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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/x86/mm/numa.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/mm/numa.c')
-rw-r--r--arch/x86/mm/numa.c1037
1 files changed, 1037 insertions, 0 deletions
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
new file mode 100644
index 0000000000..aa39d678fe
--- /dev/null
+++ b/arch/x86/mm/numa.c
@@ -0,0 +1,1037 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Common code for 32 and 64-bit NUMA */
+#include <linux/acpi.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/memblock.h>
+#include <linux/mmzone.h>
+#include <linux/ctype.h>
+#include <linux/nodemask.h>
+#include <linux/sched.h>
+#include <linux/topology.h>
+#include <linux/sort.h>
+
+#include <asm/e820/api.h>
+#include <asm/proto.h>
+#include <asm/dma.h>
+#include <asm/amd_nb.h>
+
+#include "numa_internal.h"
+
+int numa_off;
+nodemask_t numa_nodes_parsed __initdata;
+
+struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
+EXPORT_SYMBOL(node_data);
+
+static struct numa_meminfo numa_meminfo __initdata_or_meminfo;
+static struct numa_meminfo numa_reserved_meminfo __initdata_or_meminfo;
+
+static int numa_distance_cnt;
+static u8 *numa_distance;
+
+static __init int numa_setup(char *opt)
+{
+ if (!opt)
+ return -EINVAL;
+ if (!strncmp(opt, "off", 3))
+ numa_off = 1;
+ if (!strncmp(opt, "fake=", 5))
+ return numa_emu_cmdline(opt + 5);
+ if (!strncmp(opt, "noacpi", 6))
+ disable_srat();
+ if (!strncmp(opt, "nohmat", 6))
+ disable_hmat();
+ return 0;
+}
+early_param("numa", numa_setup);
+
+/*
+ * apicid, cpu, node mappings
+ */
+s16 __apicid_to_node[MAX_LOCAL_APIC] = {
+ [0 ... MAX_LOCAL_APIC-1] = NUMA_NO_NODE
+};
+
+int numa_cpu_node(int cpu)
+{
+ int apicid = early_per_cpu(x86_cpu_to_apicid, cpu);
+
+ if (apicid != BAD_APICID)
+ return __apicid_to_node[apicid];
+ return NUMA_NO_NODE;
+}
+
+cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
+EXPORT_SYMBOL(node_to_cpumask_map);
+
+/*
+ * Map cpu index to node index
+ */
+DEFINE_EARLY_PER_CPU(int, x86_cpu_to_node_map, NUMA_NO_NODE);
+EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_node_map);
+
+void numa_set_node(int cpu, int node)
+{
+ int *cpu_to_node_map = early_per_cpu_ptr(x86_cpu_to_node_map);
+
+ /* early setting, no percpu area yet */
+ if (cpu_to_node_map) {
+ cpu_to_node_map[cpu] = node;
+ return;
+ }
+
+#ifdef CONFIG_DEBUG_PER_CPU_MAPS
+ if (cpu >= nr_cpu_ids || !cpu_possible(cpu)) {
+ printk(KERN_ERR "numa_set_node: invalid cpu# (%d)\n", cpu);
+ dump_stack();
+ return;
+ }
+#endif
+ per_cpu(x86_cpu_to_node_map, cpu) = node;
+
+ set_cpu_numa_node(cpu, node);
+}
+
+void numa_clear_node(int cpu)
+{
+ numa_set_node(cpu, NUMA_NO_NODE);
+}
+
+/*
+ * 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.
+ * (Use CONFIG_DEBUG_PER_CPU_MAPS to check this.)
+ */
+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 */
+ pr_debug("Node to cpumask map for %u nodes\n", nr_node_ids);
+}
+
+static int __init numa_add_memblk_to(int nid, u64 start, u64 end,
+ struct numa_meminfo *mi)
+{
+ /* ignore zero length blks */
+ if (start == end)
+ return 0;
+
+ /* whine about and ignore invalid blks */
+ if (start > end || nid < 0 || nid >= MAX_NUMNODES) {
+ pr_warn("Warning: invalid memblk node %d [mem %#010Lx-%#010Lx]\n",
+ nid, start, end - 1);
+ return 0;
+ }
+
+ if (mi->nr_blks >= NR_NODE_MEMBLKS) {
+ pr_err("too many memblk ranges\n");
+ return -EINVAL;
+ }
+
+ mi->blk[mi->nr_blks].start = start;
+ mi->blk[mi->nr_blks].end = end;
+ mi->blk[mi->nr_blks].nid = nid;
+ mi->nr_blks++;
+ return 0;
+}
+
+/**
+ * numa_remove_memblk_from - Remove one numa_memblk from a numa_meminfo
+ * @idx: Index of memblk to remove
+ * @mi: numa_meminfo to remove memblk from
+ *
+ * Remove @idx'th numa_memblk from @mi by shifting @mi->blk[] and
+ * decrementing @mi->nr_blks.
