mm: introduce numa_emulation
authorMike Rapoport (Microsoft) <rppt@kernel.org>
Wed, 7 Aug 2024 06:41:03 +0000 (09:41 +0300)
committerAndrew Morton <akpm@linux-foundation.org>
Wed, 4 Sep 2024 04:15:31 +0000 (21:15 -0700)
Move numa_emulation code from arch/x86 to mm/numa_emulation.c

This code will be later reused by arch_numa.

No functional changes.

Link: https://lkml.kernel.org/r/20240807064110.1003856-20-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Tested-by: Zi Yan <ziy@nvidia.com> # for x86_64 and arm64
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> [arm64 + CXL via QEMU]
Acked-by: Dan Williams <dan.j.williams@intel.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Rob Herring (Arm) <robh@kernel.org>
Cc: Samuel Holland <samuel.holland@sifive.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
arch/x86/Kconfig
arch/x86/include/asm/numa.h
arch/x86/mm/Makefile
arch/x86/mm/numa_emulation.c [deleted file]
arch/x86/mm/numa_internal.h
include/linux/numa_memblks.h
mm/Kconfig
mm/Makefile
mm/numa_emulation.c [new file with mode: 0644]

index 74afb59c6603c8e1206ab3de6063be8a11ee263b..acd9745bf2aed032e52693ea511ad335b4bbea3c 100644 (file)
@@ -1600,14 +1600,6 @@ config X86_64_ACPI_NUMA
        help
          Enable ACPI SRAT based node topology detection.
 
-config NUMA_EMU
-       bool "NUMA emulation"
-       depends on NUMA
-       help
-         Enable NUMA emulation. A flat machine will be split
-         into virtual nodes when booted with "numa=fake=N", where N is the
-         number of nodes. This is only useful for debugging.
-
 config NODES_SHIFT
        int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
        range 1 10
index 203100500f240252e4c362c39c24e4c1e06bcda3..5469d7a7c40fa68d88da6167bcb14d4fa0b33535 100644 (file)
@@ -65,16 +65,4 @@ static inline void init_gi_nodes(void)                       { }
 void debug_cpumask_set_cpu(unsigned int cpu, int node, bool enable);
 #endif
 
-#ifdef CONFIG_NUMA_EMU
-int numa_emu_cmdline(char *str);
-void __init numa_emu_update_cpu_to_node(int *emu_nid_to_phys,
-                                       unsigned int nr_emu_nids);
-u64 __init numa_emu_dma_end(void);
-#else /* CONFIG_NUMA_EMU */
-static inline int numa_emu_cmdline(char *str)
-{
-       return -EINVAL;
-}
-#endif /* CONFIG_NUMA_EMU */
-
 #endif /* _ASM_X86_NUMA_H */
index 8d3a00e5c528e51578ee07663c315c0fcebe941b..690fbf48e8538b62a176ce838820e363575b7897 100644 (file)
@@ -57,7 +57,6 @@ obj-$(CONFIG_MMIOTRACE_TEST)  += testmmiotrace.o
 obj-$(CONFIG_NUMA)             += numa.o numa_$(BITS).o
 obj-$(CONFIG_AMD_NUMA)         += amdtopology.o
 obj-$(CONFIG_ACPI_NUMA)                += srat.o
-obj-$(CONFIG_NUMA_EMU)         += numa_emulation.o
 
 obj-$(CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS) += pkeys.o
 obj-$(CONFIG_RANDOMIZE_MEMORY)                 += kaslr.o
diff --git a/arch/x86/mm/numa_emulation.c b/arch/x86/mm/numa_emulation.c
deleted file mode 100644 (file)
index 3361002..0000000
+++ /dev/null
@@ -1,573 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * NUMA emulation
- */
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/topology.h>
-#include <linux/memblock.h>
-#include <linux/numa_memblks.h>
-#include <asm/dma.h>
-
-#include "numa_internal.h"
-
-#define FAKE_NODE_MIN_SIZE     ((u64)32 << 20)
-#define FAKE_NODE_MIN_HASH_MASK        (~(FAKE_NODE_MIN_SIZE - 1UL))
-
-static int emu_nid_to_phys[MAX_NUMNODES];
-static char *emu_cmdline __initdata;
-
-int __init numa_emu_cmdline(char *str)
-{
-       emu_cmdline = str;
-       return 0;
-}
-
-static int __init emu_find_memblk_by_nid(int nid, const struct numa_meminfo *mi)
-{
-       int i;
-
-       for (i = 0; i < mi->nr_blks; i++)
-               if (mi->blk[i].nid == nid)
-                       return i;
-       return -ENOENT;
-}
-
-static u64 __init mem_hole_size(u64 start, u64 end)
-{
-       unsigned long start_pfn = PFN_UP(start);
-       unsigned long end_pfn = PFN_DOWN(end);
-
-       if (start_pfn < end_pfn)
-               return PFN_PHYS(absent_pages_in_range(start_pfn, end_pfn));
-       return 0;
-}
-
-/*
- * Sets up nid to range from @start to @end.  The return value is -errno if
- * something went wrong, 0 otherwise.
- */
-static int __init emu_setup_memblk(struct numa_meminfo *ei,
-                                  struct numa_meminfo *pi,
-                                  int nid, int phys_blk, u64 size)
-{
-       struct numa_memblk *eb = &ei->blk[ei->nr_blks];
-       struct numa_memblk *pb = &pi->blk[phys_blk];
-
-       if (ei->nr_blks >= NR_NODE_MEMBLKS) {
-               pr_err("NUMA: Too many emulated memblks, failing emulation\n");
-               return -EINVAL;
-       }
-
-       ei->nr_blks++;
-       eb->start = pb->start;
-       eb->end = pb->start + size;
-       eb->nid = nid;
-
-       if (emu_nid_to_phys[nid] == NUMA_NO_NODE)
-               emu_nid_to_phys[nid] = pb->nid;
-
-       pb->start += size;
-       if (pb->start >= pb->end) {
-               WARN_ON_ONCE(pb->start > pb->end);
-               numa_remove_memblk_from(phys_blk, pi);
-       }
-
-       printk(KERN_INFO "Faking node %d at [mem %#018Lx-%#018Lx] (%LuMB)\n",
-              nid, eb->start, eb->end - 1, (eb->end - eb->start) >> 20);
-       return 0;
-}
-
-/*
- * Sets up nr_nodes fake nodes interleaved over physical nodes ranging from addr
- * to max_addr.
