From: Matthew Wilcox <mawil...@microsoft.com> Skip converting the lock to use xa_lock; I think this code can live with the double-locking.
Signed-off-by: Matthew Wilcox <mawil...@microsoft.com> --- block/blk-ioc.c | 13 +++++++------ include/linux/iocontext.h | 6 +++--- 2 files changed, 10 insertions(+), 9 deletions(-) diff --git a/block/blk-ioc.c b/block/blk-ioc.c index f23311e4b201..baf83c8ac503 100644 --- a/block/blk-ioc.c +++ b/block/blk-ioc.c @@ -68,7 +68,7 @@ static void ioc_destroy_icq(struct io_cq *icq) lockdep_assert_held(&ioc->lock); - radix_tree_delete(&ioc->icq_tree, icq->q->id); + xa_erase(&ioc->icq_array, icq->q->id); hlist_del_init(&icq->ioc_node); list_del_init(&icq->q_node); @@ -278,7 +278,7 @@ int create_task_io_context(struct task_struct *task, gfp_t gfp_flags, int node) atomic_set(&ioc->nr_tasks, 1); atomic_set(&ioc->active_ref, 1); spin_lock_init(&ioc->lock); - INIT_RADIX_TREE(&ioc->icq_tree, GFP_ATOMIC | __GFP_HIGH); + xa_init_flags(&ioc->icq_array, XA_FLAGS_LOCK_IRQ); INIT_HLIST_HEAD(&ioc->icq_list); INIT_WORK(&ioc->release_work, ioc_release_fn); @@ -363,7 +363,7 @@ struct io_cq *ioc_lookup_icq(struct io_context *ioc, struct request_queue *q) if (icq && icq->q == q) goto out; - icq = radix_tree_lookup(&ioc->icq_tree, q->id); + icq = xa_load(&ioc->icq_array, q->id); if (icq && icq->q == q) rcu_assign_pointer(ioc->icq_hint, icq); /* allowed to race */ else @@ -398,7 +398,7 @@ struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q, if (!icq) return NULL; - if (radix_tree_maybe_preload(gfp_mask) < 0) { + if (xa_reserve(&ioc->icq_array, q->id, gfp_mask)) { kmem_cache_free(et->icq_cache, icq); return NULL; } @@ -412,7 +412,8 @@ struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q, spin_lock_irq(q->queue_lock); spin_lock(&ioc->lock); - if (likely(!radix_tree_insert(&ioc->icq_tree, q->id, icq))) { + if (likely(!xa_store(&ioc->icq_array, q->id, icq, + GFP_ATOMIC | __GFP_HIGH))) { hlist_add_head(&icq->ioc_node, &ioc->icq_list); list_add(&icq->q_node, &q->icq_list); if (et->uses_mq && et->ops.mq.init_icq) @@ -421,6 +422,7 @@ struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q, et->ops.sq.elevator_init_icq_fn(icq); } else { kmem_cache_free(et->icq_cache, icq); + xa_erase(&ioc->icq_array, q->id); icq = ioc_lookup_icq(ioc, q); if (!icq) printk(KERN_ERR "cfq: icq link failed!\n"); @@ -428,7 +430,6 @@ struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q, spin_unlock(&ioc->lock); spin_unlock_irq(q->queue_lock); - radix_tree_preload_end(); return icq; } diff --git a/include/linux/iocontext.h b/include/linux/iocontext.h index dba15ca8e60b..e16224f70084 100644 --- a/include/linux/iocontext.h +++ b/include/linux/iocontext.h @@ -2,9 +2,9 @@ #ifndef IOCONTEXT_H #define IOCONTEXT_H -#include <linux/radix-tree.h> #include <linux/rcupdate.h> #include <linux/workqueue.h> +#include <linux/xarray.h> enum { ICQ_EXITED = 1 << 2, @@ -56,7 +56,7 @@ enum { * - ioc->icq_list and icq->ioc_node are protected by ioc lock. * q->icq_list and icq->q_node by q lock. * - * - ioc->icq_tree and ioc->icq_hint are protected by ioc lock, while icq + * - ioc->icq_array and ioc->icq_hint are protected by ioc lock, while icq * itself is protected by q lock. However, both the indexes and icq * itself are also RCU managed and lookup can be performed holding only * the q lock. @@ -111,7 +111,7 @@ struct io_context { int nr_batch_requests; /* Number of requests left in the batch */ unsigned long last_waited; /* Time last woken after wait for request */ - struct radix_tree_root icq_tree; + struct xarray icq_array; struct io_cq __rcu *icq_hint; struct hlist_head icq_list; -- 2.15.1