OpenCloudOS-Kernel/arch/ia64/mm/discontig.c

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/*
* 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;
static nodemask_t memory_less_mask __initdata;
/*
* To prevent cache aliasing effects, align per-node structures so that they
* start at addresses that are strided by node number.
*/
#define MAX_NODE_ALIGN_OFFSET (32 * 1024 * 1024)
#define NODEDATA_ALIGN(addr, node) \
((((addr) + 1024*1024-1) & ~(1024*1024-1)) + \
(((node)*PERCPU_PAGE_SIZE) & (MAX_NODE_ALIGN_OFFSET - 1)))
/**
* 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_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 __init 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;
}
/**
* compute_pernodesize - compute size of pernode data
* @node: the node id.
*/
static unsigned long __init compute_pernodesize(int node)
{
unsigned long pernodesize = 0, cpus;
cpus = early_nr_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);
return pernodesize;
}
/**
* per_cpu_node_setup - setup per-cpu areas on each node
* @cpu_data: per-cpu area on this node
* @node: node to setup
*
* 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. Return a pointer to
* the end of the area.
*/
static void *per_cpu_node_setup(void *cpu_data, int node)
{
#ifdef CONFIG_SMP
int cpu;
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;
}
}
#endif
return cpu_data;
}
/**
* fill_pernode - initialize pernode data.
* @node: the node id.
* @pernode: physical address of pernode data
* @pernodesize: size of the pernode data
*/
static void __init fill_pernode(int node, unsigned long pernode,
unsigned long pernodesize)
{
void *cpu_data;
int cpus = early_nr_cpus_node(node);
struct bootmem_data *bdp = &mem_data[node].bootmem_data;
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));
cpu_data = per_cpu_node_setup(cpu_data, node);
return;
}
/**
* 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;
unsigned long pernodesize = 0, pernode, pages, mapsize;
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.
*/
pernodesize = compute_pernodesize(node);
pernode = NODEDATA_ALIGN(start, node);
/* Is this range big enough for what we want to store here? */
if (start + len > (pernode + pernodesize + mapsize))
fill_pernode(node, pernode, pernodesize);
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;
if (node_isset(node, memory_less_mask))
continue;
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)
{
pg_data_t *pgdat_list[MAX_NUMNODES];
int cpu, node;
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));
}
#ifdef CONFIG_SMP
/* 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;
}
#else
{
struct cpuinfo_ia64 *cpu0_cpu_info;
cpu = 0;
node = node_cpuid[cpu].nid;
cpu0_cpu_info = (struct cpuinfo_ia64 *)(__phys_per_cpu_start +
((char *)&per_cpu__cpu_info - __per_cpu_start));
cpu0_cpu_info->node_data = mem_data[node].node_data;
}
#endif /* CONFIG_SMP */
}
/**
* memory_less_node_alloc - * attempt to allocate memory on the best NUMA slit
* node but fall back to any other node when __alloc_bootmem_node fails
* for best.
* @nid: node id
* @pernodesize: size of this node's pernode data
*/
static void __init *memory_less_node_alloc(int nid, unsigned long pernodesize)
{
void *ptr = NULL;
u8 best = 0xff;
int bestnode = -1, node, anynode = 0;
for_each_online_node(node) {
if (node_isset(node, memory_less_mask))
continue;
else if (node_distance(nid, node) < best) {
best = node_distance(nid, node);
bestnode = node;
}
anynode = node;
}
if (bestnode == -1)
bestnode = anynode;
ptr = __alloc_bootmem_node(mem_data[bestnode].pgdat, pernodesize,
PERCPU_PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
return ptr;
}
/**
* pgdat_insert - insert the pgdat into global pgdat_list
* @pgdat: the pgdat for a node.
*/
static void __init pgdat_insert(pg_data_t *pgdat)
{
pg_data_t *prev = NULL, *next;
for_each_pgdat(next)
if (pgdat->node_id < next->node_id)
break;
else
prev = next;
if (prev) {
prev->pgdat_next = pgdat;
pgdat->pgdat_next = next;
} else {
pgdat->pgdat_next = pgdat_list;
pgdat_list = pgdat;
}
return;
}
/**
* memory_less_nodes - allocate and initialize CPU only nodes pernode
* information.