+ */
+void __init numa_remove_memblk_from(int idx, struct numa_meminfo *mi)
+{
+ mi->nr_blks--;
+ memmove(&mi->blk[idx], &mi->blk[idx + 1],
+ (mi->nr_blks - idx) * sizeof(mi->blk[0]));
+}
+
+/**
+ * numa_move_tail_memblk - Move a numa_memblk from one numa_meminfo to another
+ * @dst: numa_meminfo to append block to
+ * @idx: Index of memblk to remove
+ * @src: numa_meminfo to remove memblk from
+ */
+static void __init numa_move_tail_memblk(struct numa_meminfo *dst, int idx,
+ struct numa_meminfo *src)
+{
+ dst->blk[dst->nr_blks++] = src->blk[idx];
+ numa_remove_memblk_from(idx, src);
+}
+
+/**
+ * numa_add_memblk - Add one numa_memblk to numa_meminfo
+ * @nid: NUMA node ID of the new memblk
+ * @start: Start address of the new memblk
+ * @end: End address of the new memblk
+ *
+ * Add a new memblk to the default numa_meminfo.
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+int __init numa_add_memblk(int nid, u64 start, u64 end)
+{
+ return numa_add_memblk_to(nid, start, end, &numa_meminfo);
+}
+
+/* Allocate NODE_DATA for a node on the local memory */
+static void __init alloc_node_data(int nid)
+{
+ const size_t nd_size = roundup(sizeof(pg_data_t), PAGE_SIZE);
+ u64 nd_pa;
+ void *nd;
+ int tnid;
+
+ /*
+ * Allocate node data. Try node-local memory and then any node.
+ * Never allocate in DMA zone.
+ */
+ nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
+ if (!nd_pa) {
+ pr_err("Cannot find %zu bytes in any node (initial node: %d)\n",
+ nd_size, nid);
+ return;
+ }
+ nd = __va(nd_pa);
+
+ /* report and initialize */
+ printk(KERN_INFO "NODE_DATA(%d) allocated [mem %#010Lx-%#010Lx]\n", nid,
+ nd_pa, nd_pa + nd_size - 1);
+ tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT);
+ if (tnid != nid)
+ printk(KERN_INFO " NODE_DATA(%d) on node %d\n", nid, tnid);
+
+ node_data[nid] = nd;
+ memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
+
+ node_set_online(nid);
+}
+
+/**
+ * numa_cleanup_meminfo - Cleanup a numa_meminfo
+ * @mi: numa_meminfo to clean up
+ *
+ * Sanitize @mi by merging and removing unnecessary memblks. Also check for
+ * conflicts and clear unused memblks.
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+int __init numa_cleanup_meminfo(struct numa_meminfo *mi)
+{
+ const u64 low = 0;
+ const u64 high = PFN_PHYS(max_pfn);
+ int i, j, k;
+
+ /* first, trim all entries */
+ for (i = 0; i < mi->nr_blks; i++) {
+ struct numa_memblk *bi = &mi->blk[i];
+
+ /* move / save reserved memory ranges */
+ if (!memblock_overlaps_region(&memblock.memory,
+ bi->start, bi->end - bi->start)) {
+ numa_move_tail_memblk(&numa_reserved_meminfo, i--, mi);
+ continue;
+ }
+
+ /* make sure all non-reserved blocks are inside the limits */
+ bi->start = max(bi->start, low);
+
+ /* preserve info for non-RAM areas above 'max_pfn': */
+ if (bi->end > high) {
+ numa_add_memblk_to(bi->nid, high, bi->end,
+ &numa_reserved_meminfo);
+ bi->end = high;
+ }
+
+ /* and there's no empty block */
+ if (bi->start >= bi->end)
+ numa_remove_memblk_from(i--, mi);
+ }
+
+ /* merge neighboring / overlapping entries */
+ for (i = 0; i < mi->nr_blks; i++) {
+ struct numa_memblk *bi = &mi->blk[i];
+
+ for (j = i + 1; j < mi->nr_blks; j++) {
+ struct numa_memblk *bj = &mi->blk[j];
+ u64 start, end;
+
+ /*
+ * See whether there are overlapping blocks. Whine
+ * about but allow overlaps of the same nid. They
+ * will be merged below.
