/* * pSeries NUMA support * * Copyright (C) 2002 Anton Blanchard , 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include 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 %u 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 = NUMA_NO_NODE; 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 = NUMA_NO_NODE; 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 = NUMA_NO_NODE; 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 = NUMA_NO_NODE; 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 = NUMA_NO_NODE; 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_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid); if (!nd_pa) panic("Cannot allocate %zu bytes for node %d data\n", nd_size, 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 = NUMA_NO_NODE; 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 = NUMA_NO_NODE; 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_node_is_type(update->dn, "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 (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(); } } pr_info("Starting topology update%s%s\n", (prrn_enabled ? " prrn_enabled" : ""), (vphn_enabled ? " vphn_enabled" : "")); 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 } if (vphn_enabled) { vphn_enabled = 0; rc = del_timer_sync(&topology_timer); } pr_info("Stopping topology update\n"); 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)) 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) { /* Do not poll for changes if disabled at boot */ if (topology_updates_enabled) 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 */