/*
* 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/export.h>
#include <linux/nodemask.h>
#include <linux/cpu.h>
#include <linux/notifier.h>
#include <linux/memblock.h>
#include <linux/of.h>
#include <linux/pfn.h>
#include <linux/cpuset.h>
#include <linux/node.h>
#include <linux/stop_machine.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/uaccess.h>
#include <linux/slab.h>
#include <asm/cputhreads.h>
#include <asm/sparsemem.h>
#include <asm/prom.h>
#include <asm/smp.h>
#include <asm/cputhreads.h>
#include <asm/topology.h>
#include <asm/firmware.h>
#include <asm/paca.h>
#include <asm/hvcall.h>
#include <asm/setup.h>
#include <asm/vdso.h>
static int numa_enabled = 1;
static char *cmdline __initdata;
static int numa_debug;
#define dbg(args...) if (numa_debug) { printk(KERN_INFO args); }
int numa_cpu_lookup_table[NR_CPUS];
cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
struct pglist_data *node_data[MAX_NUMNODES];
EXPORT_SYMBOL(numa_cpu_lookup_table);
EXPORT_SYMBOL(node_to_cpumask_map);
EXPORT_SYMBOL(node_data);
static int min_common_depth;
static int n_mem_addr_cells, n_mem_size_cells;
static int form1_affinity;
#define MAX_DISTANCE_REF_POINTS 4
static int distance_ref_points_depth;
static const __be32 *distance_ref_points;
static int distance_lookup_table[MAX_NUMNODES][MAX_DISTANCE_REF_POINTS];
/*
* Allocate node_to_cpumask_map based on number of available nodes
* Requires node_possible_map to be valid.
*
* Note: cpumask_of_node() is not valid until after this is done.
*/
static void __init setup_node_to_cpumask_map(void)
{
unsigned int node;
/* setup nr_node_ids if not done yet */
if (nr_node_ids == MAX_NUMNODES)
setup_nr_node_ids();
/* allocate the map */
for (node = 0; node < nr_node_ids; node++)
alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
/* cpumask_of_node() will now work */
dbg("Node to cpumask map for %d nodes\n", nr_node_ids);
}
static int __init fake_numa_create_new_node(unsigned long end_pfn,
unsigned int *nid)
{
unsigned long long mem;
char *p = cmdline;
static unsigned int fake_nid;
static unsigned long long curr_boundary;
/*
* Modify node id, iff we started creating NUMA nodes
* We want to continue from where we left of the last time
*/
if (fake_nid)
*nid = fake_nid;
/*
* In case there are no more arguments to parse, the
* node_id should be the same as the last fake node id
* (we've handled this above).
*/
if (!p)
return 0;
mem = memparse(p, &p);
if (!mem)
return 0;
if (mem < curr_boundary)
return 0;
curr_boundary = mem;
if ((end_pfn << PAGE_SHIFT) > mem) {
/*
* Skip commas and spaces
*/
while (*p == ',' || *p == ' ' || *p == '\t')
p++;
cmdline = p;
fake_nid++;
*nid = fake_nid;
dbg("created new fake_node with id %d\n", fake_nid);
return 1;
}
return 0;
}
/*
* get_node_active_region - Return active region containing pfn
* Active range returned is empty if none found.
* @pfn: The page to return the region for
* @node_ar: Returned set to the active region containing @pfn
*/
static void __init get_node_active_region(unsigned long pfn,
struct node_active_region *node_ar)
{
unsigned long start_pfn, end_pfn;
int i, nid;
for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) {
if (pfn >= start_pfn && pfn < end_pfn) {
node_ar->nid = nid;
node_ar->start_pfn = start_pfn;
node_ar->end_pfn = end_pfn;
break;
}
}
}
static void reset_numa_cpu_lookup_table(void)
{
unsigned int cpu;
for_each_possible_cpu(cpu)
numa_cpu_lookup_table[cpu] = -1;
}
static void update_numa_cpu_lookup_table(unsigned int cpu, int node)
{
numa_cpu_lookup_table[cpu] = node;
}
static void map_cpu_to_node(int cpu, int node)
{
update_numa_cpu_lookup_table(cpu, node);
dbg("adding cpu %d to node %d\n", cpu, node);
if (!(cpumask_test_cpu(cpu, node_to_cpumask_map[node])))
cpumask_set_cpu(cpu, node_to_cpumask_map[node]);
}
#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PPC_SPLPAR)
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 (cpumask_test_cpu(cpu, node_to_cpumask_map[node])) {
cpumask_clear_cpu(cpu, node_to_cpumask_map[node]);
} else {
printk(KERN_ERR "WARNING: cpu %lu not found in node %d\n",
cpu, node);
}
}
#endif /* CONFIG_HOTPLUG_CPU || CONFIG_PPC_SPLPAR */
/* must hold reference to node during call */
static const __be32 *of_get_associativity(struct device_node *dev)
{
return of_get_property(dev, "ibm,associativity", NULL);
}
/*
* Returns the property linux,drconf-usable-memory if
* it exists (the property exists only in kexec/kdump kernels,
* added by kexec-tools)
*/
static const __be32 *of_get_usable_memory(struct device_node *memory)
{
const __be32 *prop;
u32 len;
prop = of_get_property(memory, "linux,drconf-usable-memory", &len);
if (!prop || len < sizeof(unsigned int))
return NULL;
return prop;
}
int __node_distance(int a, int b)
{
int i;
int distance = LOCAL_DISTANCE;
if (!form1_affinity)
return ((a == b) ? LOCAL_DISTANCE : REMOTE_DISTANCE);
for (i = 0; i < distance_ref_points_depth; i++) {
if (distance_lookup_table[a][i] == distance_lookup_table[b][i])
break;
/* Double the distance for each NUMA level */
distance *= 2;
}
return distance;
}
static void initialize_distance_lookup_table(int nid,
const __be32 *associativity)
{
int i;
if (!form1_affinity)
return;
for (i = 0; i < distance_ref_points_depth; i++) {
const __be32 *entry;
entry = &associativity[be32_to_cpu(distance_ref_points[i])];
distance_lookup_table[nid][i] = of_read_number(entry, 1);
}
}
/* Returns nid in the range [0..MAX_NUMNODES-1], or -1 if no useful numa
* info is found.
