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Date: Thu, 29 Feb 2024 10:22:31 +0800
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Subject: Re: [PATCH v2] perf/hx_arm_ni: Support uncore ARM NI-700 PMU
To: Robin Murphy <robin.murphy@arm.com>, Will Deacon <will@kernel.org>,
 Mark Rutland <mark.rutland@arm.com>
Cc: shenghui.qu@shingroup.cn, linux-kernel@vger.kernel.org,
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在 2024/2/3 4:11, Robin Murphy 写道:
> On 2024-02-01 2:40 am, Yang Jialong 杨佳龙 wrote:
>>
>>
>> 在 2024/2/1 0:50, Robin Murphy 写道:
>>> On 31/01/2024 7:08 am, JiaLong.Yang wrote:
>>>> This code is based on uncore PMUs arm_smmuv3_pmu and arm-cmn.
>>>> One ni-700 can have many clock domains. Each of them has only one PMU.
>>>> Here one PMU corresponds to one 'struct ni_pmu' instance.
>>>> PMU name will be ni_pmu_N_M, which N means different NI-700s and M 
>>>> means
>>>> different PMU in one NI-700. If only one NI-700 found in NI-700, 
>>>> name will
>>>> be ni_pmu_N.
>>>> Node interface event name will be xxni_N_eventname, such as
>>>> asni_0_rdreq_any. There are many kinds of type of nodes in one clock
>>>> domain. Also means that there are many kinds of that in one PMU. So we
>>>> distinguish them by xxni string. Besides, maybe there are many nodes
>>>> have same type. So we have number N in event name.
>>>> By ni_pmu_0_0/asni_0_rdreq_any/, we can pinpoint accurate bus traffic.
>>>> Example1: perf stat -a -e 
>>>> ni_pmu_0_0/asni_0_rdreq_any/,ni_pmu_0_0/cycles/
>>>> EXample2: perf stat -a -e ni_pmu_0_0/asni,id=0,event=0x0/
>>>
>>> Oh! I've had a driver for this thing sat around for ages waiting to 
>>> find someone with an interest in testing it. Given that from a quick 
>>> skim of this patch I'd also have several concerns with this 
>>> implementation, may I ask that you have a look at my branch and see 
>>> if it works for you?
>>
>> If permission I will test.
> 
> Thanks! I see you've also tried to support having the IRQs combined 
> together - does your platform need that right away? That's another thing 
> I've been anticipating but haven't got round to wiring up yet (it's a 
> bit more fiddly than just IRQF_SHARED since perf has some expectations 
> around affinity to event->cpu), but I can have a go at getting it done.
> 

I have not seen the expectations. I will study it.

>>>
>>> https://gitlab.arm.com/linux-arm/linux-rm/-/tree/ni-dev?ref_type=heads
>>>
>>> In particular, after the pain of maintaining event aliases in arm-cmn 
>>> I'd really like to get away from doing that again and instead move 
>>> over to jevents this time (especially now that system PMU support is 
>>> a bit more developed there) - I just haven't yet got round to hooking 
>>> up the identifier and writing the JSON files, since it hasn't seemed 
>>> like much of a priority before I know whether the code even works.
>>>
>>
>> It's a useful way.
>> Uncore PMU is increasing. Not only CPU event can be writen in jevents.
>> I have not considered it when writing code in a low version.
>>
>> Finally, I have opened a case in arm suppport for linux ni pmu driver.
>> They tell me no driver.
> 
> Oh dear, sorry about that - I'd have hoped that a question about a Linux 
> PMU driver might have found its way to our team, even if they weren't 
> aware that NI-700 has already been a specific item on our roadmap for 
> some time :(
> 
> Thanks,
> Robin.
> 

I have run the code and thanks to the support of shenghui.qu@shingroup.cn.
It's sorry for the late.