From d91749c1dda71a7030c054a5ab8dc5419bc6730b Mon Sep 17 00:00:00 2001 From: Taku Izumi Date: Tue, 15 Mar 2016 14:55:18 -0700 Subject: [PATCH] mm/page_alloc.c: calculate zone_start_pfn at zone_spanned_pages_in_node() Xeon E7 v3 based systems supports Address Range Mirroring and UEFI BIOS complied with UEFI spec 2.5 can notify which ranges are mirrored (reliable) via EFI memory map. Now Linux kernel utilize its information and allocates boot time memory from reliable region. My requirement is: - allocate kernel memory from mirrored region - allocate user memory from non-mirrored region In order to meet my requirement, ZONE_MOVABLE is useful. By arranging non-mirrored range into ZONE_MOVABLE, mirrored memory is used for kernel allocations. My idea is to extend existing "kernelcore" option and introduces kernelcore=mirror option. By specifying "mirror" instead of specifying the amount of memory, non-mirrored region will be arranged into ZONE_MOVABLE. Earlier discussions are at: https://lkml.org/lkml/2015/10/9/24 https://lkml.org/lkml/2015/10/15/9 https://lkml.org/lkml/2015/11/27/18 https://lkml.org/lkml/2015/12/8/836 For example, suppose 2-nodes system with the following memory range: node 0 [mem 0x0000000000001000-0x000000109fffffff] node 1 [mem 0x00000010a0000000-0x000000209fffffff] and the following ranges are marked as reliable (mirrored): [0x0000000000000000-0x0000000100000000] [0x0000000100000000-0x0000000180000000] [0x0000000800000000-0x0000000880000000] [0x00000010a0000000-0x0000001120000000] [0x00000017a0000000-0x0000001820000000] If you specify kernelcore=mirror, ZONE_NORMAL and ZONE_MOVABLE are arranged like bellow: - node 0: ZONE_NORMAL : [0x0000000100000000-0x00000010a0000000] ZONE_MOVABLE: [0x0000000180000000-0x00000010a0000000] - node 1: ZONE_NORMAL : [0x00000010a0000000-0x00000020a0000000] ZONE_MOVABLE: [0x0000001120000000-0x00000020a0000000] In overlapped range, pages to be ZONE_MOVABLE in ZONE_NORMAL are treated as absent pages, and vice versa. This patch (of 2): Currently each zone's zone_start_pfn is calculated at free_area_init_core(). However zone's range is fixed at the time when invoking zone_spanned_pages_in_node(). This patch changes how each zone->zone_start_pfn is calculated in zone_spanned_pages_in_node(). Signed-off-by: Taku Izumi Cc: Tony Luck Cc: Xishi Qiu Cc: KAMEZAWA Hiroyuki Cc: Mel Gorman Cc: Dave Hansen Cc: Matt Fleming Cc: Arnd Bergmann Cc: Steve Capper Cc: Sudeep Holla Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_alloc.c | 40 +++++++++++++++++++++++++++++----------- 1 file changed, 29 insertions(+), 11 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 838ca8bb64f7..0d20a19151a4 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -4953,31 +4953,31 @@ static unsigned long __meminit zone_spanned_pages_in_node(int nid, unsigned long zone_type, unsigned long node_start_pfn, unsigned long node_end_pfn, + unsigned long *zone_start_pfn, + unsigned long *zone_end_pfn, unsigned long *ignored) { - unsigned long zone_start_pfn, zone_end_pfn; - /* When hotadd a new node from cpu_up(), the node should be empty */ if (!node_start_pfn && !node_end_pfn) return 0; /* Get the start and end of the zone */ - zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type]; - zone_end_pfn = arch_zone_highest_possible_pfn[zone_type]; + *zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type]; + *zone_end_pfn = arch_zone_highest_possible_pfn[zone_type]; adjust_zone_range_for_zone_movable(nid, zone_type, node_start_pfn, node_end_pfn, - &zone_start_pfn, &zone_end_pfn); + zone_start_pfn, zone_end_pfn); /* Check that this node has pages within the zone's required range */ - if (zone_end_pfn < node_start_pfn || zone_start_pfn > node_end_pfn) + if (*zone_end_pfn < node_start_pfn || *zone_start_pfn > node_end_pfn) return 0; /* Move the zone boundaries inside the node if necessary */ - zone_end_pfn = min(zone_end_pfn, node_end_pfn); - zone_start_pfn = max(zone_start_pfn, node_start_pfn); + *zone_end_pfn = min(*zone_end_pfn, node_end_pfn); + *zone_start_pfn = max(*zone_start_pfn, node_start_pfn); /* Return the spanned pages */ - return zone_end_pfn - zone_start_pfn; + return *zone_end_pfn - *zone_start_pfn; } /* @@ -5042,8 +5042,18 @@ static inline unsigned long __meminit zone_spanned_pages_in_node(int nid, unsigned long zone_type, unsigned long node_start_pfn, unsigned long node_end_pfn, + unsigned long *zone_start_pfn, + unsigned long *zone_end_pfn, unsigned long *zones_size) { + unsigned int zone; + + *zone_start_pfn = node_start_pfn; + for (zone = 0; zone < zone_type; zone++) + *zone_start_pfn += zones_size[zone]; + + *zone_end_pfn = *zone_start_pfn + zones_size[zone_type]; + return zones_size[zone_type]; } @@ -5072,15 +5082,22 @@ static void __meminit calculate_node_totalpages(struct pglist_data *pgdat, for (i = 0; i < MAX_NR_ZONES; i++) { struct zone *zone = pgdat->node_zones + i; + unsigned long zone_start_pfn, zone_end_pfn; unsigned long size, real_size; size = zone_spanned_pages_in_node(pgdat->node_id, i, node_start_pfn, node_end_pfn, + &zone_start_pfn, + &zone_end_pfn, zones_size); real_size = size - zone_absent_pages_in_node(pgdat->node_id, i, node_start_pfn, node_end_pfn, zholes_size); + if (size) + zone->zone_start_pfn = zone_start_pfn; + else + zone->zone_start_pfn = 0; zone->spanned_pages = size; zone->present_pages = real_size; @@ -5201,7 +5218,6 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat) { enum zone_type j; int nid = pgdat->node_id; - unsigned long zone_start_pfn = pgdat->node_start_pfn; int ret; pgdat_resize_init(pgdat); @@ -5222,6 +5238,7 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat) for (j = 0; j < MAX_NR_ZONES; j++) { struct zone *zone = pgdat->node_zones + j; unsigned long size, realsize, freesize, memmap_pages; + unsigned long zone_start_pfn = zone->zone_start_pfn; size = zone->spanned_pages; realsize = freesize = zone->present_pages; @@ -5290,7 +5307,6 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat) ret = init_currently_empty_zone(zone, zone_start_pfn, size); BUG_ON(ret); memmap_init(size, nid, j, zone_start_pfn); - zone_start_pfn += size; } } @@ -5358,6 +5374,8 @@ void __paginginit free_area_init_node(int nid, unsigned long *zones_size, pr_info("Initmem setup node %d [mem %#018Lx-%#018Lx]\n", nid, (u64)start_pfn << PAGE_SHIFT, end_pfn ? ((u64)end_pfn << PAGE_SHIFT) - 1 : 0); +#else + start_pfn = node_start_pfn; #endif calculate_node_totalpages(pgdat, start_pfn, end_pfn, zones_size, zholes_size); -- 2.20.1