[PATCH 2/4] mm: rmap: Allow platforms without mm_cpumask to defer TLB flush

[Peter Zijlstra]

On Fri, Jul 08, 2022 at 08:08:45AM +0000, Nadav Amit wrote:

> Is it really only x86 that has mm_cpumask()?

Unlikely, everybody who needs to IPI (eg. doesn't have broadcast
invalidate) has benefit to track this mask more accurately.

The below greps for clearing CPUs in the mask and ought to be a fair
indicator:

$ git grep -l "cpumask_clear_cpu.*mm_cpumask" arch/
arch/arm/include/asm/mmu_context.h
arch/loongarch/include/asm/mmu_context.h
arch/loongarch/mm/tlb.c
arch/mips/include/asm/mmu_context.h
arch/openrisc/mm/tlb.c
arch/powerpc/include/asm/book3s/64/mmu.h
arch/powerpc/mm/book3s64/radix_tlb.c
arch/riscv/mm/context.c
arch/s390/kernel/smp.c
arch/um/include/asm/mmu_context.h
arch/x86/mm/tlb.c