*/
static int associativity_to_nid(const __be32 *associativity)
{
int nid = -1;
if (min_common_depth == -1)
goto out;
if (of_read_number(associativity, 1) >= min_common_depth)
nid = of_read_number(&associativity[min_common_depth], 1);
/* POWER4 LPAR uses 0xffff as invalid node */
if (nid == 0xffff || nid >= MAX_NUMNODES)
nid = -1;
if (nid > 0 &&
of_read_number(associativity, 1) >= distance_ref_points_depth)
initialize_distance_lookup_table(nid, associativity);
out:
return nid;
}
/* Returns the nid associated with the given device tree node,
* or -1 if not found.
*/
static int of_node_to_nid_single(struct device_node *device)
{
int nid = -1;
const __be32 *tmp;
tmp = of_get_associativity(device);
if (tmp)
nid = associativity_to_nid(tmp);
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);
static int __init find_min_common_depth(void)
{
int depth;
struct device_node *root;
if (firmware_has_feature(FW_FEATURE_OPAL))
root = of_find_node_by_path("/ibm,opal");
else
root = of_find_node_by_path("/rtas");
if (!root)
root = of_find_node_by_path("/");
/*
* This property is a set of 32-bit integers, each representing
* an index into the ibm,associativity nodes.
*
* With form 0 affinity the first integer is for an SMP configuration
* (should be all 0's) and the second is for a normal NUMA
* configuration. We have only one level of NUMA.
*
* With form 1 affinity the first integer is the most significant
* NUMA boundary and the following are progressively less significant
* boundaries. There can be more than one level of NUMA.
*/
distance_ref_points = of_get_property(root,
"ibm,associativity-reference-points",
&distance_ref_points_depth);
if (!distance_ref_points) {
dbg("NUMA: ibm,associativity-reference-points not found.\n");
goto err;
}
distance_ref_points_depth /= sizeof(int);
if (firmware_has_feature(FW_FEATURE_OPAL) ||
firmware_has_feature(FW_FEATURE_TYPE1_AFFINITY)) {
dbg("Using form 1 affinity\n");
form1_affinity = 1;
}
if (form1_affinity) {
depth = of_read_number(distance_ref_points, 1);
} else {
if (distance_ref_points_depth < 2) {
printk(KERN_WARNING "NUMA: "
"short ibm,associativity-reference-points\n");
goto err;
}
depth = of_read_number(&distance_ref_points[1], 1);
}
/*
* Warn and cap if the hardware supports more than
* MAX_DISTANCE_REF_POINTS domains.
*/
if (distance_ref_points_depth > MAX_DISTANCE_REF_POINTS) {
printk(KERN_WARNING "NUMA: distance array capped at "
"%d entries\n", MAX_DISTANCE_REF_POINTS);
distance_ref_points_depth = MAX_DISTANCE_REF_POINTS;
}
of_node_put(root);
return depth;
err:
of_node_put(root);
return -1;
}
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 = of_n_addr_cells(memory);
*n_size_cells = of_n_size_cells(memory);
of_node_put(memory);
}
static unsigned long read_n_cells(int n, const __be32 **buf)
{
unsigned long result = 0;
while (n--) {
result = (result << 32) | of_read_number(*buf, 1);
(*buf)++;
}
return result;
}
/*
* Read the next memblock list entry from the ibm,dynamic-memory property
* and return the information in the provided of_drconf_cell structure.
*/
static void read_drconf_cell(struct of_drconf_cell *drmem, const __be32 **cellp)
{
const __be32 *cp;
drmem->base_addr = read_n_cells(n_mem_addr_cells, cellp);
cp = *cellp;
drmem->drc_index = of_read_number(cp, 1);
drmem->reserved = of_read_number(&cp[1], 1);
drmem->aa_index = of_read_number(&cp[2], 1);
drmem->flags = of_read_number(&cp[3], 1);
*cellp = cp + 4;
}
/*
* Retrieve and validate the ibm,dynamic-memory property of the device tree.
*
* The layout of the ibm,dynamic-memory property is a number N of memblock
* list entries followed by N memblock list entries. Each memblock list entry
* contains information as laid out in the of_drconf_cell struct above.
