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Diffstat (limited to 'arch/powerpc/mm/numa.c')
| -rw-r--r-- | arch/powerpc/mm/numa.c | 1621 |
1 files changed, 1621 insertions, 0 deletions
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c new file mode 100644 index 000000000..f473c05e9 --- /dev/null +++ b/arch/powerpc/mm/numa.c @@ -0,0 +1,1621 @@ +/* + * 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. + */ +#define pr_fmt(fmt) "numa: " fmt + +#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> +#include <asm/drmem.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_each_node(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; +} + +static void reset_numa_cpu_lookup_table(void) +{ + unsigned int cpu; + + for_each_possible_cpu(cpu) + numa_cpu_lookup_table[cpu] = -1; +} + +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); +} + +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; +} +EXPORT_SYMBOL(__node_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]) - 1]; + 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) { + /* + * Skip the length field and send start of associativity array + */ + initialize_distance_lookup_table(nid, associativity + 1); + } + +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) +{ + int nid = -1; + + of_node_get(device); + while (device) { + nid = of_node_to_nid_single(device); + if (nid != -1) + break; + + device = of_get_next_parent(device); + } + of_node_put(device); + + return nid; +} +EXPORT_SYMBOL(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; +} + +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 assoc_arrays *aa) +{ + struct device_node *memory; + const __be32 *prop; + u32 len; + + memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory"); + if (!memory) + return -1; + + prop = of_get_property(memory, "ibm,associativity-lookup-arrays", &len); + if (!prop || len < 2 * sizeof(unsigned int)) { + of_node_put(memory); + return -1; + } + + aa->n_arrays = of_read_number(prop++, 1); + aa->array_sz = of_read_number(prop++, 1); + + of_node_put(memory); + + /* 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 drmem_lmb *lmb) +{ + struct assoc_arrays aa = { .arrays = NULL }; + int default_nid = 0; + int nid = default_nid; + int rc, index; + + rc = of_get_assoc_arrays(&aa); + if (rc) + return default_nid; + + if (min_common_depth > 0 && min_common_depth <= aa.array_sz && + !(lmb->flags & DRCONF_MEM_AI_INVALID) && + lmb->aa_index < aa.n_arrays) { + index = lmb->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; + + if (nid > 0) { + index = lmb->aa_index * aa.array_sz; + initialize_distance_lookup_table(nid, + &aa.arrays[index]); + } + } + + 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 = -1; + 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); + if (cpu_present(lcpu)) + goto out_present; + else + goto out; + } + + nid = of_node_to_nid_single(cpu); + +out_present: + if (nid < 0 || !node_possible(nid)) + nid = first_online_node; + + map_cpu_to_node(lcpu, nid); + of_node_put(cpu); +out: + 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; + } + } +} + +/* Must run before sched domains notifier. */ +static int ppc_numa_cpu_prepare(unsigned int cpu) +{ + int nid; + + nid = numa_setup_cpu(cpu); + verify_cpu_node_mapping(cpu, nid); + return 0; +} + +static int ppc_numa_cpu_dead(unsigned int cpu) +{ +#ifdef CONFIG_HOTPLUG_CPU + unmap_cpu_from_node(cpu); +#endif + return 0; +} + +/* + * 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 numa_setup_drmem_lmb(struct drmem_lmb *lmb, + const __be32 **usm) +{ + unsigned int ranges, is_kexec_kdump = 0; + unsigned long base, size, sz; + int nid; + + /* + * Skip this block if the reserved bit is set in flags (0x80) + * or if the block is not assigned to this partition (0x8) + */ + if ((lmb->flags & DRCONF_MEM_RESERVED) + || !