+ */
+ if (bi->end > bj->start && bi->start < bj->end) {
+ if (bi->nid != bj->nid) {
+ pr_err("node %d [mem %#010Lx-%#010Lx] overlaps with node %d [mem %#010Lx-%#010Lx]\n",
+ bi->nid, bi->start, bi->end - 1,
+ bj->nid, bj->start, bj->end - 1);
+ return -EINVAL;
+ }
+ pr_warn("Warning: node %d [mem %#010Lx-%#010Lx] overlaps with itself [mem %#010Lx-%#010Lx]\n",
+ bi->nid, bi->start, bi->end - 1,
+ bj->start, bj->end - 1);
+ }
+
+ /*
+ * Join together blocks on the same node, holes
+ * between which don't overlap with memory on other
+ * nodes.
+ */
+ if (bi->nid != bj->nid)
+ continue;
+ start = min(bi->start, bj->start);
+ end = max(bi->end, bj->end);
+ for (k = 0; k < mi->nr_blks; k++) {
+ struct numa_memblk *bk = &mi->blk[k];
+
+ if (bi->nid == bk->nid)
+ continue;
+ if (start < bk->end && end > bk->start)
+ break;
+ }
+ if (k < mi->nr_blks)
+ continue;
+ printk(KERN_INFO "NUMA: Node %d [mem %#010Lx-%#010Lx] + [mem %#010Lx-%#010Lx] -> [mem %#010Lx-%#010Lx]\n",
+ bi->nid, bi->start, bi->end - 1, bj->start,
+ bj->end - 1, start, end - 1);
+ bi->start = start;
+ bi->end = end;
+ numa_remove_memblk_from(j--, mi);
+ }
+ }
+
+ /* clear unused ones */
+ for (i = mi->nr_blks; i < ARRAY_SIZE(mi->blk); i++) {
+ mi->blk[i].start = mi->blk[i].end = 0;
+ mi->blk[i].nid = NUMA_NO_NODE;
+ }
+
+ return 0;
+}
+
+/*
+ * Set nodes, which have memory in @mi, in *@nodemask.
+ */
+static void __init numa_nodemask_from_meminfo(nodemask_t *nodemask,
+ const struct numa_meminfo *mi)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(mi->blk); i++)
+ if (mi->blk[i].start != mi->blk[i].end &&
+ mi->blk[i].nid != NUMA_NO_NODE)
+ node_set(mi->blk[i].nid, *nodemask);
+}
+
+/**
+ * numa_reset_distance - Reset NUMA distance table
+ *
+ * The current table is freed. The next numa_set_distance() call will
+ * create a new one.
+ */
+void __init numa_reset_distance(void)
+{
+ size_t size = numa_distance_cnt * numa_distance_cnt * sizeof(numa_distance[0]);
+
+ /* numa_distance could be 1LU marking allocation failure, test cnt */
+ if (numa_distance_cnt)
+ memblock_free(numa_distance, size);
+ numa_distance_cnt = 0;
+ numa_distance = NULL; /* enable table creation */
+}
+
+static int __init numa_alloc_distance(void)
+{
+ nodemask_t nodes_parsed;
+ size_t size;
+ int i, j, cnt = 0;
+ u64 phys;
+
+ /* size the new table and allocate it */
+ nodes_parsed = numa_nodes_parsed;
+ numa_nodemask_from_meminfo(&nodes_parsed, &numa_meminfo);
+
+ for_each_node_mask(i, nodes_parsed)
+ cnt = i;
+ cnt++;
+ size = cnt * cnt * sizeof(numa_distance[0]);
+
+ phys = memblock_phys_alloc_range(size, PAGE_SIZE, 0,
+ PFN_PHYS(max_pfn_mapped));
+ if (!phys) {
+ pr_warn("Warning: can't allocate distance table!\n");
+ /* don't retry until explicitly reset */
+ numa_distance = (void *)1LU;
+ return -ENOMEM;
+ }
+
+ numa_distance = __va(phys);
+ numa_distance_cnt = cnt;
+
+ /* fill with the default distances */
+ for (i = 0; i < cnt; i++)
+ for (j = 0; j < cnt; j++)
+ numa_distance[i * cnt + j] = i == j ?
