kernel-ark/arch/ia64/mm/discontig.c
Robin Holt fde740e4dd [IA64] Percpu quicklist for combined allocator for pgd/pmd/pte.
This patch introduces using the quicklists for pgd, pmd, and pte levels
by combining the alloc and free functions into a common set of routines.
This greatly simplifies the reading of this header file.

This patch is simple but necessary for large numa configurations.
It simply ensures that only pages from the local node are added to a
cpus quicklist.  This prevents the trapping of pages on a remote nodes
quicklist by starting a process, touching a large number of pages to
fill pmd and pte entries, migrating to another node, and then unmapping
or exiting.  With those conditions, the pages get trapped and if the
machine has more than 100 nodes of the same size, the calculation of
the pgtable high water mark will be larger than any single node so page
table cache flushing will never occur.

I ran lmbench lat_proc fork and lat_proc exec on a zx1 with and without
this patch and did not notice any change.

On an sn2 machine, there was a slight improvement which is possibly
due to pages from other nodes trapped on the test node before starting
the run.  I did not investigate further.

This patch shrinks the quicklist based upon free memory on the node
instead of the high/low water marks.  I have written it to enable
preemption periodically and recalculate the amount to shrink every time
we have freed enough pages that the quicklist size should have grown.
I rescan the nodes zones each pass because other processess may be
draining node memory at the same time as we are adding.

Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-04-25 13:13:16 -07:00

739 lines
21 KiB
C

/*
* Copyright (c) 2000, 2003 Silicon Graphics, Inc. All rights reserved.
* Copyright (c) 2001 Intel Corp.
* Copyright (c) 2001 Tony Luck <tony.luck@intel.com>
* Copyright (c) 2002 NEC Corp.
* Copyright (c) 2002 Kimio Suganuma <k-suganuma@da.jp.nec.com>
* Copyright (c) 2004 Silicon Graphics, Inc
* Russ Anderson <rja@sgi.com>
* Jesse Barnes <jbarnes@sgi.com>
* Jack Steiner <steiner@sgi.com>
*/
/*
* Platform initialization for Discontig Memory
*/
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/bootmem.h>
#include <linux/acpi.h>
#include <linux/efi.h>
#include <linux/nodemask.h>
#include <asm/pgalloc.h>
#include <asm/tlb.h>
#include <asm/meminit.h>
#include <asm/numa.h>
#include <asm/sections.h>
/*
* Track per-node information needed to setup the boot memory allocator, the
* per-node areas, and the real VM.
*/
struct early_node_data {
struct ia64_node_data *node_data;
pg_data_t *pgdat;
unsigned long pernode_addr;
unsigned long pernode_size;
struct bootmem_data bootmem_data;
unsigned long num_physpages;
unsigned long num_dma_physpages;
unsigned long min_pfn;
unsigned long max_pfn;
};
static struct early_node_data mem_data[MAX_NUMNODES] __initdata;
/**
* reassign_cpu_only_nodes - called from find_memory to move CPU-only nodes to a memory node
*
* This function will move nodes with only CPUs (no memory)
* to a node with memory which is at the minimum numa_slit distance.
* Any reassigments will result in the compression of the nodes
* and renumbering the nid values where appropriate.
* The static declarations below are to avoid large stack size which
* makes the code not re-entrant.
*/
static void __init reassign_cpu_only_nodes(void)
{
struct node_memblk_s *p;
int i, j, k, nnode, nid, cpu, cpunid, pxm;
u8 cslit, slit;
static DECLARE_BITMAP(nodes_with_mem, MAX_NUMNODES) __initdata;
static u8 numa_slit_fix[MAX_NUMNODES * MAX_NUMNODES] __initdata;
static int node_flip[MAX_NUMNODES] __initdata;
static int old_nid_map[NR_CPUS] __initdata;
for (nnode = 0, p = &node_memblk[0]; p < &node_memblk[num_node_memblks]; p++)
if (!test_bit(p->nid, (void *) nodes_with_mem)) {
set_bit(p->nid, (void *) nodes_with_mem);
nnode++;
}
/*
* All nids with memory.
*/
if (nnode == num_online_nodes())
return;
/*
* Change nids and attempt to migrate CPU-only nodes
* to the best numa_slit (closest neighbor) possible.
