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Date:   Fri, 14 May 2021 13:47:15 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     kajoljain <kjain@linux.ibm.com>
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
Subject: Re: [RFC 1/4] drivers/nvdimm: Add perf interface to expose nvdimm
 performance stats
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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.