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Message-ID: <c3b60fb9-8a63-b1f6-059e-aeeabf6ba913@linux.alibaba.com>
Date:   Mon, 10 Jul 2023 18:41:17 +0800
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Subject: Re: [PATCH] erofs: avoid unnecessary loops in
 z_erofs_pcluster_readmore() when read page beyond EOF
To:     Chunhai Guo <guochunhai@vivo.com>, xiang@kernel.org,
        chao@kernel.org
Cc:     huyue2@coolpad.com, jefflexu@linux.alibaba.com,
        linux-erofs@lists.ozlabs.org, linux-kernel@vger.kernel.org
References: <20230710042531.28761-1-guochunhai@vivo.com>
From:   Gao Xiang <hsiangkao@linux.alibaba.com>
In-Reply-To: <20230710042531.28761-1-guochunhai@vivo.com>
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On 2023/7/10 12:25, Chunhai Guo wrote:
> z_erofs_pcluster_readmore() may take a long time to loop when the page
> offset is large enough, which is unnecessary should be prevented.
> For example, when the following case is encountered, it will loop 4691368
> times, taking about 27 seconds.
>      - offset = 19217289215
>      - inode_size = 1442672
> 
> Signed-off-by: Chunhai Guo <guochunhai@vivo.com>

I will update the subject manually to:
"erofs: avoid useless loops in z_erofs_pcluster_readmore() when reading beyond EOF"

to avoid overly long subject as well...

Thanks,
Gao Xiang