Re: [PATCH 1/4] mm: pass set_count and set_reserved to __init_single_page

David Hildenbrand
2023-09-22T07:50:00Z

On 22.09.23 09:47, Matthew Wilcox wrote:
> On Fri, Sep 22, 2023 at 03:09:20PM +0800, Yajun Deng wrote:
>> - __init_single_page(page, pfn, zone, nid);
>> + __init_single_page(page, pfn, zone, nid, true, false);
>
> So Linus has just had a big rant about not doing bool flags to
> functions. And in particular _multiple_ bool flags to functions.
>
> ie this should be:
>
> #define INIT_PAGE_COUNT (1 << 0)
> #define INIT_PAGE_RESERVED (1 << 1)
>
> __init_single_page(page, pfn, zone, nid, INIT_PAGE_COUNT);
>
> or something similar.
>
> I have no judgement on the merits of this patch so far. Do you have
> performance numbers for each of these patches? Some of them seem quite
> unlikely to actually help, at least on a machine which is constrained
> by cacheline fetches.

The last patch contains

before:
node 0 deferred pages initialised in 78ms

after:
node 0 deferred pages initialised in 72ms

Not earth-shattering :D Maybe with much bigger machines relevant?

--
Cheers,

David / dhildenb