PR sync from: Yushan Wang wangyushan12@huawei.com
https://mailweb.openeuler.org/archives/list/kernel@openeuler.org/message/43QJUBS62GUQOU6UGKR4CEKUBE3QBFEH/
From: Hongye Lin linhongye@h-partners.com

driver inclusion
category: feature
bugzilla: #IBAZ3A:【OLK-6.6】kabi reserver space for i2c and sched

The core CPU control framework supports runtime SMT control which
is not yet supported on arm64. Besides the general vulnerabilities
concerns we want this runtime control on our arm64 server for:

• better single CPU performance in some cases
• saving overall power consumption

This patchset implements it in the following aspects:

• Provides a default topology_is_primary_thread()
• support retrieve SMT thread number on OF based system
• support retrieve SMT thread number on ACPI based system
• select HOTPLUG_SMT for arm64

Tests has been done on our ACPI based arm64 server and on ACPI/OF
based QEMU VMs.

Yicong Yang (5):
Revert "arm64: Kconfig: Enable HOTPLUG_SMT"
cpu/SMT: Provide a default topology_is_primary_thread()
arch_topology: Support SMT control for OF based system
arm64: topology: Support SMT control on ACPI based system
arm64: Kconfig: Enable HOTPLUG_SMT

#IBAZ3A:【OLK-6.6】kabi reserver space for i2c and sched