mm/page_alloc.c: memory hotplug: free pages as higher order
When freeing pages are done with higher order, time spent 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 times. Modify
external providers of online callback to align with the change.
[[email protected]: v11]
Link: http://lkml.kernel.org/r/[email protected]
[[email protected]: remove unused local, per Arun]
[[email protected]: avoid return of void-returning __free_pages_core(), per Oscar]
[[email protected]: fix it for mm-convert-totalram_pages-and-totalhigh_pages-variables-to-atomic.patch]
[[email protected]: v8]
Link: http://lkml.kernel.org/r/[email protected]
[[email protected]: v9]
Link: http://lkml.kernel.org/r/[email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arun KS <[email protected]>
Reviewed-by: Andrew Morton <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Reviewed-by: Oscar Salvador <[email protected]>
Reviewed-by: Alexander Duyck <[email protected]>
Cc: K. Y. Srinivasan <[email protected]>
Cc: Haiyang Zhang <[email protected]>
Cc: Stephen Hemminger <[email protected]>
Cc: Boris Ostrovsky <[email protected]>
Cc: Juergen Gross <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Mathieu Malaterre <[email protected]>
Cc: "Kirill A. Shutemov" <[email protected]>
Cc: Souptick Joarder <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Aaron Lu <[email protected]>
Cc: Srivatsa Vaddagiri <[email protected]>
Cc: Vinayak Menon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 368267c..52869d6 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -89,7 +89,7 @@ extern int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn,
unsigned long *valid_start, unsigned long *valid_end);
extern void __offline_isolated_pages(unsigned long, unsigned long);
-typedef void (*online_page_callback_t)(struct page *page);
+typedef void (*online_page_callback_t)(struct page *page, unsigned int order);
extern int set_online_page_callback(online_page_callback_t callback);
extern int restore_online_page_callback(online_page_callback_t callback);
