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drivers: base: cacheinfo: Get rid of DEFINE_SMP_CALL_CACHE_FUNCTION()

Vitaly Kuznetsov requested to merge vkuznets/centos-stream-9:bug2031644 into main

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2031644

commit 4b92d4add5f6dcf21275185c997d6ecb800054cd
Author: Thomas Gleixner <tglx@linutronix.de>
Date:   Tue Aug 31 13:48:34 2021 +0200

    drivers: base: cacheinfo: Get rid of DEFINE_SMP_CALL_CACHE_FUNCTION()

    DEFINE_SMP_CALL_CACHE_FUNCTION() was usefel before the CPU hotplug rework
    to ensure that the cache related functions are called on the upcoming CPU
    because the notifier itself could run on any online CPU.

    The hotplug state machine guarantees that the callbacks are invoked on the
    upcoming CPU. So there is no need to have this SMP function call
    obfuscation. That indirection was missed when the hotplug notifiers were
    converted.

    This also solves the problem of ARM64 init_cache_level() invoking ACPI
    functions which take a semaphore in that context. That's invalid as SMP
    function calls run with interrupts disabled. Running it just from the
    callback in context of the CPU hotplug thread solves this.

    Fixes: 8571890e1513 ("arm64: Add support for ACPI based firmware tables")
    Reported-by: Guenter Roeck <linux@roeck-us.net>
    Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
    Tested-by: Guenter Roeck <linux@roeck-us.net>
    Acked-by: Will Deacon <will@kernel.org>
    Acked-by: Peter Zijlstra <peterz@infradead.org>
    Link: https://lore.kernel.org/r/871r69ersb.ffs@tglx

Signed-off-by: Vitaly Kuznetsov vkuznets@redhat.com

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