diff options
Diffstat (limited to 'mm/percpu.c')
| -rw-r--r-- | mm/percpu.c | 694 |
1 files changed, 185 insertions, 509 deletions
diff --git a/mm/percpu.c b/mm/percpu.c index 6e09741ddc62..e61dc2cc5873 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 */ }; @@ -177,6 +176,21 @@ static struct list_head *pcpu_slot __read_mostly; /* chunk list slots */ static void pcpu_reclaim(struct work_struct *work); static DECLARE_WORK(pcpu_reclaim_work, pcpu_reclaim); +static bool pcpu_addr_in_first_chunk(void *addr) +{ + void *first_start = pcpu_first_chunk->base_addr; + + return addr >= first_start && addr < first_start + pcpu_unit_size; +} + +static bool pcpu_addr_in_reserved_chunk(void *addr) +{ + void *first_start = pcpu_first_chunk->base_addr; + + return addr >= first_start && + addr < first_start + pcpu_reserved_chunk_limit; +} + static int __pcpu_size_to_slot(int size) { int highbit = fls(size); /* size is in bytes */ @@ -198,27 +212,6 @@ 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) -{ - 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) -{ - return (unsigned long)chunk->base_addr + pcpu_unit_offsets[cpu] + - (page_idx << PAGE_SHIFT); -} - -static struct page *pcpu_chunk_page(struct pcpu_chunk *chunk, - unsigned int cpu, int page_idx) -{ - /* must not be used on pre-mapped chunk */ - WARN_ON(chunk->immutable); - - 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) { @@ -231,13 +224,27 @@ 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 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) +{ + return (unsigned long)chunk->base_addr + pcpu_unit_offsets[cpu] + + (page_idx << PAGE_SHIFT); +} + +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); @@ -275,6 +282,9 @@ static void pcpu_next_pop(struct pcpu_chunk *chunk, int *rs, int *re, int end) */ static void *pcpu_mem_alloc(size_t size) { + if (WARN_ON_ONCE(!slab_is_available())) + return NULL; + if (size <= PAGE_SIZE) return kzalloc(size, GFP_KERNEL); else { @@ -326,36 +336,6 @@ 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) -{ - void *first_start = pcpu_first_chunk->base_addr; - - /* is it in the first chunk? */ - if (addr >= first_start && addr < first_start + pcpu_unit_size) { - /* is it in the reserved area? */ - if (addr < first_start + pcpu_reserved_chunk_limit) - 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 * @@ -415,13 +395,6 @@ static int pcpu_extend_area_map(struct pcpu_chunk *chunk, int new_alloc) old_size = chunk->map_alloc * sizeof(chunk->map[0]); memcpy(new, chunk->map, old_size); - /* - * map_alloc < PCPU_DFL_MAP_ALLOC indicates that the chunk is - * one of the first chunks and still using static map. - */ - if (chunk->map_alloc >= PCPU_DFL_MAP_ALLOC) - old = chunk->map; - chunk->map_alloc = new_alloc; chunk->map = new; new = NULL; @@ -623,434 +596,92 @@ static void pcpu_free_area(struct pcpu_chunk *chunk, int freeme) pcpu_chunk_relocate(chunk, oslot); } -/** - * pcpu_get_pages_and_bitmap - get temp pages array and bitmap - * @chunk: chunk of interest - * @bitmapp: output parameter for bitmap - * @may_alloc: may allocate the array - * - * Returns pointer to array of pointers to struct page and bitmap, - * both of which can be indexed with pcpu_page_idx(). The returned - * array is cleared to zero and *@bitmapp is copied from - * @chunk->populated. Note that there is only one array and bitmap - * and access exclusion is the caller's responsibility. - * - * CONTEXT: - * pcpu_alloc_mutex and does GFP_KERNEL allocation if @may_alloc. - * Otherwise, don't care. - * - * RETURNS: - * Pointer