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From:   Zi Yan <ziy@nvidia.com>
To:     Randy Dunlap <rdunlap@infradead.org>
Cc:     linux-mm@kvack.org, David Hildenbrand <david@redhat.com>,
        Matthew Wilcox <willy@infradead.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        John Hubbard <jhubbard@nvidia.com>,
        Yang Shi <shy828301@gmail.com>,
        David Rientjes <rientjes@google.com>,
        James Houghton <jthoughton@google.com>,
        Mike Rapoport <rppt@kernel.org>, linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH v2 09/12] mm: Make MAX_ORDER of buddy allocator
 configurable via Kconfig SET_MAX_ORDER.
Date:   Fri, 12 Aug 2022 22:37:15 -0400
Message-ID: <25D8229F-CFB1-46FE-B4C8-7D2EBEAB10AC@nvidia.com>
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References: <20220811231643.1012912-1-zi.yan@sent.com>
 <20220811231643.1012912-10-zi.yan@sent.com>
 <becc0751-9ce9-6fab-8e58-477e962e54c5@infradead.org>
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On 12 Aug 2022, at 21:11, Randy Dunlap wrote:

> Hi--
>
> On 8/11/22 16:16, Zi Yan wrote:
>
>> diff --git a/mm/Kconfig b/mm/Kconfig
>> index bbe31e85afee..e558f5679707 100644
>> --- a/mm/Kconfig
>> +++ b/mm/Kconfig
>> @@ -441,6 +441,20 @@ config SPARSEMEM_VMEMMAP
>>  	  pfn_to_page and page_to_pfn operations.  This is the most
>>  	  efficient option when sufficient kernel resources are available.
>>
>> +config SET_MAX_ORDER
>> +	int "Set maximum order of buddy allocator"
>> +    depends on SPARSEMEM_VMEMMAP && (ARCH_FORCE_MAX_ORDER = 0)
>> +	range 10 255
>> +	default "10"
>> +	help
>> +	  The kernel memory allocator divides physically contiguous memory
>> +	  blocks into "zones", where each zone is a power of two number of
>> +	  pages.  This option selects the largest power of two that the kernel
>> +	  keeps in the memory allocator.  If you need to allocate very large
>> +	  blocks of physically contiguous memory, then you may need to
>> +	  increase this value. A value of 10 means that the largest free memory
>> +	  block is 2^10 pages.
>
> Please make sure that all lines of help text are indented with one tab + 2 spaces,
> as specified in Documentation/process/coding-style.rst.

I guess you mean the wrong indentation of "depends on" here, since all
the help text is correctly indented. Thanks. I fixed it locally.

--
Best Regards,
Yan, Zi

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