Commit 074501bc authored by Yu Kuai's avatar Yu Kuai Committed by Jens Axboe
Browse files

blk-iocost: read 'ioc->params' inside 'ioc->lock' in ioc_timer_fn() 



'ioc->params' is updated in ioc_refresh_params(), which is proteced by
'ioc->lock', however, ioc_timer_fn() read params outside the lock.

Signed-off-by: default avatarYu Kuai <yukuai3@huawei.com>
Acked-by: default avatarTejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221012094035.390056-5-yukuai1@huaweicloud.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 2b2da2f6

block/blk-iocost.c

+4 −2
Original line number Diff line number Diff line
@@ -2203,8 +2203,8 @@ static void ioc_timer_fn(struct timer_list *timer) 
	LIST_HEAD(surpluses);

	int nr_debtors, nr_shortages = 0, nr_lagging = 0;

	u64 usage_us_sum = 0;

	u32 ppm_rthr = MILLION - ioc->params.qos[QOS_RPPM];

	u32 ppm_wthr = MILLION - ioc->params.qos[QOS_WPPM];

	u32 ppm_rthr;

	u32 ppm_wthr;

	u32 missed_ppm[2], rq_wait_pct;

	u64 period_vtime;

	int prev_busy_level;
@@ -2215,6 +2215,8 @@ static void ioc_timer_fn(struct timer_list *timer) 
	/* take care of active iocgs */

	spin_lock_irq(&ioc->lock);



	ppm_rthr = MILLION - ioc->params.qos[QOS_RPPM];

	ppm_wthr = MILLION - ioc->params.qos[QOS_WPPM];

	ioc_now(ioc, &now);



	period_vtime = now.vnow - ioc->period_at_vtime;