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Date:   Fri, 16 Sep 2022 13:12:49 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Xin Hao <xhao@linux.alibaba.com>
Cc:     mike.kravetz@oracle.com, songmuchun@bytedance.com,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH V2] mm/hugetlb: add is_resv_equal_free() func
Message-Id: <20220916131249.68d59133cdb0366e0831592b@linux-foundation.org>
In-Reply-To: <20220916064127.1904-1-xhao@linux.alibaba.com>
References: <20220916064127.1904-1-xhao@linux.alibaba.com>
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On Fri, 16 Sep 2022 14:41:27 +0800 Xin Hao <xhao@linux.alibaba.com> wrote:

> In hugetlb.c file, there are several places to compare the values of
> 'h->free_huge_pages' and 'h->resv_huge_pages', it looks a bit messy, so
> there add a new is_resv_equal_free() func to do these.
> 
> ...
>
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -1191,6 +1191,11 @@ static struct page *dequeue_huge_page_nodemask(struct hstate *h, gfp_t gfp_mask,
>  	return NULL;
>  }
> 
> +static inline bool is_resv_equal_free(struct hstate *h)

I'm not sure that's a well chosen name.  A better name would reflect
the *meaning* of free_huge_pages being equal to resv_huge_pages.  Maybe
something like reserves_exhausted()?

This would all be clearer if we'd bothered to document the fields of
struct hstate :(


> +{
> +	return (h->free_huge_pages - h->resv_huge_pages == 0) ? true : false;

	return h->free_huge_pages == h->resv_huge_pages;

> +}