Date:   Wed, 1 Mar 2023 17:55:44 +0900
From:   Sergey Senozhatsky <senozhatsky@chromium.org>
To:     Minchan Kim <minchan@kernel.org>
Cc:     Sergey Senozhatsky <senozhatsky@chromium.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Yosry Ahmed <yosryahmed@google.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCHv2 3/6] zsmalloc: fine-grained inuse ratio based fullness
 grouping
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On (23/02/28 14:53), Minchan Kim wrote:
> BTW, I still prefer the enum instead of 10 define.
> 
> enum fullness_group {
>     ZS_EMPTY,
>     ZS_INUSE_RATIO_MIN,
>     ZS_INUSE_RATIO_ALMOST_FULL = 7,
>     ZS_INUSE_RATIO_MAX = 10,
>     ZS_FULL,
>     NR_ZS_FULLNESS,
> }

For educational purposes, may I ask what do enums give us? We
always use integers - int:4 in zspage fullness, int for arrays
offsets and we cast to plain integers in get/set stats. So those
enums exist only at declaration point, and plain int otherwise.
What are the benefits over #defines?