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From:   Tianxianting <tian.xianting@h3c.com>
To:     Michal Hocko <mhocko@suse.com>
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Subject: RE: [PATCH] mm: Make allocator take care of memoryless numa node
Thread-Topic: [PATCH] mm: Make allocator take care of memoryless numa node
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Date:   Mon, 19 Oct 2020 07:14:31 +0000
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Thanks Michal,
Yes, it is the commit bffed457160ab. Sorry I forgot to paste it in my previous reply.


-----Original Message-----
From: Michal Hocko [mailto:mhocko@suse.com] 
Sent: Monday, October 19, 2020 3:07 PM
To: tianxianting (RD) <tian.xianting@h3c.com>
Cc: cl@linux.com; penberg@kernel.org; rientjes@google.com; iamjoonsoo.kim@lge.com; akpm@linux-foundation.org; linux-mm@kvack.org; linux-kernel@vger.kernel.org; kuba@kernel.org; alexei.starovoitov@gmail.com
Subject: Re: [PATCH] mm: Make allocator take care of memoryless numa node

On Sun 18-10-20 14:18:37, Tianxianting wrote:
> Thanks for the comments
> I found in current code, there are two places to call
> local_memory_node(node) before calling kzalloc_node(), I think we can 
> remove them?

I am not sure which code you are talking about. git grep shows me 2 places in blk-mq code (e.g. bffed457160ab) and that looks quite bogus to me. Bring that up with the respective maintainer and Raghavendra.
The changelog doesn't really describe any problem, if there is any. But from the allocator semantic point of view memory less nodes are to be expected and the allocator should fallback to the proper node. As long as __GFP_THISNODE is not enforced of course.
--
Michal Hocko
SUSE Labs