diff options
Diffstat (limited to 'arch/x86/mm/srat_64.c')
| -rw-r--r-- | arch/x86/mm/srat_64.c | 566 |
1 files changed, 566 insertions, 0 deletions
diff --git a/arch/x86/mm/srat_64.c b/arch/x86/mm/srat_64.c new file mode 100644 index 00000000000..acdf03e1914 --- /dev/null +++ b/arch/x86/mm/srat_64.c @@ -0,0 +1,566 @@ +/* + * ACPI 3.0 based NUMA setup + * Copyright 2004 Andi Kleen, SuSE Labs. + * + * Reads the ACPI SRAT table to figure out what memory belongs to which CPUs. + * + * Called from acpi_numa_init while reading the SRAT and SLIT tables. + * Assumes all memory regions belonging to a single proximity domain + * are in one chunk. Holes between them will be included in the node. + */ + +#include <linux/kernel.h> +#include <linux/acpi.h> +#include <linux/mmzone.h> +#include <linux/bitmap.h> +#include <linux/module.h> +#include <linux/topology.h> +#include <linux/bootmem.h> +#include <linux/mm.h> +#include <asm/proto.h> +#include <asm/numa.h> +#include <asm/e820.h> + +int acpi_numa __initdata; + +static struct acpi_table_slit *acpi_slit; + +static nodemask_t nodes_parsed __initdata; +static struct bootnode nodes[MAX_NUMNODES] __initdata; +static struct bootnode nodes_add[MAX_NUMNODES]; +static int found_add_area __initdata; +int hotadd_percent __initdata = 0; + +/* Too small nodes confuse the VM badly. Usually they result + from BIOS bugs. */ +#define NODE_MIN_SIZE (4*1024*1024) + +static __init int setup_node(int pxm) +{ + return acpi_map_pxm_to_node(pxm); +} + +static __init int conflicting_nodes(unsigned long start, unsigned long end) +{ + int i; + for_each_node_mask(i, nodes_parsed) { + struct bootnode *nd = &nodes[i]; + if (nd->start == nd->end) + continue; + if (nd->end > start && nd->start < end) + return i; + if (nd->end == end && nd->start == start) + return i; + } + return -1; +} + +static __init void cutoff_node(int i, unsigned long start, unsigned long end) +{ + struct bootnode *nd = &nodes[i]; + + if (found_add_area) + return; + + if (nd->start < start) { + nd->start = start; + if (nd->end < nd->start) + nd->start = nd->end; + } + if (nd->end > end) { + nd->end = end; + if (nd->start > nd->end) + nd->start = nd->end; + } +} + +static __init void bad_srat(void) +{ + int i; + printk(KERN_ERR "SRAT: SRAT not used.\n"); + acpi_numa = -1; + found_add_area = 0; + for (i = 0; i < MAX_LOCAL_APIC; i++) + apicid_to_node[i] = NUMA_NO_NODE; + for (i = 0; i < MAX_NUMNODES; i++) + nodes_add[i].start = nodes[i].end = 0; + remove_all_active_ranges(); +} + +static __init inline int srat_disabled(void) +{ + return numa_off || acpi_numa < 0; +} + +/* + * A lot of BIOS fill in 10 (= no distance) everywhere. This messes + * up the NUMA heuristics which wants the local node to have a smaller + * distance than the others. + * Do some quick checks here and only use the SLIT if it passes. + */ +static __init int slit_valid(struct acpi_table_slit *slit) +{ + int i, j; + int d = slit->locality_count; + for (i = 0; i < d; i++) { + for (j = 0; j < d; j++) { + u8 val = slit->entry[d*i + j]; + if (i == j) { + if (val != LOCAL_DISTANCE) + return 0; + } else if (val <= LOCAL_DISTANCE) + return 0; + } + } + return 1; +} + +/* Callback for SLIT parsing */ +void __init acpi_numa_slit_init(struct acpi_table_slit *slit) +{ + if (!slit_valid(slit)) { + printk(KERN_INFO "ACPI: SLIT table looks invalid. Not used.