to temp pages array on success, NULL on failure. - */ -static struct page **pcpu_get_pages_and_bitmap(struct pcpu_chunk *chunk, - unsigned long **bitmapp, - bool may_alloc) +static struct pcpu_chunk *pcpu_alloc_chunk(void) { - static struct page **pages; - static unsigned long *bitmap; - size_t pages_size = pcpu_nr_units * pcpu_unit_pages * sizeof(pages[0]); - size_t bitmap_size = BITS_TO_LONGS(pcpu_unit_pages) * - sizeof(unsigned long); - - if (!pages || !bitmap) { - if (may_alloc && !pages) - pages = pcpu_mem_alloc(pages_size); - if (may_alloc && !bitmap) - bitmap = pcpu_mem_alloc(bitmap_size); - if (!pages || !bitmap) - return NULL; - } - - memset(pages, 0, pages_size); - bitmap_copy(bitmap, chunk->populated, pcpu_unit_pages); - - *bitmapp = bitmap; - return pages; -} - -/** - * pcpu_free_pages - free pages which were allocated for @chunk - * @chunk: chunk pages were allocated for - * @pages: array of pages to be freed, indexed by pcpu_page_idx() - * @populated: populated bitmap - * @page_start: page index of the first page to be freed - * @page_end: page index of the last page to be freed + 1 - * - * Free pages [@page_start and @page_end) in @pages for all units. - * The pages were allocated for @chunk. - */ -static void pcpu_free_pages(struct pcpu_chunk *chunk, - struct page **pages, unsigned long *populated, - int page_start, int page_end) -{ - unsigned int cpu; - int i; + struct pcpu_chunk *chunk; - for_each_possible_cpu(cpu) { - for (i = page_start; i < page_end; i++) { - struct page *page = pages[pcpu_page_idx(cpu, i)]; + chunk = pcpu_mem_alloc(pcpu_chunk_struct_size); + if (!chunk) + return NULL; - if (page) - __free_page(page); - } + chunk->map = pcpu_mem_alloc(PCPU_DFL_MAP_ALLOC * sizeof(chunk->map[0])); + if (!chunk->map) { + kfree(chunk); + return NULL; } -} -/** - * pcpu_alloc_pages - allocates pages for @chunk - * @chunk: target chunk - * @pages: array to put the allocated pages into, indexed by pcpu_page_idx() - * @populated: populated bitmap - * @page_start: page index of the first page to be allocated - * @page_end: page index of the last page to be allocated + 1 - * - * Allocate pages [@page_start,@page_end) into @pages for all units. - * The allocation is for @chunk. Percpu core doesn't care about the - * content of @pages and will pass it verbatim to pcpu_map_pages(). - */ -static int pcpu_alloc_pages(struct pcpu_chunk *chunk, - struct page **pages, unsigned long *populated, - int page_start, int page_end) -{ - const gfp_t gfp = GFP_KERNEL | __GFP_HIGHMEM | __GFP_COLD; - unsigned int cpu; - int i; + chunk->map_alloc = PCPU_DFL_MAP_ALLOC; + chunk->map[chunk->map_used++] = pcpu_unit_size; - for_each_possible_cpu(cpu) { - for (i = page_start; i < page_end; i++) { - struct page **pagep = &pages[pcpu_page_idx(cpu, i)]; - - *pagep = alloc_pages_node(cpu_to_node(cpu), gfp, 0); - if (!*pagep) { - pcpu_free_pages(chunk, pages, populated, - page_start, page_end); - return -ENOMEM; - } - } - } - return 0; -} + INIT_LIST_HEAD(&chunk->list); + chunk->free_size = pcpu_unit_size; + chunk->contig_hint = pcpu_unit_size; -/** - * pcpu_pre_unmap_flush - flush cache prior to unmapping - * @chunk: chunk the regions to be flushed belongs to - * @page_start: page index of the first page to be flushed - * @page_end: page index of the last page to be flushed + 1 - * - * Pages in [@page_start,@page_end) of @chunk are about to be - * unmapped. Flush cache. As each flushing trial can be very - * expensive, issue flush on the whole region at once rather than - * doing it for each cpu. This