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authorChris Mason <chris.mason@oracle.com>2011-12-15 13:43:49 -0500
committerChris Mason <chris.mason@oracle.com>2011-12-15 13:43:49 -0500
commit567a45e917343c952806bb9f5c19aab0139bd519 (patch)
treeb1d6dac31a3a2836d24662139f21bb1ddc2522d3 /fs/btrfs/async-thread.c
parente755d9ab387c4c2401dce5b6f435432a829f41cb (diff)
parente65cbb94e036058128a5dec6398be2fd64cf88ba (diff)
Merge branch 'for-chris' of http://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-work into integration
Conflicts: fs/btrfs/inode.c Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs/btrfs/async-thread.c')
-rw-r--r--fs/btrfs/async-thread.c115
1 files changed, 54 insertions, 61 deletions
diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c
index 203e849dc9c9..cb97174e2366 100644
--- a/fs/btrfs/async-thread.c
+++ b/fs/btrfs/async-thread.c
@@ -64,6 +64,8 @@ struct btrfs_worker_thread {
64 int idle; 64 int idle;
65}; 65};
66 66
67static int __btrfs_start_workers(struct btrfs_workers *workers);
68
67/* 69/*
68 * btrfs_start_workers uses kthread_run, which can block waiting for memory 70 * btrfs_start_workers uses kthread_run, which can block waiting for memory
69 * for a very long time. It will actually throttle on page writeback, 71 * for a very long time. It will actually throttle on page writeback,
@@ -88,27 +90,10 @@ static void start_new_worker_func(struct btrfs_work *work)
88{ 90{
89 struct worker_start *start; 91 struct worker_start *start;
90 start = container_of(work, struct worker_start, work); 92 start = container_of(work, struct worker_start, work);
91 btrfs_start_workers(start->queue, 1); 93 __btrfs_start_workers(start->queue);
92 kfree(start); 94 kfree(start);
93} 95}
94 96
95static int start_new_worker(struct btrfs_workers *queue)
96{
97 struct worker_start *start;
98 int ret;
99
100 start = kzalloc(sizeof(*start), GFP_NOFS);
101 if (!start)
102 return -ENOMEM;
103
104 start->work.func = start_new_worker_func;
105 start->queue = queue;
106 ret = btrfs_queue_worker(queue->atomic_worker_start, &start->work);
107 if (ret)
108 kfree(start);
109 return ret;
110}
111
112/* 97/*
113 * helper function to move a thread onto the idle list after it 98 * helper function to move a thread onto the idle list after it
114 * has finished some requests. 99 * has finished some requests.
@@ -153,12 +138,20 @@ static void check_busy_worker(struct btrfs_worker_thread *worker)
153static void check_pending_worker_creates(struct btrfs_worker_thread *worker) 138static void check_pending_worker_creates(struct btrfs_worker_thread *worker)
154{ 139{
155 struct btrfs_workers *workers = worker->workers; 140 struct btrfs_workers *workers = worker->workers;
141 struct worker_start *start;
156 unsigned long flags; 142 unsigned long flags;
157 143
158 rmb(); 144 rmb();
159 if (!workers->atomic_start_pending) 145 if (!workers->atomic_start_pending)
160 return; 146 return;
161 147
148 start = kzalloc(sizeof(*start), GFP_NOFS);
149 if (!start)
150 return;
151
152 start->work.func = start_new_worker_func;
153 start->queue = workers;
154
162 spin_lock_irqsave(&workers->lock, flags); 155 spin_lock_irqsave(&workers->lock, flags);
163 if (!workers->atomic_start_pending) 156 if (!workers->atomic_start_pending)
164 goto out; 157 goto out;
@@ -170,10 +163,11 @@ static void check_pending_worker_creates(struct btrfs_worker_thread *worker)
170 163
171 workers->num_workers_starting += 1; 164 workers->num_workers_starting += 1;
172 spin_unlock_irqrestore(&workers->lock, flags); 165 spin_unlock_irqrestore(&workers->lock, flags);
173 start_new_worker(workers); 166 btrfs_queue_worker(workers->atomic_worker_start, &start->work);
174 return; 167 return;
175 168
176out: 169out:
170 kfree(start);
177 spin_unlock_irqrestore(&workers->lock, flags); 171 spin_unlock_irqrestore(&workers->lock, flags);
178} 172}
179 173
@@ -462,56 +456,55 @@ void btrfs_init_workers(struct btrfs_workers *workers, char *name, int max,
462 * starts new worker threads. This does not enforce the max worker 456 * starts new worker threads. This does not enforce the max worker
463 * count in case you need to temporarily go past it. 457 * count in case you need to temporarily go past it.
