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Subject: Re: [PATCH v5 12/16] PCI: Add pci_iomap_host_shared(),
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To:     "Reshetova, Elena" <elena.reshetova@intel.com>,
        "Williams, Dan J" <dan.j.williams@intel.com>,
        "Michael S. Tsirkin" <mst@redhat.com>
Cc:     Kuppuswamy Sathyanarayanan 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Peter Zijlstra <peterz@infradead.org>,
        "Lutomirski, Andy" <luto@kernel.org>,
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From:   Andi Kleen <ak@linux.intel.com>
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On 10/12/2021 11:36 AM, Reshetova, Elena wrote:
>> The 5.15 tree has something like ~2.4k IO accesses (including MMIO and
>> others) in init functions that also register drivers (thanks Elena for
>> the number)
> To provide more numbers on this. What I can see so far from a smatch-based
> analysis, we have 409 __init style functions (.probe & builtin/module_
> _platform_driver_probe excluded) for 5.15 with allyesconfig. The number of
> distinct individual IO reads (MSRs included) is much higher than 2.4k and on the
> range of 30k because quite often there are more than a single IO read in the
> same source function. The full list of accesses and the possible call paths is huge
> for manually looking at, but here is the list of the 409 functions if anyone wants
> to take a look:


Thanks Elena.


I suspect the true number is even higher because that doesn't include IO 
inside calls to other modules and indirect pointers, correct?


-Andi