could be an overkill but is more - * scalable. - */ -static void pcpu_pre_unmap_flush(struct pcpu_chunk *chunk, - int page_start, int page_end) -{ - flush_cache_vunmap( - pcpu_chunk_addr(chunk, pcpu_first_unit_cpu, page_start), - pcpu_chunk_addr(chunk, pcpu_last_unit_cpu, page_end)); + return chunk; } -static void __pcpu_unmap_pages(unsigned long addr, int nr_pages) +static void pcpu_free_chunk(struct pcpu_chunk *chunk) { - unmap_kernel_range_noflush(addr, nr_pages << PAGE_SHIFT); + if (!chunk) + return; + pcpu_mem_free(chunk->map, chunk->map_alloc * sizeof(chunk->map[0])); + kfree(chunk); } -/** - * pcpu_unmap_pages - unmap pages out of a pcpu_chunk - * @chunk: chunk of interest - * @pages: pages array which can be used to pass information to free - * @populated: populated bitmap - * @page_start: page index of the first page to unmap - * @page_end: page index of the last page to unmap + 1 - * - * For each cpu, unmap pages [@page_start,@page_end) out of @chunk. - * Corresponding elements in @pages were cleared by the caller and can - * be used to carry information to pcpu_free_pages() which will be - * called after all unmaps are finished. The caller should call - * proper pre/post flush functions. +/* + * Chunk management implementation. + * + * To allow different implementations, chunk alloc/free and + * [de]population are implemented in a separate file which is pulled + * into this file and compiled together. The following functions + * should be implemented. + * + * pcpu_populate_chunk - populate the specified range of a chunk + * pcpu_depopulate_chunk - depopulate the specified range of a chunk + * pcpu_create_chunk - create a new chunk + * pcpu_destroy_chunk - destroy a chunk, always preceded by full depop + * pcpu_addr_to_page - translate address to physical address + * pcpu_verify_alloc_info - check alloc_info is acceptable during init */ -static void pcpu_unmap_pages(struct pcpu_chunk *chunk, - struct page **pages, unsigned long *populated, - int page_start, int page_end) -{ - unsigned int cpu; - int i; - - for_each_possible_cpu(cpu) { - for (i = page_start; i < page_end; i++) { - struct page *page; - - page = pcpu_chunk_page(chunk, cpu, i); - WARN_ON(!page); - pages[pcpu_page_idx(cpu, i)] = page; - } - __pcpu_unmap_pages(pcpu_chunk_addr(chunk, cpu, page_start), - page_end - page_start); - } - - for (i = page_start; i < page_end; i++) - __clear_bit(i, populated); -} +static int pcpu_populate_chunk(struct pcpu_chunk *chunk, int off, int size); +static void pcpu_depopulate_chunk(struct pcpu_chunk *chunk, int off, int size); +static struct pcpu_chunk *pcpu_create_chunk(void); +static void pcpu_destroy_chunk(struct pcpu_chunk *chunk); +static struct page *pcpu_addr_to_page(void *addr); +static int __init pcpu_verify_alloc_info(const struct pcpu_alloc_info *ai); + +#ifdef CONFIG_NEED_PER_CPU_KM +#include "percpu-km.c" +#else +#include "percpu-vm.c" +#endif /** - * pcpu_post_unmap_tlb_flush - flush TLB after unmapping - * @chunk: pcpu_chunk the regions to be flushed belong to - * @page_start: page index of the first page to be flushed - * @page_end: page index of the last page to be flushed + 1 - * - * Pages [@page_start,@page_end) of @chunk have been unmapped. Flush - * TLB for the regions. This can be skipped if the area is to be - * returned to vmalloc as vmalloc will handle TLB flushing lazily. + * pcpu_chunk_addr_search - determine chunk containing specified address + * @addr: address for which the chunk needs to be determined. * - * As with pcpu_pre_unmap_flush(), TLB flushing