swh:1:snp:173f8deb0c56c557784b4fd217e7608ac6197844
Tip revision: 62d0cfcb27cf755cebdc93ca95dabc83608007cd authored by Linus Torvalds on 04 February 2007, 18:44:54 UTC
Linux 2.6.20
Linux 2.6.20
Tip revision: 62d0cfc
numa.c
/*
* pSeries NUMA support
*
* Copyright (C) 2002 Anton Blanchard <anton@au.ibm.com>, IBM
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/threads.h>
#include <linux/bootmem.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/mmzone.h>
#include <linux/module.h>
#include <linux/nodemask.h>
#include <linux/cpu.h>
#include <linux/notifier.h>
#include <asm/sparsemem.h>
#include <asm/lmb.h>
#include <asm/system.h>
#include <asm/smp.h>
static int numa_enabled = 1;
static int numa_debug;
#define dbg(args...) if (numa_debug) { printk(KERN_INFO args); }
int numa_cpu_lookup_table[NR_CPUS];
cpumask_t numa_cpumask_lookup_table[MAX_NUMNODES];
struct pglist_data *node_data[MAX_NUMNODES];
EXPORT_SYMBOL(numa_cpu_lookup_table);
EXPORT_SYMBOL(numa_cpumask_lookup_table);
EXPORT_SYMBOL(node_data);
static bootmem_data_t __initdata plat_node_bdata[MAX_NUMNODES];
static int min_common_depth;
static int n_mem_addr_cells, n_mem_size_cells;
static void __cpuinit map_cpu_to_node(int cpu, int node)
{
numa_cpu_lookup_table[cpu] = node;
dbg("adding cpu %d to node %d\n", cpu, node);
if (!(cpu_isset(cpu, numa_cpumask_lookup_table[node])))
cpu_set(cpu, numa_cpumask_lookup_table[node]);
}
#ifdef CONFIG_HOTPLUG_CPU
static void unmap_cpu_from_node(unsigned long cpu)
{
int node = numa_cpu_lookup_table[cpu];
dbg("removing cpu %lu from node %d\n", cpu, node);
if (cpu_isset(cpu, numa_cpumask_lookup_table[node])) {
cpu_clear(cpu, numa_cpumask_lookup_table[node]);
} else {
printk(KERN_ERR "WARNING: cpu %lu not found in node %d\n",
cpu, node);
}
}
#endif /* CONFIG_HOTPLUG_CPU */
static struct device_node * __cpuinit find_cpu_node(unsigned int cpu)
{
unsigned int hw_cpuid = get_hard_smp_processor_id(cpu);
struct device_node *cpu_node = NULL;
const unsigned int *interrupt_server, *reg;
int len;
while ((cpu_node = of_find_node_by_type(cpu_node, "cpu")) != NULL) {
/* Try interrupt server first */
interrupt_server = get_property(cpu_node,
"ibm,ppc-interrupt-server#s", &len);
len = len / sizeof(u32);
if (interrupt_server && (len > 0)) {
while (len--) {
if (interrupt_server[len] == hw_cpuid)
return cpu_node;
}
} else {
reg = get_property(cpu_node, "reg", &len);
if (reg && (len > 0) && (reg[0] == hw_cpuid))
return cpu_node;
}
}
return NULL;
}
/* must hold reference to node during call */
static const int *of_get_associativity(struct device_node *dev)
{
return get_property(dev, "ibm,associativity", NULL);
}
/* Returns nid in the range [0..MAX_NUMNODES-1], or -1 if no useful numa
* info is found.
*/
static int of_node_to_nid_single(struct device_node *device)
{
int nid = -1;
const unsigned int *tmp;
if (min_common_depth == -1)
goto out;
tmp = of_get_associativity(device);
if (!tmp)
goto out;
if (tmp[0] >= min_common_depth)
nid = tmp[min_common_depth];
/* POWER4 LPAR uses 0xffff as invalid node */
if (nid == 0xffff || nid >= MAX_NUMNODES)
nid = -1;
out:
return nid;
}
/* Walk the device tree upwards, looking for an associativity id */
int of_node_to_nid(struct device_node *device)
{
struct device_node *tmp;
int nid = -1;
of_node_get(device);
while (device) {
nid = of_node_to_nid_single(device);
if (nid != -1)
break;
tmp = device;
device = of_get_parent(tmp);
of_node_put(tmp);
}
of_node_put(device);
return nid;
}
EXPORT_SYMBOL_GPL(of_node_to_nid);
/*
* In theory, the "ibm,associativity" property may contain multiple
* associativity lists because a resource may be multiply connected
* into the machine. This resource then has different associativity
* characteristics relative to its multiple connections. We ignore
* this for now. We also assume that all cpu and memory sets have
* their distances represented at a common level. This won't be
* true for heirarchical NUMA.
