Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 4738e1b9 authored by Jan Beulich's avatar Jan Beulich Committed by Linus Torvalds
Browse files

memory hotplug: fix updating of num_physpages for hot plugged memory 



Sizing of memory allocations shouldn't depend on the number of physical
pages found in a system, as that generally includes (perhaps a huge amount
of) non-RAM pages.  The amount of what actually is usable as storage
should instead be used as a basis here.

In line with that, the memory hotplug code should update num_physpages in
a way that it retains its original (post-boot) meaning; in particular,
decreasing the value should at best be done with great care - this patch
doesn't try to ever decrease this value at all as it doesn't really seem
meaningful to do so.

Signed-off-by: default avatarJan Beulich <jbeulich@novell.com>
Acked-by: default avatarRusty Russell <rusty@rustcorp.com.au>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 78986a67

mm/memory_hotplug.c

+4 −2
Original line number Diff line number Diff line
@@ -339,8 +339,11 @@ EXPORT_SYMBOL_GPL(__remove_pages); 


void online_page(struct page *page)

{

	unsigned long pfn = page_to_pfn(page);



	totalram_pages++;

	num_physpages++;

	if (pfn >= num_physpages)

		num_physpages = pfn + 1;



#ifdef CONFIG_HIGHMEM

	if (PageHighMem(page))
@@ -832,7 +835,6 @@ int offline_pages(unsigned long start_pfn, 
	zone->present_pages -= offlined_pages;

	zone->zone_pgdat->node_present_pages -= offlined_pages;

	totalram_pages -= offlined_pages;

	num_physpages -= offlined_pages;



	setup_per_zone_wmarks();

	calculate_zone_inactive_ratio(zone);