[-next,2/2] blk-iocost: change div64_u64 to DIV64_U64_ROUND_UP in ioc_refresh_params()

Message ID 20221124140635.695205-2-linan122@huawei.com
State New
Headers
Series [-next,1/2] blk-iocost: fix divide by 0 error in calc_lcoefs() |

Commit Message

Li Nan Nov. 24, 2022, 2:06 p.m. UTC
  vrate_min is calculated by DIV64_U64_ROUND_UP, but vrate_max is calculated
by div64_u64. Vrate_min may be 1 greater than vrate_max if the input
values min and max of cost.qos are equal.

Signed-off-by: Li Nan <linan122@huawei.com>
---
 block/blk-iocost.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
  

Comments

Andreas Herrmann Nov. 25, 2022, 10:14 a.m. UTC | #1
On Thu, Nov 24, 2022 at 10:06:35PM +0800, Li Nan wrote:
> vrate_min is calculated by DIV64_U64_ROUND_UP, but vrate_max is calculated
> by div64_u64. Vrate_min may be 1 greater than vrate_max if the input
> values min and max of cost.qos are equal.
> 
> Signed-off-by: Li Nan <linan122@huawei.com>
> ---
>  block/blk-iocost.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Andreas Herrmann <aherrmann@suse.de>

> diff --git a/block/blk-iocost.c b/block/blk-iocost.c
> index a38a5324bf10..9030ad8672f3 100644
> --- a/block/blk-iocost.c
> +++ b/block/blk-iocost.c
> @@ -926,7 +926,7 @@ static bool ioc_refresh_params(struct ioc *ioc, bool force)
>  
>  	ioc->vrate_min = DIV64_U64_ROUND_UP((u64)ioc->params.qos[QOS_MIN] *
>  					    VTIME_PER_USEC, MILLION);
> -	ioc->vrate_max = div64_u64((u64)ioc->params.qos[QOS_MAX] *
> +	ioc->vrate_max = DIV64_U64_ROUND_UP((u64)ioc->params.qos[QOS_MAX] *
>  				   VTIME_PER_USEC, MILLION);
>  
>  	return true;
> -- 
> 2.31.1
>
  

Patch

diff --git a/block/blk-iocost.c b/block/blk-iocost.c
index a38a5324bf10..9030ad8672f3 100644
--- a/block/blk-iocost.c
+++ b/block/blk-iocost.c
@@ -926,7 +926,7 @@  static bool ioc_refresh_params(struct ioc *ioc, bool force)
 
 	ioc->vrate_min = DIV64_U64_ROUND_UP((u64)ioc->params.qos[QOS_MIN] *
 					    VTIME_PER_USEC, MILLION);
-	ioc->vrate_max = div64_u64((u64)ioc->params.qos[QOS_MAX] *
+	ioc->vrate_max = DIV64_U64_ROUND_UP((u64)ioc->params.qos[QOS_MAX] *
 				   VTIME_PER_USEC, MILLION);
 
 	return true;