*
* In any case the ibm,associativity-reference-points should give
* the correct depth for a normal NUMA system.
*
* - Dave Hansen <haveblue@us.ibm.com>
*/
static int __init find_min_common_depth(void)
{
int depth;
const unsigned int *ref_points;
struct device_node *rtas_root;
unsigned int len;
rtas_root = of_find_node_by_path("/rtas");
if (!rtas_root)
return -1;
/*
* this property is 2 32-bit integers, each representing a level of
* depth in the associativity nodes. The first is for an SMP
* configuration (should be all 0's) and the second is for a normal
* NUMA configuration.
*/
ref_points = get_property(rtas_root,
"ibm,associativity-reference-points", &len);
if ((len >= 1) && ref_points) {
depth = ref_points[1];
} else {
dbg("NUMA: ibm,associativity-reference-points not found.\n");
depth = -1;
}
of_node_put(rtas_root);
return depth;
}
static void __init get_n_mem_cells(int *n_addr_cells, int *n_size_cells)
{
struct device_node *memory = NULL;
memory = of_find_node_by_type(memory, "memory");
if (!memory)
panic("numa.c: No memory nodes found!");
*n_addr_cells = prom_n_addr_cells(memory);
*n_size_cells = prom_n_size_cells(memory);
of_node_put(memory);
}
static unsigned long __devinit read_n_cells(int n, const unsigned int **buf)
{
unsigned long result = 0;
while (n--) {
result = (result << 32) | **buf;
(*buf)++;
}
return result;
}
/*
* Figure out to which domain a cpu belongs and stick it there.
* Return the id of the domain used.
*/
static int __cpuinit numa_setup_cpu(unsigned long lcpu)
{
int nid = 0;
struct device_node *cpu = find_cpu_node(lcpu);
if (!cpu) {
WARN_ON(1);
goto out;
}
nid = of_node_to_nid_single(cpu);
if (nid < 0 || !node_online(nid))
nid = any_online_node(NODE_MASK_ALL);
out:
map_cpu_to_node(lcpu, nid);
of_node_put(cpu);
return nid;
}
static int __cpuinit cpu_numa_callback(struct notifier_block *nfb,
unsigned long action,
void *hcpu)
{
unsigned long lcpu = (unsigned long)hcpu;
int ret = NOTIFY_DONE;
switch (action) {
case CPU_UP_PREPARE:
numa_setup_cpu(lcpu);
ret = NOTIFY_OK;
break;
#ifdef CONFIG_HOTPLUG_CPU
case CPU_DEAD:
case CPU_UP_CANCELED:
unmap_cpu_from_node(lcpu);
break;
ret = NOTIFY_OK;
#endif
}
return ret;
}
/*
* Check and possibly modify a memory region to enforce the memory limit.
*
* Returns the size the region should have to enforce the memory limit.
* This will either be the original value of size, a truncated value,
* or zero. If the returned value of size is 0 the region should be
* discarded as it lies wholy above the memory limit.
*/
static unsigned long __init numa_enforce_memory_limit(unsigned long start,
unsigned long size)
{
/*
* We use lmb_end_of_DRAM() in here instead of memory_limit because
* we've already adjusted it for the limit and it takes care of
* having memory holes below the limit.
*/
if (! memory_limit)
return size;
if (start + size <= lmb_end_of_DRAM())
return size;
if (start >= lmb_end_of_DRAM())
return 0;
return lmb_end_of_DRAM() - start;
}
/*
* Extract NUMA information from the ibm,dynamic-reconfiguration-memory
* node. This assumes n_mem_{addr,size}_cells have been set.