*/
static int of_get_drconf_memory(struct device_node *memory, const __be32 **dm)
{
const __be32 *prop;
u32 len, entries;
prop = of_get_property(memory, "ibm,dynamic-memory", &len);
if (!prop || len < sizeof(unsigned int))
return 0;
entries = of_read_number(prop++, 1);
/* Now that we know the number of entries, revalidate the size
* of the property read in to ensure we have everything
*/
if (len < (entries * (n_mem_addr_cells + 4) + 1) * sizeof(unsigned int))
return 0;
*dm = prop;
return entries;
}
/*
* Retrieve and validate the ibm,lmb-size property for drconf memory
* from the device tree.
*/
static u64 of_get_lmb_size(struct device_node *memory)
{
const __be32 *prop;
u32 len;
prop = of_get_property(memory, "ibm,lmb-size", &len);
if (!prop || len < sizeof(unsigned int))
return 0;
return read_n_cells(n_mem_size_cells, &prop);
}
struct assoc_arrays {
u32 n_arrays;
u32 array_sz;
const __be32 *arrays;
};
/*
* Retrieve and validate the list of associativity arrays for drconf
* memory from the ibm,associativity-lookup-arrays property of the
* device tree..
*
* The layout of the ibm,associativity-lookup-arrays property is a number N
* indicating the number of associativity arrays, followed by a number M
* indicating the size of each associativity array, followed by a list
* of N associativity arrays.
*/
static int of_get_assoc_arrays(struct device_node *memory,
struct assoc_arrays *aa)
{
const __be32 *prop;
u32 len;
prop = of_get_property(memory, "ibm,associativity-lookup-arrays", &len);
if (!prop || len < 2 * sizeof(unsigned int))
return -1;
aa->n_arrays = of_read_number(prop++, 1);
aa->array_sz = of_read_number(prop++, 1);
/* Now that we know the number of arrays and size of each array,
* revalidate the size of the property read in.
*/
if (len < (aa->n_arrays * aa->array_sz + 2) * sizeof(unsigned int))
return -1;
aa->arrays = prop;
return 0;
}
/*
* This is like of_node_to_nid_single() for memory represented in the
* ibm,dynamic-reconfiguration-memory node.
*/
static int of_drconf_to_nid_single(struct of_drconf_cell *drmem,
struct assoc_arrays *aa)
{
int default_nid = 0;
int nid = default_nid;
int index;
if (min_common_depth > 0 && min_common_depth <= aa->array_sz &&
!(drmem->flags & DRCONF_MEM_AI_INVALID) &&
drmem->aa_index < aa->n_arrays) {
index = drmem->aa_index * aa->array_sz + min_common_depth - 1;
nid = of_read_number(&aa->arrays[index], 1);
if (nid == 0xffff || nid >= MAX_NUMNODES)
nid = default_nid;
}
return nid;
}
/*
* Figure out to which domain a cpu belongs and stick it there.
* Return the id of the domain used.
*/
static int numa_setup_cpu(unsigned long lcpu)
{
int nid;
struct device_node *cpu;
/*
* If a valid cpu-to-node mapping is already available, use it
* directly instead of querying the firmware, since it represents
* the most recent mapping notified to us by the platform (eg: VPHN).
*/
if ((nid = numa_cpu_lookup_table[lcpu]) >= 0) {
map_cpu_to_node(lcpu, nid);
return nid;
}
cpu = of_get_cpu_node(lcpu, NULL);
if (!cpu) {
WARN_ON(1);
nid = 0;
goto out;
}
nid = of_node_to_nid_single(cpu);
if (nid < 0 || !node_online(nid))
nid = first_online_node;
out:
map_cpu_to_node(lcpu, nid);
of_node_put(cpu);
return nid;
}
static void verify_cpu_node_mapping(int cpu, int node)
{
int base, sibling, i;
/* Verify that all the threads in the core belong to the same node */
base = cpu_first_thread_sibling(cpu);
for (i = 0; i < threads_per_core; i++) {
sibling = base + i;
if (sibling == cpu || cpu_is_offline(sibling))
continue;
if (cpu_to_node(sibling) != node) {
WARN(1, "CPU thread siblings %d and %d don't belong"
" to the same node!\n", cpu, sibling);
break;
}
}
}
static int cpu_numa_callback(struct notifier_block *nfb, unsigned long action,
void *hcpu)
{
unsigned long lcpu = (unsigned long)hcpu;
int ret = NOTIFY_DONE, nid;
switch (action) {
case CPU_UP_PREPARE:
case CPU_UP_PREPARE_FROZEN:
nid = numa_setup_cpu(lcpu);
verify_cpu_node_mapping((int)lcpu, nid);
ret = NOTIFY_OK;
break;
#ifdef CONFIG_HOTPLUG_CPU
case CPU_DEAD:
case CPU_DEAD_FROZEN:
case CPU_UP_CANCELED:
case CPU_UP_CANCELED_FROZEN:
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 wholly above the memory limit.
*/
static unsigned long __init numa_enforce_memory_limit(unsigned long start,
unsigned long size)
{
/*
* We use memblock_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. Also, in the case of
* iommu_is_off, memory_limit is not set but is implicitly enforced.
*/
if (start + size <= memblock_end_of_DRAM())
return size;
if (start >= memblock_end_of_DRAM())
return 0;
return memblock_end_of_DRAM() - start;
}
/*
* Reads the counter for a given entry in
* linux,drconf-usable-memory property
*/
static inline int __init read_usm_ranges(const __be32 **usm)
{
/*
* For each lmb in ibm,dynamic-memory a corresponding
* entry in linux,drconf-usable-memory property contains
* a counter followed by that many (base, size) duple.
* read the counter from linux,drconf-usable-memory
*/
return read_n_cells(n_mem_size_cells, usm);
}
/*
* 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 __be32 *uninitialized_var(dm), *usm;
unsigned int n, rc, ranges, is_kexec_kdump = 0;
unsigned long lmb_size, base, size, sz;
int nid;
struct assoc_arrays aa = { .arrays = NULL };
n = of_get_drconf_memory(memory, &dm);
if (!n)
return;
lmb_size = of_get_lmb_size(memory);
if (!lmb_size)
return;
rc = of_get_assoc_arrays(memory, &aa);
if (rc)
return;
/* check if this is a kexec/kdump kernel */
usm = of_get_usable_memory(memory);
if (usm != NULL)
is_kexec_kdump = 1;
for (; n != 0; --n) {
struct of_drconf_cell drmem;
read_drconf_cell(&drmem, &dm);
/* skip this block if the reserved bit is set in flags (0x80)
or if the block is not assigned to this partition (0x8) */
if ((drmem.flags & DRCONF_MEM_RESERVED)
|| !(drmem.flags & DRCONF_MEM_ASSIGNED))
continue;
base = drmem.base_addr;
size = lmb_size;
ranges = 1;
if (is_kexec_kdump) {
ranges = read_usm_ranges(&usm);
if (!ranges) /* there are no (base, size) duple */
continue;
}
do {
if (is_kexec_kdump) {
base = read_n_cells(n_mem_addr_cells, &usm);
size = read_n_cells(n_mem_size_cells, &usm);
}
nid = of_drconf_to_nid_single(&drmem, &aa);
fake_numa_create_new_node(
((base + size) >> PAGE_SHIFT),
&nid);
node_set_online(nid);
sz = numa_enforce_memory_limit(base, size);
if (sz)
memblock_set_node(base, sz,
&memblock.memory, nid);
} while (--ranges);
}
}
static int __init parse_numa_properties(void)
{
struct device_node *memory;
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) {
struct device_node *cpu;
int nid;
cpu = of_get_cpu_node(i, NULL);
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);
for_each_node_by_type(memory, "memory") {
unsigned long start;
unsigned long size;
int nid;
int ranges;
const __be32 *memcell_buf;
unsigned int len;
memcell_buf = of_get_property(memory,
"linux,usable-memory", &len);
if (!memcell_buf || len <= 0)
memcell_buf = of_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;
fake_numa_create_new_node(((start + size) >> PAGE_SHIFT), &nid);
node_set_online(nid);
if (!(size = numa_enforce_memory_limit(start, size))) {
if (--ranges)
goto new_range;
else
continue;
}
memblock_set_node(start, size, &memblock.memory, nid);
if (--ranges)
goto new_range;
}
/*
* Now do the same thing for each MEMBLOCK 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 = memblock_end_of_DRAM();
unsigned long total_ram = memblock_phys_mem_size();
unsigned long start_pfn, end_pfn;
unsigned int nid = 0;
struct memblock_region *reg;
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_each_memblock(memory, reg) {
start_pfn = memblock_region_memory_base_pfn(reg);
end_pfn = memblock_region_memory_end_pfn(reg);
fake_numa_create_new_node(end_pfn, &nid);
memblock_set_node(PFN_PHYS(start_pfn),
PFN_PHYS(end_pfn - start_pfn),
&memblock.memory, nid);
node_set_online(nid);
}
}
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_cpu_ids; cpu++) {
if (cpumask_test_cpu(cpu,
node_to_cpumask_map[node])) {
if (count == 0)
printk(" %u", cpu);
++count;
} else {
if (count > 1)
printk("-%u", cpu - 1);
count = 0;
}
}
if (count > 1)
printk("-%u", nr_cpu_ids - 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 < memblock_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 memblock 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 virtual address of the memory.
*/
static void __init *careful_zallocation(int nid, unsigned long size,
unsigned long align,
unsigned long end_pfn)
{
void *ret;
int new_nid;
unsigned long ret_paddr;
ret_paddr = __memblock_alloc_base(size, align, end_pfn << PAGE_SHIFT);
/* retry over all memory */
if (!ret_paddr)
ret_paddr = __memblock_alloc_base(size, align, memblock_end_of_DRAM());
if (!ret_paddr)
panic("numa.c: cannot allocate %lu bytes for node %d",
size, nid);
ret = __va(ret_paddr);
/*
* We initialize the nodes in numeric order: 0, 1, 2...
* and hand over control from the MEMBLOCK allocator to the
* bootmem allocator. If this function is called for
* node 5, then we know that all nodes <5 are using the
* bootmem allocator instead of the MEMBLOCK allocator.
*
* So, check the nid from which this allocation came
* and double check to see if we need to use bootmem
* instead of the MEMBLOCK. We don't free the MEMBLOCK memory
* since it would be useless.
