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From:   SeongJae Park <sj@kernel.org>
To:     Zeng Jingxiang <zengjx95@gmail.com>
Cc:     sj@kernel.org, akpm@linux-foundation.org, damon@lists.linux.dev,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Zeng Jingxiang <linuszeng@tencent.com>
Subject: Re: [PATCH] mm/damon: remove dead code in damon_lru_sort_enabled_store()
Date:   Fri, 12 Aug 2022 01:50:18 +0000
Message-Id: <20220812015018.115955-1-sj@kernel.org>
In-Reply-To: <20220812012459.481215-1-zengjx95@gmail.com>
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Hi Zeng,

On Fri, 12 Aug 2022 09:24:59 +0800 Zeng Jingxiang <zengjx95@gmail.com> wrote:

> From: Zeng Jingxiang <linuszeng@tencent.com>
> 
> The variable damon_lru_sort_initialized is always true, causing the
> corresponding conditional expression cannot be executed.
> 
> Assigning true to damon_lru_sort_initialized here
> 544         damon_lru_sort_initialized = true;

Before the assignment, the variable is set 'false'.

> 
> The value of damon_lru_sort_initialized is always true.
> As a result, the following expression cannot be executed.
> 
> 463         if (!damon_lru_sort_initialized)
> 464                 return rc;

If this code is executed before the assignment, the expression can be executed.

Actually, there was a bug due to the absence of the variable.  You may refer to
that for the detail:
https://lore.kernel.org/damon/20220604192222.1488-1-sj@kernel.org/T/#t


Thanks,
SJ

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