linux-kernel - Re: [PATCH] mtd: ubi: avoid expensive do

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Message-ID: <ecc5d070-a773-1180-b50c-59088b23695e@huawei.com>
Date: Wed, 13 Mar 2024 21:43:54 +0800
From: Zhihao Cheng <chengzhihao1@...wei.com>
To: Arnd Bergmann <arnd@...nel.org>, Arnd Bergmann <arnd@...db.de>, Richard
 Weinberger <richard@....at>, Miquel Raynal <miquel.raynal@...tlin.com>,
	Vignesh Raghavendra <vigneshr@...com>, Daniel Golle <daniel@...rotopia.org>
CC: <linux-mtd@...ts.infradead.org>, <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] mtd: ubi: avoid expensive do_div() on 32-bit machines

在 2024/3/13 21:39, Arnd Bergmann 写道:

>> Thanks for explaination, which means that do_div is used for 64-bit
>> division to solve the link failure caused by missed libgcc. Since
>> parameter 'from' is u32, there is no need to invoke do_div on a 32-bit
>> platform, you just want to stop the wasting behavior on a 32-bit
>> platform. Do I understand right?
> 
> Yes, correct.
> 
>        Arnd
> .
> 
How do you find it? I mean there are so many types and many do_div 
callers, do you have a static check tool?