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Subject: Re: [PATCH] mm/hugetlb.c: remove dead store in demote_size_show()
To:     Nghia Le <nghialm78@gmail.com>
Cc:     Matthew Wilcox <willy@infradead.org>, akpm@linux-foundation.org,
        nathan@kernel.org, ndesaulniers@google.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, llvm@lists.linux.dev,
        lukas.bulwahn@gmail.com, kernel-janitors@vger.kernel.org
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From:   Mike Kravetz <mike.kravetz@oracle.com>
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Date:   Mon, 4 Oct 2021 15:46:45 -0700
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On 10/3/21 8:44 PM, Nghia Le wrote:
> On Sun, Oct 03, 2021 at 07:36:54PM -0700, Mike Kravetz wrote:
>> On 10/3/21 6:54 AM, Matthew Wilcox wrote:
>>> On Sun, Oct 03, 2021 at 06:41:13PM +0700, Nghia Le wrote:
>>>>  {
>>>>  	struct hstate *h;
>>>> -	unsigned long demote_size;
>>>>  	int nid;
>>>>  
>>>>  	h = kobj_to_hstate(kobj, &nid);
>>>> -	demote_size = h->demote_order;
>>>>  
>>>>  	return sysfs_emit(buf, "%lukB\n",
>>>>  			(unsigned long)(PAGE_SIZE << h->demote_order) / SZ_1K);
>>>
>>> I'd suggest this function would look better written as:
>>>
>>> 	int nid;
>>> 	struct hstate *h = kobj_to_hstate(kobj, &nid);
>>> 	unsigned long demote_size = (PAGE_SIZE << h->demote_order) / SZ_1K;
>>>
>>> 	return sysfs_emit(buf, "%lukB\n", demote_size);
>>>
> Thanks Matthew for the clean code.
>>
>> Thank you Nghia Le for spotting this, and thank you Matthew for the
>> suggestion.
>>
>> This is still just in Andrew's tree and subject to modification before
>> the next merge window.  I am still expecting additional comments on the
>> series.
>>
>> If another version of the series is needed, I will include Matthew's
>> suggestion.   If not, I will ask Andrew how he would prefer to fold in
>> the changes.
>> -- 
>> Mike Kravetz
> Thanks Mike, so we will wait further comments from Andrew and others.

Yes, I received suggestions for other improvements to the patch which
contains this code.  I will be putting together another version of the
series with at least these changes.

Thanks,
-- 
Mike Kravetz