Re: [PATCH] blk-cgroup: fix missing pd_online_fn() while activating policy
From: Yu Kuai
Date: Thu Jan 05 2023 - 08:56:31 EST
Hi,
在 2023/01/05 18:45, Michal Koutný 写道:
On Thu, Jan 05, 2023 at 09:43:02AM +0800, Yu Kuai <yukuai1@xxxxxxxxxxxxxxx> wrote:
This is based only on code review, currently the only negative effects
is that root blkg from blk-throtl won't call pd_online_fn().
Good, that's a NOP and there are no other uses of pd_online_fn.
I wonder are the separate pd_init_fn and pd_online_fn callbacks
necessary today?
I think online can combine to init, consider that only blk-throttle
implement pd_online_fn(), but I'm not sure...
It seems to me the policies(bfq, iocost...) seem don't honor how pd
apis works: alloc->init->online->offline->free, bfq combines online to
init, iocost combines offline to free, ...
Thanks,
Kuai