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    Subject[PATCH 0/4] arch_topology: Updates to add socket support and fix cluster ids
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    Hi All,

    This series intends to fix some discrepancies we have in the CPU topology
    parsing from the device tree /cpu-map node. Also this diverges from the
    behaviour on a ACPI enabled platform. The expectation is that both DT
    and ACPI enabled systems must present consistent view of the CPU topology.

    Currently we assign generated cluster count as the physical package identifier
    for each CPU which is wrong. The device tree bindings for CPU topology supports
    sockets to infer the socket or physical package identifier for a given CPU.
    Also we don't check if all the cores/threads belong to the same cluster before
    updating their sibling masks which is fine as we don't set the cluster id yet.

    These changes also assigns the cluster identifier as parsed from the device tree
    cluster nodes within /cpu-map without support for nesting of the clusters.
    Finally, it also add support for socket nodes in /cpu-map. With this the
    parsing of exact same information from ACPI PPTT and /cpu-map DT node
    aligns well.

    The only exception is that the last level cache id information can be
    inferred from the same ACPI PPTT while we need to parse CPU cache nodes
    in the device tree. llc_id is not handled as part of these changes.

    P.S: I have not cc-ed Greg and Rafael so that all the users of arch_topology
    agree with the changes first before we include them.

    Sudeep Holla (4):
    arch_topology: Don't set cluster identifier as physical package identifier
    arch_topology: Set thread and core siblings only within the cluster
    arch_topology: Set cluster identifier in each core/thread from /cpu-map
    arch_topology: Add support for parsing sockets in /cpu-map

    drivers/base/arch_topology.c | 48 +++++++++++++++++++++++++++---------
    1 file changed, 37 insertions(+), 11 deletions(-)

    --
    2.36.1

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