+ LOCAL_DISTANCE : REMOTE_DISTANCE;
+ printk(KERN_DEBUG "NUMA: Initialized distance table, cnt=%d\n", cnt);
+
+ return 0;
+}
+
+/**
+ * numa_set_distance - Set NUMA distance from one NUMA to another
+ * @from: the 'from' node to set distance
+ * @to: the 'to' node to set distance
+ * @distance: NUMA distance
+ *
+ * Set the distance from node @from to @to to @distance. If distance table
+ * doesn't exist, one which is large enough to accommodate all the currently
+ * known nodes will be created.
+ *
+ * If such table cannot be allocated, a warning is printed and further
+ * calls are ignored until the distance table is reset with
+ * numa_reset_distance().
+ *
+ * If @from or @to is higher than the highest known node or lower than zero
+ * at the time of table creation or @distance doesn't make sense, the call
+ * is ignored.
+ * This is to allow simplification of specific NUMA config implementations.
+ */
+void __init numa_set_distance(int from, int to, int distance)
+{
+ if (!numa_distance && numa_alloc_distance() < 0)
+ return;
+
+ if (from >= numa_distance_cnt || to >= numa_distance_cnt ||
+ from < 0 || to < 0) {
+ pr_warn_once("Warning: node ids are out of bound, from=%d to=%d distance=%d\n",
+ from, to, distance);
+ return;
+ }
+
+ if ((u8)distance != distance ||
+ (from == to && distance != LOCAL_DISTANCE)) {
+ pr_warn_once("Warning: invalid distance parameter, from=%d to=%d distance=%d\n",
+ from, to, distance);
+ return;
+ }
+
+ numa_distance[from * numa_distance_cnt + to] = distance;
+}
+
+int __node_distance(int from, int to)
+{
+ if (from >= numa_distance_cnt || to >= numa_distance_cnt)
+ return from == to ? LOCAL_DISTANCE : REMOTE_DISTANCE;
+ return numa_distance[from * numa_distance_cnt + to];
+}
+EXPORT_SYMBOL(__node_distance);
+
+/*
+ * Sanity check to catch more bad NUMA configurations (they are amazingly
+ * common). Make sure the nodes cover all memory.
+ */
+static bool __init numa_meminfo_cover_memory(const struct numa_meminfo *mi)
+{
+ u64 numaram, e820ram;
+ int i;
+
+ numaram = 0;
+ for (i = 0; i < mi->nr_blks; i++) {
+ u64 s = mi->blk[i].start >> PAGE_SHIFT;
+ u64 e = mi->blk[i].end >> PAGE_SHIFT;
+ numaram += e - s;
+ numaram -= __absent_pages_in_range(mi->blk[i].nid, s, e);
+ if ((s64)numaram < 0)
+ numaram = 0;
+ }
+
+ e820ram = max_pfn - absent_pages_in_range(0, max_pfn);
+
+ /* We seem to lose 3 pages somewhere. Allow 1M of slack. */
+ if ((s64)(e820ram - numaram) >= (1 << (20 - PAGE_SHIFT))) {
+ printk(KERN_ERR "NUMA: nodes only cover %LuMB of your %LuMB e820 RAM. Not used.\n",
+ (numaram << PAGE_SHIFT) >> 20,
+ (e820ram << PAGE_SHIFT) >> 20);
+ return false;
+ }
+ return true;
+}
+
+/*
+ * Mark all currently memblock-reserved physical memory (which covers the
+ * kernel's own memory ranges) as hot-unswappable.
+ */
+static void __init numa_clear_kernel_node_hotplug(void)
+{
+ nodemask_t reserved_nodemask = NODE_MASK_NONE;
+ struct memblock_region *mb_region;
+ int i;
+
+ /*
+ * We have to do some preprocessing of memblock regions, to
+ * make them suitable for reservation.
+ *
+ * At this time, all memory regions reserved by memblock are
+ * used by the kernel, but those regions are not split up
+ * along node boundaries yet, and don't necessarily have their
+ * node ID set yet either.
+ *
+ * So iterate over all memory known to the x86 architecture,
+ * and use those ranges to set the nid in memblock.reserved.
+ * This will split up the memblock regions along node
+ * boundaries and will set the node IDs as well.
+ */
+ for (i = 0; i < numa_meminfo.nr_blks; i++) {
+ struct numa_memblk *mb = numa_meminfo.blk + i;
+ int ret;
+
+ ret = memblock_set_node(mb->start, mb->end - mb->start, &memblock.reserved, mb->nid);
+ WARN_ON_ONCE(ret);
+ }
+
+ /*
+ * Now go over all reserved memblock regions, to construct a
+ * node mask of all kernel reserved memory areas.
