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Date: Tue, 17 May 2016 10:27:12 +0900
From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Subject: Re: [PATCH v5 08/12] zsmalloc: introduce zspage structure
Message-ID: <20160517012712.GA497@swordfish>
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On (05/17/16 10:14), Minchan Kim wrote:
[..]
> > can we also switch create_cache() to errnos? I just like a bit
> > better
> > 		return -ENOMEM;
> > 	else
> > 		return 0;
> > 
> > than
> > 
> > 		return 1;
> > 	else
> > 		return 0;
> > 
> 
> Hmm, of course, I can do it easily.
> But zs_create_pool returns NULL without error propagation from sub
> functions so I don't see any gain from returning errno from
> create_cache. I don't mean I hate it but just need a justificaion
> to persuade grumpy me.

:) not married to those errnos. can skip it.

> > > +static struct zspage *isolate_zspage(struct size_class *class, bool source)
> > >  {
> > > +	struct zspage *zspage;
> > > +	enum fullness_group fg[2] = {ZS_ALMOST_EMPTY, ZS_ALMOST_FULL};
> > > +	if (!source) {
> > > +		fg[0] = ZS_ALMOST_FULL;
> > > +		fg[1] = ZS_ALMOST_EMPTY;
> > > +	}
> > > +
> > > +	for (i = 0; i < 2; i++) {
> > 
> > sorry, why not "for (i = ZS_ALMOST_EMPTY; i <= ZS_ALMOST_FULL ..." ?
> 
> For source zspage, the policy is to find a fragment object from ZS_ALMOST_EMPTY.
> For target zspage, the policy is to find a fragment object from ZS_ALMOST_FULL.
> 
> Do I misunderstand your question?

ahhh... sorry, it's just me being silly. I got it now.

	-ss