X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=block%2Fll_rw_blk.c;h=7eb36c53f4b7868247141a105ef82e8be3e2d96f;hb=5b542e4422766d644ca303b8a47b27ec9eeeef3a;hp=cb608768ca37f5ba0a8ee694e5c0007547b6c00c;hpb=e2d74ac0664c89757bde8fb18c98cd7bf53da61c;p=linux-2.6 diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index cb608768ca..7eb36c53f4 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -1554,7 +1554,7 @@ void blk_plug_device(request_queue_t *q) * don't plug a stopped queue, it must be paired with blk_start_queue() * which will restart the queueing */ - if (test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags)) + if (blk_queue_stopped(q)) return; if (!test_and_set_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags)) { @@ -1587,7 +1587,7 @@ EXPORT_SYMBOL(blk_remove_plug); */ void __generic_unplug_device(request_queue_t *q) { - if (unlikely(test_bit(QUEUE_FLAG_STOPPED, &q->queue_flags))) + if (unlikely(blk_queue_stopped(q))) return; if (!blk_remove_plug(q)) @@ -1732,15 +1732,28 @@ void blk_run_queue(struct request_queue *q) spin_lock_irqsave(q->queue_lock, flags); blk_remove_plug(q); - if (!elv_queue_empty(q)) - q->request_fn(q); + + /* + * Only recurse once to avoid overrunning the stack, let the unplug + * handling reinvoke the handler shortly if we already got there. + */ + if (!elv_queue_empty(q)) { + if (!test_and_set_bit(QUEUE_FLAG_REENTER, &q->queue_flags)) { + q->request_fn(q); + clear_bit(QUEUE_FLAG_REENTER, &q->queue_flags); + } else { + blk_plug_device(q); + kblockd_schedule_work(&q->unplug_work); + } + } + spin_unlock_irqrestore(q->queue_lock, flags); } EXPORT_SYMBOL(blk_run_queue); /** * blk_cleanup_queue: - release a &request_queue_t when it is no longer needed - * @q: the request queue to be released + * @kobj: the kobj belonging of the request queue to be released * * Description: * blk_cleanup_queue is the pair to blk_init_queue() or @@ -3385,7 +3398,7 @@ static int blk_cpu_notify(struct notifier_block *self, unsigned long action, } -static struct notifier_block __devinitdata blk_cpu_notifier = { +static struct notifier_block blk_cpu_notifier = { .notifier_call = blk_cpu_notify, }; @@ -3439,7 +3452,12 @@ void end_that_request_last(struct request *req, int uptodate) if (unlikely(laptop_mode) && blk_fs_request(req)) laptop_io_completion(); - if (disk && blk_fs_request(req)) { + /* + * Account IO completion. bar_rq isn't accounted as a normal + * IO on queueing nor completion. Accounting the containing + * request is enough. + */ + if (disk && blk_fs_request(req) && req != &req->q->bar_rq) { unsigned long duration = jiffies - req->start_time; const int rw = rq_data_dir(req); @@ -3514,7 +3532,7 @@ int __init blk_dev_init(void) iocontext_cachep = kmem_cache_create("blkdev_ioc", sizeof(struct io_context), 0, SLAB_PANIC, NULL, NULL); - for_each_cpu(i) + for_each_possible_cpu(i) INIT_LIST_HEAD(&per_cpu(blk_cpu_done, i)); open_softirq(BLOCK_SOFTIRQ, blk_done_softirq, NULL); @@ -3545,7 +3563,9 @@ void put_io_context(struct io_context *ioc) if (ioc->aic && ioc->aic->dtor) ioc->aic->dtor(ioc->aic); if (ioc->cic_root.rb_node != NULL) { - cic = rb_entry(rb_first(&ioc->cic_root), struct cfq_io_context, rb_node); + struct rb_node *n = rb_first(&ioc->cic_root); + + cic = rb_entry(n, struct cfq_io_context, rb_node); cic->dtor(ioc); } rcu_read_unlock();