memmap_init_zone() loops through every Page Frame Number (pfn), including pfn values that are within the gaps between existing memory sections. The unneeded looping will become a boot performance issue when machines configure larger memory ranges that will contain larger and more numerous gaps.
The code will skip across invalid pfn values to reduce the number of loops executed. Signed-off-by: Mike Yoknis <[email protected]> --- mm/page_alloc.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 45c916b..9f9c1a6 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3857,8 +3857,11 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, * exist on hotplugged memory. */ if (context == MEMMAP_EARLY) { - if (!early_pfn_valid(pfn)) + if (!early_pfn_valid(pfn)) { + pfn = ALIGN(pfn + MAX_ORDER_NR_PAGES, + MAX_ORDER_NR_PAGES) - 1; continue; + } if (!early_pfn_in_nid(pfn, nid)) continue; } -- 1.7.11.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