*/
static void __init parse_drconf_memory(struct device_node *memory)
{
const unsigned int *lm, *dm, *aa;
unsigned int ls, ld, la;
unsigned int n, aam, aalen;
unsigned long lmb_size, size;
int nid, default_nid = 0;
unsigned int start, ai, flags;
lm = get_property(memory, "ibm,lmb-size", &ls);
dm = get_property(memory, "ibm,dynamic-memory", &ld);
aa = get_property(memory, "ibm,associativity-lookup-arrays", &la);
if (!lm || !dm || !aa ||
ls < sizeof(unsigned int) || ld < sizeof(unsigned int) ||
la < 2 * sizeof(unsigned int))
return;
lmb_size = read_n_cells(n_mem_size_cells, &lm);
n = *dm++; /* number of LMBs */
aam = *aa++; /* number of associativity lists */
aalen = *aa++; /* length of each associativity list */
if (ld < (n * (n_mem_addr_cells + 4) + 1) * sizeof(unsigned int) ||
la < (aam * aalen + 2) * sizeof(unsigned int))
return;
for (; n != 0; --n) {
start = read_n_cells(n_mem_addr_cells, &dm);
ai = dm[2];
flags = dm[3];
dm += 4;
/* 0x80 == reserved, 0x8 = assigned to us */
if ((flags & 0x80) || !(flags & 0x8))
continue;
nid = default_nid;
/* flags & 0x40 means associativity index is invalid */
if (min_common_depth > 0 && min_common_depth <= aalen &&
(flags & 0x40) == 0 && ai < aam) {
/* this is like of_node_to_nid_single */
nid = aa[ai * aalen + min_common_depth - 1];
if (nid == 0xffff || nid >= MAX_NUMNODES)
nid = default_nid;
}
node_set_online(nid);
size = numa_enforce_memory_limit(start, lmb_size);
if (!size)
continue;
add_active_range(nid, start >> PAGE_SHIFT,
(start >> PAGE_SHIFT) + (size >> PAGE_SHIFT));
}
}
static int __init parse_numa_properties(void)
{
struct device_node *cpu = NULL;
struct device_node *memory = NULL;
int default_nid = 0;
unsigned long i;
if (numa_enabled == 0) {
printk(KERN_WARNING "NUMA disabled by user\n");
return -1;
}
min_common_depth = find_min_common_depth();
if (min_common_depth < 0)
return min_common_depth;
dbg("NUMA associativity depth for CPU/Memory: %d\n", min_common_depth);
/*
* Even though we connect cpus to numa domains later in SMP
* init, we need to know the node ids now. This is because
* each node to be onlined must have NODE_DATA etc backing it.
*/
for_each_present_cpu(i) {
int nid;
cpu = find_cpu_node(i);
BUG_ON(!cpu);
nid = of_node_to_nid_single(cpu);
of_node_put(cpu);
/*
* Don't fall back to default_nid yet -- we will plug
* cpus into nodes once the memory scan has discovered
* the topology.
*/
if (nid < 0)
continue;
node_set_online(nid);
}
get_n_mem_cells(&n_mem_addr_cells, &n_mem_size_cells);
memory = NULL;
while ((memory = of_find_node_by_type(memory, "memory")) != NULL) {
unsigned long start;
unsigned long size;
int nid;
int ranges;
const unsigned int *memcell_buf;
unsigned int len;
memcell_buf = get_property(memory,
"linux,usable-memory", &len);
if (!memcell_buf || len <= 0)
memcell_buf = get_property(memory, "reg", &len);
if (!memcell_buf || len <= 0)
continue;
/* ranges in cell */
ranges = (len >> 2) / (n_mem_addr_cells + n_mem_size_cells);
new_range:
/* these are order-sensitive, and modify the buffer pointer */
start = read_n_cells(n_mem_addr_cells, &memcell_buf);
size = read_n_cells(n_mem_size_cells, &memcell_buf);
/*
* Assumption: either all memory nodes or none will
* have associativity properties. If none, then
* everything goes to default_nid.
*/
nid = of_node_to_nid_single(memory);
if (nid < 0)
nid = default_nid;
node_set_online(nid);
if (!(size = numa_enforce_memory_limit(start, size))) {
if (--ranges)
goto new_range;
else
continue;
}
add_active_range(nid, start >> PAGE_SHIFT,
(start >> PAGE_SHIFT) + (size >> PAGE_SHIFT));
if (--ranges)
goto new_range;
}
/*
* Now do the same thing for each LMB listed in the ibm,dynamic-memory
* property in the ibm,dynamic-reconfiguration-memory node.
