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Message-ID: <384a9be4-8123-3b3a-3be7-c549c8126fc8@arm.com>
Date:   Wed, 13 Dec 2023 18:05:06 +0000
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Subject: Re: [PATCH v7 09/24] x86/resctrl: Use __set_bit()/__clear_bit()
 instead of open coding
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To:     Reinette Chatre <reinette.chatre@intel.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org
Cc:     Fenghua Yu <fenghua.yu@intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        H Peter Anvin <hpa@zytor.com>,
        Babu Moger <Babu.Moger@amd.com>,
        shameerali.kolothum.thodi@huawei.com,
        D Scott Phillips OS <scott@os.amperecomputing.com>,
        carl@os.amperecomputing.com, lcherian@marvell.com,
        bobo.shaobowang@huawei.com, tan.shaopeng@fujitsu.com,
        baolin.wang@linux.alibaba.com, Jamie Iles <quic_jiles@quicinc.com>,
        Xin Hao <xhao@linux.alibaba.com>, peternewman@google.com,
        dfustini@baylibre.com, amitsinght@marvell.com
References: <20231025180345.28061-1-james.morse@arm.com>
 <20231025180345.28061-10-james.morse@arm.com>
 <7b6ae291-b1df-4a4a-a415-da1eaeed6775@intel.com>
From:   James Morse <james.morse@arm.com>
In-Reply-To: <7b6ae291-b1df-4a4a-a415-da1eaeed6775@intel.com>
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Precedence: bulk

Hi Reinette,

On 09/11/2023 17:44, Reinette Chatre wrote:
> On 10/25/2023 11:03 AM, James Morse wrote:
>> The resctrl CLOSID allocator uses a single 32bit word to track which
>> CLOSID are free. The setting and clearing of bits is open coded.
>>
>> A subsequent patch adds closid_allocated(), which adds more open
> 
> (Note use of "A subsequent patch ")

Yup, I've dropped this paragraph.


>> coded bitmaps operations. These will eventually need changing to use
>> the bitops helpers so that a CLOSID bitmap of the correct size can be
>> allocated dynamically.
>>
>> Convert the existing open coded bit manipulations of closid_free_map
>> to use __set_bit() and friends. These don't need to be atomic as this
>> list is protected by the mutex.

>> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> index 9864cb49d58c..f6051a3e7262 100644
>> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> @@ -131,7 +131,7 @@ static void closid_init(void)
>>  	closid_free_map = BIT_MASK(rdt_min_closid) - 1;
>>  
>>  	/* CLOSID 0 is always reserved for the default group */
> 
> Seems appropriate for the comment to be updated to the new define also.

Sure,

> With that addressed you can add:
> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>

Thanks!

James