From mboxrd@z Thu Jan 1 00:00:00 1970 From: gpkulkarni@gmail.com (Ganapatrao Kulkarni) Date: Thu, 3 Sep 2015 15:22:02 +0530 Subject: [PATCH v5 1/4] arm64, numa: adding numa support for arm64 platforms. In-Reply-To: <1439570374-4079-2-git-send-email-gkulkarni@caviumnetworks.com> References: <1439570374-4079-1-git-send-email-gkulkarni@caviumnetworks.com> <1439570374-4079-2-git-send-email-gkulkarni@caviumnetworks.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Catalin/Will, On Fri, Aug 14, 2015 at 10:09 PM, Ganapatrao Kulkarni wrote: > Adding numa support for arm64 based platforms. > This patch adds by default the dummy numa node and > maps all memory and cpus to node 0. > using this patch, numa can be simulated on single node arm64 platforms. > > Signed-off-by: Ganapatrao Kulkarni > --- > arch/arm64/Kconfig | 26 ++ > arch/arm64/include/asm/mmzone.h | 32 +++ > arch/arm64/include/asm/numa.h | 42 +++ > arch/arm64/kernel/setup.c | 9 + > arch/arm64/kernel/smp.c | 2 + > arch/arm64/mm/Makefile | 1 + > arch/arm64/mm/init.c | 34 ++- > arch/arm64/mm/numa.c | 550 ++++++++++++++++++++++++++++++++++++++++ > 8 files changed, 690 insertions(+), 6 deletions(-) > create mode 100644 arch/arm64/include/asm/mmzone.h > create mode 100644 arch/arm64/include/asm/numa.h > create mode 100644 arch/arm64/mm/numa.c > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index 43a0c26..fa37a5d 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -72,6 +72,7 @@ config ARM64 > select HAVE_PERF_USER_STACK_DUMP > select HAVE_RCU_TABLE_FREE > select HAVE_SYSCALL_TRACEPOINTS > + select HAVE_MEMBLOCK_NODE_MAP if NUMA > select IRQ_DOMAIN > select IRQ_FORCED_THREADING > select MODULES_USE_ELF_RELA > @@ -559,6 +560,31 @@ config HOTPLUG_CPU > Say Y here to experiment with turning CPUs off and on. CPUs > can be controlled through /sys/devices/system/cpu. > > +# Common NUMA Features > +config NUMA > + bool "Numa Memory Allocation and Scheduler Support" > + depends on SMP > + help > + Enable NUMA (Non Uniform Memory Access) support. > + > + The kernel will try to allocate memory used by a CPU on the > + local memory controller of the CPU and add some more > + NUMA awareness to the kernel. > + > +config NODES_SHIFT > + int "Maximum NUMA Nodes (as a power of 2)" > + range 1 10 > + default "2" > + depends on NEED_MULTIPLE_NODES > + help > + Specify the maximum number of NUMA Nodes available on the target > + system. Increases memory reserved to accommodate various tables. > + > +config USE_PERCPU_NUMA_NODE_ID > + def_bool y > + depends on NUMA > + > + > source kernel/Kconfig.preempt > > config UP_LATE_INIT > diff --git a/arch/arm64/include/asm/mmzone.h b/arch/arm64/include/asm/mmzone.h > new file mode 100644 > index 0000000..d27ee66 > --- /dev/null > +++ b/arch/arm64/include/asm/mmzone.h > @@ -0,0 +1,32 @@ > +#ifndef __ASM_ARM64_MMZONE_H_ > +#define __ASM_ARM64_MMZONE_H_ > + > +#ifdef CONFIG_NUMA > + > +#include > +#include > +#include > +#include > + > +extern struct pglist_data *node_data[]; > + > +#define NODE_DATA(nid) (node_data[nid]) > + > + > +struct numa_memblk { > + u64 start; > + u64 end; > + int nid; > +}; > + > +struct numa_meminfo { > + int nr_blks; > + struct numa_memblk blk[NR_NODE_MEMBLKS]; > +}; > + > +void __init numa_remove_memblk_from(int idx, struct numa_meminfo *mi); > +int __init numa_cleanup_meminfo(struct numa_meminfo *mi); > +void __init numa_reset_distance(void); > + > +#endif /* CONFIG_NUMA */ > +#endif /* __ASM_ARM64_MMZONE_H_ */ > diff --git a/arch/arm64/include/asm/numa.h b/arch/arm64/include/asm/numa.h > new file mode 100644 > index 0000000..59b834e > --- /dev/null > +++ b/arch/arm64/include/asm/numa.h > @@ -0,0 +1,42 @@ > +#ifndef _ASM_NUMA_H > +#define _ASM_NUMA_H > + > +#include > +#include > + > +#ifdef CONFIG_NUMA > + > +#define NR_NODE_MEMBLKS (MAX_NUMNODES * 2) > +#define ZONE_ALIGN (1UL << (MAX_ORDER + PAGE_SHIFT)) > + > +/* currently, arm64 implements flat NUMA topology */ > +#define parent_node(node) (node) > + > +/* dummy definitions for pci functions */ > +#define pcibus_to_node(node) 0 > +#define cpumask_of_pcibus(bus) 0 > + > +struct __node_cpu_hwid { > + u32 node_id; /* logical node containing this CPU */ > + u64 cpu_hwid; /* MPIDR for this CPU */ > +}; > + > +extern struct __node_cpu_hwid node_cpu_hwid[NR_CPUS]; > +extern nodemask_t numa_nodes_parsed __initdata; > + > +const struct cpumask *cpumask_of_node(int node); > +/* Mappings between node number and cpus on that node. */ > +extern cpumask_var_t node_to_cpumask_map[MAX_NUMNODES]; > + > +void __init arm64_numa_init(void); > +int __init numa_add_memblk(u32 nodeid, u64 start, u64 end); > +void numa_store_cpu_info(int cpu); > +void __init build_cpu_to_node_map(void); > +void __init numa_set_distance(int from, int to, int distance); > +#else /* CONFIG_NUMA */ > +static inline void numa_store_cpu_info(int cpu) { } > +static inline void arm64_numa_init(void) { } > +static inline void build_cpu_to_node_map(void) { } > +static inline void numa_set_distance(int from, int to, int distance) { } > +#endif /* CONFIG_NUMA */ > +#endif /* _ASM_NUMA_H */ > diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c > index 4d4d7ce..6e101eb 100644 > --- a/arch/arm64/kernel/setup.c > +++ b/arch/arm64/kernel/setup.c > @@ -65,6 +65,7 @@ > #include > #include > #include > +#include > > unsigned long elf_hwcap __read_mostly; > EXPORT_SYMBOL_GPL(elf_hwcap); > @@ -439,6 +440,9 @@ static int __init topology_init(void) > { > int i; > > + for_each_online_node(i) > + register_one_node(i); > + > for_each_possible_cpu(i) { > struct cpu *cpu = &per_cpu(cpu_data.cpu, i); > cpu->hotpluggable = 1; > @@ -511,7 +515,12 @@ static int c_show(struct seq_file *m, void *v) > * "processor". Give glibc what it expects. > */ > #ifdef CONFIG_SMP > + if (IS_ENABLED(CONFIG_NUMA)) { > + seq_printf(m, "processor\t: %d", i); > + seq_printf(m, " [nid: %d]\n", cpu_to_node(i)); > + } else { > seq_printf(m, "processor\t: %d\n", i); > + } > #endif > > /* > diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c > index 50fb469..ae3e02c 100644 > --- a/arch/arm64/kernel/smp.c > +++ b/arch/arm64/kernel/smp.c > @@ -52,6 +52,7 @@ > #include > #include > #include > +#include > > #define CREATE_TRACE_POINTS > #include > @@ -124,6 +125,7 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) > static void smp_store_cpu_info(unsigned int cpuid) > { > store_cpu_topology(cpuid); > + numa_store_cpu_info(cpuid); > } > > /* > diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile > index 773d37a..bb92d41 100644 > --- a/arch/arm64/mm/Makefile > +++ b/arch/arm64/mm/Makefile > @@ -4,3 +4,4 @@ obj-y := dma-mapping.o extable.o fault.o init.o \ > context.o proc.o pageattr.o > obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o > obj-$(CONFIG_ARM64_PTDUMP) += dump.o > +obj-$(CONFIG_NUMA) += numa.o > diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c > index 54da32e..cab384b 100644 > --- a/arch/arm64/mm/init.c > +++ b/arch/arm64/mm/init.c > @@ -42,6 +42,7 @@ > #include > #include > #include > +#include > > #include "mm.h" > > @@ -77,6 +78,20 @@ static phys_addr_t max_zone_dma_phys(void) > return min(offset + (1ULL << 32), memblock_end_of_DRAM()); > } > > +#ifdef CONFIG_NUMA > +static void __init zone_sizes_init(unsigned long min, unsigned long max) > +{ > + unsigned long max_zone_pfns[MAX_NR_ZONES]; > + > + memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); > + if (IS_ENABLED(CONFIG_ZONE_DMA)) > + max_zone_pfns[ZONE_DMA] = PFN_DOWN(max_zone_dma_phys()); > + max_zone_pfns[ZONE_NORMAL] = max; > + > + free_area_init_nodes(max_zone_pfns); > +} > + > +#else > static void __init zone_sizes_init(unsigned long min, unsigned long max) > { > struct memblock_region *reg; > @@ -115,6 +130,7 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max) > > free_area_init_node(0, zone_size, min, zhole_size); > } > +#endif /* CONFIG_NUMA */ > > #ifdef CONFIG_HAVE_ARCH_PFN_VALID > int pfn_valid(unsigned long pfn) > @@ -132,10 +148,15 @@ static void arm64_memory_present(void) > static void arm64_memory_present(void) > { > struct memblock_region *reg; > + int nid = 0; > > - for_each_memblock(memory, reg) > - memory_present(0, memblock_region_memory_base_pfn(reg), > - memblock_region_memory_end_pfn(reg)); > + for_each_memblock(memory, reg) { > +#ifdef CONFIG_NUMA > + nid = reg->nid; > +#endif > + memory_present(nid, memblock_region_memory_base_pfn(reg), > + memblock_region_memory_end_pfn(reg)); > + } > } > #endif > > @@ -200,6 +221,10 @@ void __init bootmem_init(void) > min = PFN_UP(memblock_start_of_DRAM()); > max = PFN_DOWN(memblock_end_of_DRAM()); > > + high_memory = __va((max << PAGE_SHIFT) - 1) + 1; > + max_pfn = max_low_pfn = max; > + > + arm64_numa_init(); > /* > * Sparsemem tries to allocate bootmem in memory_present(), so must be > * done after the fixed reservations. > @@ -208,9 +233,6 @@ void __init bootmem_init(void) > > sparse_init(); > zone_sizes_init(min, max); > - > - high_memory = __va((max << PAGE_SHIFT) - 1) + 1; > - max_pfn = max_low_pfn = max; > } > > #ifndef CONFIG_SPARSEMEM_VMEMMAP > diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c > new file mode 100644 > index 0000000..2be83de > --- /dev/null > +++ b/arch/arm64/mm/numa.c > @@ -0,0 +1,550 @@ > +/* > + * NUMA support, based on the x86 implementation. > + * > + * Copyright (C) 2015 Cavium Inc. > + * Author: Ganapatrao Kulkarni > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program. If not, see . > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > + > +int __initdata numa_off; > +nodemask_t numa_nodes_parsed __initdata; > +static int numa_distance_cnt; > +static u8 *numa_distance; > +static u8 dummy_numa_enabled; > + > +struct pglist_data *node_data[MAX_NUMNODES] __read_mostly; > +EXPORT_SYMBOL(node_data); > + > +struct __node_cpu_hwid node_cpu_hwid[NR_CPUS]; > +static struct numa_meminfo numa_meminfo; > + > +static __init int numa_setup(char *opt) > +{ > + if (!opt) > + return -EINVAL; > + if (!strncmp(opt, "off", 3)) { > + pr_info("%s\n", "NUMA turned off"); > + numa_off = 1; > + } > + return 0; > +} > +early_param("numa", numa_setup); > + > +cpumask_var_t node_to_cpumask_map[MAX_NUMNODES]; > +EXPORT_SYMBOL(node_to_cpumask_map); > + > +int cpu_to_node_map[NR_CPUS]; > +EXPORT_SYMBOL(cpu_to_node_map); > + > +/* > + * Returns a pointer to the bitmask of CPUs on Node 'node'. > + */ > +const struct cpumask *cpumask_of_node(int node) > +{ > + if (node >= nr_node_ids) { > + pr_warn("cpumask_of_node(%d): node > nr_node_ids(%d)\n", > + node, nr_node_ids); > + dump_stack(); > + return cpu_none_mask; > + } > + if (node_to_cpumask_map[node] == NULL) { > + pr_warn("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); > + > +void numa_clear_node(int cpu) > +{ > + set_cpu_numa_node(cpu, NUMA_NO_NODE); > +} > + > +void map_cpu_to_node(int cpu, int nid) > +{ > + if (nid < 0) { /* just initialize by zero */ > + cpu_to_node_map[cpu] = 0; > + return; > + } > + > + cpu_to_node_map[cpu] = nid; > + cpumask_set_cpu(cpu, node_to_cpumask_map[nid]); > + set_numa_node(nid); > +} > + > +/** > + * build_cpu_to_node_map - setup cpu to node and node to cpumask arrays > + * > + * Build cpu to node mapping and initialize the per node cpu masks using > + * info from the node_cpuid array handed to us by ACPI or DT. > + */ > +void __init build_cpu_to_node_map(void) > +{ > + int cpu, i, node; > + > + for (node = 0; node < MAX_NUMNODES; node++) > + cpumask_clear(node_to_cpumask_map[node]); > + > + for_each_possible_cpu(cpu) { > + node = NUMA_NO_NODE; > + for_each_possible_cpu(i) { > + if (cpu_logical_map(cpu) == node_cpu_hwid[i].cpu_hwid) { > + node = node_cpu_hwid[i].node_id; > + break; > + } > + } > + map_cpu_to_node(cpu, 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 %d nodes\n", nr_node_ids); > +} > + > +/* > + * Set the cpu to node and mem mapping > + */ > +void numa_store_cpu_info(int cpu) > +{ > + if (dummy_numa_enabled) { > + /* set to default */ > + node_cpu_hwid[cpu].node_id = 0; > + node_cpu_hwid[cpu].cpu_hwid = cpu_logical_map(cpu); > + } > + map_cpu_to_node(cpu, node_cpu_hwid[cpu].node_id); > +} > + > +/** > + * numa_add_memblk_to - Add one numa_memblk to a numa_meminfo > + */ > + > +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("NUMA: Warning: invalid memblk node %d [mem %#010Lx-%#010Lx]\n", > + nid, start, end - 1); > + return 0; > + } > + > + if (mi->nr_blks >= NR_NODE_MEMBLKS) { > + pr_err("NUMA: too many memblk ranges\n"); > + return -EINVAL; > + } > + > + pr_info("NUMA: Adding memblock %d [0x%llx - 0x%llx] on node %d\n", > + mi->nr_blks, start, end, nid); > + 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_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. > + */ > +#define MAX_PHYS_ADDR ((phys_addr_t)~0) > + > +int __init numa_add_memblk(u32 nid, u64 base, u64 end) > +{ > + const u64 phys_offset = __pa(PAGE_OFFSET); > + > + base &= PAGE_MASK; > + end &= PAGE_MASK; > + > + if (base > MAX_PHYS_ADDR) { > + pr_warn("NUMA: Ignoring memory block 0x%llx - 0x%llx\n", > + base, base + end); > + return -ENOMEM; > + } > + > + if (base + end > MAX_PHYS_ADDR) { > + pr_info("NUMA: Ignoring memory range 0x%lx - 0x%llx\n", > + ULONG_MAX, base + end); > + end = MAX_PHYS_ADDR - base; > + } > + > + if (base + end < phys_offset) { > + pr_warn("NUMA: Ignoring memory block 0x%llx - 0x%llx\n", > + base, base + end); > + return -ENOMEM; > + } > + if (base < phys_offset) { > + pr_info("NUMA: Ignoring memory range 0x%llx - 0x%llx\n", > + base, phys_offset); > + end -= phys_offset - base; > + base = phys_offset; > + } > + > + return numa_add_memblk_to(nid, base, base + end, &numa_meminfo); > +} > +EXPORT_SYMBOL(numa_add_memblk); > + > +/* Initialize NODE_DATA for a node on the local memory */ > +static void __init setup_node_data(int nid, u64 start, u64 end) > +{ > + const size_t nd_size = roundup(sizeof(pg_data_t), PAGE_SIZE); > + u64 nd_pa; > + void *nd; > + int tnid; > + > + start = roundup(start, ZONE_ALIGN); > + > + pr_info("Initmem setup node %d [mem %#010Lx-%#010Lx]\n", > + nid, start, end - 1); > + > + /* > + * Allocate node data. Try node-local memory and then any node. > + */ > + nd_pa = memblock_alloc_nid(nd_size, SMP_CACHE_BYTES, nid); > + if (!nd_pa) { > + nd_pa = __memblock_alloc_base(nd_size, SMP_CACHE_BYTES, > + MEMBLOCK_ALLOC_ACCESSIBLE); > + if (!nd_pa) { > + pr_err("Cannot find %zu bytes in node %d\n", > + nd_size, nid); > + return; > + } > + } > + 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 >> PAGE_SHIFT; > + NODE_DATA(nid)->node_spanned_pages = (end - start) >> PAGE_SHIFT; > + > + node_set_online(nid); > +} > + > +/* > + * 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); > +} > + > +/* > + * 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, totalram; > + 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; > + } > + > + totalram = max_pfn - absent_pages_in_range(0, max_pfn); > + > + /* We seem to lose 3 pages somewhere. Allow 1M of slack. */ > + if ((s64)(totalram - numaram) >= (1 << (20 - PAGE_SHIFT))) { > + pr_err("NUMA: nodes only cover %lluMB of your %lluMB Total RAM. Not used.\n", > + (numaram << PAGE_SHIFT) >> 20, > + (totalram << PAGE_SHIFT) >> 20); > + return false; > + } > + return true; > +} > + > +/** > + * 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(__pa(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_find_in_range(0, PFN_PHYS(max_pfn), > + size, PAGE_SIZE); > + if (!phys) { > + pr_warn("NUMA: Warning: can't allocate distance table!\n"); > + /* don't retry until explicitly reset */ > + numa_distance = (void *)1LU; > + return -ENOMEM; > + } > + memblock_reserve(phys, size); > + > + 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; > + pr_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("NUMA: 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("NUMA: Warning: invalid distance parameter, from=%d to=%d distance=%d\n", > + from, to, distance); > + return; > + } > + > + numa_distance[from * numa_distance_cnt + to] = distance; > +} > +EXPORT_SYMBOL(numa_set_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); > + > +static int __init numa_register_memblks(struct numa_meminfo *mi) > +{ > + unsigned long uninitialized_var(pfn_align); > + 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); > + } > + > + /* > + * If sections array is gonna be used for pfn -> nid mapping, check > + * whether its granularity is fine enough. > + */ > +#ifdef NODE_NOT_IN_PAGE_FLAGS > + pfn_align = node_map_pfn_alignment(); > + if (pfn_align && pfn_align < PAGES_PER_SECTION) { > + pr_warn("Node alignment %lluMB < min %lluMB, rejecting NUMA config\n", > + PFN_PHYS(pfn_align) >> 20, > + PFN_PHYS(PAGES_PER_SECTION) >> 20); > + return -EINVAL; > + } > +#endif > + 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) > + setup_node_data(nid, start, end); > + } > + > + /* Dump memblock with node info and return. */ > + memblock_dump_all(); > + return 0; > +} > + > +static int __init numa_init(int (*init_func)(void)) > +{ > + int ret, i; > + > + nodes_clear(numa_nodes_parsed); > + nodes_clear(node_possible_map); > + nodes_clear(node_online_map); > + > + ret = init_func(); > + if (ret < 0) > + return ret; > + > + ret = numa_register_memblks(&numa_meminfo); > + if (ret < 0) > + return ret; > + > + for (i = 0; i < nr_cpu_ids; i++) > + numa_clear_node(i); > + > + setup_node_to_cpumask_map(); > + build_cpu_to_node_map(); > + 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) > +{ > + pr_info("%s\n", "No NUMA configuration found"); > + pr_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)); > + dummy_numa_enabled = 1; > + > + return 0; > +} > + > +/** > + * arm64_numa_init - Initialize NUMA > + * > + * Try each configured NUMA initialization method until one succeeds. The > + * last fallback is dummy single node config encomapssing whole memory and > + * never fails. > + */ > +void __init arm64_numa_init(void) > +{ > + numa_init(dummy_numa_init); > +} > -- > 1.8.1.4 > can you please review this patch. thanks Ganapat