* For reassigned CPU nodes a nid can't be arrived at
* until after this loop because the target nid's new
* identity might not have been established yet. So
* new nid values are fabricated above num_online_nodes() and
* mapped back later to their true value.
*/
/* MCD - This code is a bit complicated, but may be unnecessary now.
* We can now handle much more interesting node-numbering.
* The old requirement that 0 <= nid <= numnodes <= MAX_NUMNODES
* and that there be no holes in the numbering 0..numnodes
* has become simply 0 <= nid <= MAX_NUMNODES.
*/
nid = 0;
for_each_online_node(i) {
if (test_bit(i, (void *) nodes_with_mem)) {
/*
* Save original nid value for numa_slit
* fixup and node_cpuid reassignments.
*/
node_flip[nid] = i;
if (i == nid) {
nid++;
continue;
}
for (p = &node_memblk[0]; p < &node_memblk[num_node_memblks]; p++)
if (p->nid == i)
p->nid = nid;
cpunid = nid;
nid++;
} else
cpunid = MAX_NUMNODES;
for (cpu = 0; cpu < NR_CPUS; cpu++)
if (node_cpuid[cpu].nid == i) {
/*
* For nodes not being reassigned just
* fix the cpu's nid and reverse pxm map
*/
if (cpunid < MAX_NUMNODES) {
pxm = nid_to_pxm_map[i];
pxm_to_nid_map[pxm] =
node_cpuid[cpu].nid = cpunid;
continue;
}
/*
* For nodes being reassigned, find best node by
* numa_slit information and then make a temporary
* nid value based on current nid and num_online_nodes().
*/
slit = 0xff;
k = 2*num_online_nodes();
for_each_online_node(j) {
if (i == j)
continue;
else if (test_bit(j, (void *) nodes_with_mem)) {
cslit = numa_slit[i * num_online_nodes() + j];
if (cslit < slit) {
k = num_online_nodes() + j;
slit = cslit;
}
}
}
/* save old nid map so we can update the pxm */
old_nid_map[cpu] = node_cpuid[cpu].nid;
node_cpuid[cpu].nid = k;
}
}
/*
* Fixup temporary nid values for CPU-only nodes.
*/
for (cpu = 0; cpu < NR_CPUS; cpu++)
if (node_cpuid[cpu].nid == (2*num_online_nodes())) {
pxm = nid_to_pxm_map[old_nid_map[cpu]];
pxm_to_nid_map[pxm] = node_cpuid[cpu].nid = nnode - 1;
} else {
for (i = 0; i < nnode; i++) {
if (node_flip[i] != (node_cpuid[cpu].nid - num_online_nodes()))
continue;
pxm = nid_to_pxm_map[old_nid_map[cpu]];
pxm_to_nid_map[pxm] = node_cpuid[cpu].nid = i;
break;
}
}
/*
* Fix numa_slit by compressing from larger
* nid array to reduced nid array.
*/
for (i = 0; i < nnode; i++)
for (j = 0; j < nnode; j++)
numa_slit_fix[i * nnode + j] =
numa_slit[node_flip[i] * num_online_nodes() + node_flip[j]];
memcpy(numa_slit, numa_slit_fix, sizeof (numa_slit));
nodes_clear(node_online_map);
for (i = 0; i < nnode; i++)
node_set_online(i);
return;
}
/*
* To prevent cache aliasing effects, align per-node structures so that they
* start at addresses that are strided by node number.
*/
#define NODEDATA_ALIGN(addr, node) \
((((addr) + 1024*1024-1) & ~(1024*1024-1)) + (node)*PERCPU_PAGE_SIZE)
/**
* build_node_maps - callback to setup bootmem structs for each node
* @start: physical start of range
* @len: length of range
* @node: node where this range resides
*
* We allocate a struct bootmem_data for each piece of memory that we wish to
* treat as a virtually contiguous block (i.e. each node). Each such block
* must start on an %IA64_GRANULE_SIZE boundary, so we round the address down
* if necessary. Any non-existent pages will simply be part of the virtual
* memmap. We also update min_low_pfn and max_low_pfn here as we receive
* memory ranges from the caller.