*/
new_nid = early_pfn_to_nid(ret_paddr >> PAGE_SHIFT);
if (new_nid < nid) {
ret = __alloc_bootmem_node(NODE_DATA(new_nid),
size, align, 0);
dbg("alloc_bootmem %p %lx\n", ret, size);
}
memset(ret, 0, size);
return ret;
}
static struct notifier_block ppc64_numa_nb = {
.notifier_call = cpu_numa_callback,
.priority = 1 /* Must run before sched domains notifier. */
};
static void __init mark_reserved_regions_for_nid(int nid)
{
struct pglist_data *node = NODE_DATA(nid);
struct memblock_region *reg;
for_each_memblock(reserved, reg) {
unsigned long physbase = reg->base;
unsigned long size = reg->size;
unsigned long start_pfn = physbase >> PAGE_SHIFT;
unsigned long end_pfn = PFN_UP(physbase + size);
struct node_active_region node_ar;
unsigned long node_end_pfn = pgdat_end_pfn(node);
/*
* Check to make sure that this memblock.reserved area is
* within the bounds of the node that we care about.
* Checking the nid of the start and end points is not
* sufficient because the reserved area could span the
* entire node.
*/
if (end_pfn <= node->node_start_pfn ||
start_pfn >= node_end_pfn)
continue;
get_node_active_region(start_pfn, &node_ar);
while (start_pfn < end_pfn &&
node_ar.start_pfn < node_ar.end_pfn) {
unsigned long reserve_size = size;
/*
* if reserved region extends past active region
* then trim size to active region
*/
if (end_pfn > node_ar.end_pfn)
reserve_size = (node_ar.end_pfn << PAGE_SHIFT)
- physbase;
/*
* Only worry about *this* node, others may not
* yet have valid NODE_DATA().
*/
if (node_ar.nid == nid) {
dbg("reserve_bootmem %lx %lx nid=%d\n",
physbase, reserve_size, node_ar.nid);
reserve_bootmem_node(NODE_DATA(node_ar.nid),
physbase, reserve_size,
BOOTMEM_DEFAULT);
}
/*
* if reserved region is contained in the active region
* then done.
*/
if (end_pfn <= node_ar.end_pfn)
break;
/*
* reserved region extends past the active region
* get next active region that contains this
* reserved region
*/
start_pfn = node_ar.end_pfn;
physbase = start_pfn << PAGE_SHIFT;
size = size - reserve_size;
get_node_active_region(start_pfn, &node_ar);
}
}
}
void __init do_init_bootmem(void)
{
int nid;
min_low_pfn = 0;
max_low_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
max_pfn = max_low_pfn;
if (parse_numa_properties())
setup_nonnuma();
else
dump_numa_memory_topology();
for_each_online_node(nid) {
unsigned long start_pfn, end_pfn;
void *bootmem_vaddr;
unsigned long bootmap_pages;
get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
/*
* Allocate the node structure node local if possible
*
* Be careful moving this around, as it relies on all
* previous nodes' bootmem to be initialized and have
* all reserved areas marked.
*/
NODE_DATA(nid) = careful_zallocation(nid,
sizeof(struct pglist_data),
SMP_CACHE_BYTES, end_pfn);
dbg("node %d\n", nid);
dbg("NODE_DATA() = %p\n", NODE_DATA(nid));
NODE_DATA(nid)->bdata = &bootmem_node_data[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_vaddr = careful_zallocation(nid,
bootmap_pages << PAGE_SHIFT,
PAGE_SIZE, end_pfn);
dbg("bootmap_vaddr = %p\n", bootmem_vaddr);
init_bootmem_node(NODE_DATA(nid),
__pa(bootmem_vaddr) >> PAGE_SHIFT,
start_pfn, end_pfn);
free_bootmem_with_active_regions(nid, end_pfn);
/*
* Be very careful about moving this around. Future
* calls to careful_zallocation() depend on this getting
* done correctly.
*/
mark_reserved_regions_for_nid(nid);
sparse_memory_present_with_active_regions(nid);
}
init_bootmem_done = 1;
/*
* Now bootmem is initialised we can create the node to cpumask
* lookup tables and setup the cpu callback to populate them.
*/
setup_node_to_cpumask_map();
reset_numa_cpu_lookup_table();
register_cpu_notifier(&ppc64_numa_nb);
cpu_numa_callback(&ppc64_numa_nb, CPU_UP_PREPARE,
(void *)(unsigned long)boot_cpuid);
}
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] = memblock_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;
p = strstr(p, "fake=");
if (p)
cmdline = p + strlen("fake=");
return 0;
}
early_param("numa", early_numa);
#ifdef CONFIG_MEMORY_HOTPLUG
/*
* Find the node associated with a hot added memory section for
* memory represented in the device tree by the property
* ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory.
*/
static int hot_add_drconf_scn_to_nid(struct device_node *memory,
unsigned long scn_addr)
{
const __be32 *dm;
unsigned int drconf_cell_cnt, rc;
unsigned long lmb_size;
struct assoc_arrays aa;
int nid = -1;
drconf_cell_cnt = of_get_drconf_memory(memory, &dm);
if (!drconf_cell_cnt)
return -1;
lmb_size = of_get_lmb_size(memory);
if (!lmb_size)
return -1;
rc = of_get_assoc_arrays(memory, &aa);
if (rc)
return -1;
for (; drconf_cell_cnt != 0; --drconf_cell_cnt) {
struct of_drconf_cell drmem;
read_drconf_cell(&drmem, &dm);
/* skip this block if it is reserved or not assigned to
* this partition */
if ((drmem.flags & DRCONF_MEM_RESERVED)
|| !(drmem.flags & DRCONF_MEM_ASSIGNED))
continue;
if ((scn_addr < drmem.base_addr)
|| (scn_addr >= (drmem.base_addr + lmb_size)))
continue;
nid = of_drconf_to_nid_single(&drmem, &aa);
break;
}
return nid;
}
/*
* Find the node associated with a hot added memory section for memory
* represented in the device tree as a node (i.e. memory@XXXX) for
* each memblock.
