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Subject: Re: [PATCH 2/6] arm64/mm: Enable memory hot remove
To:     Oscar Salvador <osalvador@suse.de>
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From:   Anshuman Khandual <anshuman.khandual@arm.com>
Message-ID: <0c2b5096-a6df-b4ac-ac3b-3fec274837d3@arm.com>
Date:   Thu, 4 Apr 2019 18:33:09 +0530
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On 04/04/2019 05:28 PM, Oscar Salvador wrote:
> On Thu, Apr 04, 2019 at 11:09:22AM +0530, Anshuman Khandual wrote:
>>> Do these need to be __meminit? AFAICS it's effectively redundant with the containing #ifdef, and removal feels like it's inherently a later-than-init thing anyway.
>>
>> I was confused here a bit but even X86 does exactly the same. All these functions
>> are still labeled __meminit and all wrapped under CONFIG_MEMORY_HOTPLUG. Is there
>> any concern to have __meminit here ?
> 
> We do not really need it as long as the code is within #ifdef CONFIG_MEMORY_HOTPLUG.
> __meminit is being used when functions that are going to be need for hotplug need
> to stay around.

Makes sense.

> 
> /* Used for MEMORY_HOTPLUG */
> #define __meminit        __section(.meminit.text) __cold notrace \
>                                                   __latent_entropy
> 
> #if defined(CONFIG_MEMORY_HOTPLUG)
> #define MEM_KEEP(sec)    *(.mem##sec)
> #define MEM_DISCARD(sec)
> #else
> #define MEM_KEEP(sec)
> #define MEM_DISCARD(sec) *(.mem##sec)
> #endif
> 
> So it is kind of redundant to have both.
> I will clean it up when reposting [1] and [2].
> 
> [1] https://patchwork.kernel.org/patch/10875019/
> [2] https://patchwork.kernel.org/patch/10875021/
> 

Sure. Will remove them from the proposed functions next time around.