Re: [PATCH v5 10/12] x86,tlb: do targeted broadcast flushing from tlbbatch code

Rik van Riel
2025-01-21T02:34:01Z

On Mon, 2025-01-20 at 20:56 +0200, Nadav Amit wrote:
>
> Then in switch_mm_irqs_off(), b
>
> if (this_cpu_read(cpu_tlbstate.pending_tlbsync))
> tlbsync();
>
> Note that when switch_mm_irqs_off() is called due to context switch
> from
> context_switch(), finish_task_switch() has still not took place, so
> the
> task cannot be scheduled on other cores.
>
>
That would certainly work.

I'll add that as a separate patch, which the x86
maintainers can either accept or leave out.

I'm not sure what's worse, making reclaim non-migratable,
or adding an extra branch (we can probably avoid a cache
line miss) to switch_mm_irqs_off.

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