*/
memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
if (memory)
parse_drconf_memory(memory);
return 0;
}
static void __init setup_nonnuma(void)
{
unsigned long top_of_ram = lmb_end_of_DRAM();
unsigned long total_ram = lmb_phys_mem_size();
unsigned long start_pfn, end_pfn;
unsigned int i;
printk(KERN_DEBUG "Top of RAM: 0x%lx, Total RAM: 0x%lx\n",
top_of_ram, total_ram);
printk(KERN_DEBUG "Memory hole size: %ldMB\n",
(top_of_ram - total_ram) >> 20);
for (i = 0; i < lmb.memory.cnt; ++i) {
start_pfn = lmb.memory.region[i].base >> PAGE_SHIFT;
end_pfn = start_pfn + lmb_size_pages(&lmb.memory, i);
add_active_range(0, start_pfn, end_pfn);
}
node_set_online(0);
}
void __init dump_numa_cpu_topology(void)
{
unsigned int node;
unsigned int cpu, count;
if (min_common_depth == -1 || !numa_enabled)
return;
for_each_online_node(node) {
printk(KERN_DEBUG "Node %d CPUs:", node);
count = 0;
/*
* If we used a CPU iterator here we would miss printing
* the holes in the cpumap.
*/
for (cpu = 0; cpu < NR_CPUS; cpu++) {
if (cpu_isset(cpu, numa_cpumask_lookup_table[node])) {
if (count == 0)
printk(" %u", cpu);
++count;
} else {
if (count > 1)
printk("-%u", cpu - 1);
count = 0;
}
}
if (count > 1)
printk("-%u", NR_CPUS - 1);
printk("\n");
}
}
static void __init dump_numa_memory_topology(void)
{
unsigned int node;
unsigned int count;
if (min_common_depth == -1 || !numa_enabled)
return;
for_each_online_node(node) {
unsigned long i;
printk(KERN_DEBUG "Node %d Memory:", node);
count = 0;
for (i = 0; i < lmb_end_of_DRAM();
i += (1 << SECTION_SIZE_BITS)) {
if (early_pfn_to_nid(i >> PAGE_SHIFT) == node) {
if (count == 0)
printk(" 0x%lx", i);
++count;
} else {
if (count > 0)
printk("-0x%lx", i);
count = 0;
}
}
if (count > 0)
printk("-0x%lx", i);
printk("\n");
}
}
/*
* Allocate some memory, satisfying the lmb or bootmem allocator where
* required. nid is the preferred node and end is the physical address of
* the highest address in the node.
*
* Returns the physical address of the memory.
*/
static void __init *careful_allocation(int nid, unsigned long size,
unsigned long align,
unsigned long end_pfn)
{
int new_nid;
unsigned long ret = __lmb_alloc_base(size, align, end_pfn << PAGE_SHIFT);
/* retry over all memory */
if (!ret)
ret = __lmb_alloc_base(size, align, lmb_end_of_DRAM());
if (!ret)
panic("numa.c: cannot allocate %lu bytes on node %d",
size, nid);
/*
* If the memory came from a previously allocated node, we must
* retry with the bootmem allocator.
*/
new_nid = early_pfn_to_nid(ret >> PAGE_SHIFT);
if (new_nid < nid) {
ret = (unsigned long)__alloc_bootmem_node(NODE_DATA(new_nid),
size, align, 0);
if (!ret)
panic("numa.c: cannot allocate %lu bytes on node %d",
size, new_nid);
ret = __pa(ret);
dbg("alloc_bootmem %lx %lx\n", ret, size);
}
return (void *)ret;
}
static struct notifier_block __cpuinitdata ppc64_numa_nb = {
.notifier_call = cpu_numa_callback,
.priority = 1 /* Must run before sched domains notifier. */
};
void __init do_init_bootmem(void)
{
int nid;
unsigned int i;
min_low_pfn = 0;
max_low_pfn = lmb_end_of_DRAM() >> PAGE_SHIFT;
max_pfn = max_low_pfn;
if (parse_numa_properties())
setup_nonnuma();
else
dump_numa_memory_topology();
register_cpu_notifier(&ppc64_numa_nb);
cpu_numa_callback(&ppc64_numa_nb, CPU_UP_PREPARE,
(void *)(unsigned long)boot_cpuid);
for_each_online_node(nid) {
unsigned long start_pfn, end_pfn;
unsigned long bootmem_paddr;
unsigned long bootmap_pages;
get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
/* Allocate the node structure node local if possible */
NODE_DATA(nid) = careful_allocation(nid,
sizeof(struct pglist_data),
