diff options
Diffstat (limited to 'mm/percpu.c')
| -rw-r--r-- | mm/percpu.c | 111 |
1 files changed, 56 insertions, 55 deletions
diff --git a/mm/percpu.c b/mm/percpu.c index 105f171aad29..b403d7c02c67 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -1,5 +1,5 @@ /* - * linux/mm/percpu.c - percpu memory allocator + * mm/percpu.c - percpu memory allocator * * Copyright (C) 2009 SUSE Linux Products GmbH * Copyright (C) 2009 Tejun Heo <tj@kernel.org> @@ -7,14 +7,13 @@ * This file is released under the GPLv2. * * This is percpu allocator which can handle both static and dynamic - * areas. Percpu areas are allocated in chunks in vmalloc area. Each - * chunk is consisted of boot-time determined number of units and the - * first chunk is used for static percpu variables in the kernel image + * areas. Percpu areas are allocated in chunks. Each chunk is + * consisted of boot-time determined number of units and the first + * chunk is used for static percpu variables in the kernel image * (special boot time alloc/init handling necessary as these areas * need to be brought up before allocation services are running). * Unit grows as necessary and all units grow or shrink in unison. - * When a chunk is filled up, another chunk is allocated. ie. in - * vmalloc area + * When a chunk is filled up, another chunk is allocated. * * c0 c1 c2 * ------------------- ------------------- ------------ @@ -99,7 +98,7 @@ struct pcpu_chunk { int map_used; /* # of map entries used */ int map_alloc; /* # of map entries allocated */ int *map; /* allocation map */ - struct vm_struct **vms; /* mapped vmalloc regions */ + void *data; /* chunk data */ bool immutable; /* no [de]population allowed */ unsigned long populated[]; /* populated bitmap */ }; @@ -213,13 +212,25 @@ static int pcpu_chunk_slot(const struct pcpu_chunk *chunk) return pcpu_size_to_slot(chunk->free_size); } -static int pcpu_page_idx(unsigned int cpu, int page_idx) +/* set the pointer to a chunk in a page struct */ +static void pcpu_set_page_chunk(struct page *page, struct pcpu_chunk *pcpu) +{ + page->index = (unsigned long)pcpu; +} + +/* obtain pointer to a chunk from a page struct */ +static struct pcpu_chunk *pcpu_get_page_chunk(struct page *page) +{ + return (struct pcpu_chunk *)page->index; +} + +static int __maybe_unused pcpu_page_idx(unsigned int cpu, int page_idx) { return pcpu_unit_map[cpu] * pcpu_unit_pages + page_idx; } -static unsigned long pcpu_chunk_addr(struct pcpu_chunk *chunk, - unsigned int cpu, int page_idx) +static unsigned long __maybe_unused pcpu_chunk_addr(struct pcpu_chunk *chunk, + unsigned int cpu, int page_idx) { return (unsigned long)chunk->base_addr + pcpu_unit_offsets[cpu] + (page_idx << PAGE_SHIFT); @@ -234,25 +245,15 @@ static struct page *pcpu_chunk_page(struct pcpu_chunk *chunk, return vmalloc_to_page((void *)pcpu_chunk_addr(chunk, cpu, page_idx)); } -/* set the pointer to a chunk in a page struct */ -static void pcpu_set_page_chunk(struct page *page, struct pcpu_chunk *pcpu) -{ - page->index = (unsigned long)pcpu; -} - -/* obtain pointer to a chunk from a page struct */ -static struct pcpu_chunk *pcpu_get_page_chunk(struct page *page) -{ - return (struct pcpu_chunk *)page->index; -} - -static void pcpu_next_unpop(struct pcpu_chunk *chunk, int *rs, int *re, int end) +static void __maybe_unused pcpu_next_unpop(struct pcpu_chunk *chunk, + int *rs, int *re, int end) { *rs = find_next_zero_bit(chunk->populated, end, *rs); *re = find_next_bit(chunk->populated, end, *rs + 1); } -static void pcpu_next_pop(struct pcpu_chunk *chunk, int *rs, int *re, int end) +static void __maybe_unused pcpu_next_pop(struct pcpu_chunk *chunk, + int *rs, int *re, int end) { *rs = find_next_bit(chunk->populated, end, *rs); *re = find_next_zero_bit(chunk->populated, end, *rs + 1); @@ -341,34 +342,6 @@ static void pcpu_chunk_relocate(struct pcpu_chunk *chunk, int oslot) } /** - * pcpu_chunk_addr_search - determine chunk containing specified address - * @addr: address for which the chunk needs to be determined. - * - * RETURNS: - * The address of the found chunk. - */ -static struct pcpu_chunk *pcpu_chunk_addr_search(void *addr) -{ - /* is it in the first chunk? */ - if (pcpu_addr_in_first_chunk(addr)) { - /* is it in the reserved area? */ - if (pcpu_addr_in_reserved_chunk(addr)) - return pcpu_reserved_chunk; - return pcpu_first_chunk; - } - - /* - * The address is relative to unit0 which might be unused and - * thus unmapped. Offset the address to the unit space of the - * current processor before looking it up in the vmalloc - * space. Note that any possible cpu id can be used here, so - * there's no need to worry about preemption or cpu hotplug. - */ - addr += pcpu_unit_offsets[raw_smp_processor_id()]; - return pcpu_get_page_chunk(vmalloc_to_page(addr)); -} - -/** * pcpu_need_to_extend - determine whether chunk area map needs to be extended * @chunk: chunk of interest * @@ -1062,8 +1035,8 @@ err_free: static void pcpu_destroy_chunk(struct pcpu_chunk *chunk) { - if (chunk && chunk->vms) - pcpu_free_vm_areas(chunk->vms, pcpu_nr_groups); + if (chunk && chunk->data) + pcpu_free_vm_areas(chunk->data, pcpu_nr_groups); pcpu_free_chunk(chunk); } @@ -1083,12 +1056,40 @@ static struct pcpu_chunk *pcpu_create_chunk(void) return NULL; } - chunk->vms = vms; + chunk->data = vms; chunk->base_addr = vms[0]->addr - pcpu_group_offsets[0]; return chunk; } /** + * pcpu_chunk_addr_search - determine chunk containing specified address + * @addr: address for which the chunk needs to be determined. + * + * RETURNS: + * The address of the found chunk. + */ +static struct pcpu_chunk *pcpu_chunk_addr_search(void *addr) +{ + /* is it in the first chunk? */ + if (pcpu_addr_in_first_chunk(addr)) { + /* is it in the reserved area? */ + if (pcpu_addr_in_reserved_chunk(addr)) + return pcpu_reserved_chunk; + return pcpu_first_chunk; + } + + /* + * The address is relative to unit0 which might be unused and + * thus unmapped. Offset the address to the unit space of the + * current processor before looking it up in the vmalloc + * space. Note that any possible cpu id can be used here, so + * there's no need to worry about preemption or cpu hotplug. + */ + addr += pcpu_unit_offsets[raw_smp_processor_id()]; + return pcpu_get_page_chunk(vmalloc_to_page(addr)); +} + +/** * pcpu_alloc - the percpu allocator * @size: size of area to allocate in bytes * @align: alignment of area (max PAGE_SIZE) |