Merge branch 'for-next/perf' into for-next/core

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Arm Network-on Chip Interconnect PMU

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NI-700 and friends implement a distinct PMU for each clock domain within the

interconnect. Correspondingly, the driver exposes multiple PMU devices named

arm_ni_<x>_cd_<y>, where <x> is an (arbitrary) instance identifier and <y> is

the clock domain ID within that particular instance. If multiple NI instances

exist within a system, the PMU devices can be correlated with the underlying

hardware instance via sysfs parentage.

Each PMU exposes base event aliases for the interface types present in its clock

domain. These require qualifying with the "eventid" and "nodeid" parameters

to specify the event code to count and the interface at which to count it

(per the configured hardware ID as reflected in the xxNI_NODE_INFO register).

The exception is the "cycles" alias for the PMU cycle counter, which is encoded

with the PMU node type and needs no further qualification.

DesignWare Cores (DWC) PCIe PMU Driver

=======================================

This driver adds PMU devices for each PCIe Root Port named based on the BDF of

This driver adds PMU devices for each PCIe Root Port named based on the SBDF of

the Root Port. For example,

    30:03.0 PCI bridge: Device 1ded:8000 (rev 01)

    0001:30:03.0 PCI bridge: Device 1ded:8000 (rev 01)

the PMU device name for this Root Port is dwc_rootport_3018.

the PMU device name for this Root Port is dwc_rootport_13018.

The DWC PCIe PMU driver registers a perf PMU driver, which provides

description of available events and configuration options in sysfs, see

/sys/bus/event_source/devices/dwc_rootport_{bdf}.

/sys/bus/event_source/devices/dwc_rootport_{sbdf}.

The "format" directory describes format of the config fields of the

perf_event_attr structure. The "events" directory provides configuration

    $# perf list | grep dwc_rootport

    <...>

    dwc_rootport_3018/Rx_PCIe_TLP_Data_Payload/        [Kernel PMU event]

    dwc_rootport_13018/Rx_PCIe_TLP_Data_Payload/        [Kernel PMU event]

    <...>

    dwc_rootport_3018/rx_memory_read,lane=?/               [Kernel PMU event]

    dwc_rootport_13018/rx_memory_read,lane=?/               [Kernel PMU event]

Time Based Analysis Event Usage

-------------------------------

Example usage of counting PCIe RX TLP data payload (Units of bytes)::

    $# perf stat -a -e dwc_rootport_3018/Rx_PCIe_TLP_Data_Payload/

    $# perf stat -a -e dwc_rootport_13018/Rx_PCIe_TLP_Data_Payload/

The average RX/TX bandwidth can be calculated using the following formula:

Each lane has the same event set and to avoid generating a list of hundreds

of events, the user need to specify the lane ID explicitly, e.g.::

    $# perf stat -a -e dwc_rootport_3018/rx_memory_read,lane=4/

    $# perf stat -a -e dwc_rootport_13018/rx_memory_read,lane=4/

The driver does not support sampling, therefore "perf record" will not

work. Per-task (without "-a") perf sessions are not supported.

PMU hardware device.

The "bus" sysfs file allows users to get the bus number of Root Ports

monitored by PMU.

monitored by PMU. Furthermore users can get the Root Ports range in

[bdf_min, bdf_max] from "bdf_min" and "bdf_max" sysfs attributes

respectively.

Example usage of perf::

   starfive_starlink_pmu

   arm-ccn

   arm-cmn

   arm-ni

   xgene-pmu

   arm_dsu_pmu

   thunderx2-pmu

      - arm,cmn-600

      - arm,cmn-650

      - arm,cmn-700

      - arm,cmn-s3

      - arm,ci-700

  reg: