Re: [PATCHv3 1/1] block: introduce content activity based ioprio

[Zhaoyang Huang]

On Thu, Jan 25, 2024 at 6:10 PM Zhaoyang Huang <huangzhaoyang@gmailcom> wrote:
>
> On Thu, Jan 25, 2024 at 5:54 PM Damien Le Moal <dlemoal@xxxxxxxxxx> wrote:
> >
> > On 1/25/24 18:37, Zhaoyang Huang wrote:
> > > Actually, the activity information comes from page's history (recorded
> > > at page cache's slot) instead of user space in step(1) and can be
> > > associate with bio in step(2) or iterate the bio in step(3)
> > > page fault(or vfs)(1)
> > > |
> > > alloc_pages
> > > |
> > > add_page_to_pagecache(get the page's activity information)
> > > |
> > > fs_readpage
> > > |
> > > bio_add_page(2)
> > > |
> >
> > set your prio here. No change to the block layer needed. That is FS land.
> Yes, that is what I suggested in patchv3 which keeps the block layer
> clean by introducing a set of helper functions which wrap up the
> activity things for FS utilization.
Maybe I misunderstand Damien's opinion which suggests iterating the
bio->bvec here via a new API. I think it is more costly than counting
activities when adding pages to bio and need more modifications on
each fs.
> >
> > > submit_bio(3)
> >
> >
> > --
> > Damien Le Moal
> > Western Digital Research
> >