sched,x86: Don't use cluster topology for x86 hybrid CPUs

mainline inclusion
from mainline-v5.16-rc5
commit cabdc3a8
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I8LVOX


CVE: N/A

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Intel-SIG: commit cabdc3a8 sched,x86: Don't use cluster topology
for x86 hybrid CPUs.
Cluster scheduler feature backport.

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For x86 hybrid CPUs like Alder Lake, the order of CPU selection should
be based strictly on CPU priority.  Don't include cluster topology for
hybrid CPUs to avoid interference with such CPU selection order.

On Alder Lake, the Atom CPU cluster has more capacity (4 Atom CPUs) vs
Big core cluster (2 hyperthread CPUs). This could potentially bias CPU
selection towards Atom over Big Core, when Big core CPU has higher
priority.

Fixes: 66558b73 ("sched: Add cluster scheduler level for x86")
Suggested-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Tim Chen <tim.c.chen@linux.intel.com>
Tested-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Link: https://lkml.kernel.org/r/20211204091402.GM16608@worktop.programming.kicks-ass.net


Signed-off-by: Aubrey Li <aubrey.li@linux.intel.com>