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Date:   Wed, 8 Jun 2022 14:01:50 +0200
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Subject: Re: [PATCH v2] sched/deadline: Use proc_douintvec_minmax() limit
 minimum value
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To:     Yajun Deng <yajun.deng@linux.dev>, mingo@redhat.com,
        peterz@infradead.org, juri.lelli@redhat.com,
        vincent.guittot@linaro.org, dietmar.eggemann@arm.com,
        rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de,
        vschneid@redhat.com
Cc:     linux-kernel@vger.kernel.org
References: <20220607101807.249965-1-yajun.deng@linux.dev>
From:   Daniel Bristot de Oliveira <bristot@redhat.com>
In-Reply-To: <20220607101807.249965-1-yajun.deng@linux.dev>
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On 6/7/22 12:18, Yajun Deng wrote:
> sysctl_sched_dl_period_max and sysctl_sched_dl_period_min are unsigned
> integer, but proc_dointvec() wouldn't return error even if we set a
> negative number.
> 
> Use proc_douintvec_minmax() instead of proc_dointvec(). Add extra1 for
> sysctl_sched_dl_period_max and extra2 for sysctl_sched_dl_period_min.
> 
> It's just an optimization for match data and proc_handler in struct
> ctl_table. The 'if (period < min || period > max)' in __checkparam_dl()
> will work fine even if there hasn't this patch.
> 
> v2:
>  - update the log message.
> 
> Signed-off-by: Yajun Deng <yajun.deng@linux.dev>

Reviewed-by: Daniel Bristot de Oliveira <bristot@kernel.org>
-- Daniel