*/
static int hot_add_node_scn_to_nid(unsigned long scn_addr)
{
struct device_node *memory;
int nid = -1;
for_each_node_by_type(memory, "memory") {
unsigned long start, size;
int ranges;
const __be32 *memcell_buf;
unsigned int len;
memcell_buf = of_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);
while (ranges--) {
start = read_n_cells(n_mem_addr_cells, &memcell_buf);
size = read_n_cells(n_mem_size_cells, &memcell_buf);
if ((scn_addr < start) || (scn_addr >= (start + size)))
continue;
nid = of_node_to_nid_single(memory);
break;
}
if (nid >= 0)
break;
}
of_node_put(memory);
return nid;
}
/*
* Find the node associated with a hot added memory section. Section
* corresponds to a SPARSEMEM section, not an MEMBLOCK. It is assumed that
* sections are fully contained within a single MEMBLOCK.
*/
int hot_add_scn_to_nid(unsigned long scn_addr)
{
struct device_node *memory = NULL;
int nid, found = 0;
if (!numa_enabled || (min_common_depth < 0))
return first_online_node;
memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
if (memory) {
nid = hot_add_drconf_scn_to_nid(memory, scn_addr);
of_node_put(memory);
} else {
nid = hot_add_node_scn_to_nid(scn_addr);
}
if (nid < 0 || !node_online(nid))
nid = first_online_node;
if (NODE_DATA(nid)->node_spanned_pages)
return nid;
for_each_online_node(nid) {
if (NODE_DATA(nid)->node_spanned_pages) {
found = 1;
break;
}
}
BUG_ON(!found);
return nid;
}
static u64 hot_add_drconf_memory_max(void)
{
struct device_node *memory = NULL;
unsigned int drconf_cell_cnt = 0;
u64 lmb_size = 0;
const __be32 *dm = NULL;
memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
if (memory) {
drconf_cell_cnt = of_get_drconf_memory(memory, &dm);
lmb_size = of_get_lmb_size(memory);
of_node_put(memory);
}
return lmb_size * drconf_cell_cnt;
}
/*
* memory_hotplug_max - return max address of memory that may be added
*
* This is currently only used on systems that support drconfig memory
* hotplug.
*/
u64 memory_hotplug_max(void)
{
return max(hot_add_drconf_memory_max(), memblock_end_of_DRAM());
}
#endif /* CONFIG_MEMORY_HOTPLUG */
/* Virtual Processor Home Node (VPHN) support */
#ifdef CONFIG_PPC_SPLPAR
struct topology_update_data {
struct topology_update_data *next;
unsigned int cpu;
int old_nid;
int new_nid;
};
static u8 vphn_cpu_change_counts[NR_CPUS][MAX_DISTANCE_REF_POINTS];
static cpumask_t cpu_associativity_changes_mask;
static int vphn_enabled;
static int prrn_enabled;
static void reset_topology_timer(void);
/*
* Store the current values of the associativity change counters in the
* hypervisor.
*/
static void setup_cpu_associativity_change_counters(void)
{
int cpu;
/* The VPHN feature supports a maximum of 8 reference points */
BUILD_BUG_ON(MAX_DISTANCE_REF_POINTS > 8);
for_each_possible_cpu(cpu) {
int i;
u8 *counts = vphn_cpu_change_counts[cpu];
volatile u8 *hypervisor_counts = lppaca[cpu].vphn_assoc_counts;
for (i = 0; i < distance_ref_points_depth; i++)
counts[i] = hypervisor_counts[i];
}
}
/*
* The hypervisor maintains a set of 8 associativity change counters in
* the VPA of each cpu that correspond to the associativity levels in the
* ibm,associativity-reference-points property. When an associativity
* level changes, the corresponding counter is incremented.
*
* Set a bit in cpu_associativity_changes_mask for each cpu whose home
* node associativity levels have changed.
*
* Returns the number of cpus with unhandled associativity changes.
*/
static int update_cpu_associativity_changes_mask(void)
{
int cpu;
cpumask_t *changes = &cpu_associativity_changes_mask;
for_each_possible_cpu(cpu) {
int i, changed = 0;
u8 *counts = vphn_cpu_change_counts[cpu];
volatile u8 *hypervisor_counts = lppaca[cpu].vphn_assoc_counts;
for (i = 0; i < distance_ref_points_depth; i++) {
if (hypervisor_counts[i] != counts[i]) {
counts[i] = hypervisor_counts[i];
changed = 1;
}
}
if (changed) {
cpumask_or(changes, changes, cpu_sibling_mask(cpu));
cpu = cpu_last_thread_sibling(cpu);
}
}
return cpumask_weight(changes);
}
/*
* 6 64-bit registers unpacked into 12 32-bit associativity values. To form
* the complete property we have to add the length in the first cell.
*/
#define VPHN_ASSOC_BUFSIZE (6*sizeof(u64)/sizeof(u32) + 1)
/*
* Convert the associativity domain numbers returned from the hypervisor
* to the sequence they would appear in the ibm,associativity property.
