From: David Hildenbrand <david@xxxxxxxxxx> Subject: mm/memory_hotplug: remove memory block devices before arch_remove_memory() Let's factor out removing of memory block devices, which is only necessary for memory added via add_memory() and friends that created memory block devices. Remove the devices before calling arch_remove_memory(). This finishes factoring out memory block device handling from arch_add_memory() and arch_remove_memory(). Link: http://lkml.kernel.org/r/20190527111152.16324-10-david@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: "mike.travis@xxxxxxx" <mike.travis@xxxxxxx> Cc: Andrew Banman <andrew.banman@xxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Alex Deucher <alexander.deucher@xxxxxxx> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> Cc: Mark Brown <broonie@xxxxxxxxxx> Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxx> Cc: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> Cc: Arun KS <arunks@xxxxxxxxxxxxxx> Cc: Mathieu Malaterre <malat@xxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx> Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> Cc: Baoquan He <bhe@xxxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Chintan Pandya <cpandya@xxxxxxxxxxxxxx> Cc: Christophe Leroy <christophe.leroy@xxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx> Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Jun Yao <yaojun8558363@xxxxxxxxx> Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: Logan Gunthorpe <logang@xxxxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx> Cc: Nicholas Piggin <npiggin@xxxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Qian Cai <cai@xxxxxx> Cc: Rich Felker <dalias@xxxxxxxx> Cc: Rob Herring <robh@xxxxxxxxxx> Cc: Robin Murphy <robin.murphy@xxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Tony Luck <tony.luck@xxxxxxxxx> Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> Cc: Wei Yang <richard.weiyang@xxxxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx> Cc: Yu Zhao <yuzhao@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/base/memory.c | 37 ++++++++++++++++++------------------- drivers/base/node.c | 11 ++++++----- include/linux/memory.h | 2 +- include/linux/node.h | 6 ++---- mm/memory_hotplug.c | 5 +++-- 5 files changed, 30 insertions(+), 31 deletions(-) --- a/drivers/base/memory.c~mm-memory_hotplug-remove-memory-block-devices-before-arch_remove_memory +++ a/drivers/base/memory.c @@ -759,32 +759,31 @@ int create_memory_block_devices(unsigned return ret; } -void unregister_memory_section(struct mem_section *section) +/* + * Remove memory block devices for the given memory area. Start and size + * have to be aligned to memory block granularity. Memory block devices + * have to be offline. + */ +void remove_memory_block_devices(unsigned long start, unsigned long size) { + const int start_block_id = pfn_to_block_id(PFN_DOWN(start)); + const int end_block_id = pfn_to_block_id(PFN_DOWN(start + size)); struct memory_block *mem; + int block_id; - if (WARN_ON_ONCE(!present_section(section))) + if (WARN_ON_ONCE(!IS_ALIGNED(start, memory_block_size_bytes()) || + !IS_ALIGNED(size, memory_block_size_bytes()))) return; mutex_lock(&mem_sysfs_mutex); - - /* - * Some users of the memory hotplug do not want/need memblock to - * track all sections. Skip over those. - */ - mem = find_memory_block(section); - if (!mem) - goto out_unlock; - - unregister_mem_sect_under_nodes(mem, __section_nr(section)); - - mem->section_count--; - if (mem->section_count == 0) + for (block_id = start_block_id; block_id != end_block_id; block_id++) { + mem = find_memory_block_by_id(block_id, NULL); + if (WARN_ON_ONCE(!mem)) + continue; + mem->section_count = 0; + unregister_memory_block_under_nodes(mem); unregister_memory(mem); - else - put_device(&mem->dev); - -out_unlock: + } mutex_unlock(&mem_sysfs_mutex); } --- a/drivers/base/node.c~mm-memory_hotplug-remove-memory-block-devices-before-arch_remove_memory +++ a/drivers/base/node.c @@ -802,9 +802,10 @@ int register_mem_sect_under_node(struct return 0; } -/* unregister memory section under all nodes that it spans */ -int unregister_mem_sect_under_nodes(struct memory_block *mem_blk, - unsigned long phys_index) +/* + * Unregister memory block device under all nodes that it spans. + */ +int unregister_memory_block_under_nodes(struct memory_block *mem_blk) { NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL); unsigned long pfn, sect_start_pfn, sect_end_pfn; @@ -817,8 +818,8 @@ int unregister_mem_sect_under_nodes(stru return -ENOMEM; nodes_clear(*unlinked_nodes); - sect_start_pfn = section_nr_to_pfn(phys_index); - sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1; + sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr); + sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr); for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) { int nid; --- a/include/linux/memory.h~mm-memory_hotplug-remove-memory-block-devices-before-arch_remove_memory +++ a/include/linux/memory.h @@ -112,7 +112,7 @@ extern void unregister_memory_notifier(s extern int register_memory_isolate_notifier(struct notifier_block *nb); extern void unregister_memory_isolate_notifier(struct notifier_block *nb); int create_memory_block_devices(unsigned long start, unsigned long size); -extern void unregister_memory_section(struct mem_section *); +void remove_memory_block_devices(unsigned long start, unsigned long size); extern int memory_dev_init(void); extern int memory_notify(unsigned long val, void *v); extern int memory_isolate_notify(unsigned long val, void *v); --- a/include/linux/node.h~mm-memory_hotplug-remove-memory-block-devices-before-arch_remove_memory +++ a/include/linux/node.h @@ -139,8 +139,7 @@ extern int register_cpu_under_node(unsig extern int unregister_cpu_under_node(unsigned int cpu, unsigned int nid); extern int register_mem_sect_under_node(struct memory_block *mem_blk, void *arg); -extern int unregister_mem_sect_under_nodes(struct memory_block *mem_blk, - unsigned long phys_index); +extern int unregister_memory_block_under_nodes(struct memory_block *mem_blk); extern int register_memory_node_under_compute_node(unsigned int mem_nid, unsigned int cpu_nid, @@ -176,8 +175,7 @@ static inline int register_mem_sect_unde { return 0; } -static inline int unregister_mem_sect_under_nodes(struct memory_block *mem_blk, - unsigned long phys_index) +static inline int unregister_memory_block_under_nodes(struct memory_block *mem_blk) { return 0; } --- a/mm/memory_hotplug.c~mm-memory_hotplug-remove-memory-block-devices-before-arch_remove_memory +++ a/mm/memory_hotplug.c @@ -520,8 +520,6 @@ static void __remove_section(struct zone if (WARN_ON_ONCE(!valid_section(ms))) return; - unregister_memory_section(ms); - scn_nr = __section_nr(ms); start_pfn = section_nr_to_pfn((unsigned long)scn_nr); __remove_zone(zone, start_pfn); @@ -1834,6 +1832,9 @@ static int __ref try_remove_memory(int n memblock_free(start, size); memblock_remove(start, size); + /* remove memory block devices before removing memory */ + remove_memory_block_devices(start, size); + arch_remove_memory(nid, start, size, NULL); __release_memory_resource(start, size); _