\n"); + return; + } + acpi_slit = slit; +} + +/* Callback for Proximity Domain -> LAPIC mapping */ +void __init +acpi_numa_processor_affinity_init(struct acpi_srat_cpu_affinity *pa) +{ + int pxm, node; + if (srat_disabled()) + return; + if (pa->header.length != sizeof(struct acpi_srat_cpu_affinity)) { + bad_srat(); + return; + } + if ((pa->flags & ACPI_SRAT_CPU_ENABLED) == 0) + return; + pxm = pa->proximity_domain_lo; + node = setup_node(pxm); + if (node < 0) { + printk(KERN_ERR "SRAT: Too many proximity domains %x\n", pxm); + bad_srat(); + return; + } + apicid_to_node[pa->apic_id] = node; + acpi_numa = 1; + printk(KERN_INFO "SRAT: PXM %u -> APIC %u -> Node %u\n", + pxm, pa->apic_id, node); +} + +#ifdef CONFIG_MEMORY_HOTPLUG_RESERVE +/* + * Protect against too large hotadd areas that would fill up memory. + */ +static int hotadd_enough_memory(struct bootnode *nd) +{ + static unsigned long allocated; + static unsigned long last_area_end; + unsigned long pages = (nd->end - nd->start) >> PAGE_SHIFT; + long mem = pages * sizeof(struct page); + unsigned long addr; + unsigned long allowed; + unsigned long oldpages = pages; + + if (mem < 0) + return 0; + allowed = (end_pfn - absent_pages_in_range(0, end_pfn)) * PAGE_SIZE; + allowed = (allowed / 100) * hotadd_percent; + if (allocated + mem > allowed) { + unsigned long range; + /* Give them at least part of their hotadd memory upto hotadd_percent + It would be better to spread the limit out + over multiple hotplug areas, but that is too complicated + right now */ + if (allocated >= allowed) + return 0; + range = allowed - allocated; + pages = (range / PAGE_SIZE); + mem = pages * sizeof(struct page); + nd->end = nd->start + range; + } + /* Not completely fool proof, but a good sanity check */ + addr = find_e820_area(last_area_end, end_pfn<<PAGE_SHIFT, mem); + if (addr == -1UL) + return 0; + if (pages != oldpages) + printk(KERN_NOTICE "SRAT: Hotadd area limited to %lu bytes\n", + pages << PAGE_SHIFT); + last_area_end = addr + mem; + allocated += mem; + return 1; +} + +static int update_end_of_memory(unsigned long end) +{ + found_add_area = 1; + if ((end >> PAGE_SHIFT) > end_pfn) + end_pfn = end >> PAGE_SHIFT; + return 1; +} + +static inline int save_add_info(void) +{ + return hotadd_percent > 0; +} +#else +int update_end_of_memory(unsigned long end) {return -1;} +static int hotadd_enough_memory(struct bootnode *nd) {return 1;} +#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE +static inline int save_add_info(void) {return 1;} +#else +static inline int save_add_info(void) {return 0;} +#endif +#endif +/* + * Update nodes_add and decide if to include add are in the zone. + * Both SPARSE and RESERVE need nodes_add infomation. + * This code supports one contigious hot add area per node. + */ +static int reserve_hotadd(int node, unsigned long start, unsigned long end) +{ + unsigned long s_pfn = start >> PAGE_SHIFT; + unsigned long e_pfn = end >> PAGE_SHIFT; + int ret = 0, changed = 0; + struct bootnode *nd = &nodes_add[node]; + + /* I had some trouble with strange memory hotadd regions breaking + the boot. Be very strict here and reject anything unexpected. + If you want working memory hotadd write correct SRATs. + + The node size check is a basic sanity check to guard against + mistakes */ + if ((signed long)(end - start) < NODE_MIN_SIZE) { + printk(KERN_ERR "SRAT: Hotplug area too small\n"); + return -1; + } + + /* This check might be a bit too strict, but I'm keeping it for now. */ + if (absent_pages_in_range(s_pfn, e_pfn) != e_pfn - s_pfn) { + printk(KERN_ERR + "SRAT: Hotplug area %lu -> %lu has existing memory\n", + s_pfn, e_pfn); + return -1; + } + + if (!hotadd_enough_memory(&nodes_add[node])) { + printk(KERN_ERR "SRAT: Hotplug area too large\n"); + return -1; + } + + /* Looks good */ + + if (nd->start == nd->end) { + nd->start = start; + nd->end = end; + changed = 1; + } else { + if (nd->start == end) { + nd->start = start; + changed = 1; + } + if (nd->end == start) { + nd->end = end; + changed = 1; + } + if (!changed) + printk(KERN_ERR "SRAT: Hotplug zone not continuous. Partly ignored\n"); + } + + ret = update_end_of_memory(nd->end); + + if (changed) + printk(KERN_INFO "SRAT: hot plug zone found %Lx - %Lx\n", nd->start, nd->end); + return ret; +} + +/* Callback for parsing of the Proximity Domain <-> Memory Area mappings */ +void __init +acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma) +{ + struct bootnode *nd, oldnode; + unsigned long start, end; + int node, pxm; + int i; + + if (srat_disabled()) + return; + if (ma->header.length != sizeof(struct acpi_srat_mem_affinity)) { + bad_srat(); + return; + } + if ((ma->flags & ACPI_SRAT_MEM_ENABLED) == 0) + return; + + if ((ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) && !save_add_info()) + return; + start = ma->base_address; + end = start + ma->length; + pxm = ma->proximity_domain; + node = setup_node(pxm); + if (node < 0) { + printk(KERN_ERR "SRAT: Too many proximity domains.\n"); + bad_srat(); + return; + } + i = conflicting_nodes(start, end); + if (i == node) { + printk(KERN_WARNING + "SRAT: Warning: PXM %d (%lx-%lx) overlaps with itself (%Lx-%Lx)\n", + pxm, start, end, nodes[i].start, nodes[i].end); + } else if (i >= 0) { + printk(KERN_ERR + "SRAT: PXM %d (%lx-%lx) overlaps with PXM %d (%Lx-%Lx)\n", + pxm, start, end, node_to_pxm(i), + nodes[i].start, nodes[i].end); + bad_srat(); + return; + } + nd = &nodes[node]; + oldnode = *nd; + if (!node_test_and_set(node, nodes_parsed)) { + nd->start = start; + nd->end = end; + } else { + if (start < nd->start) + nd->start = start; + if (nd->end < end) + nd->end = end; + } + + printk(KERN_INFO "SRAT: Node %u PXM %u %Lx-%Lx\n", node, pxm, + nd->start, nd->end); + e820_register_active_regions(node, nd->start >> PAGE_SHIFT, + nd->end >> PAGE_SHIFT); + push_node_boundaries(node, nd->start >> PAGE_SHIFT, + nd->end >> PAGE_SHIFT); + + if ((ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) && + (reserve_hotadd(node, start, end) < 0)) { + /* Ignore hotadd region. Undo damage */ + printk(KERN_NOTICE "SRAT: Hotplug region ignored\n"); + *nd = oldnode; + if ((nd->start | nd->end) == 0) + node_clear(node, nodes_parsed); + } +} + +/* Sanity check to catch more bad SRATs (they are amazingly common). + Make sure the PXMs cover all memory. */ +static int __init nodes_cover_memory(const struct bootnode *nodes) +{ + int i; + unsigned long pxmram, e820ram; + + pxmram = 0; + for_each_node_mask(i, nodes_parsed) { + unsigned long s = nodes[i].start >> PAGE_SHIFT; + unsigned long e = nodes[i].end >> PAGE_SHIFT; + pxmram += e - s; + pxmram -= absent_pages_in_range(s, e); + if ((long)pxmram < 0) + pxmram = 0; + } + + e820ram = end_pfn - absent_pages_in_range(0, end_pfn); + /* We seem to lose 3 pages somewhere. Allow a bit of slack. */ + if ((long)(e820ram - pxmram) >= 1*1024*1024) { + printk(KERN_ERR + "SRAT: PXMs only cover %luMB of your %luMB e820 RAM. Not used.\n", + (pxmram << PAGE_SHIFT) >> 20, + (e820ram << PAGE_SHIFT) >> 20); + return 0; + } + return 1; +} + +static void unparse_node(int node) +{ + int i; + node_clear(node, nodes_parsed); + for (i = 0; i < MAX_LOCAL_APIC; i++) { + if (apicid_to_node[i] == node) + apicid_to_node[i] = NUMA_NO_NODE; + } +} + +void __init acpi_numa_arch_fixup(void) {} + +/* Use the information discovered above to actually set up the nodes. */ +int __init acpi_scan_nodes(unsigned long start, unsigned long end) +{ + int i; + + if (acpi_numa <= 0) + return -1; + + /* First clean up the node list */ + for (i = 0; i < MAX_NUMNODES; i++) { + cutoff_node(i, start, end); + if ((nodes[i].end - nodes[i].start) < NODE_MIN_SIZE) { + unparse_node(i); + node_set_offline(i); + } + } + + if (!nodes_cover_memory(nodes)) { + bad_srat(); + return -1; + } + + memnode_shift = compute_hash_shift(nodes, MAX_NUMNODES); + if (memnode_shift < 0) { + printk(KERN_ERR + "SRAT: No NUMA node hash function found. Contact maintainer\n"); + bad_srat(); + return -1; + } + + node_possible_map = nodes_parsed; + + /* Finally register nodes */ + for_each_node_mask(i, node_possible_map) + setup_node_bootmem(i, nodes[i].start, nodes[i].end); + /* Try again in case setup_node_bootmem