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Date:   Fri, 28 Jul 2023 17:35:33 +0100
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From:   James Morse <james.morse@arm.com>
Subject: Re: [PATCH v4 06/24] x86/resctrl: Track the number of dirty RMID a
 CLOSID has
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,
        xingxin.hx@openanolis.org, baolin.wang@linux.alibaba.com,
        Jamie Iles <quic_jiles@quicinc.com>,
        Xin Hao <xhao@linux.alibaba.com>, peternewman@google.com,
        dfustini@baylibre.com
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 <20230525180209.19497-7-james.morse@arm.com>
 <caa21966-967c-77c0-c2ca-8747677e186a@intel.com>
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Hi Reinette,

On 6/15/23 23:08, Reinette Chatre wrote:
> On 5/25/2023 11:01 AM, James Morse wrote:
>> @@ -420,6 +438,9 @@ static void add_rmid_to_limbo(struct rmid_entry *entry)
>>   		rmid_limbo_count++;
>>   	else
>>   		list_add_tail(&entry->list, &rmid_free_lru);
>> +
>> +	if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID))
>> +		closid_num_dirty_rmid[entry->closid]++;
   
> Wouldn't this always increment the counter, whether the entry is
> dirty or not? (Although ... the later change where entries are
> always dirty may make this correct ... although I would still
> expect the if statement that precedes it to change).

True, I was expecting add_rmid_to_limbo() to always transiently add CLOSID to limbo,
hence this is unconditional, but you're right its optional - and this could cause everything
to pile up in the list when the limbo handler isn't running.
I'll add a check on entry->busy, and move this into the above if case.


Thanks,

James