Commit 35198e32 authored by Yu Kuai's avatar Yu Kuai Committed by Jens Axboe
Browse files

blk-iocost: read params inside lock in sysfs apis 



Otherwise, user might get abnormal values if params is updated
concurrently.

Signed-off-by: default avatarYu Kuai <yukuai3@huawei.com>
Acked-by: default avatarTejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230117070806.3857142-4-yukuai1@huaweicloud.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 235a5a83

block/blk-iocost.c

+4 −0
Original line number Diff line number Diff line
@@ -3131,6 +3131,7 @@ static u64 ioc_qos_prfill(struct seq_file *sf, struct blkg_policy_data *pd, 
	if (!dname)

		return 0;



	spin_lock_irq(&ioc->lock);

	seq_printf(sf, "%s enable=%d ctrl=%s rpct=%u.%02u rlat=%u wpct=%u.%02u wlat=%u min=%u.%02u max=%u.%02u\n",

		   dname, ioc->enabled, ioc->user_qos_params ? "user" : "auto",

		   ioc->params.qos[QOS_RPPM] / 10000,
@@ -3143,6 +3144,7 @@ static u64 ioc_qos_prfill(struct seq_file *sf, struct blkg_policy_data *pd, 
		   ioc->params.qos[QOS_MIN] % 10000 / 100,

		   ioc->params.qos[QOS_MAX] / 10000,

		   ioc->params.qos[QOS_MAX] % 10000 / 100);

	spin_unlock_irq(&ioc->lock);

	return 0;

}
@@ -3322,12 +3324,14 @@ static u64 ioc_cost_model_prfill(struct seq_file *sf, 
	if (!dname)

		return 0;



	spin_lock_irq(&ioc->lock);

	seq_printf(sf, "%s ctrl=%s model=linear "

		   "rbps=%llu rseqiops=%llu rrandiops=%llu "

		   "wbps=%llu wseqiops=%llu wrandiops=%llu\n",

		   dname, ioc->user_cost_model ? "user" : "auto",

		   u[I_LCOEF_RBPS], u[I_LCOEF_RSEQIOPS], u[I_LCOEF_RRANDIOPS],

		   u[I_LCOEF_WBPS], u[I_LCOEF_WSEQIOPS], u[I_LCOEF_WRANDIOPS]);

	spin_unlock_irq(&ioc->lock);

	return 0;

}