Re: Excessive TLB flush ranges

Thomas Gleixner
2023-05-16T08:18:42Z

On Tue, May 16 2023 at 08:37, Thomas Gleixner wrote:
> On Mon, May 15 2023 at 22:31, Russell King wrote:
>>> + list_for_each_entry(va, list, list) {
>>> + /* flush range by one by one 'invlpg' */
>>> + for (addr = va->va_start; addr < va->va_end; addr += PAGE_SIZE)
>>> + flush_tlb_one_kernel(addr);
>>
>> Isn't this just the same as:
>> flush_tlb_kernel_range(va->va_start, va->va_end);
>
> Indeed.

Actually not. At least not on x86 where it'd end up with 3 IPIs for that
case again, instead of having one which walks the list on each CPU.

Thanks,

tglx