Currently the tlb_remove_table_smp_sync IPI is sent to all CPUs indiscriminately, this causes unnecessary work and delays notable in real-time use-cases and isolated cpus. By limiting the IPI to only be sent to cpus referencing the effected mm and in kernel mode latency is improved. a config to differentiate architectures that support mm_cpumask from those that don't will allow safe usage of this feature. Yair Podemsky (3): arch: Introduce ARCH_HAS_CPUMASK_BITS mm/mmu_gather: send tlb_remove_table_smp_sync IPI only to MM CPUs mm/mmu_gather: send tlb_remove_table_smp_sync IPI only to CPUs in kernel mode -- 2.31.1