*/
static int __init build_node_maps(unsigned long start, unsigned long len,
int node)
{
unsigned long cstart, epfn, end = start + len;
struct bootmem_data *bdp = &mem_data[node].bootmem_data;
epfn = GRANULEROUNDUP(end) >> PAGE_SHIFT;
cstart = GRANULEROUNDDOWN(start);
if (!bdp->node_low_pfn) {
bdp->node_boot_start = cstart;
bdp->node_low_pfn = epfn;
} else {
bdp->node_boot_start = min(cstart, bdp->node_boot_start);
bdp->node_low_pfn = max(epfn, bdp->node_low_pfn);
}
min_low_pfn = min(min_low_pfn, bdp->node_boot_start>>PAGE_SHIFT);
max_low_pfn = max(max_low_pfn, bdp->node_low_pfn);
return 0;
}
/**
* early_nr_phys_cpus_node - return number of physical cpus on a given node
* @node: node to check
*
* Count the number of physical cpus on @node. These are cpus that actually
* exist. We can't use nr_cpus_node() yet because
* acpi_boot_init() (which builds the node_to_cpu_mask array) hasn't been
* called yet.
*/
static int early_nr_phys_cpus_node(int node)
{
int cpu, n = 0;
for (cpu = 0; cpu < NR_CPUS; cpu++)
if (node == node_cpuid[cpu].nid)
if ((cpu == 0) || node_cpuid[cpu].phys_id)
n++;
return n;
}
/**
* early_nr_cpus_node - return number of cpus on a given node
* @node: node to check
*
* Count the number of cpus on @node. We can't use nr_cpus_node() yet because
* acpi_boot_init() (which builds the node_to_cpu_mask array) hasn't been
* called yet. Note that node 0 will also count all non-existent cpus.
*/
static int early_nr_cpus_node(int node)
{
int cpu, n = 0;
for (cpu = 0; cpu < NR_CPUS; cpu++)
if (node == node_cpuid[cpu].nid)
n++;
return n;
}
/**
* find_pernode_space - allocate memory for memory map and per-node structures
* @start: physical start of range
* @len: length of range
* @node: node where this range resides
*
* This routine reserves space for the per-cpu data struct, the list of
* pg_data_ts and the per-node data struct. Each node will have something like
* the following in the first chunk of addr. space large enough to hold it.
*
* ________________________
* | |
* |~~~~~~~~~~~~~~~~~~~~~~~~| <-- NODEDATA_ALIGN(start, node) for the first
* | PERCPU_PAGE_SIZE * | start and length big enough
* | cpus_on_this_node | Node 0 will also have entries for all non-existent cpus.
* |------------------------|
* | local pg_data_t * |
* |------------------------|
* | local ia64_node_data |
* |------------------------|
* | ??? |
* |________________________|
*
* Once this space has been set aside, the bootmem maps are initialized. We
* could probably move the allocation of the per-cpu and ia64_node_data space
* outside of this function and use alloc_bootmem_node(), but doing it here
* is straightforward and we get the alignments we want so...
*/
static int __init find_pernode_space(unsigned long start, unsigned long len,
int node)
{
unsigned long epfn, cpu, cpus, phys_cpus;
unsigned long pernodesize = 0, pernode, pages, mapsize;
void *cpu_data;
struct bootmem_data *bdp = &mem_data[node].bootmem_data;
epfn = (start + len) >> PAGE_SHIFT;
pages = bdp->node_low_pfn - (bdp->node_boot_start >> PAGE_SHIFT);
mapsize = bootmem_bootmap_pages(pages) << PAGE_SHIFT;
/*
* Make sure this memory falls within this node's usable memory
* since we may have thrown some away in build_maps().
*/
if (start < bdp->node_boot_start || epfn > bdp->node_low_pfn)
return 0;
/* Don't setup this node's local space twice... */
if (mem_data[node].pernode_addr)
return 0;
/*
* Calculate total size needed, incl. what's necessary
* for good alignment and alias prevention.
