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Subject: Re: [PATCH 1/2] clocksource: arm_arch_timer: Simplify and fix count
 reader code logic
To:     Marc Zyngier <maz@kernel.org>
References: <20200817122415.6568-1-zhukeqian1@huawei.com>
 <20200817122415.6568-2-zhukeqian1@huawei.com>
 <267c5f9151c39fd2dcd0ce0b09d96545@kernel.org>
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        Andrew Jones <drjones@redhat.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
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        James Morse <james.morse@arm.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
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From:   zhukeqian <zhukeqian1@huawei.com>
Message-ID: <2093b7c1-6ef4-c0ff-e9df-1f493fccdda8@huawei.com>
Date:   Tue, 18 Aug 2020 09:40:56 +0800
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Hi Marc,

On 2020/8/17 20:52, Marc Zyngier wrote:
> On 2020-08-17 13:24, Keqian Zhu wrote:
>> In commit 0ea415390cd3 (clocksource/arm_arch_timer: Use arch_timer_read_counter
>> to access stable counters), we separate stable and normal count reader. Actually
>> the stable reader can correctly lead us to normal reader if we has no
>> workaround.
> 
> Resulting in an unnecessary overhead on non-broken systems that can run
> without CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND. Not happening.
OK, so I got the purpose of that patch wrong.
> 
>> Besides, in erratum_set_next_event_tval_generic(), we use normal reader, it is
>> obviously wrong, so just revert this commit to solve this problem by the way.
> 
> If you want to fix something, post a patch that does exactly that.
> 
I will.

Thanks,
Keqian
>         M.