}
rb_link_node(&crq->rb_node, parent, p);
- return 0;
+ return NULL;
}
static void
mempool_free(cfqq, cfq_mpool);
}
-static struct cfq_queue *cfq_get_queue(struct cfq_data *cfqd, int pid)
+static struct cfq_queue *__cfq_get_queue(struct cfq_data *cfqd, int pid,
+ int gfp_mask)
{
const int hashval = hash_long(current->tgid, CFQ_QHASH_SHIFT);
- struct cfq_queue *cfqq = __cfq_find_cfq_hash(cfqd, pid, hashval);
+ struct cfq_queue *cfqq, *new_cfqq = NULL;
+ request_queue_t *q = cfqd->queue;
+
+retry:
+ cfqq = __cfq_find_cfq_hash(cfqd, pid, hashval);
if (!cfqq) {
- cfqq = mempool_alloc(cfq_mpool, GFP_NOIO);
+ if (new_cfqq) {
+ cfqq = new_cfqq;
+ new_cfqq = NULL;
+ } else if (gfp_mask & __GFP_WAIT) {
+ spin_unlock_irq(q->queue_lock);
+ new_cfqq = mempool_alloc(cfq_mpool, gfp_mask);
+ spin_lock_irq(q->queue_lock);
+ goto retry;
+ } else
+ return NULL;
INIT_LIST_HEAD(&cfqq->cfq_hash);
INIT_LIST_HEAD(&cfqq->cfq_list);
list_add(&cfqq->cfq_hash, &cfqd->cfq_hash[hashval]);
}
+ if (new_cfqq)
+ mempool_free(new_cfqq, cfq_mpool);
+
return cfqq;
}
-static void cfq_enqueue(struct cfq_data *cfqd, struct cfq_rq *crq)
+static struct cfq_queue *cfq_get_queue(struct cfq_data *cfqd, int pid,
+ int gfp_mask)
{
+ request_queue_t *q = cfqd->queue;
struct cfq_queue *cfqq;
- cfqq = cfq_get_queue(cfqd, current->tgid);
+ spin_lock_irq(q->queue_lock);
+ cfqq = __cfq_get_queue(cfqd, pid, gfp_mask);
+ spin_unlock_irq(q->queue_lock);
+
+ return cfqq;
+}
+
+static void cfq_enqueue(struct cfq_data *cfqd, struct cfq_rq *crq)
+{
+ struct cfq_queue *cfqq;
- cfq_add_crq_rb(cfqd, cfqq, crq);
+ cfqq = __cfq_get_queue(cfqd, current->tgid, GFP_ATOMIC);
+ if (cfqq) {
+ cfq_add_crq_rb(cfqd, cfqq, crq);
- if (list_empty(&cfqq->cfq_list)) {
- list_add(&cfqq->cfq_list, &cfqd->rr_list);
- cfqd->busy_queues++;
+ if (list_empty(&cfqq->cfq_list)) {
+ list_add(&cfqq->cfq_list, &cfqd->rr_list);
+ cfqd->busy_queues++;
+ }
+ } else {
+ /*
+ * should can only happen if the request wasn't allocated
+ * through blk_alloc_request(), eg stack requests from ide-cd
+ * (those should be removed) _and_ we are in OOM.
+ */
+ list_add_tail(&crq->request->queuelist, cfqd->dispatch);
}
}
static int cfq_set_request(request_queue_t *q, struct request *rq, int gfp_mask)
{
struct cfq_data *cfqd = q->elevator.elevator_data;
- struct cfq_rq *crq = mempool_alloc(cfqd->crq_pool, gfp_mask);
+ struct cfq_queue *cfqq;
+ struct cfq_rq *crq;
+
+ /*
+ * prepare a queue up front, so cfq_enqueue() doesn't have to
+ */
+ cfqq = cfq_get_queue(cfqd, current->tgid, gfp_mask);
+ if (!cfqq)
+ return 1;
+ crq = mempool_alloc(cfqd->crq_pool, gfp_mask);
if (crq) {
+ memset(crq, 0, sizeof(*crq));
RB_CLEAR(&crq->rb_node);
crq->request = rq;
crq->cfq_queue = NULL;