+ *
+ * [ Note, when booting with mem=nn[kMG] or in a kdump kernel,
+ * numa_meminfo might not include all memblock.reserved
+ * memory ranges, because quirks such as trim_snb_memory()
+ * reserve specific pages for Sandy Bridge graphics. ]
+ */
+ for_each_reserved_mem_region(mb_region) {
+ int nid = memblock_get_region_node(mb_region);
+
+ if (nid != MAX_NUMNODES)
+ node_set(nid, reserved_nodemask);
+ }
+
+ /*
+ * Finally, clear the MEMBLOCK_HOTPLUG flag for all memory
+ * belonging to the reserved node mask.
+ *
+ * Note that this will include memory regions that reside
+ * on nodes that contain kernel memory - entire nodes
+ * become hot-unpluggable:
+ */
+ for (i = 0; i < numa_meminfo.nr_blks; i++) {
+ struct numa_memblk *mb = numa_meminfo.blk + i;
+
+ if (!node_isset(mb->nid, reserved_nodemask))
+ continue;
+
+ memblock_clear_hotplug(mb->start, mb->end - mb->start);
+ }
+}
+
+static int __init numa_register_memblks(struct numa_meminfo *mi)
+{
+ int i, nid;
+
+ /* Account for nodes with cpus and no memory */
+ node_possible_map = numa_nodes_parsed;
+ numa_nodemask_from_meminfo(&node_possible_map, mi);
+ if (WARN_ON(nodes_empty(node_possible_map)))
+ return -EINVAL;
+
+ for (i = 0; i < mi->nr_blks; i++) {
+ struct numa_memblk *mb = &mi->blk[i];
+ memblock_set_node(mb->start, mb->end - mb->start,
+ &memblock.memory, mb->nid);
+ }
+
+ /*
+ * At very early time, the kernel have to use some memory such as
+ * loading the kernel image. We cannot prevent this anyway. So any
+ * node the kernel resides in should be un-hotpluggable.
+ *
+ * And when we come here, alloc node data won't fail.
+ */
+ numa_clear_kernel_node_hotplug();
+
+ /*
+ * If sections array is gonna be used for pfn -> nid mapping, check
+ * whether its granularity is fine enough.
+ */
+ if (IS_ENABLED(NODE_NOT_IN_PAGE_FLAGS)) {
+ unsigned long pfn_align = node_map_pfn_alignment();
+
+ if (pfn_align && pfn_align < PAGES_PER_SECTION) {
+ pr_warn("Node alignment %LuMB < min %LuMB, rejecting NUMA config\n",
+ PFN_PHYS(pfn_align) >> 20,
+ PFN_PHYS(PAGES_PER_SECTION) >> 20);
+ return -EINVAL;
+ }
+ }
+ if (!numa_meminfo_cover_memory(mi))
+ return -EINVAL;
+
+ /* Finally register nodes. */
+ for_each_node_mask(nid, node_possible_map) {
+ u64 start = PFN_PHYS(max_pfn);
+ u64 end = 0;
+
+ for (i = 0; i < mi->nr_blks; i++) {
+ if (nid != mi->blk[i].nid)
+ continue;
+ start = min(mi->blk[i].start, start);
+ end = max(mi->blk[i].end, end);
+ }
+
+ if (start >= end)
+ continue;
+
+ alloc_node_data(nid);
+ }
+
+ /* Dump memblock with node info and return. */
+ memblock_dump_all();
+ return 0;
+}
+
+/*
+ * There are unfortunately some poorly designed mainboards around that
+ * only connect memory to a single CPU. This breaks the 1:1 cpu->node
+ * mapping. To avoid this fill in the mapping for all possible CPUs,
+ * as the number of CPUs is not known yet. We round robin the existing
+ * nodes.