*/
static void __init memory_less_nodes(void)
{
unsigned long pernodesize;
void *pernode;
int node;
for_each_node_mask(node, memory_less_mask) {
pernodesize = compute_pernodesize(node);
pernode = memory_less_node_alloc(node, pernodesize);
fill_pernode(node, __pa(pernode), pernodesize);
}
return;
}
#ifdef CONFIG_SPARSEMEM
/**
* register_sparse_mem - notify SPARSEMEM that this memory range exists.
* @start: physical start of range
* @end: physical end of range
* @arg: unused
*
* Simply calls SPARSEMEM to register memory section(s).
*/
static int __init register_sparse_mem(unsigned long start, unsigned long end,
void *arg)
{
int nid;
start = __pa(start) >> PAGE_SHIFT;
end = __pa(end) >> PAGE_SHIFT;
nid = early_pfn_to_nid(start);
memory_present(nid, start, end);
return 0;
}
static void __init arch_sparse_init(void)
{
efi_memmap_walk(register_sparse_mem, NULL);
sparse_init();
}
#else
#define arch_sparse_init() do {} while (0)
#endif
/**
* 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);
}
nodes_or(memory_less_mask, memory_less_mask, node_online_map);
min_low_pfn = -1;
max_low_pfn = 0;
/* 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);
for_each_online_node(node)
if (mem_data[node].bootmem_data.node_low_pfn) {
node_clear(node, memory_less_mask);
mem_data[node].min_pfn = ~0UL;
}
/*
* 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;
else if (node_isset(node, memory_less_mask))
continue;
bdp = &mem_data[node].bootmem_data;
pernode = mem_data[node].pernode_addr;
pernodesize = mem_data[node].pernode_size;
map = pernode + pernodesize;
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();
memory_less_nodes();
initialize_pernode_data();
max_pfn = max_low_pfn;
find_initrd();
}
#ifdef CONFIG_SMP
/**
* 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 __cpuinit *per_cpu_init(void)
{
int cpu;
static int first_time = 1;
if (smp_processor_id() != 0)
return __per_cpu_start + __per_cpu_offset[smp_processor_id()];
if (first_time) {
first_time = 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()];
}
#endif /* CONFIG_SMP */
/**
* 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;
unsigned long flags;
int shared = 0, cached = 0, reserved = 0;
printk("Node ID: %d\n", pgdat->node_id);
pgdat_resize_lock(pgdat, &flags);
present = pgdat->node_present_pages;
for(i = 0; i < pgdat->node_spanned_pages; i++) {
struct page *page;
if (pfn_valid(pgdat->node_start_pfn + i))
page = pfn_to_page(pgdat->node_start_pfn + i);
else
continue;
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if (PageReserved(page))
reserved++;
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else if (PageSwapCache(page))
cached++;
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else if (page_count(page))
shared += page_count(page)-1;
}
pgdat_resize_unlock(pgdat, &flags);
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);
[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>
2005-04-26 04:13:16 +08:00
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;
arch_sparse_init();
efi_memmap_walk(filter_rsvd_memory, count_node_pages);
#ifdef CONFIG_VIRTUAL_MEM_MAP
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);
#endif
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);
}
pfn_offset = mem_data[node].min_pfn;
#ifdef CONFIG_VIRTUAL_MEM_MAP
NODE_DATA(node)->node_mem_map = vmem_map + pfn_offset;
#endif
free_area_init_node(node, NODE_DATA(node), zones_size,
pfn_offset, zholes_size);
}
/*
* Make memory less nodes become a member of the known nodes.
*/
for_each_node_mask(node, memory_less_mask)
pgdat_insert(mem_data[node].pgdat);
zero_page_memmap_ptr = virt_to_page(ia64_imva(empty_zero_page));
}