list); - return worker; + if (test_bit(WORK_HIGH_PRIO_BIT, &work->flags) && wq->high) + dest_wq = wq->high; + else + dest_wq = wq->normal; + __btrfs_queue_work(dest_wq, work); } -/* - * selects a worker thread to take the next job. This will either find - * an idle worker, start a new worker up to the max count, or just return - * one of the existing busy workers. - */ -static struct btrfs_worker_thread *find_worker(struct btrfs_workers *workers) +static inline void +__btrfs_destroy_workqueue(struct __btrfs_workqueue *wq) { - struct btrfs_worker_thread *worker; - unsigned long flags; - struct list_head *fallback; - int ret; - - spin_lock_irqsave(&workers->lock, flags); -again: - worker = next_worker(workers); - - if (!worker) { - if (workers->num_workers + workers->num_workers_starting >= - workers->max_workers) { - goto fallback; - } else if (workers->atomic_worker_start) { - workers->atomic_start_pending = 1; - goto fallback; - } else { - workers->num_workers_starting++; - spin_unlock_irqrestore(&workers->lock, flags); - /* we're below the limit, start another worker */ - ret = __btrfs_start_workers(workers); - spin_lock_irqsave(&workers->lock, flags); - if (ret) - goto fallback; - goto again; - } - } - goto found; - -fallback: - fallback = NULL; - /* - * we have failed to find any workers, just - * return the first one we can find. - */ - if (!list_empty(&workers->worker_list)) - fallback = workers->worker_list.next; - if (!list_empty(&workers->idle_list)) - fallback = workers->idle_list.next; - BUG_ON(!fallback); - worker = list_entry(fallback, - struct btrfs_worker_thread, worker_list); -found: - /* - * this makes sure the worker doesn't exit before it is placed - * onto a busy/idle list - */ - atomic_inc(&worker->num_pending); - spin_unlock_irqrestore(&workers->lock, flags); - return worker; + destroy_workqueue(wq->normal_wq); + trace_btrfs_workqueue_destroy(wq); + kfree(wq); } -/* - * btrfs_requeue_work just puts the work item back on the tail of the list - * it was taken from. It is intended for use with long running work functions - * that make some progress and want to give the cpu up for others. - */ -void btrfs_requeue_work(struct btrfs_work *work) +void btrfs_destroy_workqueue(struct btrfs_workqueue *wq) { - struct btrfs_worker_thread *worker = work->worker; - unsigned long flags; - int wake = 0; - - if (test_and_set_bit(WORK_QUEUED_BIT, &work->flags)) + if (!wq) return; - - spin_lock_irqsave(&worker->lock, flags); - if (test_bit(WORK_HIGH_PRIO_BIT, &work->flags)) - list_add_tail(&work->list, &worker->prio_pending); - else - list_add_tail(&work->list, &worker->pending); - atomic_inc(&worker->num_pending); - - /* by definition we're busy, take ourselves off the idle - * list - */ - if (worker->idle) { - spin_lock(&worker->workers->lock); - worker->idle = 0; - list_move_tail(&worker->worker_list, - &worker->workers->worker_list); - spin_unlock(&worker->workers->lock); - } - if (!worker->working) { - wake = 1; - worker->working = 1; - } - - if (wake) - wake_up_process(worker->task); - spin_unlock_irqrestore(&worker->lock, flags); + if (wq->high) + __btrfs_destroy_workqueue(wq->high); + __btrfs_destroy_workqueue(wq->normal); + kfree(wq); } -void btrfs_set_work_high_prio(struct btrfs_work *work) +void btrfs_workqueue_set_max(struct btrfs_workqueue *wq, int max) { - set_bit(WORK_HIGH_PRIO_BIT, &work->flags); + wq->normal->max_active = max; + if (wq->high) + wq->high->max_active = max; } -/* - * places a struct btrfs_work into the pending queue of one of the kthreads - */ -void btrfs_queue_worker(struct btrfs_workers *workers, struct btrfs_work *work) +void btrfs_set_work_high_priority(struct btrfs_work *work) { - struct btrfs_worker_thread *worker; - unsigned long flags; - int wake = 0; - - /* don't requeue something already on a list */ - if (test_and_set_bit(WORK_QUEUED_BIT, &work->flags)) - return; - - worker = find_worker(workers); - if (workers->ordered) { - /* - * you're not allowed to do ordered queues from an - * interrupt handler - */ - spin_lock(&workers->order_lock); - if (test_bit(WORK_HIGH_PRIO_BIT, &work->flags)) { - list_add_tail(&work->order_list, - &workers->prio_order_list); - } else { - list_add_tail(&work->order_list, &workers->order_list); - } - spin_unlock(&workers->order_lock); - } else { - INIT_LIST_HEAD(&work->order_list); - } - - spin_lock_irqsave(&worker->lock, flags); - - if (test_bit(WORK_HIGH_PRIO_BIT, &work->flags)) - list_add_tail(&work->list, &worker->prio_pending); - else - list_add_tail(&work->list, &worker->pending); - check_busy_worker(worker); - - /* - * avoid calling into wake_up_process if this thread has already - * been kicked - */ - if (!worker->working) - wake = 1; - worker->working = 1; - - if (wake) - wake_up_process(worker->task); - spin_unlock_irqrestore(&worker->lock, flags); + set_bit(WORK_HIGH_PRIO_BIT, &work->flags); } |