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Reply-To: "Hillf Danton" <hillf.zj@alibaba-inc.com>
From: "Hillf Danton" <hillf.zj@alibaba-inc.com>
To: "'Michal Hocko'" <mhocko@kernel.org>
Cc: <linux-mm@kvack.org>, "'Andrew Morton'" <akpm@linux-foundation.org>,
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References: <20170330115454.32154-1-mhocko@kernel.org> <20170330115454.32154-4-mhocko@kernel.org> <04ad01d2a9d1$d99b0540$8cd10fc0$@alibaba-inc.com> <20170331064901.GC27098@dhcp22.suse.cz>
In-Reply-To: <20170331064901.GC27098@dhcp22.suse.cz>
Subject: Re: [PATCH 3/6] mm: remove return value from init_currently_empty_zone
Date: Fri, 31 Mar 2017 15:06:41 +0800
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On March 31, 2017 2:49 PM Michal Hocko wrote: 
> On Fri 31-03-17 11:49:49, Hillf Danton wrote:
> [...]
> > > -/* Can fail with -ENOMEM from allocating a wait table with vmalloc() or
> > > - * alloc_bootmem_node_nopanic()/memblock_virt_alloc_node_nopanic() */
> > > -static int __ref ensure_zone_is_initialized(struct zone *zone,
> > > +static void __ref ensure_zone_is_initialized(struct zone *zone,
> > >  			unsigned long start_pfn, unsigned long num_pages)
> > >  {
> > > -	if (zone_is_empty(zone))
> > > -		return init_currently_empty_zone(zone, start_pfn, num_pages);
> > > -
> > > -	return 0;
> > > +	if (!zone_is_empty(zone))
> > > +		init_currently_empty_zone(zone, start_pfn, num_pages);
> > >  }
> > Semantic change added?
> 
> could you be more specific?

Well, I'm wondering why you are trying to initiate a nonempty zone.

Hillf