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Subject: Re: [RFC 1/4] drivers/nvdimm: Add perf interface to expose nvdimm
 performance stats
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org,
        linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org,
        maddy@linux.vnet.ibm.com, santosh@fossix.org,
        aneesh.kumar@linux.ibm.com, vaibhav@linux.ibm.com,
        dan.j.williams@intel.com, ira.weiny@intel.com,
        atrajeev@linux.vnet.ibm.com, tglx@linutronix.de
References: <20210512163824.255370-1-kjain@linux.ibm.com>
 <20210512163824.255370-2-kjain@linux.ibm.com>
 <YJwP9ByvAcDPixVN@hirez.programming.kicks-ass.net>
 <37015d53-050a-acef-2958-b1ff5d02800b@linux.ibm.com>
 <YJ5jQ1ixz7D0Ij2R@hirez.programming.kicks-ass.net>
From:   kajoljain <kjain@linux.ibm.com>
Message-ID: <f15d6de4-8152-4960-8716-16bd9a12357b@linux.ibm.com>
Date:   Mon, 17 May 2021 12:13:00 +0530
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On 5/14/21 5:17 PM, Peter Zijlstra wrote:
> On Thu, May 13, 2021 at 05:56:14PM +0530, kajoljain wrote:
> 
>> But yes the current read/add/del functions are not adding value. We
>> could  add an arch/platform specific function which could handle the
>> capturing of the counter data and do the rest of the operation here,
>> is this approach better?
> 
> Right; have your register_nvdimm_pmu() set pmu->{add,del,read} to
> nd_pmu->{add,del,read} directly, don't bother with these intermediates.
> Also you can WARN_ON_ONCE() if any of them are NULL and fail
> registration at that point.
> 

Hi Peter,
    I will make all required changes and send next version of this patchset soon.

Thanks,
Kajol Jain