*/
cpus = early_nr_cpus_node(node);
phys_cpus = early_nr_phys_cpus_node(node);
pernodesize += PERCPU_PAGE_SIZE * cpus;
pernodesize += node * L1_CACHE_BYTES;
pernodesize += L1_CACHE_ALIGN(sizeof(pg_data_t));
pernodesize += L1_CACHE_ALIGN(sizeof(struct ia64_node_data));
pernodesize = PAGE_ALIGN(pernodesize);
pernode = NODEDATA_ALIGN(start, node);
/* Is this range big enough for what we want to store here? */
if (start + len > (pernode + pernodesize + mapsize)) {
mem_data[node].pernode_addr = pernode;
mem_data[node].pernode_size = pernodesize;
memset(__va(pernode), 0, pernodesize);
cpu_data = (void *)pernode;
pernode += PERCPU_PAGE_SIZE * cpus;
pernode += node * L1_CACHE_BYTES;
mem_data[node].pgdat = __va(pernode);
pernode += L1_CACHE_ALIGN(sizeof(pg_data_t));
mem_data[node].node_data = __va(pernode);
pernode += L1_CACHE_ALIGN(sizeof(struct ia64_node_data));
mem_data[node].pgdat->bdata = bdp;
pernode += L1_CACHE_ALIGN(sizeof(pg_data_t));
/*
* Copy the static per-cpu data into the region we
* just set aside and then setup __per_cpu_offset
* for each CPU on this node.
*/
for (cpu = 0; cpu < NR_CPUS; cpu++) {
if (node == node_cpuid[cpu].nid) {
memcpy(__va(cpu_data), __phys_per_cpu_start,
__per_cpu_end - __per_cpu_start);
__per_cpu_offset[cpu] = (char*)__va(cpu_data) -
__per_cpu_start;
cpu_data += PERCPU_PAGE_SIZE;
}
}
}
return 0;
}
/**
* free_node_bootmem - free bootmem allocator memory for use
* @start: physical start of range
* @len: length of range
* @node: node where this range resides
*
* Simply calls the bootmem allocator to free the specified ranged from
* the given pg_data_t's bdata struct. After this function has been called
* for all the entries in the EFI memory map, the bootmem allocator will
* be ready to service allocation requests.
*/
static int __init free_node_bootmem(unsigned long start, unsigned long len,
int node)
{
free_bootmem_node(mem_data[node].pgdat, start, len);
return 0;
}
/**
* reserve_pernode_space - reserve memory for per-node space
*
* Reserve the space used by the bootmem maps & per-node space in the boot
* allocator so that when we actually create the real mem maps we don't
* use their memory.
*/
static void __init reserve_pernode_space(void)
{
unsigned long base, size, pages;
struct bootmem_data *bdp;
int node;
for_each_online_node(node) {
pg_data_t *pdp = mem_data[node].pgdat;
bdp = pdp->bdata;
/* First the bootmem_map itself */
pages = bdp->node_low_pfn - (bdp->node_boot_start>>PAGE_SHIFT);
size = bootmem_bootmap_pages(pages) << PAGE_SHIFT;
base = __pa(bdp->node_bootmem_map);
reserve_bootmem_node(pdp, base, size);
/* Now the per-node space */
size = mem_data[node].pernode_size;
base = __pa(mem_data[node].pernode_addr);
reserve_bootmem_node(pdp, base, size);
}
}
/**
* initialize_pernode_data - fixup per-cpu & per-node pointers
*
* Each node's per-node area has a copy of the global pg_data_t list, so
* we copy that to each node here, as well as setting the per-cpu pointer
* to the local node data structure. The active_cpus field of the per-node
* structure gets setup by the platform_cpu_init() function later.
*/
static void __init initialize_pernode_data(void)
{
int cpu, node;
pg_data_t *pgdat_list[MAX_NUMNODES];
for_each_online_node(node)
pgdat_list[node] = mem_data[node].pgdat;
/* Copy the pg_data_t list to each node and init the node field */
for_each_online_node(node) {
memcpy(mem_data[node].node_data->pg_data_ptrs, pgdat_list,
sizeof(pgdat_list));
}
/* Set the node_data pointer for each per-cpu struct */
for (cpu = 0; cpu < NR_CPUS; cpu++) {
node = node_cpuid[cpu].nid;
per_cpu(cpu_info, cpu).node_data = mem_data[node].node_data;
}
}
/**
* find_memory - walk the EFI memory map and setup the bootmem allocator
*
* Called early in boot to setup the bootmem allocator, and to
* allocate the per-cpu and per-node structures.