- *
- * Returns zero on success or negative on error.
- */
-static int __init split_nodes_interleave(struct numa_meminfo *ei,
-                                        struct numa_meminfo *pi,
-                                        u64 addr, u64 max_addr, int nr_nodes)
-{
-       nodemask_t physnode_mask = numa_nodes_parsed;
-       u64 size;
-       int big;
-       int nid = 0;
-       int i, ret;
-
-       if (nr_nodes <= 0)
-               return -1;
-       if (nr_nodes > MAX_NUMNODES) {
-               pr_info("numa=fake=%d too large, reducing to %d\n",
-                       nr_nodes, MAX_NUMNODES);
-               nr_nodes = MAX_NUMNODES;
-       }
-
-       /*
-        * Calculate target node size.  x86_32 freaks on __udivdi3() so do
-        * the division in ulong number of pages and convert back.
-        */
-       size = max_addr - addr - mem_hole_size(addr, max_addr);
-       size = PFN_PHYS((unsigned long)(size >> PAGE_SHIFT) / nr_nodes);
-
-       /*
-        * Calculate the number of big nodes that can be allocated as a result
-        * of consolidating the remainder.
-        */
-       big = ((size & ~FAKE_NODE_MIN_HASH_MASK) * nr_nodes) /
-               FAKE_NODE_MIN_SIZE;
-
-       size &= FAKE_NODE_MIN_HASH_MASK;
-       if (!size) {
-               pr_err("Not enough memory for each node.  "
-                       "NUMA emulation disabled.\n");
-               return -1;
-       }
-
-       /*
-        * Continue to fill physical nodes with fake nodes until there is no
-        * memory left on any of them.
-        */
-       while (!nodes_empty(physnode_mask)) {
-               for_each_node_mask(i, physnode_mask) {
-                       u64 dma32_end = numa_emu_dma_end();
-                       u64 start, limit, end;
-                       int phys_blk;
-
-                       phys_blk = emu_find_memblk_by_nid(i, pi);
-                       if (phys_blk < 0) {
-                               node_clear(i, physnode_mask);
-                               continue;
-                       }
-                       start = pi->blk[phys_blk].start;
-                       limit = pi->blk[phys_blk].end;
-                       end = start + size;
-
-                       if (nid < big)
-                               end += FAKE_NODE_MIN_SIZE;
-
-                       /*
-                        * Continue to add memory to this fake node if its
-                        * non-reserved memory is less than the per-node size.
-                        */
-                       while (end - start - mem_hole_size(start, end) < size) {
-                               end += FAKE_NODE_MIN_SIZE;
-                               if (end > limit) {
-                                       end = limit;
-                                       break;
-                               }
-                       }
-
-                       /*
-                        * If there won't be at least FAKE_NODE_MIN_SIZE of
-                        * non-reserved memory in ZONE_DMA32 for the next node,
-                        * this one must extend to the boundary.
-                        */
-                       if (end < dma32_end && dma32_end - end -
-                           mem_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE)
-                               end = dma32_end;
-
-                       /*
-                        * If there won't be enough non-reserved memory for the
-                        * next node, this one must extend to the end of the
-                        * physical node.
-                        */
-                       if (limit - end - mem_hole_size(end, limit) < size)
-                               end = limit;
-
-                       ret = emu_setup_memblk(ei, pi, nid++ % nr_nodes,
-                                              phys_blk,
-                                              min(end, limit) - start);
-                       if (ret < 0)
-                               return ret;
-               }
-       }
-       return 0;
-}
-
-/*
- * Returns the end address of a node so that there is at least `size' amount of
- * non-reserved memory or `max_addr' is reached.
- */
-static u64 __init find_end_of_node(u64 start, u64 max_addr, u64 size)
-{
-       u64 end = start + size;
-
-       while (end - start - mem_hole_size(start, end) < size) {
-               end += FAKE_NODE_MIN_SIZE;
-               if (end > max_addr) {
-                       end = max_addr;
-                       break;
-               }
-       }
-       return end;
-}
-
-static u64 uniform_size(u64 max_addr, u64 base, u64 hole, int nr_nodes)
-{
-       unsigned long max_pfn = PHYS_PFN(max_addr);
-       unsigned long base_pfn = PHYS_PFN(base);
-       unsigned long hole_pfns = PHYS_PFN(hole);
-
-       return PFN_PHYS((max_pfn - base_pfn - hole_pfns) / nr_nodes);
-}
-
-/*
- * Sets up fake nodes of `size' interleaved over physical nodes ranging from
- * `addr' to `max_addr'.
- *
- * Returns zero on success or negative on error.
- */
-static int __init split_nodes_size_interleave_uniform(struct numa_meminfo *ei,
-                                             struct numa_meminfo *pi,
-                                             u64 addr, u64 max_addr, u64 size,
-                                             int nr_nodes, struct numa_memblk *pblk,
-                                             int nid)
-{
-       nodemask_t physnode_mask = numa_nodes_parsed;
-       int i, ret, uniform = 0;
-       u64 min_size;
-
-       if ((!size && !nr_nodes) || (nr_nodes && !pblk))
-               return -1;
-
-       /*
-        * In the 'uniform' case split the passed in physical node by
-        * nr_nodes, in the non-uniform case, ignore the passed in
-        * physical block and try to create nodes of at least size
-        * @size.
-        *
-        * In the uniform case, split the nodes strictly by physical
-        * capacity, i.e. ignore holes. In the non-uniform case account
-        * for holes and treat @size as a minimum floor.
