From 24afc15dbe218f860994f627b4ba1fb09225a298 Mon Sep 17 00:00:00 2001 From: Christophe JAILLET Date: Mon, 7 Feb 2022 21:48:19 +0100 Subject: [PATCH] block/rnbd: Remove a useless mutex According to lib/idr.c, The IDA handles its own locking. It is safe to call any of the IDA functions without synchronisation in your code. so the 'ida_lock' mutex can just be removed. It is here only to protect some ida_simple_get()/ida_simple_remove() calls. While at it, switch to ida_alloc_XXX()/ida_free() instead to ida_simple_get()/ida_simple_remove(). The latter is deprecated and more verbose. Signed-off-by: Christophe JAILLET Acked-by: Jack Wang Link: https://lore.kernel.org/r/7f9eccd8b1fce1bac45ac9b01a78cf72f54c0a61.1644266862.git.christophe.jaillet@wanadoo.fr Signed-off-by: Jens Axboe --- drivers/block/rnbd/rnbd-clt.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c index 9a880d5..1f63f30 100644 --- a/drivers/block/rnbd/rnbd-clt.c +++ b/drivers/block/rnbd/rnbd-clt.c @@ -23,7 +23,6 @@ MODULE_LICENSE("GPL"); static int rnbd_client_major; static DEFINE_IDA(index_ida); -static DEFINE_MUTEX(ida_lock); static DEFINE_MUTEX(sess_lock); static LIST_HEAD(sess_list); @@ -55,9 +54,7 @@ static void rnbd_clt_put_dev(struct rnbd_clt_dev *dev) if (!refcount_dec_and_test(&dev->refcount)) return; - mutex_lock(&ida_lock); - ida_simple_remove(&index_ida, dev->clt_device_id); - mutex_unlock(&ida_lock); + ida_free(&index_ida, dev->clt_device_id); kfree(dev->hw_queues); kfree(dev->pathname); rnbd_clt_put_sess(dev->sess); @@ -1460,10 +1457,8 @@ static struct rnbd_clt_dev *init_dev(struct rnbd_clt_session *sess, goto out_alloc; } - mutex_lock(&ida_lock); - ret = ida_simple_get(&index_ida, 0, 1 << (MINORBITS - RNBD_PART_BITS), - GFP_KERNEL); - mutex_unlock(&ida_lock); + ret = ida_alloc_max(&index_ida, 1 << (MINORBITS - RNBD_PART_BITS), + GFP_KERNEL); if (ret < 0) { pr_err("Failed to initialize device '%s' from session %s, allocating idr failed, err: %d\n", pathname, sess->sessname, ret); -- 2.7.4