*/
void __init find_memory(void)
{
int node;
reserve_memory();
if (num_online_nodes() == 0) {
printk(KERN_ERR "node info missing!\n");
node_set_online(0);
}
min_low_pfn = -1;
max_low_pfn = 0;
if (num_online_nodes() > 1)
reassign_cpu_only_nodes();
/* These actually end up getting called by call_pernode_memory() */
efi_memmap_walk(filter_rsvd_memory, build_node_maps);
efi_memmap_walk(filter_rsvd_memory, find_pernode_space);
/*
* Initialize the boot memory maps in reverse order since that's
* what the bootmem allocator expects
*/
for (node = MAX_NUMNODES - 1; node >= 0; node--) {
unsigned long pernode, pernodesize, map;
struct bootmem_data *bdp;
if (!node_online(node))
continue;
bdp = &mem_data[node].bootmem_data;
pernode = mem_data[node].pernode_addr;
pernodesize = mem_data[node].pernode_size;
map = pernode + pernodesize;
/* Sanity check... */
if (!pernode)
panic("pernode space for node %d "
"could not be allocated!", node);
init_bootmem_node(mem_data[node].pgdat,
map>>PAGE_SHIFT,
bdp->node_boot_start>>PAGE_SHIFT,
bdp->node_low_pfn);
}
efi_memmap_walk(filter_rsvd_memory, free_node_bootmem);
reserve_pernode_space();
initialize_pernode_data();
max_pfn = max_low_pfn;
find_initrd();
}
/**
* per_cpu_init - setup per-cpu variables
*
* find_pernode_space() does most of this already, we just need to set
* local_per_cpu_offset
*/
void *per_cpu_init(void)
{
int cpu;
if (smp_processor_id() == 0) {
for (cpu = 0; cpu < NR_CPUS; cpu++) {
per_cpu(local_per_cpu_offset, cpu) =
__per_cpu_offset[cpu];
}
}
return __per_cpu_start + __per_cpu_offset[smp_processor_id()];
}
/**
* show_mem - give short summary of memory stats
*
* Shows a simple page count of reserved and used pages in the system.
* For discontig machines, it does this on a per-pgdat basis.
*/
void show_mem(void)
{
int i, total_reserved = 0;
int total_shared = 0, total_cached = 0;
unsigned long total_present = 0;
pg_data_t *pgdat;
printk("Mem-info:\n");
show_free_areas();
printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
for_each_pgdat(pgdat) {
unsigned long present = pgdat->node_present_pages;
int shared = 0, cached = 0, reserved = 0;
printk("Node ID: %d\n", pgdat->node_id);
for(i = 0; i < pgdat->node_spanned_pages; i++) {
if (!ia64_pfn_valid(pgdat->node_start_pfn+i))
continue;
if (PageReserved(pgdat->node_mem_map+i))
reserved++;
else if (PageSwapCache(pgdat->node_mem_map+i))
cached++;
else if (page_count(pgdat->node_mem_map+i))
shared += page_count(pgdat->node_mem_map+i)-1;
}
total_present += present;
total_reserved += reserved;
total_cached += cached;
total_shared += shared;
printk("\t%ld pages of RAM\n", present);
printk("\t%d reserved pages\n", reserved);
printk("\t%d pages shared\n", shared);
printk("\t%d pages swap cached\n", cached);
}
printk("%ld pages of RAM\n", total_present);
printk("%d reserved pages\n", total_reserved);
printk("%d pages shared\n", total_shared);
printk("%d pages swap cached\n", total_cached);
printk("Total of %ld pages in page table cache\n",
pgtable_quicklist_total_size());
printk("%d free buffer pages\n", nr_free_buffer_pages());
}
/**
* call_pernode_memory - use SRAT to call callback functions with node info
* @start: physical start of range
* @len: length of range
* @arg: function to call for each range
*
* efi_memmap_walk() knows nothing about layout of memory across nodes. Find
* out to which node a block of memory belongs. Ignore memory that we cannot
* identify, and split blocks that run across multiple nodes.
*
* Take this opportunity to round the start address up and the end address
* down to page boundaries.