(lmb->flags & DRCONF_MEM_ASSIGNED)) + return; + + if (*usm) + is_kexec_kdump = 1; + + base = lmb->base_addr; + size = drmem_lmb_size(); + ranges = 1; + + if (is_kexec_kdump) { + ranges = read_usm_ranges(usm); + if (!ranges) /* there are no (base, size) duple */ + return; + } + + 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(lmb); + 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); + + size = numa_enforce_memory_limit(start, size); + if (size) + 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) { + walk_drmem_lmbs(memory, numa_setup_drmem_lmb); + of_node_put(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) { + pr_info("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) + pr_cont(" %u", cpu); + ++count; + } else { + if (count > 1) + pr_cont("-%u", cpu - 1); + count = 0; + } + } + + if (count > 1) + pr_cont("-%u", nr_cpu_ids - 1); + pr_cont("\n"); + } +} + +/* Initialize NODE_DATA for a node on the local memory */ +static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn) +{ + u64 spanned_pages = end_pfn - start_pfn; + const size_t nd_size = roundup(sizeof(pg_data_t), SMP_CACHE_BYTES); + u64 nd_pa; + void *nd; + int tnid; + + nd_pa = memblock_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid); + nd = __va(nd_pa); + + /* report and initialize */ + pr_info(" NODE_DATA [mem %#010Lx-%#010Lx]\n", + nd_pa, nd_pa + nd_size - 1); + tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT); + if (tnid != nid) + pr_info(" NODE_DATA(%d) on node %d\n", nid, tnid); + + node_data[nid] = nd; + memset(NODE_DATA(nid), 0, sizeof(pg_data_t)); + NODE_DATA(nid)->node_id = nid; + NODE_DATA(nid)->node_start_pfn = start_pfn; + NODE_DATA(nid)->node_spanned_pages = spanned_pages; +} + +static void __init find_possible_nodes(void) +{ + struct device_node *rtas; + u32 numnodes, i; + + if (min_common_depth <= 0) + return; + + rtas = of_find_node_by_path("/rtas"); + if (!rtas) + return; + + if (of_property_read_u32_index(rtas, + "ibm,max-associativity-domains", + min_common_depth, &numnodes)) + goto out; + + for (i = 0; i < numnodes; i++) { + if (!node_possible(i)) + node_set(i, node_possible_map); + } + +out: + of_node_put(rtas); +} + +void __init mem_topology_setup(void) +{ + int cpu; + + if (parse_numa_properties()) + setup_nonnuma(); + + /* + * Modify the set of possible NUMA nodes to reflect information + * available about the set of online nodes, and the set of nodes + * that we expect to make use of for this platform's affinity + * calculations. + */ + nodes_and(node_possible_map, node_possible_map, node_online_map); + + find_possible_nodes(); + + setup_node_to_cpumask_map(); + + reset_numa_cpu_lookup_table(); + + for_each_present_cpu(cpu) + numa_setup_cpu(cpu); +} + +void __init initmem_init(void) +{ + int nid; + + max_low_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; + max_pfn = max_low_pfn; + + memblock_dump_all(); + + for_each_online_node(nid) { + unsigned long start_pfn, end_pfn; + + get_pfn_range_for_nid(nid, &start_pfn, &end_pfn); + setup_node_data(nid, start_pfn, end_pfn); + sparse_memory_present_with_active_regions(nid); + } + + sparse_init(); + + /* + * We need the numa_cpu_lookup_table to be accurate for all CPUs, + * even before we online them, so that we can use cpu_to_{node,mem} + * early in boot, cf. smp_prepare_cpus(). + * _nocalls() + manual invocation is used because cpuhp is not yet + * initialized for the boot CPU. + */ + cpuhp_setup_state_nocalls(CPUHP_POWER_NUMA_PREPARE, "powerpc/numa:prepare", + ppc_numa_cpu_prepare, ppc_numa_cpu_dead); +} + +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); + +static bool topology_updates_enabled = true; + +static int __init early_topology_updates(char *p) +{ + if (!p) + return 0; + + if (!strcmp(p, "off")) { + pr_info("Disabling topology updates\n"); + topology_updates_enabled = false; + } + + return 0; +} +early_param("topology_updates", early_topology_updates); + +#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(unsigned long scn_addr) +{ + struct drmem_lmb *lmb; + unsigned long lmb_size; + int nid = -1; + + lmb_size = drmem_lmb_size(); + + for_each_drmem_lmb(lmb) { + /* skip this block if it is reserved or not assigned to + * this partition */ + if ((lmb->flags & DRCONF_MEM_RESERVED) + || !