+ */
+static void __init numa_init_array(void)
+{
+ int rr, i;
+
+ rr = first_node(node_online_map);
+ for (i = 0; i < nr_cpu_ids; i++) {
+ if (early_cpu_to_node(i) != NUMA_NO_NODE)
+ continue;
+ numa_set_node(i, rr);
+ rr = next_node_in(rr, node_online_map);
+ }
+}
+
+static int __init numa_init(int (*init_func)(void))
+{
+ int i;
+ int ret;
+
+ for (i = 0; i < MAX_LOCAL_APIC; i++)
+ set_apicid_to_node(i, NUMA_NO_NODE);
+
+ nodes_clear(numa_nodes_parsed);
+ nodes_clear(node_possible_map);
+ nodes_clear(node_online_map);
+ memset(&numa_meminfo, 0, sizeof(numa_meminfo));
+ WARN_ON(memblock_set_node(0, ULLONG_MAX, &memblock.memory,
+ MAX_NUMNODES));
+ WARN_ON(memblock_set_node(0, ULLONG_MAX, &memblock.reserved,
+ MAX_NUMNODES));
+ /* In case that parsing SRAT failed. */
+ WARN_ON(memblock_clear_hotplug(0, ULLONG_MAX));
+ numa_reset_distance();
+
+ ret = init_func();
+ if (ret < 0)
+ return ret;
+
+ /*
+ * We reset memblock back to the top-down direction
+ * here because if we configured ACPI_NUMA, we have
+ * parsed SRAT in init_func(). It is ok to have the
+ * reset here even if we did't configure ACPI_NUMA
+ * or acpi numa init fails and fallbacks to dummy
+ * numa init.
+ */
+ memblock_set_bottom_up(false);
+
+ ret = numa_cleanup_meminfo(&numa_meminfo);
+ if (ret < 0)
+ return ret;
+
+ numa_emulation(&numa_meminfo, numa_distance_cnt);
+
+ ret = numa_register_memblks(&numa_meminfo);
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < nr_cpu_ids; i++) {
+ int nid = early_cpu_to_node(i);
+
+ if (nid == NUMA_NO_NODE)
+ continue;
+ if (!node_online(nid))
+ numa_clear_node(i);
+ }
+ numa_init_array();
+
+ return 0;
+}
+
+/**
+ * dummy_numa_init - Fallback dummy NUMA init
+ *
+ * Used if there's no underlying NUMA architecture, NUMA initialization
+ * fails, or NUMA is disabled on the command line.
+ *
+ * Must online at least one node and add memory blocks that cover all
+ * allowed memory. This function must not fail.
+ */
+static int __init dummy_numa_init(void)
+{
+ printk(KERN_INFO "%s\n",
+ numa_off ? "NUMA turned off" : "No NUMA configuration found");
+ printk(KERN_INFO "Faking a node at [mem %#018Lx-%#018Lx]\n",
+ 0LLU, PFN_PHYS(max_pfn) - 1);
+
+ node_set(0, numa_nodes_parsed);
+ numa_add_memblk(0, 0, PFN_PHYS(max_pfn));
+
+ return 0;
+}
+
+/**
+ * x86_numa_init - Initialize NUMA
+ *
+ * Try each configured NUMA initialization method until one succeeds. The
+ * last fallback is dummy single node config encompassing whole memory and
+ * never fails.
+ */
+void __init x86_numa_init(void)
+{
+ if (!numa_off) {
+#ifdef CONFIG_ACPI_NUMA
+ if (!numa_init(x86_acpi_numa_init))
+ return;
+#endif
+#ifdef CONFIG_AMD_NUMA
+ if (!numa_init(amd_numa_init))
+ return;
+#endif
+ }
+
+ numa_init(dummy_numa_init);
+}
+
+
+/*
+ * A node may exist which has one or more Generic Initiators but no CPUs and no
+ * memory.
+ *
+ * This function must be called after init_cpu_to_node(), to ensure that any
+ * memoryless CPU nodes have already been brought online, and before the
+ * node_data[nid] is needed for zone list setup in build_all_zonelists().
+ *
+ * When this function is called, any nodes containing either memory and/or CPUs
+ * will already be online and there is no need to do anything extra, even if
+ * they also contain one or more Generic Initiators.
+ */
+void __init init_gi_nodes(void)
+{
+ int nid;
+
+ /*
+ * Exclude this node from
+ * bringup_nonboot_cpus
+ * cpu_up
+ * __try_online_node
+ * register_one_node
+ * because node_subsys is not initialized yet.
+ * TODO remove dependency on node_online
+ */
+ for_each_node_state(nid, N_GENERIC_INITIATOR)
+ if (!node_online(nid))
+ node_set_online(nid);
+}
+
+/*
+ * Setup early cpu_to_node.
+ *
+ * Populate cpu_to_node[] only if x86_cpu_to_apicid[],
+ * and apicid_to_node[] tables have valid entries for a CPU.
