From 6c71013ecb7e2bddbed9f5b95e7aed22c491daa9 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Thu, 16 Jul 2015 11:16:45 +0800 Subject: block: partition: convert percpu ref Percpu refcount is the perfect match for partition's case, and the conversion is quite straight. With the convertion, one pair of atomic inc/dec can be saved for accounting block I/O, which is run in hot path of block I/O. Signed-off-by: Ming Lei Acked-by: Tejun Heo Signed-off-by: Jens Axboe --- block/partition-generic.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'block/partition-generic.c') diff --git a/block/partition-generic.c b/block/partition-generic.c index eca0d02a607c2..e7711133284e1 100644 --- a/block/partition-generic.c +++ b/block/partition-generic.c @@ -232,8 +232,9 @@ static void delete_partition_rcu_cb(struct rcu_head *head) put_device(part_to_dev(part)); } -void __delete_partition(struct hd_struct *part) +void __delete_partition(struct percpu_ref *ref) { + struct hd_struct *part = container_of(ref, struct hd_struct, ref); call_rcu(&part->rcu_head, delete_partition_rcu_cb); } @@ -254,7 +255,7 @@ void delete_partition(struct gendisk *disk, int partno) kobject_put(part->holder_dir); device_del(part_to_dev(part)); - hd_struct_put(part); + hd_struct_kill(part); } static ssize_t whole_disk_show(struct device *dev, @@ -355,8 +356,8 @@ struct hd_struct *add_partition(struct gendisk *disk, int partno, if (!dev_get_uevent_suppress(ddev)) kobject_uevent(&pdev->kobj, KOBJ_ADD); - hd_ref_init(p); - return p; + if (!hd_ref_init(p)) + return p; out_free_info: free_part_info(p); -- cgit v1.2.3