*/
static int vphn_unpack_associativity(const long *packed, __be32 *unpacked)
{
int i, nr_assoc_doms = 0;
const __be16 *field = (const __be16 *) packed;
#define VPHN_FIELD_UNUSED (0xffff)
#define VPHN_FIELD_MSB (0x8000)
#define VPHN_FIELD_MASK (~VPHN_FIELD_MSB)
for (i = 1; i < VPHN_ASSOC_BUFSIZE; i++) {
if (be16_to_cpup(field) == VPHN_FIELD_UNUSED) {
/* All significant fields processed, and remaining
* fields contain the reserved value of all 1's.
* Just store them.
*/
unpacked[i] = *((__be32 *)field);
field += 2;
} else if (be16_to_cpup(field) & VPHN_FIELD_MSB) {
/* Data is in the lower 15 bits of this field */
unpacked[i] = cpu_to_be32(
be16_to_cpup(field) & VPHN_FIELD_MASK);
field++;
nr_assoc_doms++;
} else {
/* Data is in the lower 15 bits of this field
* concatenated with the next 16 bit field
*/
unpacked[i] = *((__be32 *)field);
field += 2;
nr_assoc_doms++;
}
}
/* The first cell contains the length of the property */
unpacked[0] = cpu_to_be32(nr_assoc_doms);
return nr_assoc_doms;
}
/*
* Retrieve the new associativity information for a virtual processor's
* home node.
*/
static long hcall_vphn(unsigned long cpu, __be32 *associativity)
{
long rc;
long retbuf[PLPAR_HCALL9_BUFSIZE] = {0};
u64 flags = 1;
int hwcpu = get_hard_smp_processor_id(cpu);
rc = plpar_hcall9(H_HOME_NODE_ASSOCIATIVITY, retbuf, flags, hwcpu);
vphn_unpack_associativity(retbuf, associativity);
return rc;
}
static long vphn_get_associativity(unsigned long cpu,
__be32 *associativity)
{
long rc;
rc = hcall_vphn(cpu, associativity);
switch (rc) {
case H_FUNCTION:
printk(KERN_INFO
"VPHN is not supported. Disabling polling...\n");
stop_topology_update();
break;
case H_HARDWARE:
printk(KERN_ERR
"hcall_vphn() experienced a hardware fault "
"preventing VPHN. Disabling polling...\n");
stop_topology_update();
}
return rc;
}
/*
* Update the CPU maps and sysfs entries for a single CPU when its NUMA
* characteristics change. This function doesn't perform any locking and is
* only safe to call from stop_machine().
*/
static int update_cpu_topology(void *data)
{
struct topology_update_data *update;
unsigned long cpu;
if (!data)
return -EINVAL;
cpu = smp_processor_id();
for (update = data; update; update = update->next) {
if (cpu != update->cpu)
continue;
unmap_cpu_from_node(update->cpu);
map_cpu_to_node(update->cpu, update->new_nid);
vdso_getcpu_init();
}
return 0;
}
static int update_lookup_table(void *data)
{
struct topology_update_data *update;
if (!data)
return -EINVAL;
/*
* Upon topology update, the numa-cpu lookup table needs to be updated
* for all threads in the core, including offline CPUs, to ensure that
* future hotplug operations respect the cpu-to-node associativity
* properly.
*/
for (update = data; update; update = update->next) {
int nid, base, j;
nid = update->new_nid;
base = cpu_first_thread_sibling(update->cpu);
for (j = 0; j < threads_per_core; j++) {
update_numa_cpu_lookup_table(base + j, nid);
}
}
return 0;
}
/*
* Update the node maps and sysfs entries for each cpu whose home node
* has changed. Returns 1 when the topology has changed, and 0 otherwise.
*/
int arch_update_cpu_topology(void)
{
unsigned int cpu, sibling, changed = 0;
struct topology_update_data *updates, *ud;
__be32 associativity[VPHN_ASSOC_BUFSIZE] = {0};
cpumask_t updated_cpus;
struct device *dev;
int weight, new_nid, i = 0;
weight = cpumask_weight(&cpu_associativity_changes_mask);
if (!weight)
return 0;
updates = kzalloc(weight * (sizeof(*updates)), GFP_KERNEL);
if (!updates)
return 0;
cpumask_clear(&updated_cpus);
for_each_cpu(cpu, &cpu_associativity_changes_mask) {
/*
* If siblings aren't flagged for changes, updates list
* will be too short. Skip on this update and set for next
* update.
*/
if (!cpumask_subset(cpu_sibling_mask(cpu),
&cpu_associativity_changes_mask)) {
pr_info("Sibling bits not set for associativity "
"change, cpu%d\n", cpu);
cpumask_or(&cpu_associativity_changes_mask,
&cpu_associativity_changes_mask,
cpu_sibling_mask(cpu));
cpu = cpu_last_thread_sibling(cpu);
continue;
}
/* Use associativity from first thread for all siblings */
vphn_get_associativity(cpu, associativity);
new_nid = associativity_to_nid(associativity);
if (new_nid < 0 || !node_online(new_nid))
new_nid = first_online_node;
if (new_nid == numa_cpu_lookup_table[cpu]) {
cpumask_andnot(&cpu_associativity_changes_mask,
&cpu_associativity_changes_mask,
cpu_sibling_mask(cpu));
cpu = cpu_last_thread_sibling(cpu);
continue;
}
for_each_cpu(sibling, cpu_sibling_mask(cpu)) {
ud = &updates[i++];
ud->cpu = sibling;
ud->new_nid = new_nid;
ud->old_nid = numa_cpu_lookup_table[sibling];
cpumask_set_cpu(sibling, &updated_cpus);
if (i < weight)
ud->next = &updates[i];
}
cpu = cpu_last_thread_sibling(cpu);
}
stop_machine(update_cpu_topology, &updates[0], &updated_cpus);
/*
* Update the numa-cpu lookup table with the new mappings, even for
* offline CPUs. It is best to perform this update from the stop-
* machine context.
