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Date:   Fri, 5 Feb 2021 12:12:17 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Minchan Kim <minchan@kernel.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: <20210205121217.GH308988@casper.infradead.org>
References: <20210203155001.4121868-1-minchan@kernel.org>
 <20210205025526.GG308988@casper.infradead.org>
 <YBzWCl0MVNWntyUZ@google.com>
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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);