lkml.org 
[lkml]   [2018]   [Sep]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v2] memory_hotplug: Free pages as higher order
From
Date
On 9/25/18 7:42 AM, Arun KS wrote:
> When free pages are done with higher order, time spend on
> coalescing pages by buddy allocator can be reduced. With
> section size of 256MB, hot add latency of a single section
> shows improvement from 50-60 ms to less than 1 ms, hence
> improving the hot add latency by 60%.
>
> Modify external providers of online callback to align with
> the change.
>
> Signed-off-by: Arun KS <arunks@codeaurora.org>

Hi,

> @@ -655,26 +655,53 @@ void __online_page_free(struct page *page)
> }
> EXPORT_SYMBOL_GPL(__online_page_free);
>
> -static void generic_online_page(struct page *page)
> +static int generic_online_page(struct page *page, unsigned int order)
> {
> - __online_page_set_limits(page);
> - __online_page_increment_counters(page);
> - __online_page_free(page);
> + unsigned long nr_pages = 1 << order;
> + struct page *p = page;
> + unsigned int loop;
> +
> + for (loop = 0 ; loop < nr_pages ; loop++, p++) {
> + __ClearPageReserved(p);
> + set_page_count(p, 0);
> + }
> +
> + adjust_managed_page_count(page, nr_pages);
> + set_page_refcounted(page);
> + __free_pages(page, order);
> +
> + return 0;

This seems like almost complete copy of __free_pages_boot_core(), could
you do some code reuse instead? I think Michal Hocko also suggested that.

Thanks,
Vlastimil

\
 
 \ /
  Last update: 2018-09-25 11:59    [W:0.050 / U:0.384 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site