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From:   Thomas Gleixner <tglx@linutronix.de>
To:     Yury Norov <yury.norov@gmail.com>, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH 11/16] time: optimize tick_check_preferred()
In-Reply-To: <87fsi9rcxu.ffs@tglx>
References: <20220718192844.1805158-1-yury.norov@gmail.com>
 <20220718192844.1805158-12-yury.norov@gmail.com> <87fsi9rcxu.ffs@tglx>
Date:   Mon, 08 Aug 2022 13:42:54 +0200
Message-ID: <87czdbq7up.ffs@tglx>
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On Sat, Aug 06 2022 at 10:30, Thomas Gleixner wrote:
> On Mon, Jul 18 2022 at 12:28, Yury Norov wrote:
>
>> tick_check_preferred() calls cpumask_equal() even if
>> curdev->cpumask == newdev->cpumask. Fix it.
>
> What's to fix here? It's a pointless operation in a slow path and all
> your "fix' is doing is to make the code larger.

In fact cpumask_equal() should have the ptr1 == ptr2 check, so you don't
have to add it all over the place.

Thanks,

        tglx