In preparation for allowing all ZONE_DEVICE page init to happen in the background, enable multiple vmemmap_populate_hugepages() invocations to run in parallel. To date the big memory-hotplug lock has been used to serialize changes to the linear map and vmemmap. Finer grained locking is needed to prevent 2 parallel invocations of vmemmap_populate_hugepages() colliding. Given that populating vmemmap has architecture specific implications this new asynchronous support is only added for the x86_64 arch_add_memory(), all other implementations indicate no support for async operations by returning -EWOULDBLOCK. Cc: Tony Luck <tony.luck@xxxxxxxxx> Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx> Cc: Rich Felker <dalias@xxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: <x86@xxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Daniel Jordan <daniel.m.jordan@xxxxxxxxxx> Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> --- arch/ia64/mm/init.c | 5 ++- arch/powerpc/mm/mem.c | 5 ++- arch/s390/mm/init.c | 8 +++-- arch/sh/mm/init.c | 5 ++- arch/x86/mm/init_32.c | 8 +++-- arch/x86/mm/init_64.c | 27 ++++++++++------ drivers/nvdimm/pfn_devs.c | 1 + include/linux/memmap_async.h | 53 +++++++++++++++++++++++++++++++ include/linux/memory_hotplug.h | 15 ++++++--- include/linux/memremap.h | 2 + include/linux/mm.h | 6 ++- kernel/memremap.c | 4 +- mm/memory_hotplug.c | 69 ++++++++++++++++++++++++++++++---------- mm/page_alloc.c | 3 ++ mm/sparse-vmemmap.c | 56 +++++++++++++++++++++++++------- 15 files changed, 209 insertions(+), 58 deletions(-) create mode 100644 include/linux/memmap_async.h diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c index 18278b448530..d331488dd76f 100644 --- a/arch/ia64/mm/init.c +++ b/arch/ia64/mm/init.c @@ -649,12 +649,15 @@ mem_init (void) #ifdef CONFIG_MEMORY_HOTPLUG int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap, - bool want_memblock) + bool want_memblock, struct memmap_async_state *async) { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; int ret; + if (async) + return -EWOULDBLOCK; + ret = __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock); if (ret) printk("%s: Problem encountered in __add_pages() as ret=%d\n", diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index 5c8530d0c611..3205a361e37a 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -118,12 +118,15 @@ int __weak remove_section_mapping(unsigned long start, unsigned long end) } int __meminit arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap, - bool want_memblock) + bool want_memblock, struct memmap_async_state *async) { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; int rc; + if (async) + return -EWOULDBLOCK; + resize_hpt_for_hotplug(memblock_phys_mem_size()); start = (unsigned long)__va(start); diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index 3fa3e5323612..ee87085a3a58 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -223,17 +223,21 @@ device_initcall(s390_cma_mem_init); #endif /* CONFIG_CMA */ int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap, - bool want_memblock) + bool want_memblock, struct memmap_async_state *async) { unsigned long start_pfn = PFN_DOWN(start); unsigned long size_pages = PFN_DOWN(size); int rc; + if (async) + return -EWOULDBLOCK; + rc = vmem_add_mapping(start, size); if (rc) return rc; - rc = __add_pages(nid, start_pfn, size_pages, altmap, want_memblock); + rc = __add_pages(nid, start_pfn, size_pages, altmap, want_memblock, + async); if (rc) vmem_remove_mapping(start, size); return rc; diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c index 4034035fbede..534303de3ec2 100644 --- a/arch/sh/mm/init.c +++ b/arch/sh/mm/init.c @@ -430,12 +430,15 @@ void free_initrd_mem(unsigned long start, unsigned long end) #ifdef CONFIG_MEMORY_HOTPLUG int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap, - bool want_memblock) + bool want_memblock, struct memmap_async_state *async) { unsigned long start_pfn = PFN_DOWN(start); unsigned long nr_pages = size >> PAGE_SHIFT; int ret; + if (async) + return -EWOULDBLOCK; + /* We only have ZONE_NORMAL, so this is easy.. */ ret = __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock); if (unlikely(ret)) diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 979e0a02cbe1..1be538746010 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -852,12 +852,16 @@ void __init mem_init(void) #ifdef CONFIG_MEMORY_HOTPLUG int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap, - bool want_memblock) + bool want_memblock, struct memmap_async_state *async) { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; - return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock); + if (async) + return -EWOULDBLOCK; + + return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock, + async); } #ifdef CONFIG_MEMORY_HOTREMOVE diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index a688617c727e..40bd9ba052fe 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -784,11 +784,13 @@ static void update_end_of_memory_vars(u64 start, u64 size) } int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, - struct vmem_altmap *altmap, bool want_memblock) + struct vmem_altmap *altmap, bool want_memblock, + struct memmap_async_state *async) { int ret; - ret = __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock); + ret = __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock, + async); WARN_ON_ONCE(ret); /* update max_pfn, max_low_pfn and high_memory */ @@ -799,14 +801,15 @@ int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, } int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap, - bool want_memblock) + bool want_memblock, struct memmap_async_state *async) { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; init_memory_mapping(start, start + size); - return add_pages(nid, start_pfn, nr_pages, altmap, want_memblock); + return add_pages(nid, start_pfn, nr_pages, altmap, want_memblock, + async); } #define PAGE_INUSE 0xFD @@ -1412,26 +1415,30 @@ static int __meminit vmemmap_populate_hugepages(unsigned long start, { unsigned long addr; unsigned long next; - pgd_t *pgd; - p4d_t *p4d; - pud_t *pud; + pgd_t *pgd = NULL; + p4d_t *p4d = NULL; + pud_t *pud = NULL; pmd_t *pmd; for (addr = start; addr < end; addr = next) { next = pmd_addr_end(addr, end); - pgd = vmemmap_pgd_populate(addr, node); + pgd = vmemmap_pgd_populate(addr, node, pgd); if (!pgd) return -ENOMEM; - p4d = vmemmap_p4d_populate(pgd, addr, node); + p4d = vmemmap_p4d_populate(pgd, addr, node, p4d); if (!p4d) return -ENOMEM; - pud = vmemmap_pud_populate(p4d, addr, node); + pud = vmemmap_pud_populate(p4d, addr, node, pud); if (!pud) return -ENOMEM; + /* + * No lock required here as sections do not collide + * below the pud level. + */ pmd = pmd_offset(pud, addr); if (pmd_none(*pmd)) { void *p; diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c index 3f7ad5bc443e..147c62e2ef2b 100644 --- a/drivers/nvdimm/pfn_devs.c +++ b/drivers/nvdimm/pfn_devs.c @@ -577,6 +577,7 @@ static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) memcpy(altmap, &__altmap, sizeof(*altmap)); altmap->free = PHYS_PFN(offset - SZ_8K); altmap->alloc = 0; + spin_lock_init(&altmap->lock); pgmap->altmap_valid = true; } else return -ENXIO; diff --git a/include/linux/memmap_async.h b/include/linux/memmap_async.h new file mode 100644 index 000000000000..c641b80a3c24 --- /dev/null +++ b/include/linux/memmap_async.h @@ -0,0 +1,53 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __LINUX_MEMMAP_ASYNC_H +#define __LINUX_MEMMAP_ASYNC_H +#include <linux/async.h> + +struct vmem_altmap; + +/** + * struct memmap_init_env - common global data for all async memmap operations + * @altmap: set-aside / alternative memory for allocating the memmap + * @want_memblock: typical memory (!ZONE_DEVICE) is onlined via memblock + * @nid: home node for the memory range + */ +struct memmap_init_env { + struct vmem_altmap *altmap; + bool want_memblock; + int nid; +}; + +/** + * struct memmap_init_memmap - parameters for async memmap page table init + * @env: common arguments for all async memmap operations + * @cookie: async thread id for follow on threads to sync page table init + * @start_sec: first memory section in the arch_add_memory() range + * @end_sec: last memory section in the arch_add_memory() range + * @result: did page table init succeed? + */ +struct memmap_init_memmap { + struct memmap_init_env *env; + async_cookie_t cookie; + int start_sec; + int end_sec; + int result; +}; + +/** + * struct memmap_async_state - support and track async memmap operations + * @env: storage for common memmap init parameters + * @memmap: storage for background page-table setup operations + * + * An instance of this object is passed to the memory hotplug + * infrastructure to indicate that memory hotplug work should be + * delegated to background threads. The caller takes responsibility for + * waiting for those threads to complete before calling pfn_to_page() on + * any new page. + */ +struct memmap_async_state { + struct memmap_init_env env; + struct memmap_init_memmap memmap; +}; + +extern struct async_domain memmap_init_domain; +#endif /* __LINUX_MEMMAP_ASYNC_H */ diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index e60085b2824d..7565b2675863 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -15,6 +15,7 @@ struct memory_block; struct resource; struct vmem_altmap; struct dev_pagemap; +struct memmap_async_state; #ifdef CONFIG_MEMORY_HOTPLUG /* @@ -116,18 +117,21 @@ extern int __remove_pages(struct zone *zone, unsigned long start_pfn, /* reasonably generic interface to expand the physical pages */ extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, - struct vmem_altmap *altmap, bool want_memblock); + struct vmem_altmap *altmap, bool want_memblock, + struct memmap_async_state *async); #ifndef CONFIG_ARCH_HAS_ADD_PAGES static inline int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, struct vmem_altmap *altmap, - bool want_memblock) + bool want_memblock, struct memmap_async_state *async) { - return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock); + return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock, + async); } #else /* ARCH_HAS_ADD_PAGES */ int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, - struct vmem_altmap *altmap, bool want_memblock); + struct vmem_altmap *altmap, bool want_memblock, + struct memmap_async_state *async); #endif /* ARCH_HAS_ADD_PAGES */ #ifdef CONFIG_NUMA @@ -325,7 +329,8 @@ extern int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn, extern int add_memory(int nid, u64 start, u64 size); extern int add_memory_resource(int nid, struct resource *resource, bool online); extern int arch_add_memory(int nid, u64 start, u64 size, - struct vmem_altmap *altmap, bool want_memblock); + struct vmem_altmap *altmap, bool want_memblock, + struct memmap_async_state *async); extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn, unsigned long nr_pages, struct dev_pagemap *pgmap); extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages); diff --git a/include/linux/memremap.h b/include/linux/memremap.h index 71f5e7c7dfb9..bfdc7363b13b 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -16,6 +16,7 @@ struct device; * @free: free pages set aside in the mapping for memmap storage * @align: pages reserved to meet allocation alignments * @alloc: track pages consumed, private to vmemmap_populate() + * @lock: enable parallel allocations */ struct vmem_altmap { const unsigned long base_pfn; @@ -23,6 +24,7 @@ struct vmem_altmap { unsigned long free; unsigned long align; unsigned long alloc; + spinlock_t lock; }; /* diff --git a/include/linux/mm.h b/include/linux/mm.h index 319d01372efa..0fac83ff21c5 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2654,9 +2654,9 @@ void sparse_mem_maps_populate_node(struct page **map_map, struct page *sparse_mem_map_populate(unsigned long pnum, int nid, struct vmem_altmap *altmap); -pgd_t *vmemmap_pgd_populate(unsigned long addr, int node); -p4d_t *vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node); -pud_t *vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node); +pgd_t *vmemmap_pgd_populate(unsigned long addr, int node, pgd_t *); +p4d_t *vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node, p4d_t *); +pud_t *vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node, pud_t *); pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node); pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node); void *vmemmap_alloc_block(unsigned long