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block, bfq: do not idle if only one group is activated

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Now that root group is counted into 'num_groups_with_pending_reqs',
'num_groups_with_pending_reqs > 0' is always true in
bfq_asymmetric_scenario(). Thus change the condition to '> 1'.

On the other hand, this change can enable concurrent sync io if only
one group is activated.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20220916071942.214222-5-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Yu Kuai 2022-09-16 15:19:40 +08:00 committed by Jens Axboe
parent 71f8ca77cb
commit eed3ecc991
1 changed files with 2 additions and 2 deletions
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block/bfq-iosched.c
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@ -820,7 +820,7 @@ bfq_pos_tree_add_move(struct bfq_data *bfqd, struct bfq_queue *bfqq)
* much easier to maintain the needed state:
* 1) all active queues have the same weight,
* 2) all active queues belong to the same I/O-priority class,
* 3) there are no active groups.
* 3) there is at most one active group.
* In particular, the last condition is always true if hierarchical
* support or the cgroups interface are not enabled, thus no state
* needs to be maintained in this case.
@ -852,7 +852,7 @@ static bool bfq_asymmetric_scenario(struct bfq_data *bfqd,
return varied_queue_weights || multiple_classes_busy
#ifdef CONFIG_BFQ_GROUP_IOSCHED
|| bfqd->num_groups_with_pending_reqs > 0
|| bfqd->num_groups_with_pending_reqs > 1
#endif
;
}