+ * This means we skip cpu_to_node[] initialisation for NUMA
+ * emulation and faking node case (when running a kernel compiled
+ * for NUMA on a non NUMA box), which is OK as cpu_to_node[]
+ * is already initialized in a round robin manner at numa_init_array,
+ * prior to this call, and this initialization is good enough
+ * for the fake NUMA cases.
+ *
+ * Called before the per_cpu areas are setup.
+ */
+void __init init_cpu_to_node(void)
+{
+ int cpu;
+ u16 *cpu_to_apicid = early_per_cpu_ptr(x86_cpu_to_apicid);
+
+ BUG_ON(cpu_to_apicid == NULL);
+
+ for_each_possible_cpu(cpu) {
+ int node = numa_cpu_node(cpu);
+
+ if (node == NUMA_NO_NODE)
+ continue;
+
+ /*
+ * Exclude this node from
+ * bringup_nonboot_cpus
+ * cpu_up
+ * __try_online_node
+ * register_one_node
+ * because node_subsys is not initialized yet.
+ * TODO remove dependency on node_online
+ */
+ if (!node_online(node))
+ node_set_online(node);
+
+ numa_set_node(cpu, node);
+ }
+}
+
+#ifndef CONFIG_DEBUG_PER_CPU_MAPS
+
+# ifndef CONFIG_NUMA_EMU
+void numa_add_cpu(int cpu)
+{
+ cpumask_set_cpu(cpu, node_to_cpumask_map[early_cpu_to_node(cpu)]);
+}
+
+void numa_remove_cpu(int cpu)
+{
+ cpumask_clear_cpu(cpu, node_to_cpumask_map[early_cpu_to_node(cpu)]);
+}
+# endif /* !CONFIG_NUMA_EMU */
+
+#else /* !CONFIG_DEBUG_PER_CPU_MAPS */
+
+int __cpu_to_node(int cpu)
+{
+ if (early_per_cpu_ptr(x86_cpu_to_node_map)) {
+ printk(KERN_WARNING
+ "cpu_to_node(%d): usage too early!\n", cpu);
+ dump_stack();
+ return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
+ }
+ return per_cpu(x86_cpu_to_node_map, cpu);
+}
+EXPORT_SYMBOL(__cpu_to_node);
+
+/*
+ * Same function as cpu_to_node() but used if called before the
+ * per_cpu areas are setup.
+ */
+int early_cpu_to_node(int cpu)
+{
+ if (early_per_cpu_ptr(x86_cpu_to_node_map))
+ return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
+
+ if (!cpu_possible(cpu)) {
+ printk(KERN_WARNING
+ "early_cpu_to_node(%d): no per_cpu area!\n", cpu);
+ dump_stack();
+ return NUMA_NO_NODE;
+ }
+ return per_cpu(x86_cpu_to_node_map, cpu);
+}
+
+void debug_cpumask_set_cpu(int cpu, int node, bool enable)
+{
+ struct cpumask *mask;
+
+ if (node == NUMA_NO_NODE) {
+ /* early_cpu_to_node() already emits a warning and trace */
+ return;
+ }
+ mask = node_to_cpumask_map[node];
+ if (!cpumask_available(mask)) {
+ pr_err("node_to_cpumask_map[%i] NULL\n", node);
+ dump_stack();
+ return;
+ }
+
+ if (enable)
+ cpumask_set_cpu(cpu, mask);
+ else
+ cpumask_clear_cpu(cpu, mask);
+
+ printk(KERN_DEBUG "%s cpu %d node %d: mask now %*pbl\n",
+ enable ? "numa_add_cpu" : "numa_remove_cpu",
+ cpu, node, cpumask_pr_args(mask));
+ return;
+}
+
+# ifndef CONFIG_NUMA_EMU
+static void numa_set_cpumask(int cpu, bool enable)
+{
+ debug_cpumask_set_cpu(cpu, early_cpu_to_node(cpu), enable);
+}
+
+void numa_add_cpu(int cpu)
+{
+ numa_set_cpumask(cpu, true);
+}
+
+void numa_remove_cpu(int cpu)
+{
+ numa_set_cpumask(cpu, false);
+}
+# endif /* !CONFIG_NUMA_EMU */
+
+/*
+ * Returns a pointer to the bitmask of CPUs on Node 'node'.