SMP_CACHE_BYTES, end_pfn);
NODE_DATA(nid) = __va(NODE_DATA(nid));
memset(NODE_DATA(nid), 0, sizeof(struct pglist_data));
dbg("node %d\n", nid);
dbg("NODE_DATA() = %p\n", NODE_DATA(nid));
NODE_DATA(nid)->bdata = &plat_node_bdata[nid];
NODE_DATA(nid)->node_start_pfn = start_pfn;
NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
if (NODE_DATA(nid)->node_spanned_pages == 0)
continue;
dbg("start_paddr = %lx\n", start_pfn << PAGE_SHIFT);
dbg("end_paddr = %lx\n", end_pfn << PAGE_SHIFT);
bootmap_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
bootmem_paddr = (unsigned long)careful_allocation(nid,
bootmap_pages << PAGE_SHIFT,
PAGE_SIZE, end_pfn);
memset(__va(bootmem_paddr), 0, bootmap_pages << PAGE_SHIFT);
dbg("bootmap_paddr = %lx\n", bootmem_paddr);
init_bootmem_node(NODE_DATA(nid), bootmem_paddr >> PAGE_SHIFT,
start_pfn, end_pfn);
free_bootmem_with_active_regions(nid, end_pfn);
/* Mark reserved regions on this node */
for (i = 0; i < lmb.reserved.cnt; i++) {
unsigned long physbase = lmb.reserved.region[i].base;
unsigned long size = lmb.reserved.region[i].size;
unsigned long start_paddr = start_pfn << PAGE_SHIFT;
unsigned long end_paddr = end_pfn << PAGE_SHIFT;
if (early_pfn_to_nid(physbase >> PAGE_SHIFT) != nid &&
early_pfn_to_nid((physbase+size-1) >> PAGE_SHIFT) != nid)
continue;
if (physbase < end_paddr &&
(physbase+size) > start_paddr) {
/* overlaps */
if (physbase < start_paddr) {
size -= start_paddr - physbase;
physbase = start_paddr;
}
if (size > end_paddr - physbase)
size = end_paddr - physbase;
dbg("reserve_bootmem %lx %lx\n", physbase,
size);
reserve_bootmem_node(NODE_DATA(nid), physbase,
size);
}
}
sparse_memory_present_with_active_regions(nid);
}
}
void __init paging_init(void)
{
unsigned long max_zone_pfns[MAX_NR_ZONES];
memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
max_zone_pfns[ZONE_DMA] = lmb_end_of_DRAM() >> PAGE_SHIFT;
free_area_init_nodes(max_zone_pfns);
}
static int __init early_numa(char *p)
{
if (!p)
return 0;
if (strstr(p, "off"))
numa_enabled = 0;
if (strstr(p, "debug"))
numa_debug = 1;
return 0;
}
early_param("numa", early_numa);
#ifdef CONFIG_MEMORY_HOTPLUG
/*
* Find the node associated with a hot added memory section. Section
* corresponds to a SPARSEMEM section, not an LMB. It is assumed that
* sections are fully contained within a single LMB.
*/
int hot_add_scn_to_nid(unsigned long scn_addr)
{
struct device_node *memory = NULL;
nodemask_t nodes;
int default_nid = any_online_node(NODE_MASK_ALL);
int nid;
if (!numa_enabled || (min_common_depth < 0))
return default_nid;
while ((memory = of_find_node_by_type(memory, "memory")) != NULL) {
unsigned long start, size;
int ranges;
const unsigned int *memcell_buf;
unsigned int len;
memcell_buf = get_property(memory, "reg", &len);
if (!memcell_buf || len <= 0)
continue;
/* ranges in cell */
ranges = (len >> 2) / (n_mem_addr_cells + n_mem_size_cells);
ha_new_range:
start = read_n_cells(n_mem_addr_cells, &memcell_buf);
size = read_n_cells(n_mem_size_cells, &memcell_buf);
nid = of_node_to_nid_single(memory);
/* Domains not present at boot default to 0 */
if (nid < 0 || !node_online(nid))
nid = default_nid;
if ((scn_addr >= start) && (scn_addr < (start + size))) {
of_node_put(memory);
goto got_nid;
}
if (--ranges) /* process all ranges in cell */
goto ha_new_range;
}
BUG(); /* section address should be found above */
return 0;
/* Temporary code to ensure that returned node is not empty */
got_nid:
nodes_setall(nodes);
while (NODE_DATA(nid)->node_spanned_pages == 0) {
node_clear(nid, nodes);
nid = any_online_node(nodes);
}
return nid;
}
#endif /* CONFIG_MEMORY_HOTPLUG */