From 4a3b666e0ea977dd40adb56c37a91370f76fa19e Mon Sep 17 00:00:00 2001 From: Jakob Koschel Date: Thu, 31 Mar 2022 11:12:18 +0200 Subject: [PATCH] block: use dedicated list iterator variable To move the list iterator variable into the list_for_each_entry_*() macro in the future it should be avoided to use the list iterator variable after the loop body. To *never* use the list iterator variable after the loop it was concluded to use a separate iterator variable instead of a found boolean [1]. Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1] Signed-off-by: Jakob Koschel Link: https://lore.kernel.org/r/20220331091218.641532-1-jakobkoschel@gmail.com [axboe: move lookup to where return value is checked] Signed-off-by: Jens Axboe --- block/blk-mq.c | 25 ++++++++++++++++--------- 1 file changed, 16 insertions(+), 9 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 213bb5979bed..176b031510ff 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -4448,21 +4448,28 @@ static bool blk_mq_elv_switch_none(struct list_head *head, return true; } -static void blk_mq_elv_switch_back(struct list_head *head, - struct request_queue *q) +static struct blk_mq_qe_pair *blk_lookup_qe_pair(struct list_head *head, + struct request_queue *q) { struct blk_mq_qe_pair *qe; - struct elevator_type *t = NULL; list_for_each_entry(qe, head, node) - if (qe->q == q) { - t = qe->type; - break; - } + if (qe->q == q) + return qe; - if (!t) + return NULL; +} + +static void blk_mq_elv_switch_back(struct list_head *head, + struct request_queue *q) +{ + struct blk_mq_qe_pair *qe; + struct elevator_type *t; + + qe = blk_lookup_qe_pair(head, q); + if (!qe) return; - + t = qe->type; list_del(&qe->node); kfree(qe);