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Date: Fri, 5 Jan 2024 15:46:55 -0800
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Subject: Re: [PATCH] mm,page_alloc,cma: configurable CMA utilization
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To: Minchan Kim <minchan@kernel.org>,
        Chris Goldsworthy
	<quic_cgoldswo@quicinc.com>
CC: Roman Gushchin <roman.gushchin@linux.dev>,
        Andrew Morton
	<akpm@linux-foundation.org>,
        Rik van Riel <riel@surriel.com>, Roman Gushchin
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        Vlastimil Babka <vbabka@suse.cz>, Joonsoo Kim
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        Georgi Djakov <quic_c_gdjako@quicinc.com>, <linux-mm@kvack.org>,
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From: Sukadev Bhattiprolu <quic_sukadev@quicinc.com>
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On 2/1/2023 3:47 PM, Minchan Kim wrote:
>
> I like this patch for different reason but for the specific problem you
> mentioned, How about making reclaimer/compaction aware of the problem:
>
> IOW, when the GFP_KERNEL/DMA allocation happens but not enough memory
> in the zones, let's migrates movable pages in those zones into CMA
> area/movable zone if they are plenty of free memory.

Hi Minchan,

Coming back to this thread after a while.

If the CMA region is usually free, allocating pages first in the non-CMA
region and then moving them into the CMA region would be extra work since
it would happen most of the time. In such cases, wouldn't it be better to
allocate from the CMA region itself?

Sukadev