size, int node); diff --git a/kernel/memremap.c b/kernel/memremap.c index 58327259420d..b861fe909932 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -235,12 +235,12 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap, */ if (pgmap->type == MEMORY_DEVICE_PRIVATE) { error = add_pages(nid, align_start >> PAGE_SHIFT, - align_size >> PAGE_SHIFT, NULL, false); + align_size >> PAGE_SHIFT, NULL, false, NULL); } else { struct zone *zone; error = arch_add_memory(nid, align_start, align_size, altmap, - false); + false, NULL); zone = &NODE_DATA(nid)->node_zones[ZONE_DEVICE]; if (!error) move_pfn_range_to_zone(zone, align_start >> PAGE_SHIFT, diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index aae4e6cc65e9..18f8e2c49089 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -34,6 +34,8 @@ #include <linux/hugetlb.h> #include <linux/memblock.h> #include <linux/bootmem.h> +#include <linux/memmap_async.h> +#include <linux/async.h> #include <linux/compaction.h> #include <asm/tlbflush.h> @@ -264,6 +266,32 @@ static int __meminit __add_section(int nid, unsigned long phys_start_pfn, return hotplug_memory_register(nid, __pfn_to_section(phys_start_pfn)); } +static void __ref section_init_async(void *data, async_cookie_t cookie) +{ + unsigned long i; + struct memmap_init_memmap *args = data; + struct memmap_init_env *env = args->env; + int start_sec = args->start_sec, end_sec = args->end_sec, err; + + args->result = 0; + for (i = start_sec; i <= end_sec; i++) { + err = __add_section(env->nid, section_nr_to_pfn(i), env->altmap, + env->want_memblock); + + /* + * EEXIST is finally dealt with by ioresource collision + * check. see add_memory() => register_memory_resource() + * Warning will be printed if there is collision. + */ + if (err && (err != -EEXIST)) { + args->result = err; + break; + } + args->result = 0; + cond_resched(); + } +} + /* * Reasonably generic function for adding memory. It is * expected that archs that support memory hotplug will @@ -272,11 +300,12 @@ static int __meminit __add_section(int nid, unsigned long phys_start_pfn, */ int __ref __add_pages(int nid, unsigned long phys_start_pfn, unsigned long nr_pages, struct vmem_altmap *altmap, - bool want_memblock) + bool want_memblock, struct memmap_async_state *async) { - unsigned long i; int err = 0; int start_sec, end_sec; + struct memmap_init_env _env, *env; + struct memmap_init_memmap _args, *args; /* during initialize mem_map, align hot-added range to section */ start_sec = pfn_to_section_nr(phys_start_pfn); @@ -289,28 +318,32 @@ int __ref __add_pages(int nid, unsigned long phys_start_pfn, if (altmap->base_pfn != phys_start_pfn || vmem_altmap_offset(altmap) > nr_pages) { pr_warn_once("memory add fail, invalid altmap\n"); - err = -EINVAL; - goto out; + return -EINVAL; } altmap->alloc = 0; } - for (i = start_sec; i <= end_sec; i++) { - err = __add_section(nid, section_nr_to_pfn(i), altmap, - want_memblock); + env = async ? &async->env : &_env; + args = async ? &async->memmap : &_args; - /* - * EEXIST is finally dealt with by ioresource collision - * check. see add_memory() => register_memory_resource() - * Warning will be printed if there is collision. - */ - if (err && (err != -EEXIST)) - break; - err = 0; - cond_resched(); + env->nid = nid; + env->altmap = altmap; + env->want_memblock = want_memblock; + + args->env = env; + args->end_sec = end_sec; + args->start_sec = start_sec; + + if (async) + args->cookie = async_schedule_domain(section_init_async, args, + &memmap_init_domain); + else { + /* call the 'async' routine synchronously */ + section_init_async(args, 0); + err = args->result; } + vmemmap_populate_print_last(); -out: return err; } @@ -1135,7 +1168,7 @@ int __ref add_memory_resource(int nid, struct resource *res, bool online) } /* call arch's memory hotadd */ - ret = arch_add_memory(nid, start, size, NULL, true); + ret = arch_add_memory(nid, start, size, NULL, true, NULL); if (ret < 0) goto error; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 545a5860cce7..f83682ef006e 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -66,6 +66,7 @@ #include <linux/memcontrol.h> #include <linux/ftrace.h> #include <linux/lockdep.h> +#include <linux/async.h> #include <linux/nmi.h> #include <asm/sections.h> @@ -5452,6 +5453,8 @@ void __ref build_all_zonelists(pg_data_t *pgdat) #endif } +ASYNC_DOMAIN_EXCLUSIVE(memmap_init_domain); + /* * Initially all pages are reserved - free ones are freed * up by free_all_bootmem() once the early boot process is diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c index bd0276d5f66b..9cdd82fb595d 100644 --- a/mm/sparse-vmemmap.c +++ b/mm/sparse-vmemmap.c @@ -93,6 +93,7 @@ void * __meminit vmemmap_alloc_block_buf(unsigned long size, int node) static unsigned long __meminit vmem_altmap_next_pfn(struct vmem_altmap *altmap) { + lockdep_assert_held(&altmap->lock); return altmap->base_pfn + altmap->reserve + altmap->alloc + altmap->align; } @@ -101,6 +102,7 @@ static unsigned long __meminit vmem_altmap_nr_free(struct vmem_altmap *altmap) { unsigned long allocated = altmap->alloc + altmap->align; + lockdep_assert_held(&altmap->lock); if (altmap->free > allocated) return altmap->free - allocated; return 0; @@ -124,16 +126,20 @@ void * __meminit altmap_alloc_block_buf(unsigned long size, return NULL; } + spin_lock(&altmap->lock); pfn = vmem_altmap_next_pfn(altmap); nr_pfns = size >> PAGE_SHIFT; nr_align = 1UL << find_first_bit(&nr_pfns, BITS_PER_LONG); nr_align = ALIGN(pfn, nr_align) - pfn; - if (nr_pfns + nr_align > vmem_altmap_nr_free(altmap)) + if (nr_pfns + nr_align > vmem_altmap_nr_free(altmap)) { + spin_unlock(&altmap->lock); return NULL; + } altmap->alloc += nr_pfns; altmap->align += nr_align; pfn += nr_align; + spin_unlock(&altmap->lock); pr_debug("%s: pfn: %#lx alloc: %ld align: %ld nr: %#lx\n", __func__, pfn, altmap->alloc, altmap->align, nr_pfns); @@ -188,39 +194,63 @@ pmd_t * __meminit vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node) return pmd; } -pud_t * __meminit vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node) +static DEFINE_MUTEX(vmemmap_pgd_lock); +static DEFINE_MUTEX(vmemmap_p4d_lock); +static DEFINE_MUTEX(vmemmap_pud_lock); + +pud_t * __meminit vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node, + pud_t *pud) { - pud_t *pud = pud_offset(p4d, addr); + pud_t *new = pud_offset(p4d, addr); + + if (new == pud) + return pud; + pud = new; + mutex_lock(&vmemmap_pud_lock); if (pud_none(*pud)) { void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node); if (!p) return NULL; pud_populate(&init_mm, pud, p); } + mutex_unlock(&vmemmap_pud_lock); return pud; } -p4d_t * __meminit vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node) +p4d_t * __meminit vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node, + p4d_t * p4d) { - p4d_t *p4d = p4d_offset(pgd, addr); + p4d_t *new = p4d_offset(pgd, addr); + + if (new == p4d) + return p4d; + p4d = new; + mutex_lock(&vmemmap_p4d_lock); if (p4d_none(*p4d)) { void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node); if (!p) return NULL; p4d_populate(&init_mm, p4d, p); } + mutex_unlock(&vmemmap_p4d_lock); return p4d; } -pgd_t * __meminit vmemmap_pgd_populate(unsigned long addr, int node) +pgd_t * __meminit vmemmap_pgd_populate(unsigned long addr, int node, pgd_t *pgd) { - pgd_t *pgd = pgd_offset_k(addr); + pgd_t *new = pgd_offset_k(addr); + + if (new == pgd) + return pgd; + pgd = new; + mutex_lock(&vmemmap_pgd_lock); if (pgd_none(*pgd)) { void *p = vmemmap_alloc_block_zero(PAGE_SIZE, node); if (!p) return NULL; pgd_populate(&init_mm, pgd, p); } + mutex_unlock(&vmemmap_pgd_lock); return pgd; } @@ -228,20 +258,20 @@ int __meminit vmemmap_populate_basepages(unsigned long start, unsigned long end, int node) { unsigned long addr = start; - pgd_t *pgd; - p4d_t *p4d; - pud_t *pud; + pgd_t *pgd = NULL; + p4d_t *p4d = NULL; + pud_t *pud = NULL; pmd_t *pmd; pte_t *pte; for (; addr < end; addr += PAGE_SIZE) { - pgd = vmemmap_pgd_populate(addr, node); + pgd = vmemmap_pgd_populate(addr, node, pgd); if (!pgd) return -ENOMEM; - p4d = vmemmap_p4d_populate(pgd, addr, node); + p4d = vmemmap_p4d_populate(pgd, addr, node, p4d); if (!p4d) return -ENOMEM; - pud = vmemmap_pud_populate(p4d, addr, node); + pud = vmemmap_pud_populate(p4d, addr, node, pud); if (!pud) return -ENOMEM; pmd = vmemmap_pmd_populate(pud, addr, node);