*/
void call_pernode_memory(unsigned long start, unsigned long len, void *arg)
{
unsigned long rs, re, end = start + len;
void (*func)(unsigned long, unsigned long, int);
int i;
start = PAGE_ALIGN(start);
end &= PAGE_MASK;
if (start >= end)
return;
func = arg;
if (!num_node_memblks) {
/* No SRAT table, so assume one node (node 0) */
if (start < end)
(*func)(start, end - start, 0);
return;
}
for (i = 0; i < num_node_memblks; i++) {
rs = max(start, node_memblk[i].start_paddr);
re = min(end, node_memblk[i].start_paddr +
node_memblk[i].size);
if (rs < re)
(*func)(rs, re - rs, node_memblk[i].nid);
if (re == end)
break;
}
}
/**
* count_node_pages - callback to build per-node memory info structures
* @start: physical start of range
* @len: length of range
* @node: node where this range resides
*
* Each node has it's own number of physical pages, DMAable pages, start, and
* end page frame number. This routine will be called by call_pernode_memory()
* for each piece of usable memory and will setup these values for each node.
* Very similar to build_maps().
*/
static __init int count_node_pages(unsigned long start, unsigned long len, int node)
{
unsigned long end = start + len;
mem_data[node].num_physpages += len >> PAGE_SHIFT;
if (start <= __pa(MAX_DMA_ADDRESS))
mem_data[node].num_dma_physpages +=
(min(end, __pa(MAX_DMA_ADDRESS)) - start) >>PAGE_SHIFT;
start = GRANULEROUNDDOWN(start);
start = ORDERROUNDDOWN(start);
end = GRANULEROUNDUP(end);
mem_data[node].max_pfn = max(mem_data[node].max_pfn,
end >> PAGE_SHIFT);
mem_data[node].min_pfn = min(mem_data[node].min_pfn,
start >> PAGE_SHIFT);
return 0;
}
/**
* paging_init - setup page tables
*
* paging_init() sets up the page tables for each node of the system and frees
* the bootmem allocator memory for general use.
*/
void __init paging_init(void)
{
unsigned long max_dma;
unsigned long zones_size[MAX_NR_ZONES];
unsigned long zholes_size[MAX_NR_ZONES];
unsigned long pfn_offset = 0;
int node;
max_dma = virt_to_phys((void *) MAX_DMA_ADDRESS) >> PAGE_SHIFT;
/* so min() will work in count_node_pages */
for_each_online_node(node)
mem_data[node].min_pfn = ~0UL;
efi_memmap_walk(filter_rsvd_memory, count_node_pages);
for_each_online_node(node) {
memset(zones_size, 0, sizeof(zones_size));
memset(zholes_size, 0, sizeof(zholes_size));
num_physpages += mem_data[node].num_physpages;
if (mem_data[node].min_pfn >= max_dma) {
/* All of this node's memory is above ZONE_DMA */
zones_size[ZONE_NORMAL] = mem_data[node].max_pfn -
mem_data[node].min_pfn;
zholes_size[ZONE_NORMAL] = mem_data[node].max_pfn -
mem_data[node].min_pfn -
mem_data[node].num_physpages;
} else if (mem_data[node].max_pfn < max_dma) {
/* All of this node's memory is in ZONE_DMA */
zones_size[ZONE_DMA] = mem_data[node].max_pfn -
mem_data[node].min_pfn;
zholes_size[ZONE_DMA] = mem_data[node].max_pfn -
mem_data[node].min_pfn -
mem_data[node].num_dma_physpages;
} else {
/* This node has memory in both zones */
zones_size[ZONE_DMA] = max_dma -
mem_data[node].min_pfn;
zholes_size[ZONE_DMA] = zones_size[ZONE_DMA] -
mem_data[node].num_dma_physpages;
zones_size[ZONE_NORMAL] = mem_data[node].max_pfn -
max_dma;
zholes_size[ZONE_NORMAL] = zones_size[ZONE_NORMAL] -
(mem_data[node].num_physpages -
mem_data[node].num_dma_physpages);
}
if (node == 0) {
vmalloc_end -=
PAGE_ALIGN(max_low_pfn * sizeof(struct page));
vmem_map = (struct page *) vmalloc_end;
efi_memmap_walk(create_mem_map_page_table, NULL);
printk("Virtual mem_map starts at 0x%p\n", vmem_map);
}
pfn_offset = mem_data[node].min_pfn;
NODE_DATA(node)->node_mem_map = vmem_map + pfn_offset;
free_area_init_node(node, NODE_DATA(node), zones_size,
pfn_offset, zholes_size);
}
zero_page_memmap_ptr = virt_to_page(ia64_imva(empty_zero_page));
}