linux-kernel - Re: [PATCH] mtd: spi-nor: replace unnecessary div64_u64() with div

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Message-ID: <mafs05xw0cn8v.fsf@kernel.org>
Date: Mon, 29 Apr 2024 15:27:44 +0200
From: Pratyush Yadav <pratyush@...nel.org>
To: Michael Walle <mwalle@...nel.org>
Cc: Tudor Ambarus <tudor.ambarus@...aro.org>,  Pratyush Yadav
 <pratyush@...nel.org>,  Miquel Raynal <miquel.raynal@...tlin.com>,
  Richard Weinberger <richard@....at>,  Vignesh Raghavendra
 <vigneshr@...com>,  Dan Carpenter <dan.carpenter@...aro.org>,
  linux-mtd@...ts.infradead.org,  linux-kernel@...r.kernel.org
Subject: Re: [PATCH] mtd: spi-nor: replace unnecessary div64_u64() with
 div_u64()

Hi,

On Mon, Apr 29 2024, Michael Walle wrote:

> Both occurences of div64_u64() just have a u8 or u32 divisor. Use
> div_u64() instead.

Does this improve performance or is this only for correctness?

Patch LGTM otherwise.

Reviewed-by: Pratyush Yadav <pratyush@...nel.org>

BTW, I also noticed that there is a do_div() call in spi_nor_write()
that also uses a u64 dividend and u32 divisor. I was wondering why it
uses do_div() and not div_u64() (I am not sure what the difference
between the two is) but I suppose it doesn't matter much since your
spring cleaning series will delete that code anyway.

-- 
Regards,
Pratyush Yadav