linux-kernel - Re: [PATCH] cpufreq: Replace double NOT (!!) with single NOT (!)

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Date:   Tue, 19 Feb 2019 11:20:12 +0100
From:   "Rafael J. Wysocki" <rjw@...ysocki.net>
To:     Viresh Kumar <viresh.kumar@...aro.org>
Cc:     linux-pm@...r.kernel.org,
        Vincent Guittot <vincent.guittot@...aro.org>,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] cpufreq: Replace double NOT (!!) with single NOT (!)

On Thursday, February 14, 2019 11:46:21 AM CET Viresh Kumar wrote:
> Double NOT (!!) operation is normally done to convert a non-zero value
> to 1 and keep zero as is, but that isn't the requirement in this case.
> All we wanted was to make sure that only one of the two routines isn't
> set, i.e. either both function pointers are set or both are unset.
> 
> This can be done with a single NOT (!) operation as well.
> 
> Signed-off-by: Viresh Kumar <viresh.kumar@...aro.org>
> ---
>  drivers/cpufreq/cpufreq.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index 55e9795801a4..ad4e9991c3cc 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -2505,7 +2505,7 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
>  		    driver_data->target) ||
>  	     (driver_data->setpolicy && (driver_data->target_index ||
>  		    driver_data->target)) ||
> -	     (!!driver_data->get_intermediate != !!driver_data->target_intermediate) ||
> +	     (!driver_data->get_intermediate != !driver_data->target_intermediate) ||
>  	     (!driver_data->online != !driver_data->offline))
>  		return -EINVAL;
>  
> 

Applied, thanks!