Re: [PATCH stable] block/mq-deadline: fix different priority request on the same zone

From: Wu Bo
Date: Fri May 17 2024 - 20:53:18 EST


On 2024/5/18 01:53, Bart Van Assche wrote:
On 5/16/24 18:44, Wu Bo wrote:
So I figured this solution to fix this priority issue on zoned device. It sure
raises the overhead but can do fix it.

Something I should have realized earlier is that this patch is not
necessary with the latest upstream kernel (v6.10-rc1). Damien's zoned
write plugging patch series has been merged. Hence, I/O schedulers,
including the mq-deadline I/O schedulers, will only see a single
zoned write at a time per zone. So it is no longer possible that
zoned writes are reordered by the I/O scheduler because of their I/O
priorities.
Hi Bart,

Yes, I noticed that 'zone write plugging' has been merged to latest
branch. But it seems hard to backport to old version which mq-deadline
priority feature has been merged. So is it possible to apply this fix to
old versions?

Thanks,
Wu Bo

Thanks,

Bart.