missed one due + to missing bootmem */ + for_each_node_mask(i, node_possible_map) + if (!node_online(i)) + setup_node_bootmem(i, nodes[i].start, nodes[i].end); + + for (i = 0; i < NR_CPUS; i++) { + if (cpu_to_node[i] == NUMA_NO_NODE) + continue; + if (!node_isset(cpu_to_node[i], node_possible_map)) + numa_set_node(i, NUMA_NO_NODE); + } + numa_init_array(); + return 0; +} + +#ifdef CONFIG_NUMA_EMU +static int __init find_node_by_addr(unsigned long addr) +{ + int ret = NUMA_NO_NODE; + int i; + + for_each_node_mask(i, nodes_parsed) { + /* + * Find the real node that this emulated node appears on. For + * the sake of simplicity, we only use a real node's starting + * address to determine which emulated node it appears on. + */ + if (addr >= nodes[i].start && addr < nodes[i].end) { + ret = i; + break; + } + } + return i; +} + +/* + * In NUMA emulation, we need to setup proximity domain (_PXM) to node ID + * mappings that respect the real ACPI topology but reflect our emulated + * environment. For each emulated node, we find which real node it appears on + * and create PXM to NID mappings for those fake nodes which mirror that + * locality. SLIT will now represent the correct distances between emulated + * nodes as a result of the real topology. + */ +void __init acpi_fake_nodes(const struct bootnode *fake_nodes, int num_nodes) +{ + int i, j; + int fake_node_to_pxm_map[MAX_NUMNODES] = { + [0 ... MAX_NUMNODES-1] = PXM_INVAL + }; + unsigned char fake_apicid_to_node[MAX_LOCAL_APIC] = { + [0 ... MAX_LOCAL_APIC-1] = NUMA_NO_NODE + }; + + printk(KERN_INFO "Faking PXM affinity for fake nodes on real " + "topology.\n"); + for (i = 0; i < num_nodes; i++) { + int nid, pxm; + + nid = find_node_by_addr(fake_nodes[i].start); + if (nid == NUMA_NO_NODE) + continue; + pxm = node_to_pxm(nid); + if (pxm == PXM_INVAL) + continue; + fake_node_to_pxm_map[i] = pxm; + /* + * For each apicid_to_node mapping that exists for this real + * node, it must now point to the fake node ID. + */ + for (j = 0; j < MAX_LOCAL_APIC; j++) + if (apicid_to_node[j] == nid) + fake_apicid_to_node[j] = i; + } + for (i = 0; i < num_nodes; i++) + __acpi_map_pxm_to_node(fake_node_to_pxm_map[i], i); + memcpy(apicid_to_node, fake_apicid_to_node, sizeof(apicid_to_node)); + + nodes_clear(nodes_parsed); + for (i = 0; i < num_nodes; i++) + if (fake_nodes[i].start != fake_nodes[i].end) + node_set(i, nodes_parsed); + WARN_ON(!nodes_cover_memory(fake_nodes)); +} + +static int null_slit_node_compare(int a, int b) +{ + return node_to_pxm(a) == node_to_pxm(b); +} +#else +static int null_slit_node_compare(int a, int b) +{ + return a == b; +} +#endif /* CONFIG_NUMA_EMU */ + +void __init srat_reserve_add_area(int nodeid) +{ + if (found_add_area && nodes_add[nodeid].end) { + u64 total_mb; + + printk(KERN_INFO "SRAT: Reserving hot-add memory space " + "for node %d at %Lx-%Lx\n", + nodeid, nodes_add[nodeid].start, nodes_add[nodeid].end); + total_mb = (nodes_add[nodeid].end - nodes_add[nodeid].start) + >> PAGE_SHIFT; + total_mb *= sizeof(struct page); + total_mb >>= 20; + printk(KERN_INFO "SRAT: This will cost you %Lu MB of " + "pre-allocated memory.\n", (unsigned long long)total_mb); + reserve_bootmem_node(NODE_DATA(nodeid), nodes_add[nodeid].start, + nodes_add[nodeid].end - nodes_add[nodeid].start); + } +} + +int __node_distance(int a, int b) +{ + int index; + + if (!acpi_slit) + return null_slit_node_compare(a, b) ? LOCAL_DISTANCE : + REMOTE_DISTANCE; + index = acpi_slit->locality_count * node_to_pxm(a); + return acpi_slit->entry[index + node_to_pxm(b)]; +} + +EXPORT_SYMBOL(__node_distance); + +int memory_add_physaddr_to_nid(u64 start) +{ + int i, ret = 0; + + for_each_node(i) + if (nodes_add[i].start <= start && nodes_add[i].end > start) + ret = i; + + return ret; +} +EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); + |