Re: [RFC v2] mm: add page preemption

[Kirill A. Shutemov]

On Sat, Oct 26, 2019 at 07:28:08PM +0800, Hillf Danton wrote:
> @@ -218,6 +219,9 @@ struct page {
>  
>  #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
>  	int _last_cpupid;
> +#else
> +	int prio;
> +#define CONFIG_PAGE_PREEMPTION PP
>  #endif
>  } _struct_page_alignment;
>  

No.

There's a really good reason we trying hard to push the _last_cpuid into
page flags instead of growing the struct page by 4 bytes.

I don't think your feature worth 0.1% of RAM and a lot of cache misses
that this change would generate.

-- 
 Kirill A. Shutemov