+ */
+const struct cpumask *cpumask_of_node(int node)
+{
+ if ((unsigned)node >= nr_node_ids) {
+ printk(KERN_WARNING
+ "cpumask_of_node(%d): (unsigned)node >= nr_node_ids(%u)\n",
+ node, nr_node_ids);
+ dump_stack();
+ return cpu_none_mask;
+ }
+ if (!cpumask_available(node_to_cpumask_map[node])) {
+ printk(KERN_WARNING
+ "cpumask_of_node(%d): no node_to_cpumask_map!\n",
+ node);
+ dump_stack();
+ return cpu_online_mask;
+ }
+ return node_to_cpumask_map[node];
+}
+EXPORT_SYMBOL(cpumask_of_node);
+
+#endif /* !CONFIG_DEBUG_PER_CPU_MAPS */
+
+#ifdef CONFIG_NUMA_KEEP_MEMINFO
+static int meminfo_to_nid(struct numa_meminfo *mi, u64 start)
+{
+ int i;
+
+ for (i = 0; i < mi->nr_blks; i++)
+ if (mi->blk[i].start <= start && mi->blk[i].end > start)
+ return mi->blk[i].nid;
+ return NUMA_NO_NODE;
+}
+
+int phys_to_target_node(phys_addr_t start)
+{
+ int nid = meminfo_to_nid(&numa_meminfo, start);
+
+ /*
+ * Prefer online nodes, but if reserved memory might be
+ * hot-added continue the search with reserved ranges.
+ */
+ if (nid != NUMA_NO_NODE)
+ return nid;
+
+ return meminfo_to_nid(&numa_reserved_meminfo, start);
+}
+EXPORT_SYMBOL_GPL(phys_to_target_node);
+
+int memory_add_physaddr_to_nid(u64 start)
+{
+ int nid = meminfo_to_nid(&numa_meminfo, start);
+
+ if (nid == NUMA_NO_NODE)
+ nid = numa_meminfo.blk[0].nid;
+ return nid;
+}
+EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
+
+static int __init cmp_memblk(const void *a, const void *b)
+{
+ const struct numa_memblk *ma = *(const struct numa_memblk **)a;
+ const struct numa_memblk *mb = *(const struct numa_memblk **)b;
+
+ return ma->start - mb->start;
+}
+
+static struct numa_memblk *numa_memblk_list[NR_NODE_MEMBLKS] __initdata;
+
+/**
+ * numa_fill_memblks - Fill gaps in numa_meminfo memblks
+ * @start: address to begin fill
+ * @end: address to end fill
+ *
+ * Find and extend numa_meminfo memblks to cover the @start-@end
+ * physical address range, such that the first memblk includes
+ * @start, the last memblk includes @end, and any gaps in between
+ * are filled.
+ *
+ * RETURNS:
+ * 0 : Success
+ * NUMA_NO_MEMBLK : No memblk exists in @start-@end range
+ */
+
+int __init numa_fill_memblks(u64 start, u64 end)
+{
+ struct numa_memblk **blk = &numa_memblk_list[0];
+ struct numa_meminfo *mi = &numa_meminfo;
+ int count = 0;
+ u64 prev_end;
+
+ /*
+ * Create a list of pointers to numa_meminfo memblks that
+ * overlap start, end. Exclude (start == bi->end) since
+ * end addresses in both a CFMWS range and a memblk range
+ * are exclusive.
+ *
+ * This list of pointers is used to make in-place changes
+ * that fill out the numa_meminfo memblks.
+ */
+ for (int i = 0; i < mi->nr_blks; i++) {
+ struct numa_memblk *bi = &mi->blk[i];
+
+ if (start < bi->end && end >= bi->start) {
+ blk[count] = &mi->blk[i];
+ count++;
+ }
+ }
+ if (!count)
+ return NUMA_NO_MEMBLK;
+
+ /* Sort the list of pointers in memblk->start order */
+ sort(&blk[0], count, sizeof(blk[0]), cmp_memblk, NULL);
+
+ /* Make sure the first/last memblks include start/end */
+ blk[0]->start = min(blk[0]->start, start);
+ blk[count - 1]->end = max(blk[count - 1]->end, end);
+
+ /*
+ * Fill any gaps by tracking the previous memblks
+ * end address and backfilling to it if needed.
+ */
+ prev_end = blk[0]->end;
+ for (int i = 1; i < count; i++) {
+ struct numa_memblk *curr = blk[i];
+
+ if (prev_end >= curr->start) {
+ if (prev_end < curr->end)
+ prev_end = curr->end;
+ } else {
+ curr->start = prev_end;
+ prev_end = curr->end;
+ }
+ }
+ return 0;
+}
+
+#endif