-        */
-       if (!nr_nodes)
-               nr_nodes = MAX_NUMNODES;
-       else {
-               nodes_clear(physnode_mask);
-               node_set(pblk->nid, physnode_mask);
-               uniform = 1;
-       }
-
-       if (uniform) {
-               min_size = uniform_size(max_addr, addr, 0, nr_nodes);
-               size = min_size;
-       } else {
-               /*
-                * The limit on emulated nodes is MAX_NUMNODES, so the
-                * size per node is increased accordingly if the
-                * requested size is too small.  This creates a uniform
-                * distribution of node sizes across the entire machine
-                * (but not necessarily over physical nodes).
-                */
-               min_size = uniform_size(max_addr, addr,
-                               mem_hole_size(addr, max_addr), nr_nodes);
-       }
-       min_size = ALIGN(max(min_size, FAKE_NODE_MIN_SIZE), FAKE_NODE_MIN_SIZE);
-       if (size < min_size) {
-               pr_err("Fake node size %LuMB too small, increasing to %LuMB\n",
-                       size >> 20, min_size >> 20);
-               size = min_size;
-       }
-       size = ALIGN_DOWN(size, FAKE_NODE_MIN_SIZE);
-
-       /*
-        * Fill physical nodes with fake nodes of size until there is no memory
-        * left on any of them.
-        */
-       while (!nodes_empty(physnode_mask)) {
-               for_each_node_mask(i, physnode_mask) {
-                       u64 dma32_end = numa_emu_dma_end();
-                       u64 start, limit, end;
-                       int phys_blk;
-
-                       phys_blk = emu_find_memblk_by_nid(i, pi);
-                       if (phys_blk < 0) {
-                               node_clear(i, physnode_mask);
-                               continue;
-                       }
-
-                       start = pi->blk[phys_blk].start;
-                       limit = pi->blk[phys_blk].end;
-
-                       if (uniform)
-                               end = start + size;
-                       else
-                               end = find_end_of_node(start, limit, size);
-                       /*
-                        * If there won't be at least FAKE_NODE_MIN_SIZE of
-                        * non-reserved memory in ZONE_DMA32 for the next node,
-                        * this one must extend to the boundary.
-                        */
-                       if (end < dma32_end && dma32_end - end -
-                           mem_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE)
-                               end = dma32_end;
-
-                       /*
-                        * If there won't be enough non-reserved memory for the
-                        * next node, this one must extend to the end of the
-                        * physical node.
-                        */
-                       if ((limit - end - mem_hole_size(end, limit) < size)
-                                       && !uniform)
-                               end = limit;
-
-                       ret = emu_setup_memblk(ei, pi, nid++ % MAX_NUMNODES,
-                                              phys_blk,
-                                              min(end, limit) - start);
-                       if (ret < 0)
-                               return ret;
-               }
-       }
-       return nid;
-}
-
-static int __init split_nodes_size_interleave(struct numa_meminfo *ei,
-                                             struct numa_meminfo *pi,
-                                             u64 addr, u64 max_addr, u64 size)
-{
-       return split_nodes_size_interleave_uniform(ei, pi, addr, max_addr, size,
-                       0, NULL, 0);
-}
-
-static int __init setup_emu2phys_nid(int *dfl_phys_nid)
-{
-       int i, max_emu_nid = 0;
-
-       *dfl_phys_nid = NUMA_NO_NODE;
-       for (i = 0; i < ARRAY_SIZE(emu_nid_to_phys); i++) {
-               if (emu_nid_to_phys[i] != NUMA_NO_NODE) {
-                       max_emu_nid = i;
-                       if (*dfl_phys_nid == NUMA_NO_NODE)
-                               *dfl_phys_nid = emu_nid_to_phys[i];
-               }
-       }
-
-       return max_emu_nid;
-}
-
-/**
- * numa_emulation - Emulate NUMA nodes
- * @numa_meminfo: NUMA configuration to massage
- * @numa_dist_cnt: The size of the physical NUMA distance table
- *
- * Emulate NUMA nodes according to the numa=fake kernel parameter.
- * @numa_meminfo contains the physical memory configuration and is modified
- * to reflect the emulated configuration on success.  @numa_dist_cnt is
- * used to determine the size of the physical distance table.
- *
- * On success, the following modifications are made.
- *
- * - @numa_meminfo is updated to reflect the emulated nodes.
- *
- * - __apicid_to_node[] is updated such that APIC IDs are mapped to the
- *   emulated nodes.
- *
- * - NUMA distance table is rebuilt to represent distances between emulated
- *   nodes.  The distances are determined considering how emulated nodes
- *   are mapped to physical nodes and match the actual distances.
- *
- * - emu_nid_to_phys[] reflects how emulated nodes are mapped to physical
- *   nodes.  This is used by numa_add_cpu() and numa_remove_cpu().
- *
- * If emulation is not enabled or fails, emu_nid_to_phys[] is filled with
- * identity mapping and no other modification is made.
- */
-void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt)
-{
-       static struct numa_meminfo ei __initdata;
-       static struct numa_meminfo pi __initdata;
-       const u64 max_addr = PFN_PHYS(max_pfn);
-       u8 *phys_dist = NULL;
-       size_t phys_size = numa_dist_cnt * numa_dist_cnt * sizeof(phys_dist[0]);
-       int max_emu_nid, dfl_phys_nid;
-       int i, j, ret;
-
-       if (!emu_cmdline)
-               goto no_emu;
-
-       memset(&ei, 0, sizeof(ei));
-       pi = *numa_meminfo;
-
-       for (i = 0; i < MAX_NUMNODES; i++)
-               emu_nid_to_phys[i] = NUMA_NO_NODE;
-
-       /*
-        * If the numa=fake command-line contains a 'M' or 'G', it represents
-        * the fixed node size.  Otherwise, if it is just a single number N,
-        * split the system RAM into N fake nodes.
-        */
-       if (strchr(emu_cmdline, 'U')) {
-               nodemask_t physnode_mask = numa_nodes_parsed;
-               unsigned long n;
-               int nid = 0;
-
-               n = simple_strtoul(emu_cmdline, &emu_cmdline, 0);
-               ret = -1;
-               for_each_node_mask(i, physnode_mask) {
-                       /*
-                        * The reason we pass in blk[0] is due to
-                        * numa_remove_memblk_from() called by
-                        * emu_setup_memblk() will delete entry 0
-                        * and then move everything else up in the pi.blk
-                        * array. Therefore we should always be looking
-                        * at blk[0].