464 */ 458 */
465static int __btrfs_start_workers(struct btrfs_workers *workers, 459static int __btrfs_start_workers(struct btrfs_workers *workers)
466 int num_workers)
467{ 460{
468 struct btrfs_worker_thread *worker; 461 struct btrfs_worker_thread *worker;
469 int ret = 0; 462 int ret = 0;
470 int i;
471 463
472 for (i = 0; i < num_workers; i++) { 464 worker = kzalloc(sizeof(*worker), GFP_NOFS);
473 worker = kzalloc(sizeof(*worker), GFP_NOFS); 465 if (!worker) {
474 if (!worker) { 466 ret = -ENOMEM;
475 ret = -ENOMEM; 467 goto fail;
476 goto fail; 468 }
477 }
478 469
479 INIT_LIST_HEAD(&worker->pending); 470 INIT_LIST_HEAD(&worker->pending);
480 INIT_LIST_HEAD(&worker->prio_pending); 471 INIT_LIST_HEAD(&worker->prio_pending);
481 INIT_LIST_HEAD(&worker->worker_list); 472 INIT_LIST_HEAD(&worker->worker_list);
482 spin_lock_init(&worker->lock); 473 spin_lock_init(&worker->lock);
483 474
484 atomic_set(&worker->num_pending, 0); 475 atomic_set(&worker->num_pending, 0);
485 atomic_set(&worker->refs, 1); 476 atomic_set(&worker->refs, 1);
486 worker->workers = workers; 477 worker->workers = workers;
487 worker->task = kthread_run(worker_loop, worker, 478 worker->task = kthread_run(worker_loop, worker,
488 "btrfs-%s-%d", workers->name, 479 "btrfs-%s-%d", workers->name,
489 workers->num_workers + i); 480 workers->num_workers + 1);
490 if (IS_ERR(worker->task)) { 481 if (IS_ERR(worker->task)) {
491 ret = PTR_ERR(worker->task); 482 ret = PTR_ERR(worker->task);
492 kfree(worker); 483 kfree(worker);
493 goto fail; 484 goto fail;
494 }
495 spin_lock_irq(&workers->lock);
496 list_add_tail(&worker->worker_list, &workers->idle_list);
497 worker->idle = 1;
498 workers->num_workers++;
499 workers->num_workers_starting--;
500 WARN_ON(workers->num_workers_starting < 0);
501 spin_unlock_irq(&workers->lock);
502 } 485 }
486 spin_lock_irq(&workers->lock);
487 list_add_tail(&worker->worker_list, &workers->idle_list);
488 worker->idle = 1;
489 workers->num_workers++;
490 workers->num_workers_starting--;
491 WARN_ON(workers->num_workers_starting < 0);
492 spin_unlock_irq(&workers->lock);
493
503 return 0; 494 return 0;
504fail: 495fail:
505 btrfs_stop_workers(workers); 496 spin_lock_irq(&workers->lock);
497 workers->num_workers_starting--;
498 spin_unlock_irq(&workers->lock);
506 return ret; 499 return ret;
507} 500}
508 501
509int btrfs_start_workers(struct btrfs_workers *workers, int num_workers) 502int btrfs_start_workers(struct btrfs_workers *workers)
510{ 503{
511 spin_lock_irq(&workers->lock); 504 spin_lock_irq(&workers->lock);
512 workers->num_workers_starting += num_workers; 505 workers->num_workers_starting++;
513 spin_unlock_irq(&workers->lock); 506 spin_unlock_irq(&workers->lock);
514 return __btrfs_start_workers(workers, num_workers); 507 return __btrfs_start_workers(workers);
515} 508}
516 509
517/* 510/*
@@ -568,6 +561,7 @@ static struct btrfs_worker_thread *find_worker(struct btrfs_workers *workers)
568 struct btrfs_worker_thread *worker; 561 struct btrfs_worker_thread *worker;
569 unsigned long flags; 562 unsigned long flags;
570 struct list_head *fallback; 563 struct list_head *fallback;
564 int ret;
571 565
572again: 566again:
573 spin_lock_irqsave(&workers->lock, flags); 567 spin_lock_irqsave(&workers->lock, flags);
@@ -584,7 +578,9 @@ again:
584 workers->num_workers_starting++; 578 workers->num_workers_starting++;
585 spin_unlock_irqrestore(&workers->lock, flags); 579 spin_unlock_irqrestore(&workers->lock, flags);
586 /* we're below the limit, start another worker */ 580 /* we're below the limit, start another worker */
587 __btrfs_start_workers(workers, 1); 581 ret = __btrfs_start_workers(workers);
582 if (ret)
583 goto fallback;
588 goto again; 584 goto again;
589 } 585 }
590 } 586 }
@@ -665,7 +661,7 @@ void btrfs_set_work_high_prio(struct btrfs_work *work)
665/* 661/*
666 * places a struct btrfs_work into the pending queue of one of the kthreads 662 * places a struct btrfs_work into the pending queue of one of the kthreads
667 */ 663 */
668int btrfs_queue_worker(struct btrfs_workers *workers, struct btrfs_work *work) 664void btrfs_queue_worker(struct btrfs_workers *workers, struct btrfs_work *work)
669{ 665{
670 struct btrfs_worker_thread *worker; 666 struct btrfs_worker_thread *worker;
671 unsigned long flags; 667 unsigned long flags;
@@ -673,7 +669,7 @@ int btrfs_queue_worker(struct btrfs_workers *workers, struct btrfs_work *work)
673 669
674 /* don't requeue something already on a list */ 670 /* don't requeue something already on a list */
675 if (test_and_set_bit(WORK_QUEUED_BIT, &work->flags)) 671 if (test_and_set_bit(WORK_QUEUED_BIT, &work->flags))
676 goto out; 672 return;
677 673
678 worker = find_worker(workers); 674 worker = find_worker(workers);
679 if (workers->ordered) { 675 if (workers->ordered) {
@@ -712,7 +708,4 @@ int btrfs_queue_worker(struct btrfs_workers *workers, struct btrfs_work *work)
712 if (wake) 708 if (wake)
713 wake_up_process(worker->task); 709 wake_up_process(worker->task);
714 spin_unlock_irqrestore(&worker->lock, flags); 710 spin_unlock_irqrestore(&worker->lock, flags);
715
716out:
717 return 0;
718} 711}