On Thu, Jan 25, 2024 at 6:10 PM Zhaoyang Huang <huangzhaoyang@xxxxxxxxx> 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 > >