-                        */
-                       ret = split_nodes_size_interleave_uniform(&ei, &pi,
-                                       pi.blk[0].start, pi.blk[0].end, 0,
-                                       n, &pi.blk[0], nid);
-                       if (ret < 0)
-                               break;
-                       if (ret < n) {
-                               pr_info("%s: phys: %d only got %d of %ld nodes, failing\n",
-                                               __func__, i, ret, n);
-                               ret = -1;
-                               break;
-                       }
-                       nid = ret;
-               }
-       } else if (strchr(emu_cmdline, 'M') || strchr(emu_cmdline, 'G')) {
-               u64 size;
-
-               size = memparse(emu_cmdline, &emu_cmdline);
-               ret = split_nodes_size_interleave(&ei, &pi, 0, max_addr, size);
-       } else {
-               unsigned long n;
-
-               n = simple_strtoul(emu_cmdline, &emu_cmdline, 0);
-               ret = split_nodes_interleave(&ei, &pi, 0, max_addr, n);
-       }
-       if (*emu_cmdline == ':')
-               emu_cmdline++;
-
-       if (ret < 0)
-               goto no_emu;
-
-       if (numa_cleanup_meminfo(&ei) < 0) {
-               pr_warn("NUMA: Warning: constructed meminfo invalid, disabling emulation\n");
-               goto no_emu;
-       }
-
-       /* copy the physical distance table */
-       if (numa_dist_cnt) {
-               phys_dist = memblock_alloc(phys_size, PAGE_SIZE);
-               if (!phys_dist) {
-                       pr_warn("NUMA: Warning: can't allocate copy of distance table, disabling emulation\n");
-                       goto no_emu;
-               }
-
-               for (i = 0; i < numa_dist_cnt; i++)
-                       for (j = 0; j < numa_dist_cnt; j++)
-                               phys_dist[i * numa_dist_cnt + j] =
-                                       node_distance(i, j);
-       }
-
-       /*
-        * Determine the max emulated nid and the default phys nid to use
-        * for unmapped nodes.
-        */
-       max_emu_nid = setup_emu2phys_nid(&dfl_phys_nid);
-
-       /* commit */
-       *numa_meminfo = ei;
-
-       /* Make sure numa_nodes_parsed only contains emulated nodes */
-       nodes_clear(numa_nodes_parsed);
-       for (i = 0; i < ARRAY_SIZE(ei.blk); i++)
-               if (ei.blk[i].start != ei.blk[i].end &&
-                   ei.blk[i].nid != NUMA_NO_NODE)
-                       node_set(ei.blk[i].nid, numa_nodes_parsed);
-
-       numa_emu_update_cpu_to_node(emu_nid_to_phys, ARRAY_SIZE(emu_nid_to_phys));
-
-       /* make sure all emulated nodes are mapped to a physical node */
-       for (i = 0; i < ARRAY_SIZE(emu_nid_to_phys); i++)
-               if (emu_nid_to_phys[i] == NUMA_NO_NODE)
-                       emu_nid_to_phys[i] = dfl_phys_nid;
-
-       /* transform distance table */
-       numa_reset_distance();
-       for (i = 0; i < max_emu_nid + 1; i++) {
-               for (j = 0; j < max_emu_nid + 1; j++) {
-                       int physi = emu_nid_to_phys[i];
-                       int physj = emu_nid_to_phys[j];
-                       int dist;
-
-                       if (get_option(&emu_cmdline, &dist) == 2)
-                               ;
-                       else if (physi >= numa_dist_cnt || physj >= numa_dist_cnt)
-                               dist = physi == physj ?
-                                       LOCAL_DISTANCE : REMOTE_DISTANCE;
-                       else
-                               dist = phys_dist[physi * numa_dist_cnt + physj];
-
-                       numa_set_distance(i, j, dist);
-               }
-       }
-
-       /* free the copied physical distance table */
-       memblock_free(phys_dist, phys_size);
-       return;
-
-no_emu:
-       /* No emulation.  Build identity emu_nid_to_phys[] for numa_add_cpu() */
-       for (i = 0; i < ARRAY_SIZE(emu_nid_to_phys); i++)
-               emu_nid_to_phys[i] = i;
-}
-
-#ifndef CONFIG_DEBUG_PER_CPU_MAPS
-void numa_add_cpu(unsigned int cpu)
-{
-       int physnid, nid;
-
-       nid = early_cpu_to_node(cpu);
-       BUG_ON(nid == NUMA_NO_NODE || !node_online(nid));
-
-       physnid = emu_nid_to_phys[nid];
-
-       /*
-        * Map the cpu to each emulated node that is allocated on the physical
-        * node of the cpu's apic id.
-        */
-       for_each_online_node(nid)
-               if (emu_nid_to_phys[nid] == physnid)
-                       cpumask_set_cpu(cpu, node_to_cpumask_map[nid]);
-}
-
-void numa_remove_cpu(unsigned int cpu)
-{
-       int i;
-
-       for_each_online_node(i)
-               cpumask_clear_cpu(cpu, node_to_cpumask_map[i]);
-}
-#else  /* !CONFIG_DEBUG_PER_CPU_MAPS */
-static void numa_set_cpumask(unsigned int cpu, bool enable)
-{
-       int nid, physnid;
-
-       nid = early_cpu_to_node(cpu);
-       if (nid == NUMA_NO_NODE) {
-               /* early_cpu_to_node() already emits a warning and trace */
-               return;
-       }
-
-       physnid = emu_nid_to_phys[nid];
-
-       for_each_online_node(nid) {
-               if (emu_nid_to_phys[nid] != physnid)
-                       continue;
-
-               debug_cpumask_set_cpu(cpu, nid, enable);
-       }
-}
-
-void numa_add_cpu(unsigned int cpu)
-{
-       numa_set_cpumask(cpu, true);
-}
-
-void numa_remove_cpu(unsigned int cpu)
-{
-       numa_set_cpumask(cpu, false);
-}
-#endif /* !CONFIG_DEBUG_PER_CPU_MAPS */
index 249e3aaeadce16a52fb45d0914ff53377b12eb52..11e1ff370c106fca2b0e75bacfbb5299b8eedfa4 100644 (file)
@@ -7,15 +7,4 @@
 
 void __init x86_numa_init(void);
 
-struct numa_meminfo;
-
-#ifdef CONFIG_NUMA_EMU
-void __init numa_emulation(struct numa_meminfo *numa_meminfo,
-                          int numa_dist_cnt);
-#else
-static inline void numa_emulation(struct numa_meminfo *numa_meminfo,
-                                 int numa_dist_cnt)
-{ }
-#endif
-
 #endif /* __X86_MM_NUMA_INTERNAL_H */
index 968a590535ac21118655fe6f3c75de8912339f2c..f81f986780749cd97a7b41242f75269a78ea35c5 100644 (file)
@@ -34,6 +34,23 @@ int __init numa_register_meminfo(struct numa_meminfo *mi);
 void __init numa_nodemask_from_meminfo(nodemask_t *nodemask,
                                       const struct numa_meminfo *mi);
 
+#ifdef CONFIG_NUMA_EMU
+int numa_emu_cmdline(char *str);
+void __init numa_emu_update_cpu_to_node(int *emu_nid_to_phys,
+                                       unsigned int nr_emu_nids);
+u64 __init numa_emu_dma_end(void);
+void __init numa_emulation(struct numa_meminfo *numa_meminfo,
+                          int numa_dist_cnt);
+#else
+static inline void numa_emulation(struct numa_meminfo *numa_meminfo,
+                                 int numa_dist_cnt)
+{ }
+static inline int numa_emu_cmdline(char *str)
+{
+       return -EINVAL;
+}
+#endif /* CONFIG_NUMA_EMU */
+
 #endif /* CONFIG_NUMA_MEMBLKS */
 
 #endif /* __NUMA_MEMBLKS_H */
index 67700a1279829a0ebedbe603dc0bf9e3c6dae855..3936fe4d26d91b69dde4868bc0377039989b1ab1 100644 (file)
@@ -1270,6 +1270,14 @@ config EXECMEM
 config NUMA_MEMBLKS
        bool
 
+config NUMA_EMU
+       bool "NUMA emulation"
+       depends on NUMA_MEMBLKS
+       help
+         Enable NUMA emulation. A flat machine will be split
+         into virtual nodes when booted with "numa=fake=N", where N is the
+         number of nodes. This is only useful for debugging.
+
 source "mm/damon/Kconfig"
 
 endmenu
index 0778dce4aef62bf6260abd2a67f41aa43bec7ecd..d5639b03616636e4d49913f76865e24edb270f73 100644 (file)
@@ -119,6 +119,7 @@ obj-$(CONFIG_GENERIC_EARLY_IOREMAP) += early_ioremap.o
 obj-$(CONFIG_CMA)      += cma.o
 obj-$(CONFIG_NUMA) += numa.o
 obj-$(CONFIG_NUMA_MEMBLKS) += numa_memblks.o
+obj-$(CONFIG_NUMA_EMU) += numa_emulation.o
 obj-$(CONFIG_MEMORY_BALLOON) += balloon_compaction.o
 obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o
 obj-$(CONFIG_PAGE_TABLE_CHECK) += page_table_check.o
diff --git a/mm/numa_emulation.c b/mm/numa_emulation.c
new file mode 100644 (file)
index 0000000..031fb99
--- /dev/null
@@ -0,0 +1,571 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * NUMA emulation
+ */
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/topology.h>
+#include <linux/memblock.h>
+#include <linux/numa_memblks.h>
+#include <asm/numa.h>
+
+#define FAKE_NODE_MIN_SIZE     ((u64)32 << 20)
+#define FAKE_NODE_MIN_HASH_MASK        (~(FAKE_NODE_MIN_SIZE - 1UL))
+
+static int emu_nid_to_phys[MAX_NUMNODES];
+static char *emu_cmdline __initdata;
+
+int __init numa_emu_cmdline(char *str)
+{
+       emu_cmdline = str;
+       return 0;
+}
+
+static int __init emu_find_memblk_by_nid(int nid, const struct numa_meminfo *mi)
+{
+       int i;
+
+       for (i = 0; i < mi->nr_blks; i++)
+               if (mi->blk[i].nid == nid)
+                       return i;
+       return -ENOENT;
+}
+
+static u64 __init mem_hole_size(u64 start, u64 end)
+{
+       unsigned long start_pfn = PFN_UP(start);
+       unsigned long end_pfn = PFN_DOWN(end);
+
+       if (start_pfn < end_pfn)
+               return PFN_PHYS(absent_pages_in_range(start_pfn, end_pfn));
+       return 0;
+}
+
+/*
+ * Sets up nid to range from @start to @end.  The return value is -errno if
+ * something went wrong, 0 otherwise.
+ */
+static int __init emu_setup_memblk(struct numa_meminfo *ei,
+                                  struct numa_meminfo *pi,
+                                  int nid, int phys_blk, u64 size)
+{
+       struct numa_memblk *eb = &ei->blk[ei->nr_blks];
+       struct numa_memblk *pb = &pi->blk[phys_blk];
+
+       if (ei->nr_blks >= NR_NODE_MEMBLKS) {
+               pr_err("NUMA: Too many emulated memblks, failing emulation\n");
+               return -EINVAL;
+       }
+
+       ei->nr_blks++;
+       eb->start = pb->start;
+       eb->end = pb->start + size;
+       eb->nid = nid;
+
+       if (emu_nid_to_phys[nid] == NUMA_NO_NODE)
+               emu_nid_to_phys[nid] = pb->nid;
+
+       pb->start += size;
+       if (pb->start >= pb->end) {
+               WARN_ON_ONCE(pb->start > pb->end);
+               numa_remove_memblk_from(phys_blk, pi);
+       }
+
+       printk(KERN_INFO "Faking node %d at [mem %#018Lx-%#018Lx] (%LuMB)\n",
+              nid, eb->start, eb->end - 1, (eb->end - eb->start) >> 20);
+       return 0;
+}
+
+/*
+ * Sets up nr_nodes fake nodes interleaved over physical nodes ranging from addr
+ * to max_addr.
+ *
+ * Returns zero on success or negative on error.
+ */
+static int __init split_nodes_interleave(struct numa_meminfo *ei,
+                                        struct numa_meminfo *pi,
+                                        u64 addr, u64 max_addr, int nr_nodes)
+{
+       nodemask_t physnode_mask = numa_nodes_parsed;
+       u64 size;
+       int big;
+       int nid = 0;
+       int i, ret;
+
+       if (nr_nodes <= 0)
+               return -1;
+       if (nr_nodes > MAX_NUMNODES) {
+               pr_info("numa=fake=%d too large, reducing to %d\n",
+                       nr_nodes, MAX_NUMNODES);
+               nr_nodes = MAX_NUMNODES;
+       }
+
+       /*
+        * Calculate target node size.  x86_32 freaks on __udivdi3() so do
+        * the division in ulong number of pages and convert back.
+        */
+       size = max_addr - addr - mem_hole_size(addr, max_addr);
+       size = PFN_PHYS((unsigned long)(size >> PAGE_SHIFT) / nr_nodes);
+
+       /*
+        * Calculate the number of big nodes that can be allocated as a result
+        * of consolidating the remainder.
+        */
+       big = ((size & ~FAKE_NODE_MIN_HASH_MASK) * nr_nodes) /
+               FAKE_NODE_MIN_SIZE;
+
+       size &= FAKE_NODE_MIN_HASH_MASK;
+       if (!size) {
+               pr_err("Not enough memory for each node.  "
+                       "NUMA emulation disabled.\n");
+               return -1;
+       }
+
+       /*
+        * Continue to fill physical nodes with fake nodes until there is no
+        * memory left on any of them.
+        */
+       while (!nodes_empty(physnode_mask)) {
+               for_each_node_mask(i, physnode_mask) {
+                       u64 dma32_end = numa_emu_dma_end();
+                       u64 start, limit, end;
+                       int phys_blk;
+
+                       phys_blk = emu_find_memblk_by_nid(i, pi);
+                       if (phys_blk < 0) {
+                               node_clear(i, physnode_mask);
+                               continue;
+                       }
+                       start = pi->blk[phys_blk].start;
+                       limit = pi->blk[phys_blk].end;
+                       end = start + size;
+
+                       if (nid < big)
+                               end += FAKE_NODE_MIN_SIZE;
+
+                       /*
+                        * Continue to add memory to this fake node if its
+                        * non-reserved memory is less than the per-node size.
+                        */
+                       while (end - start - mem_hole_size(start, end) < size) {
+                               end += FAKE_NODE_MIN_SIZE;
+                               if (end > limit) {
+                                       end = limit;
+                                       break;
+                               }
+                       }
+
+                       /*
+                        * If there won't be at least FAKE_NODE_MIN_SIZE of
+                        * non-reserved memory in ZONE_DMA32 for the next node,
+                        * this one must extend to the boundary.
+                        */
+                       if (end < dma32_end && dma32_end - end -
+                           mem_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE)
+                               end = dma32_end;
+
+                       /*
+                        * If there won't be enough non-reserved memory for the
+                        * next node, this one must extend to the end of the
+                        * physical node.
+                        */
+                       if (limit - end - mem_hole_size(end, limit) < size)
+                               end = limit;
+
+                       ret = emu_setup_memblk(ei, pi, nid++ % nr_nodes,
+                                              phys_blk,
+                                              min(end, limit) - start);
+                       if (ret < 0)
+                               return ret;
+               }
+       }
+       return 0;
+}
+
+/*
+ * Returns the end address of a node so that there is at least `size' amount of
+ * non-reserved memory or `max_addr' is reached.
+ */
+static u64 __init find_end_of_node(u64 start, u64 max_addr, u64 size)
+{
+       u64 end = start + size;
+
+       while (end - start - mem_hole_size(start, end) < size) {
+               end += FAKE_NODE_MIN_SIZE;
+               if (end > max_addr) {
+                       end = max_addr;
+                       break;
+               }
+       }
+       return end;
+}
+
+static u64 uniform_size(u64 max_addr, u64 base, u64 hole, int nr_nodes)
+{
+       unsigned long max_pfn = PHYS_PFN(max_addr);
+       unsigned long base_pfn = PHYS_PFN(base);
+       unsigned long hole_pfns = PHYS_PFN(hole);
+
+       return PFN_PHYS((max_pfn - base_pfn - hole_pfns) / nr_nodes);
+}
+
+/*
+ * Sets up fake nodes of `size' interleaved over physical nodes ranging from
+ * `addr' to `max_addr'.
+ *
+ * Returns zero on success or negative on error.
+ */
+static int __init split_nodes_size_interleave_uniform(struct numa_meminfo *ei,
+                                             struct numa_meminfo *pi,
+                                             u64 addr, u64 max_addr, u64 size,
+                                             int nr_nodes, struct numa_memblk *pblk,
+                                             int nid)
+{
+       nodemask_t physnode_mask = numa_nodes_parsed;
+       int i, ret, uniform = 0;
+       u64 min_size;
+
+       if ((!size && !nr_nodes) || (nr_nodes && !pblk))
+               return -1;
+
+       /*
+        * In the 'uniform' case split the passed in physical node by
+        * nr_nodes, in the non-uniform case, ignore the passed in
+        * physical block and try to create nodes of at least size
+        * @size.
+        *
+        * In the uniform case, split the nodes strictly by physical
+        * capacity, i.e. ignore holes. In the non-uniform case account
+        * for holes and treat @size as a minimum floor.
+        */
+       if (!nr_nodes)
+               nr_nodes = MAX_NUMNODES;
+       else {
+               nodes_clear(physnode_mask);
+               node_set(pblk->nid, physnode_mask);
+               uniform = 1;
+       }
+
+       if (uniform) {
+               min_size = uniform_size(max_addr, addr, 0, nr_nodes);
+               size = min_size;
+       } else {
+               /*
+                * The limit on emulated nodes is MAX_NUMNODES, so the
+                * size per node is increased accordingly if the
+                * requested size is too small.  This creates a uniform
+                * distribution of node sizes across the entire machine
+                * (but not necessarily over physical nodes).
+                */
+               min_size = uniform_size(max_addr, addr,
+                               mem_hole_size(addr, max_addr), nr_nodes);
+       }
+       min_size = ALIGN(max(min_size, FAKE_NODE_MIN_SIZE), FAKE_NODE_MIN_SIZE);
+       if (size < min_size) {
+               pr_err("Fake node size %LuMB too small, increasing to %LuMB\n",
+                       size >> 20, min_size >> 20);
+               size = min_size;
+       }
+       size = ALIGN_DOWN(size, FAKE_NODE_MIN_SIZE);
+
+       /*
+        * Fill physical nodes with fake nodes of size until there is no memory
+        * left on any of them.
+        */
+       while (!nodes_empty(physnode_mask)) {
+               for_each_node_mask(i, physnode_mask) {
+                       u64 dma32_end = numa_emu_dma_end();
+                       u64 start, limit, end;
+                       int phys_blk;
+
+                       phys_blk = emu_find_memblk_by_nid(i, pi);
+                       if (phys_blk < 0) {
+                               node_clear(i, physnode_mask);
+                               continue;
+                       }
+
+                       start = pi->blk[phys_blk].start;
+                       limit = pi->blk[phys_blk].end;
+
+                       if (uniform)
+                               end = start + size;
+                       else
+                               end = find_end_of_node(start, limit, size);
+                       /*
+                        * If there won't be at least FAKE_NODE_MIN_SIZE of
+                        * non-reserved memory in ZONE_DMA32 for the next node,
+                        * this one must extend to the boundary.
+                        */
+                       if (end < dma32_end && dma32_end - end -
+                           mem_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE)
+                               end = dma32_end;
+
+                       /*
+                        * If there won't be enough non-reserved memory for the
+                        * next node, this one must extend to the end of the
+                        * physical node.
+                        */
+                       if ((limit - end - mem_hole_size(end, limit) < size)
+                                       && !uniform)
+                               end = limit;
+
+                       ret = emu_setup_memblk(ei, pi, nid++ % MAX_NUMNODES,
+                                              phys_blk,
+                                              min(end, limit) - start);
+                       if (ret < 0)
+                               return ret;
+               }
+       }
+       return nid;
+}
+
+static int __init split_nodes_size_interleave(struct numa_meminfo *ei,
+                                             struct numa_meminfo *pi,
+                                             u64 addr, u64 max_addr, u64 size)
+{
+       return split_nodes_size_interleave_uniform(ei, pi, addr, max_addr, size,
+                       0, NULL, 0);
+}
+
+static int __init setup_emu2phys_nid(int *dfl_phys_nid)
+{
+       int i, max_emu_nid = 0;
+
+       *dfl_phys_nid = NUMA_NO_NODE;
+       for (i = 0; i < ARRAY_SIZE(emu_nid_to_phys); i++) {
+               if (emu_nid_to_phys[i] != NUMA_NO_NODE) {
+                       max_emu_nid = i;
+                       if (*dfl_phys_nid == NUMA_NO_NODE)
+                               *dfl_phys_nid = emu_nid_to_phys[i];
+               }
+       }
+
+       return max_emu_nid;
+}
+
+/**
+ * numa_emulation - Emulate NUMA nodes
+ * @numa_meminfo: NUMA configuration to massage
+ * @numa_dist_cnt: The size of the physical NUMA distance table
+ *
+ * Emulate NUMA nodes according to the numa=fake kernel parameter.
+ * @numa_meminfo contains the physical memory configuration and is modified
+ * to reflect the emulated configuration on success.  @numa_dist_cnt is
+ * used to determine the size of the physical distance table.
+ *
+ * On success, the following modifications are made.
+ *
+ * - @numa_meminfo is updated to reflect the emulated nodes.
+ *
+ * - __apicid_to_node[] is updated such that APIC IDs are mapped to the
+ *   emulated nodes.
+ *
+ * - NUMA distance table is rebuilt to represent distances between emulated
+ *   nodes.  The distances are determined considering how emulated nodes
+ *   are mapped to physical nodes and match the actual distances.
+ *
+ * - emu_nid_to_phys[] reflects how emulated nodes are mapped to physical
+ *   nodes.  This is used by numa_add_cpu() and numa_remove_cpu().
+ *
+ * If emulation is not enabled or fails, emu_nid_to_phys[] is filled with
+ * identity mapping and no other modification is made.
+ */
+void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt)
+{
+       static struct numa_meminfo ei __initdata;
+       static struct numa_meminfo pi __initdata;
+       const u64 max_addr = PFN_PHYS(max_pfn);
+       u8 *phys_dist = NULL;
+       size_t phys_size = numa_dist_cnt * numa_dist_cnt * sizeof(phys_dist[0]);
+       int max_emu_nid, dfl_phys_nid;
+       int i, j, ret;
+
+       if (!emu_cmdline)
+               goto no_emu;
+
+       memset(&ei, 0, sizeof(ei));
+       pi = *numa_meminfo;
+
+       for (i = 0; i < MAX_NUMNODES; i++)
+               emu_nid_to_phys[i] = NUMA_NO_NODE;
+
+       /*
+        * If the numa=fake command-line contains a 'M' or 'G', it represents
+        * the fixed node size.  Otherwise, if it is just a single number N,
+        * split the system RAM into N fake nodes.
+        */
+       if (strchr(emu_cmdline, 'U')) {
+               nodemask_t physnode_mask = numa_nodes_parsed;
+               unsigned long n;
+               int nid = 0;
+
+               n = simple_strtoul(emu_cmdline, &emu_cmdline, 0);
+               ret = -1;
+               for_each_node_mask(i, physnode_mask) {
+                       /*
+                        * The reason we pass in blk[0] is due to
+                        * numa_remove_memblk_from() called by
+                        * emu_setup_memblk() will delete entry 0
+                        * and then move everything else up in the pi.blk
+                        * array. Therefore we should always be looking
+                        * at blk[0].
+                        */
+                       ret = split_nodes_size_interleave_uniform(&ei, &pi,
+                                       pi.blk[0].start, pi.blk[0].end, 0,
+                                       n, &pi.blk[0], nid);
+                       if (ret < 0)
+                               break;
+                       if (ret < n) {
+                               pr_info("%s: phys: %d only got %d of %ld nodes, failing\n",
+                                               __func__, i, ret, n);
+                               ret = -1;
+                               break;
+                       }
+                       nid = ret;
+               }
+       } else if (strchr(emu_cmdline, 'M') || strchr(emu_cmdline, 'G')) {
+               u64 size;
+
+               size = memparse(emu_cmdline, &emu_cmdline);
+               ret = split_nodes_size_interleave(&ei, &pi, 0, max_addr, size);
+       } else {
+               unsigned long n;
+
+               n = simple_strtoul(emu_cmdline, &emu_cmdline, 0);
+               ret = split_nodes_interleave(&ei, &pi, 0, max_addr, n);
+       }
+       if (*emu_cmdline == ':')
+               emu_cmdline++;
+
+       if (ret < 0)
+               goto no_emu;
+
+       if (numa_cleanup_meminfo(&ei) < 0) {
+               pr_warn("NUMA: Warning: constructed meminfo invalid, disabling emulation\n");
+               goto no_emu;
+       }
+
+       /* copy the physical distance table */
+       if (numa_dist_cnt) {
+               phys_dist = memblock_alloc(phys_size, PAGE_SIZE);
+               if (!phys_dist) {
+                       pr_warn("NUMA: Warning: can't allocate copy of distance table, disabling emulation\n");
+                       goto no_emu;
+               }
+
+               for (i = 0; i < numa_dist_cnt; i++)
+                       for (j = 0; j < numa_dist_cnt; j++)
+                               phys_dist[i * numa_dist_cnt + j] =
+                                       node_distance(i, j);
+       }
+
+       /*
+        * Determine the max emulated nid and the default phys nid to use
+        * for unmapped nodes.
+        */
+       max_emu_nid = setup_emu2phys_nid(&dfl_phys_nid);
+
+       /* commit */
+       *numa_meminfo = ei;
+
+       /* Make sure numa_nodes_parsed only contains emulated nodes */
+       nodes_clear(numa_nodes_parsed);
+       for (i = 0; i < ARRAY_SIZE(ei.blk); i++)
+               if (ei.blk[i].start != ei.blk[i].end &&
+                   ei.blk[i].nid != NUMA_NO_NODE)
+                       node_set(ei.blk[i].nid, numa_nodes_parsed);
+
+       numa_emu_update_cpu_to_node(emu_nid_to_phys, ARRAY_SIZE(emu_nid_to_phys));
+
+       /* make sure all emulated nodes are mapped to a physical node */
+       for (i = 0; i < ARRAY_SIZE(emu_nid_to_phys); i++)
+               if (emu_nid_to_phys[i] == NUMA_NO_NODE)
+                       emu_nid_to_phys[i] = dfl_phys_nid;
+
+       /* transform distance table */
+       numa_reset_distance();
+       for (i = 0; i < max_emu_nid + 1; i++) {
+               for (j = 0; j < max_emu_nid + 1; j++) {
+                       int physi = emu_nid_to_phys[i];
+                       int physj = emu_nid_to_phys[j];
+                       int dist;
+
+                       if (get_option(&emu_cmdline, &dist) == 2)
+                               ;
+                       else if (physi >= numa_dist_cnt || physj >= numa_dist_cnt)
+                               dist = physi == physj ?
+                                       LOCAL_DISTANCE : REMOTE_DISTANCE;
+                       else
+                               dist = phys_dist[physi * numa_dist_cnt + physj];
+
+                       numa_set_distance(i, j, dist);
+               }
+       }
+
+       /* free the copied physical distance table */
+       memblock_free(phys_dist, phys_size);
+       return;
+
+no_emu:
+       /* No emulation.  Build identity emu_nid_to_phys[] for numa_add_cpu() */
+       for (i = 0; i < ARRAY_SIZE(emu_nid_to_phys); i++)
+               emu_nid_to_phys[i] = i;
+}
+
+#ifndef CONFIG_DEBUG_PER_CPU_MAPS
+void numa_add_cpu(unsigned int cpu)
+{
+       int physnid, nid;
+
+       nid = early_cpu_to_node(cpu);
+       BUG_ON(nid == NUMA_NO_NODE || !node_online(nid));
+
+       physnid = emu_nid_to_phys[nid];
+
+       /*
+        * Map the cpu to each emulated node that is allocated on the physical
+        * node of the cpu's apic id.
+        */
+       for_each_online_node(nid)
+               if (emu_nid_to_phys[nid] == physnid)
+                       cpumask_set_cpu(cpu, node_to_cpumask_map[nid]);
+}
+
+void numa_remove_cpu(unsigned int cpu)
+{
+       int i;
+
+       for_each_online_node(i)
+               cpumask_clear_cpu(cpu, node_to_cpumask_map[i]);
+}
+#else  /* !CONFIG_DEBUG_PER_CPU_MAPS */
+static void numa_set_cpumask(unsigned int cpu, bool enable)
+{
+       int nid, physnid;
+
+       nid = early_cpu_to_node(cpu);
+       if (nid == NUMA_NO_NODE) {
+               /* early_cpu_to_node() already emits a warning and trace */
+               return;
+       }
+
+       physnid = emu_nid_to_phys[nid];
+
+       for_each_online_node(nid) {
+               if (emu_nid_to_phys[nid] != physnid)
+                       continue;
+
+               debug_cpumask_set_cpu(cpu, nid, enable);
+       }
+}
+
+void numa_add_cpu(unsigned int cpu)
+{
+       numa_set_cpumask(cpu, true);
+}
+
+void numa_remove_cpu(unsigned int cpu)
+{
+       numa_set_cpumask(cpu, false);
+}
+#endif /* !CONFIG_DEBUG_PER_CPU_MAPS */