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Sender: Minchan Kim <minchan.kim@gmail.com>
Date:   Fri, 5 Feb 2021 08:16:44 -0800
From:   Minchan Kim <minchan@kernel.org>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        gregkh@linuxfoundation.org, surenb@google.com, joaodias@google.com,
        LKML <linux-kernel@vger.kernel.org>,
        linux-mm <linux-mm@kvack.org>
Subject: Re: [PATCH] mm: cma: support sysfs
Message-ID: <YB1vbGJFJM3eLzOo@google.com>
References: <20210203155001.4121868-1-minchan@kernel.org>
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 <YBzWCl0MVNWntyUZ@google.com>
 <20210205121217.GH308988@casper.infradead.org>
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On Fri, Feb 05, 2021 at 12:12:17PM +0000, Matthew Wilcox wrote:
> On Thu, Feb 04, 2021 at 09:22:18PM -0800, Minchan Kim wrote:
> > > > +	for (i = 0; i < cma_area_count; i++) {
> > > > +		cma = &cma_areas[i];
> > > > +		stat = kzalloc(sizeof(*stat), GFP_KERNEL);
> > > > +		if (!stat)
> > > > +			goto out;
> > > 
> > > How many cma areas are there going to be?  do we really want to allocate
> > > their stat individually?
> > 
> > I am not sure what could be in the end but at least, I have
> > 5+ candidates (but could be shrink or extend) and yes,
> > want to keep track them individually.
> 
> I meant, wouldn't it be better to:
> 
> 	cma_stats = kzalloc(array_size(sizeof(*stat), cma_area_count),
> 				GFP_KERNEL);
> 

Definitely.
Thanks, Matthew.