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References: <20240123093352.3007660-1-zhaoyang.huang@unisoc.com> <Za+5uEpmNWbT8tXt@infradead.org>
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From: Zhaoyang Huang <huangzhaoyang@gmail.com>
Date: Wed, 24 Jan 2024 15:53:50 +0800
Message-ID: <CAGWkznEu5u1-MgK1XoexDkRetp34b_D1KvmDLfaOayY959BBOw@mail.gmail.com>
Subject: Re: [PATCH] block: introduce content activity based ioprio
To: Christoph Hellwig <hch@infradead.org>
Cc: "zhaoyang.huang" <zhaoyang.huang@unisoc.com>, Jens Axboe <axboe@kernel.dk>, 
	linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, 
	steve.kang@unisoc.com
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On Tue, Jan 23, 2024 at 9:06=E2=80=AFPM Christoph Hellwig <hch@infradead.or=
g> wrote:
>
> On Tue, Jan 23, 2024 at 05:33:52PM +0800, zhaoyang.huang wrote:
> >  #define ALLOC_CACHE_MAX              256
> > @@ -1069,12 +1070,21 @@ EXPORT_SYMBOL_GPL(bio_add_zone_append_page);
> >  void __bio_add_page(struct bio *bio, struct page *page,
> >               unsigned int len, unsigned int off)
> >  {
> > +     int class, level, hint, activity;
> > +
> > +     class =3D IOPRIO_PRIO_CLASS(bio->bi_ioprio);
> > +     level =3D IOPRIO_PRIO_LEVEL(bio->bi_ioprio);
> > +     hint =3D IOPRIO_PRIO_HINT(bio->bi_ioprio);
> > +     activity =3D IOPRIO_PRIO_ACTIVITY(bio->bi_ioprio);
> > +
> >       WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
> >       WARN_ON_ONCE(bio_full(bio, len));
> >
> >       bvec_set_page(&bio->bi_io_vec[bio->bi_vcnt], page, len, off);
> >       bio->bi_iter.bi_size +=3D len;
> >       bio->bi_vcnt++;
> > +     activity +=3D (bio->bi_vcnt <=3D IOPRIO_NR_ACTIVITY && PageWorkin=
gset(page)) ? 1 : 0;
>
> The block layer must not look at page bits.  I've fixed all this crap
> with a lot of work and we're not going to re-add it for another qute
> hack.  The place to figure out any kind of I/O priority is the file
> system (preferably using generic helpers).
ok, will use helper function in next version
>