diff options
| author | Yu Kuai <yukuai3@huawei.com> | 2023-05-27 04:06:43 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2023-06-26 18:53:36 +0300 |
| commit | eebc21d12f56c1e09a163abf91e351fa2a55a938 (patch) | |
| tree | 31b8644fe6536bd0d886911844505c91abf68bb4 /block | |
| parent | 06257fda83ebfd1c33fb992e41dba7be4e1184d4 (diff) | |
| download | linux-eebc21d12f56c1e09a163abf91e351fa2a55a938.tar.xz | |
blk-iocost: move wbt_enable/disable_default() out of spinlock
There are following smatch warning:
block/blk-wbt.c:843 wbt_init() warn: sleeping in atomic context
ioc_qos_write() <- disables preempt
-> wbt_enable_default()
-> wbt_init()
wbt_init() will be called from wbt_enable_default() if wbt is not
initialized, currently this is only possible in blk_register_queue(), hence
wbt_init() will never be called from iocost and this warning is false
positive.
However, we might support rq_qos destruction dynamically in the future,
and it's better to prevent that, hence move wbt_enable_default() outside
'ioc->lock'. This is safe because queue is still freezed.
Reported-by: Dan Carpenter <error27@gmail.com>
Link: https://lore.kernel.org/lkml/Y+Ja5SRs886CEz7a@kadam/
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230527010644.647900-5-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-iocost.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/block/blk-iocost.c b/block/blk-iocost.c index 6084a9519883..9dfcf540f400 100644 --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -3301,11 +3301,9 @@ static ssize_t ioc_qos_write(struct kernfs_open_file *of, char *input, blk_stat_enable_accounting(disk->queue); blk_queue_flag_set(QUEUE_FLAG_RQ_ALLOC_TIME, disk->queue); ioc->enabled = true; - wbt_disable_default(disk); } else { blk_queue_flag_clear(QUEUE_FLAG_RQ_ALLOC_TIME, disk->queue); ioc->enabled = false; - wbt_enable_default(disk); } if (user) { @@ -3318,6 +3316,11 @@ static ssize_t ioc_qos_write(struct kernfs_open_file *of, char *input, ioc_refresh_params(ioc, true); spin_unlock_irq(&ioc->lock); + if (enable) + wbt_disable_default(disk); + else + wbt_enable_default(disk); + blk_mq_unquiesce_queue(disk->queue); blk_mq_unfreeze_queue(disk->queue); |