*/
stop_machine(update_lookup_table, &updates[0],
cpumask_of(raw_smp_processor_id()));
for (ud = &updates[0]; ud; ud = ud->next) {
unregister_cpu_under_node(ud->cpu, ud->old_nid);
register_cpu_under_node(ud->cpu, ud->new_nid);
dev = get_cpu_device(ud->cpu);
if (dev)
kobject_uevent(&dev->kobj, KOBJ_CHANGE);
cpumask_clear_cpu(ud->cpu, &cpu_associativity_changes_mask);
changed = 1;
}
kfree(updates);
return changed;
}
static void topology_work_fn(struct work_struct *work)
{
rebuild_sched_domains();
}
static DECLARE_WORK(topology_work, topology_work_fn);
static void topology_schedule_update(void)
{
schedule_work(&topology_work);
}
static void topology_timer_fn(unsigned long ignored)
{
if (prrn_enabled && cpumask_weight(&cpu_associativity_changes_mask))
topology_schedule_update();
else if (vphn_enabled) {
if (update_cpu_associativity_changes_mask() > 0)
topology_schedule_update();
reset_topology_timer();
}
}
static struct timer_list topology_timer =
TIMER_INITIALIZER(topology_timer_fn, 0, 0);
static void reset_topology_timer(void)
{
topology_timer.data = 0;
topology_timer.expires = jiffies + 60 * HZ;
mod_timer(&topology_timer, topology_timer.expires);
}
#ifdef CONFIG_SMP
static void stage_topology_update(int core_id)
{
cpumask_or(&cpu_associativity_changes_mask,
&cpu_associativity_changes_mask, cpu_sibling_mask(core_id));
reset_topology_timer();
}
static int dt_update_callback(struct notifier_block *nb,
unsigned long action, void *data)
{
struct of_prop_reconfig *update;
int rc = NOTIFY_DONE;
switch (action) {
case OF_RECONFIG_UPDATE_PROPERTY:
update = (struct of_prop_reconfig *)data;
if (!of_prop_cmp(update->dn->type, "cpu") &&
!of_prop_cmp(update->prop->name, "ibm,associativity")) {
u32 core_id;
of_property_read_u32(update->dn, "reg", &core_id);
stage_topology_update(core_id);
rc = NOTIFY_OK;
}
break;
}
return rc;
}
static struct notifier_block dt_update_nb = {
.notifier_call = dt_update_callback,
};
#endif
/*
* Start polling for associativity changes.
*/
int start_topology_update(void)
{
int rc = 0;
if (firmware_has_feature(FW_FEATURE_PRRN)) {
if (!prrn_enabled) {
prrn_enabled = 1;
vphn_enabled = 0;
#ifdef CONFIG_SMP
rc = of_reconfig_notifier_register(&dt_update_nb);
#endif
}
} else if (firmware_has_feature(FW_FEATURE_VPHN) &&
lppaca_shared_proc(get_lppaca())) {
if (!vphn_enabled) {
prrn_enabled = 0;
vphn_enabled = 1;
setup_cpu_associativity_change_counters();
init_timer_deferrable(&topology_timer);
reset_topology_timer();
}
}
return rc;
}
/*
* Disable polling for VPHN associativity changes.
*/
int stop_topology_update(void)
{
int rc = 0;
if (prrn_enabled) {
prrn_enabled = 0;
#ifdef CONFIG_SMP
rc = of_reconfig_notifier_unregister(&dt_update_nb);
#endif
} else if (vphn_enabled) {
vphn_enabled = 0;
rc = del_timer_sync(&topology_timer);
}
return rc;
}
int prrn_is_enabled(void)
{
return prrn_enabled;
}
static int topology_read(struct seq_file *file, void *v)
{
if (vphn_enabled || prrn_enabled)
seq_puts(file, "on\n");
else
seq_puts(file, "off\n");
return 0;
}
static int topology_open(struct inode *inode, struct file *file)
{
return single_open(file, topology_read, NULL);
}
static ssize_t topology_write(struct file *file, const char __user *buf,
size_t count, loff_t *off)
{
char kbuf[4]; /* "on" or "off" plus null. */
int read_len;
read_len = count < 3 ? count : 3;
if (copy_from_user(kbuf, buf, read_len))
return -EINVAL;
kbuf[read_len] = '\0';
if (!strncmp(kbuf, "on", 2))
start_topology_update();
else if (!strncmp(kbuf, "off", 3))
stop_topology_update();
else
return -EINVAL;
return count;
}
static const struct file_operations topology_ops = {
.read = seq_read,
.write = topology_write,
.open = topology_open,
.release = single_release
};
static int topology_update_init(void)
{
start_topology_update();
proc_create("powerpc/topology_updates", 0644, NULL, &topology_ops);
return 0;
}
device_initcall(topology_update_init);
#endif /* CONFIG_PPC_SPLPAR */