Backport the support for cluster scheduler level on Kunpeng Server · Pull Request !1417 · src-openEuler/kernel

#### 【关联issue】

#I4GEZS:[OpenEuler 20.03] Backport the support for cluster scheduler level on Kunpeng Server
#I88UKS:【OLK-5.10】修复cluster调度域建立错误的场景
#I5W44S:【OLK-5.10】sched/fair: Scan cluster before scanning LLC in wake-up path
The Kunpeng Server has cluster topology which was not supported by the mainline linux.
Now the support has been merged into mainline in v5.15.
https://lore.kernel.org/lkml/20210924085104.44806-1-21cnbao@gmail.com/

#### 【目标版本】
We'd like to backport the series to openEuler 20.03, in order to:
make scheduler build complete scheduler level on Kunpeng Server enhance the performance in some cases

#### 【PR介绍】
This PR has 4 series:
When the switch is turned off (kernel.sched_cluster=0 && UTIL-PROP=false), it does not affect the original schedule

1st series: make kernel aware of cluster, expose cluster to sysfs ABI and add SCHED_CLUSTER which can make load balance between clusters to benefit lots of workload. This has been merged into mainline:
https://lore.kernel.org/lkml/20210924085104.44806-1-21cnbao@gmail.com/

2nd series: Fix two bugs in cluster scheduler
The details of the 2 bugs can by find in the follow link:
#I88UKS:【OLK-5.10】修复cluster调度域建立错误的场景:【OLK-5.10】修复cluster调度域建立错误的场景

3rd series: This is the follow-up work to support cluster scheduler. Previously we have added cluster level in the scheduler for both ARM64[1] and X86[2] to support load balance between clusters to bring more memory bandwidth and decrease cache contention. This patchset, on the other hand, takes care of wake-up path by giving CPUs within the same cluster a try before scanning the whole LLC to benefit those tasks communicating with each other.

4rd series: Introduce SIS_UTIL to search idle CPU based on sum of util_avg to reduce time spent on select_idle_cpu().Under the arm64 platform, the UTIL feature is enabled by default and the PROP feature is turned off. On other platforms, the opposite is true.
0583e3fcc24f sched/fair: Fix kabi borken in sched_domain_shared
ee1d60d88443 sched/fair:ARM64 enables SIS_UTIL and disables SIS_PROP

| commitId     | 补丁名称 | 回合是否冲突 | 冲突原因 | 不使能是否影响原调度 | 原因 |
|--------------|---------|-------------|----------|--------|------|
| 1b13f2fb8f8b | topology: Represent clusters of CPUs within a die                              | 是 | Documentation的位置和格式发生变化。部分代码的相对位置发生变化 | 否 | 新增cluster结构 |
| 7bc2a89b5f48 | sched: Add cluster scheduler level in core and related Kconfig for ARM64       | 否 | | 否 | 新增cluster调度级别 |
| 9af57e69c315 | topology/sysfs: export cluster attributes only if an architectures has support | 是 |Documentaion的位置发生变化，按照4.19内核的原位置修改。部分代码发生重构，相对位置发生变化，基于4.19内核添加修改 |否 | 限制属性在已支持平台可用 |
| 70b392a77b54 | topology: Remove unused cpu_cluster_mask()                                     | 否 | |否 | 对9af57e69c315修改|
| 9c1386d3a2d2 | arch_topology: Limit span of cpu_clustergroup_mask()                           | 是 |	4.19内核到5.10内核存在重构，修改点所在的文件位置发生变化，基于4.19内核进行修改 |否 | 对1b13f2fb8f8b修改|
| 644d6533015e | arch_topology: Make cluster topology span at least SMT CPUs                    | 是 |代码所在的文件位置发生变化，按照4.19内核中的原位置修改 | 否 | 对9c1386d3a2d2修改 |
| b34a517d3516 | sched: Add per_cpu cluster domain info and cpus_share_lowest_cache API         | 是 |SD_CLUSTER的声明方式在4.19内核到5.10内核之间存在重构，这里使用4.19内核的声明方式 | 否 | 新增接口 |
| ee8485e1b79d | sched/fair: Scan cluster before scanning LLC in wake-up path                   | 是 |select_idle_cpu这个函数在4.19内核到5.10内核之间存在重构，这里基于4.19内核的函数，修改patch的内容 | 否 | 该特性在开关关闭时不生效 |
| 86ef1e50a2a6 | scheduler: Create SDTL_SKIP flag to skip topology level                        | 是 |当前4.19分支的CONFIG_SCHED_SMT默认为n，需要考虑sched_cluster作为调度域最低层级的情况|否 | 新增标签 |
| c288211ed996 | sysctl: add a new register_sysctl_init() interface                             | 是 |增加新的依赖patch引入，新增一个register_sysctl_init()接口，部分代码位置发生变化|否 | 新增接口 |
| de72c7e79c7f | sched/topology, drivers/base/arch_topology: Rebuild the sched_domain hierarchy when capacities change   | 是 |增加新的依赖patch，删除部分用不到的功能，仅引入topology_update_cpu_topology这个函数|否 | 新增接口 |
| 7a8dde1b4f0c | sched/topology, arch/arm64: Rebuild the sched_domain hierarchy when the CPU capacity changes            | 否 ||否 | 新增接口 |
| 559cd62adbc0 | scheduler: Add runtime knob sysctl_sched_cluster                               | 是 |部分代码的相对位置发生变化|否 | 添加运行时开关 |
| 4ab20861b0c0 | scheduler: Add boot time enabling/disabling of cluster scheduling              | ||否 | 添加启动时开关 |
| 51bf9d798b7d | scheduler: Disable cluster scheduling by default                               | ||否 | 默认关闭cluster调度 |
| 1940b3f5f8df | sched:Open the kernel configuration for cluster.                               | ||否 | 开启内核中cluster配置 |
| 35f72f3f2676 | sched/fair: Introduce SIS_UTIL to search idle CPU based on sum of util_avg     | 是|部分代码位置发生变化|否 | UTIL关闭时该特性不生效 |
| 0583e3fcc24f | sched/fair: Fix kabi borken in sched_domain_shared                             | 是|部分代码位置发生变化|否 |  |
| ee1d60d88443 | sched/fair:ARM64 enables SIS_UTIL and disables SIS_PROP                        | 是|部分代码位置发生变化|否 |  |

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