(lmb->flags & DRCONF_MEM_ASSIGNED)) + continue; + + if ((scn_addr < lmb->base_addr) + || (scn_addr >= (lmb->base_addr + lmb_size))) + continue; + + nid = of_drconf_to_nid_single(lmb); + 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; + + 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(scn_addr); + of_node_put(memory); + } else { + nid = hot_add_node_scn_to_nid(scn_addr); + } + + if (nid < 0 || !node_possible(nid)) + nid = first_online_node; + + return nid; +} + +static u64 hot_add_drconf_memory_max(void) +{ + struct device_node *memory = NULL; + struct device_node *dn = NULL; + const __be64 *lrdr = NULL; + + dn = of_find_node_by_path("/rtas"); + if (dn) { + lrdr = of_get_property(dn, "ibm,lrdr-capacity", NULL); + of_node_put(dn); + if (lrdr) + return be64_to_cpup(lrdr); + } + + memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory"); + if (memory) { + of_node_put(memory); + return drmem_lmb_memory_max(); + } + return 0; +} + +/* + * 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 + +#include "vphn.h" + +struct topology_update_data { + struct topology_update_data *next; + unsigned int cpu; + int old_nid; + int new_nid; +}; + +#define TOPOLOGY_DEF_TIMER_SECS 60 + +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); +static int topology_timer_secs = 1; +static int topology_inited; + +/* + * Change polling interval for associativity changes. + */ +int timed_topology_update(int nsecs) +{ + if (vphn_enabled) { + if (nsecs > 0) + topology_timer_secs = nsecs; + else + topology_timer_secs = TOPOLOGY_DEF_TIMER_SECS; + + reset_topology_timer(); + } + + return 0; +} + +/* + * 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_of(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_of(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); +} + +/* + * 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_once(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(); + break; + case H_SUCCESS: + dbg("VPHN hcall succeeded. Reset polling...\n"); + timed_topology_update(0); + break; + } + + return rc; +} + +int find_and_online_cpu_nid(int cpu) +{ + __be32 associativity[VPHN_ASSOC_BUFSIZE] = {0}; + int new_nid; + + /* Use associativity from first thread for all siblings */ + if (vphn_get_associativity(cpu, associativity)) + return cpu_to_node(cpu); + + new_nid = associativity_to_nid(associativity); + if (new_nid < 0 || !node_possible(new_nid)) + new_nid = first_online_node; + + if (NODE_DATA(new_nid) == NULL) { +#ifdef CONFIG_MEMORY_HOTPLUG + /* + * Need to ensure that NODE_DATA is initialized for a node from + * available memory (see memblock_alloc_try_nid). If unable to + * init the node, then default to nearest node that has memory + * installed. Skip onlining a node if the subsystems are not + * yet initialized. + */ + if (!topology_inited || try_online_node(new_nid)) + new_nid = first_online_node; +#else + /* + * Default to using the nearest node that has memory installed. + * Otherwise, it would be necessary to patch the kernel MM code + * to deal with more memoryless-node error conditions. + */ + new_nid = first_online_node; +#endif + } + + pr_debug("%s:%d cpu %d nid %d\n", __FUNCTION__, __LINE__, + cpu, new_nid); + return new_nid; +} + +/* + * 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) { + int new_nid = update->new_nid; + if (cpu != update->cpu) + continue; + + unmap_cpu_from_node(cpu); + map_cpu_to_node(cpu, new_nid); + set_cpu_numa_node(cpu, new_nid); + set_cpu_numa_mem(cpu, local_memory_node(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. + * + * cpus_locked says whether we already hold cpu_hotplug_lock. + */ +int numa_update_cpu_topology(bool cpus_locked) +{ + unsigned int cpu, sibling, changed = 0; + struct topology_update_data *updates, *ud; + cpumask_t updated_cpus; + struct device *dev; + int weight, new_nid, i = 0; + + if (!prrn_enabled && !vphn_enabled && topology_inited) + return 0; + + weight = cpumask_weight(&cpu_associativity_changes_mask); + if (!weight) + return 0; + + updates = kcalloc(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; + } + + new_nid = find_and_online_cpu_nid(cpu); + + if (new_nid == numa_cpu_lookup_table[cpu]) { + cpumask_andnot(&cpu_associativity_changes_mask, + &cpu_associativity_changes_mask, + cpu_sibling_mask(cpu)); + dbg("Assoc chg gives same node %d for cpu%d\n", + new_nid, cpu); + cpu = cpu_last_thread_sibling(cpu); + continue; + } + + for_each_cpu(sibling, cpu_sibling_mask(cpu)) { + ud = &updates[i++]; + ud->next = &updates[i]; + ud->cpu = sibling; + ud->new_nid = new_nid; + ud->old_nid = numa_cpu_lookup_table[sibling]; + cpumask_set_cpu(sibling, &updated_cpus); + } + cpu = cpu_last_thread_sibling(cpu); + } + + /* + * Prevent processing of 'updates' from overflowing array + * where last entry filled in a 'next' pointer. + */ + if (i) + updates[i-1].next = NULL; + + pr_debug("Topology update for the following CPUs:\n"); + if (cpumask_weight(&updated_cpus)) { + for (ud = &updates[0]; ud; ud = ud->next) { + pr_debug("cpu %d moving from node %d " + "to %d\n", ud->cpu, + ud->old_nid, ud->new_nid); + } + } + + /* + * In cases where we have nothing to update (because the updates list + * is too short or because the new topology is same as the old one), + * skip invoking update_cpu_topology() via stop-machine(). This is + * necessary (and not just a fast-path optimization) since stop-machine + * can end up electing a random CPU to run update_cpu_topology(), and + * thus trick us into setting up incorrect cpu-node mappings (since + * 'updates' is kzalloc()'ed). + * + * And for the similar reason, we will skip all the following updating. + */ + if (!cpumask_weight(&updated_cpus)) + goto out; + + if (cpus_locked) + stop_machine_cpuslocked(update_cpu_topology, &updates[0], + &updated_cpus); + else + 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. + */ + if (cpus_locked) + stop_machine_cpuslocked(update_lookup_table, &updates[0], + cpumask_of(raw_smp_processor_id())); + else + 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; + } + +out: + kfree(updates); + return changed; +} + +int arch_update_cpu_topology(void) +{ + return numa_update_cpu_topology(true); +} + +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(struct timer_list *unused) +{ + 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; + +static void reset_topology_timer(void) +{ + if (vphn_enabled) + mod_timer(&topology_timer, jiffies + topology_timer_secs * HZ); +} + +#ifdef CONFIG_SMP + +static int dt_update_callback(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct of_reconfig_data *update = data; + int rc = NOTIFY_DONE; + + switch (action) { + case OF_RECONFIG_UPDATE_PROPERTY: + 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); + rc = dlpar_cpu_readd(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 (!topology_updates_enabled) + return 0; + + if (firmware_has_feature(FW_FEATURE_PRRN)) { + if (!prrn_enabled) { + prrn_enabled = 1; +#ifdef CONFIG_SMP + rc = of_reconfig_notifier_register(&dt_update_nb); +#endif + } + } + if (firmware_has_feature(FW_FEATURE_VPHN) && + lppaca_shared_proc(get_lppaca())) { + if (!vphn_enabled) { + vphn_enabled = 1; + setup_cpu_associativity_change_counters(); + timer_setup(&topology_timer, topology_timer_fn, + TIMER_DEFERRABLE); + reset_topology_timer(); + } + } + + return rc; +} + +/* + * Disable polling for VPHN associativity changes. + */ +int stop_topology_update(void) +{ + int rc = 0; + + if (!topology_updates_enabled) + return 0; + + if (prrn_enabled) { + prrn_enabled = 0; +#ifdef CONFIG_SMP + rc = of_reconfig_notifier_unregister(&dt_update_nb); +#endif + } + if (vphn_enabled) { + vphn_enabled = 0; + rc = del_timer_sync(&topology_timer); + } + + return rc; +} + +int prrn_is_enabled(void) +{ + return prrn_enabled; +} + +void __init shared_proc_topology_init(void) +{ + if (lppaca_shared_proc(get_lppaca())) { + bitmap_fill(cpumask_bits(&cpu_associativity_changes_mask), + nr_cpumask_bits); + numa_update_cpu_topology(false); + } +} + +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)) { + topology_updates_enabled = true; + start_topology_update(); + } else if (!strncmp(kbuf, "off", 3)) { + stop_topology_update(); + topology_updates_enabled = false; + } 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(); + + if (vphn_enabled) + topology_schedule_update(); + + if (!proc_create("powerpc/topology_updates", 0644, NULL, &topology_ops)) + return -ENOMEM; + + topology_inited = 1; + return 0; +} +device_initcall(topology_update_init); +#endif /* CONFIG_PPC_SPLPAR */ |