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x86/sched/itmt: Give all SMT siblings of a core the same priority

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X86 does not have the SD_ASYM_PACKING flag in the SMT domain. The scheduler
knows how to handle SMT and non-SMT cores of different priority. There is
no reason for SMT siblings of a core to have different priorities.

Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Len Brown <len.brown@intel.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Link: https://lore.kernel.org/r/20230406203148.19182-12-ricardo.neri-calderon@linux.intel.com
This commit is contained in:
Ricardo Neri 2023-04-06 13:31:47 -07:00 committed by Peter Zijlstra
parent 995998ebde
commit 046a5a95c3
1 changed files with 5 additions and 18 deletions
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23
arch/x86/kernel/itmt.c
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@ -165,32 +165,19 @@ int arch_asym_cpu_priority(int cpu)
/**
* sched_set_itmt_core_prio() - Set CPU priority based on ITMT
* @prio: Priority of cpu core
* @core_cpu: The cpu number associated with the core
* @prio: Priority of @cpu
* @cpu: The CPU number
*
* The pstate driver will find out the max boost frequency
* and call this function to set a priority proportional
* to the max boost frequency. CPU with higher boost
* to the max boost frequency. CPUs with higher boost
* frequency will receive higher priority.
*
* No need to rebuild sched domain after updating
* the CPU priorities. The sched domains have no
* dependency on CPU priorities.
*/
void sched_set_itmt_core_prio(int prio, int core_cpu)
void sched_set_itmt_core_prio(int prio, int cpu)
{
int cpu, i = 1;
for_each_cpu(cpu, topology_sibling_cpumask(core_cpu)) {
int smt_prio;
/*
* Ensure that the siblings are moved to the end
* of the priority chain and only used when
* all other high priority cpus are out of capacity.
*/
smt_prio = prio * smp_num_siblings / (i * i);
per_cpu(sched_core_priority, cpu) = smt_prio;
i++;
}
per_cpu(sched_core_priority, cpu) = prio;
}