netdev - Re: [PATCH v3 01/16] bitops: Change parity8() return type to bool

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Message-ID: <20250306204544.35086b52@pumpkin>
Date: Thu, 6 Mar 2025 20:45:44 +0000
From: David Laight <david.laight.linux@...il.com>
To: Kuan-Wei Chiu <visitorckw@...il.com>
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 Yu-Chun Lin <eleanor15x@...il.com>
Subject: Re: [PATCH v3 01/16] bitops: Change parity8() return type to bool

On Fri,  7 Mar 2025 00:25:26 +0800
Kuan-Wei Chiu <visitorckw@...il.com> wrote:

> Change return type to bool for better clarity. Update the kernel doc
> comment accordingly, including fixing "@value" to "@val" and adjusting
> examples. Also mark the function with __attribute_const__ to allow
> potential compiler optimizations.

If the result type is 'bool' you should just check it.
Not compare against true/false.

	David

> 
> Co-developed-by: Yu-Chun Lin <eleanor15x@...il.com>
> Signed-off-by: Yu-Chun Lin <eleanor15x@...il.com>
> Signed-off-by: Kuan-Wei Chiu <visitorckw@...il.com>
> ---
>  include/linux/bitops.h | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/include/linux/bitops.h b/include/linux/bitops.h
> index c1cb53cf2f0f..44e5765b8bec 100644
> --- a/include/linux/bitops.h
> +++ b/include/linux/bitops.h
> @@ -231,26 +231,26 @@ static inline int get_count_order_long(unsigned long l)
>  
>  /**
>   * parity8 - get the parity of an u8 value
> - * @value: the value to be examined
> + * @val: the value to be examined
>   *
>   * Determine the parity of the u8 argument.
>   *
>   * Returns:
> - * 0 for even parity, 1 for odd parity
> + * false for even parity, true for odd parity
>   *
>   * Note: This function informs you about the current parity. Example to bail
>   * out when parity is odd:
>   *
> - *	if (parity8(val) == 1)
> + *	if (parity8(val) == true)
>   *		return -EBADMSG;
>   *
>   * If you need to calculate a parity bit, you need to draw the conclusion from
>   * this result yourself. Example to enforce odd parity, parity bit is bit 7:
>   *
> - *	if (parity8(val) == 0)
> + *	if (parity8(val) == false)
>   *		val ^= BIT(7);
>   */
> -static inline int parity8(u8 val)
> +static inline __attribute_const__ bool parity8(u8 val)
>  {
>  	/*
>  	 * One explanation of this algorithm: