From: David Hildenbrand <david@xxxxxxxxxx> Subject: drivers/base/node: consolidate node device subsystem initialization in node_dev_init() ... and call node_dev_init() after memory_dev_init() from driver_init(), so before any of the existing arch/subsys calls. All online nodes should be known at that point: early during boot, arch code determines node and zone ranges and sets the relevant nodes online; usually this happens in setup_arch(). This is in line with memory_dev_init(), which initializes the memory device subsystem and creates all memory block devices. Similar to memory_dev_init(), panic() if anything goes wrong, we don't want to continue with such basic initialization errors. The important part is that node_dev_init() gets called after memory_dev_init() and after cpu_dev_init(), but before any of the relevant archs call register_cpu() to register the new cpu device under the node device. The latter should be the case for the current users of topology_init(). Link: https://lkml.kernel.org/r/20220203105212.30385-1-david@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Reviewed-by: Oscar Salvador <osalvador@xxxxxxx> Tested-by: Anatoly Pugachev <matorola@xxxxxxxxx> (sparc64) Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx> Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx> Cc: Albert Ou <aou@xxxxxxxxxxxxxxxxx> Cc: Heiko Carstens <hca@xxxxxxxxxxxxx> Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx> Cc: Rich Felker <dalias@xxxxxxxx> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/arm64/kernel/setup.c | 3 --- arch/ia64/kernel/topology.c | 10 ---------- arch/mips/kernel/topology.c | 5 ----- arch/powerpc/kernel/sysfs.c | 17 ----------------- arch/riscv/kernel/setup.c | 3 --- arch/s390/kernel/numa.c | 7 ------- arch/sh/kernel/topology.c | 5 ----- arch/sparc/kernel/sysfs.c | 12 ------------ arch/x86/kernel/topology.c | 5 ----- drivers/base/init.c | 1 + drivers/base/node.c | 30 +++++++++++++++++------------- include/linux/node.h | 4 ++++ 12 files changed, 22 insertions(+), 80 deletions(-) --- a/arch/arm64/kernel/setup.c~drivers-base-node-consolidate-node-device-subsystem-initialization-in-node_dev_init +++ a/arch/arm64/kernel/setup.c @@ -406,9 +406,6 @@ 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 = cpu_can_disable(i); --- a/arch/ia64/kernel/topology.c~drivers-base-node-consolidate-node-device-subsystem-initialization-in-node_dev_init +++ a/arch/ia64/kernel/topology.c @@ -70,16 +70,6 @@ static int __init topology_init(void) { int i, err = 0; -#ifdef CONFIG_NUMA - /* - * MCD - Do we want to register all ONLINE nodes, or all POSSIBLE nodes? - */ - for_each_online_node(i) { - if ((err = register_one_node(i))) - goto out; - } -#endif - sysfs_cpus = kcalloc(NR_CPUS, sizeof(struct ia64_cpu), GFP_KERNEL); if (!sysfs_cpus) panic("kzalloc in topology_init failed - NR_CPUS too big?"); --- a/arch/mips/kernel/topology.c~drivers-base-node-consolidate-node-device-subsystem-initialization-in-node_dev_init +++ a/arch/mips/kernel/topology.c @@ -12,11 +12,6 @@ static int __init topology_init(void) { int i, ret; -#ifdef CONFIG_NUMA - for_each_online_node(i) - register_one_node(i); -#endif /* CONFIG_NUMA */ - for_each_present_cpu(i) { struct cpu *c = &per_cpu(cpu_devices, i); --- a/arch/powerpc/kernel/sysfs.c~drivers-base-node-consolidate-node-device-subsystem-initialization-in-node_dev_init +++ a/arch/powerpc/kernel/sysfs.c @@ -1110,14 +1110,6 @@ EXPORT_SYMBOL_GPL(cpu_remove_dev_attr_gr /* NUMA stuff */ #ifdef CONFIG_NUMA -static void __init register_nodes(void) -{ - int i; - - for (i = 0; i < MAX_NUMNODES; i++) - register_one_node(i); -} - int sysfs_add_device_to_node(struct device *dev, int nid) { struct node *node = node_devices[nid]; @@ -1132,13 +1124,6 @@ void sysfs_remove_device_from_node(struc sysfs_remove_link(&node->dev.kobj, kobject_name(&dev->kobj)); } EXPORT_SYMBOL_GPL(sysfs_remove_device_from_node); - -#else -static void __init register_nodes(void) -{ - return; -} - #endif /* Only valid if CPU is present. */ @@ -1155,8 +1140,6 @@ static int __init topology_init(void) { int cpu, r; - register_nodes(); - for_each_possible_cpu(cpu) { struct cpu *c = &per_cpu(cpu_devices, cpu); --- a/arch/riscv/kernel/setup.c~drivers-base-node-consolidate-node-device-subsystem-initialization-in-node_dev_init +++ a/arch/riscv/kernel/setup.c @@ -301,9 +301,6 @@ static int __init topology_init(void) { int i, ret; - for_each_online_node(i) - register_one_node(i); - for_each_possible_cpu(i) { struct cpu *cpu = &per_cpu(cpu_devices, i); --- a/arch/s390/kernel/numa.c~drivers-base-node-consolidate-node-device-subsystem-initialization-in-node_dev_init +++ a/arch/s390/kernel/numa.c @@ -33,10 +33,3 @@ void __init numa_setup(void) NODE_DATA(0)->node_spanned_pages = memblock_end_of_DRAM() >> PAGE_SHIFT; NODE_DATA(0)->node_id = 0; } - -static int __init numa_init_late(void) -{ - register_one_node(0); - return 0; -} -arch_initcall(numa_init_late); --- a/arch/sh/kernel/topology.c~drivers-base-node-consolidate-node-device-subsystem-initialization-in-node_dev_init +++ a/arch/sh/kernel/topology.c @@ -46,11 +46,6 @@ static int __init topology_init(void) { int i, ret; -#ifdef CONFIG_NUMA - for_each_online_node(i) - register_one_node(i); -#endif - for_each_present_cpu(i) { struct cpu *c = &per_cpu(cpu_devices, i); --- a/arch/sparc/kernel/sysfs.c~drivers-base-node-consolidate-node-device-subsystem-initialization-in-node_dev_init +++ a/arch/sparc/kernel/sysfs.c @@ -244,22 +244,10 @@ static void __init check_mmu_stats(void) mmu_stats_supported = 1; } -static void register_nodes(void) -{ -#ifdef CONFIG_NUMA - int i; - - for (i = 0; i < MAX_NUMNODES; i++) - register_one_node(i); -#endif -} - static int __init topology_init(void) { int cpu, ret; - register_nodes(); - check_mmu_stats(); for_each_possible_cpu(cpu) { --- a/arch/x86/kernel/topology.c~drivers-base-node-consolidate-node-device-subsystem-initialization-in-node_dev_init +++ a/arch/x86/kernel/topology.c @@ -154,11 +154,6 @@ static int __init topology_init(void) { int i; -#ifdef CONFIG_NUMA - for_each_online_node(i) - register_one_node(i); -#endif - for_each_present_cpu(i) arch_register_cpu(i); --- a/drivers/base/init.c~drivers-base-node-consolidate-node-device-subsystem-initialization-in-node_dev_init +++ a/drivers/base/init.c @@ -35,5 +35,6 @@ void __init driver_init(void) auxiliary_bus_init(); cpu_dev_init(); memory_dev_init(); + node_dev_init(); container_dev_init(); } --- a/drivers/base/node.c~drivers-base-node-consolidate-node-device-subsystem-initialization-in-node_dev_init +++ a/drivers/base/node.c @@ -1065,26 +1065,30 @@ static const struct attribute_group *cpu }; #define NODE_CALLBACK_PRI 2 /* lower than SLAB */ -static int __init register_node_type(void) +void __init node_dev_init(void) { - int ret; + static struct notifier_block node_memory_callback_nb = { + .notifier_call = node_memory_callback, + .priority = NODE_CALLBACK_PRI, + }; + int ret, i; BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES); BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES); ret = subsys_system_register(&node_subsys, cpu_root_attr_groups); - if (!ret) { - static struct notifier_block node_memory_callback_nb = { - .notifier_call = node_memory_callback, - .priority = NODE_CALLBACK_PRI, - }; - register_hotmemory_notifier(&node_memory_callback_nb); - } + if (ret) + panic("%s() failed to register subsystem: %d\n", __func__, ret); + + register_hotmemory_notifier(&node_memory_callback_nb); /* - * Note: we're not going to unregister the node class if we fail - * to register the node state class attribute files. + * Create all node devices, which will properly link the node + * to applicable memory block devices and already created cpu devices. */ - return ret; + for_each_online_node(i) { + ret = register_one_node(i); + if (ret) + panic("%s() failed to add node: %d\n", __func__, ret); + } } -postcore_initcall(register_node_type); --- a/include/linux/node.h~drivers-base-node-consolidate-node-device-subsystem-initialization-in-node_dev_init +++ a/include/linux/node.h @@ -112,6 +112,7 @@ static inline void link_mem_sections(int extern void unregister_node(struct node *node); #ifdef CONFIG_NUMA +extern void node_dev_init(void); /* Core of the node registration - only memory hotplug should use this */ extern int __register_one_node(int nid); @@ -149,6 +150,9 @@ extern void register_hugetlbfs_with_node node_registration_func_t unregister); #endif #else +static inline void node_dev_init(void) +{ +} static inline int __register_one_node(int nid) { return 0; _