also is done at once - * for the whole region. - */ -static void pcpu_post_unmap_tlb_flush(struct pcpu_chunk *chunk, - int page_start, int page_end) -{ - flush_tlb_kernel_range( - pcpu_chunk_addr(chunk, pcpu_first_unit_cpu, page_start), - pcpu_chunk_addr(chunk, pcpu_last_unit_cpu, page_end)); -} - -static int __pcpu_map_pages(unsigned long addr, struct page **pages, - int nr_pages) -{ - return map_kernel_range_noflush(addr, nr_pages << PAGE_SHIFT, - PAGE_KERNEL, pages); -} - -/** - * pcpu_map_pages - map pages into a pcpu_chunk - * @chunk: chunk of interest - * @pages: pages array containing pages to be mapped - * @populated: populated bitmap - * @page_start: page index of the first page to map - * @page_end: page index of the last page to map + 1 - * - * For each cpu, map pages [@page_start,@page_end) into @chunk. The - * caller is responsible for calling pcpu_post_map_flush() after all - * mappings are complete. - * - * This function is responsible for setting corresponding bits in - * @chunk->populated bitmap and whatever is necessary for reverse - * lookup (addr -> chunk). + * RETURNS: + * The address of the found chunk. */ -static int pcpu_map_pages(struct pcpu_chunk *chunk, - struct page **pages, unsigned long *populated, - int page_start, int page_end) +static struct pcpu_chunk *pcpu_chunk_addr_search(void *addr) { - unsigned int cpu, tcpu; - int i, err; - - for_each_possible_cpu(cpu) { - err = __pcpu_map_pages(pcpu_chunk_addr(chunk, cpu, page_start), - &pages[pcpu_page_idx(cpu, page_start)], - page_end - page_start); - if (err < 0) - goto err; - } - - /* mapping successful, link chunk and mark populated */ - for (i = page_start; i < page_end; i++) { - for_each_possible_cpu(cpu) - pcpu_set_page_chunk(pages[pcpu_page_idx(cpu, i)], - chunk); - __set_bit(i, populated); - } - - return 0; - -err: - for_each_possible_cpu(tcpu) { - if (tcpu == cpu) - break; - __pcpu_unmap_pages(pcpu_chunk_addr(chunk, tcpu, page_start), - page_end - page_start); + /* 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; } - return err; -} - -/** - * pcpu_post_map_flush - flush cache after mapping - * @chunk: pcpu_chunk the regions to be flushed belong to - * @page_start: page index of the first page to be flushed - * @page_end: page index of the last page to be flushed + 1 - * - * Pages [@page_start,@page_end) of @chunk have been mapped. Flush - * cache. - * - * As with pcpu_pre_unmap_flush(), TLB flushing also is done at once - * for the whole region. - */ -static void pcpu_post_map_flush(struct pcpu_chunk *chunk, - int page_start, int page_end) -{ - flush_cache_vmap( - pcpu_chunk_addr(chunk, pcpu_first_unit_cpu, page_start), - pcpu_chunk_addr(chunk, pcpu_last_unit_cpu, page_end)); -} - -/** - * pcpu_depopulate_chunk - depopulate and unmap an area of a pcpu_chunk - * @chunk: chunk to depopulate - * @off: offset to the area to depopulate - * @size: size of the area to depopulate in bytes - * @flush: whether to flush cache and tlb or not - * - * For each cpu, depopulate and unmap pages [@page_start,@page_end) - * from @chunk. If @flush is true, vcache is flushed before unmapping - * and tlb after. - * - * CONTEXT: - * pcpu_alloc_mutex. - */ -static void pcpu_depopulate_chunk(struct pcpu_chunk *chunk, int off, int size) -{ - int page_start = PFN_DOWN(off); - int page_end = PFN_UP(off + size); - struct page **pages; - unsigned long *populated; - int rs, re; - - /* quick path, check whether it's empty already */ - rs = page_start; - pcpu_next_unpop(chunk, &rs, &re, page_end); - if (rs == page_start && re == page_end) - return; - - /* immutable chunks can't be depopulated */ - WARN_ON(chunk->immutable); /* - * If control reaches here, there must have been at least one - * successful population attempt so the temp pages array must - * be available now. + * 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. */ - pages = pcpu_get_pages_and_bitmap(chunk, &populated, false); - BUG_ON(!pages); - - /* unmap and free */ - pcpu_pre_unmap_flush(chunk, page_start, page_end); - - pcpu_for_each_pop_region(chunk, rs, re, page_start, page_end) - pcpu_unmap_pages(chunk, pages, populated, rs, re); - - /* no need to flush tlb, vmalloc will handle it lazily */ - - pcpu_for_each_pop_region(chunk, rs, re, page_start, page_end) - pcpu_free_pages(chunk, pages, populated, rs, re); - - /* commit new bitmap */ - bitmap_copy(chunk->populated, populated, pcpu_unit_pages); -} - -/** - * pcpu_populate_chunk - populate and map an area of a pcpu_chunk - * @chunk: chunk of interest - * @off: offset to the area to populate - * @size: size of the area to populate in bytes - * - * For each cpu, populate and map pages [@page_start,@page_end) into - * @chunk. The area is cleared on return. - * - * CONTEXT: - * pcpu_alloc_mutex, does GFP_KERNEL allocation. - */ -static int pcpu_populate_chunk(struct pcpu_chunk *chunk, int off, int size) -{ - int page_start = PFN_DOWN(off); - int page_end = PFN_UP(off + size); - int free_end = page_start, unmap_end = page_start; - struct page **pages; - unsigned long *populated; - unsigned int cpu; - int rs, re, rc; - - /* quick path, check whether all pages are already there */ - rs = page_start; - pcpu_next_pop(chunk, &rs, &re, page_end); - if (rs == page_start && re == page_end) - goto clear; - - /* need to allocate and map pages, this chunk can't be immutable */ - WARN_ON(chunk->immutable); - - pages = pcpu_get_pages_and_bitmap(chunk, &populated, true); - if (!pages) - return -ENOMEM; - - /* alloc and map */ - pcpu_for_each_unpop_region(chunk, rs, re, page_start, page_end) { - rc = pcpu_alloc_pages(chunk, pages, populated, rs, re); - if (rc) - goto err_free; - free_end = re; - } - - pcpu_for_each_unpop_region(chunk, rs, re, page_start, page_end) { - rc = pcpu_map_pages(chunk, pages, populated, rs, re); - if (rc) - goto err_unmap; - unmap_end = re; - } - pcpu_post_map_flush(chunk, page_start, page_end); - - /* commit new bitmap */ - bitmap_copy(chunk->populated, populated, pcpu_unit_pages); -clear: - for_each_possible_cpu(cpu) - memset((void *)pcpu_chunk_addr(chunk, cpu, 0) + off, 0, size); - return 0; - -err_unmap: - pcpu_pre_unmap_flush(chunk, page_start, unmap_end); - pcpu_for_each_unpop_region(chunk, rs, re, page_start, unmap_end) - pcpu_unmap_pages(chunk, pages, populated, rs, re); - pcpu_post_unmap_tlb_flush(chunk, page_start, unmap_end); -err_free: - pcpu_for_each_unpop_region(chunk, rs, re, page_start, free_end) - pcpu_free_pages(chunk, pages, populated, rs, re); - return rc; -} - -static void free_pcpu_chunk(struct pcpu_chunk *chunk) -{ - if (!chunk) - return; - if (chunk->vms) - pcpu_free_vm_areas(chunk->vms, pcpu_nr_groups); - pcpu_mem_free(chunk->map, chunk->map_alloc * sizeof(chunk->map[0])); - kfree(chunk); -} - -static struct pcpu_chunk *alloc_pcpu_chunk(void) -{ - struct pcpu_chunk *chunk; - - chunk = kzalloc(pcpu_chunk_struct_size, GFP_KERNEL); - if (!chunk) - return NULL; - - chunk->map = pcpu_mem_alloc(PCPU_DFL_MAP_ALLOC * sizeof(chunk->map[0])); - chunk->map_alloc = PCPU_DFL_MAP_ALLOC; - chunk->map[chunk->map_used++] = pcpu_unit_size; - - chunk->vms = pcpu_get_vm_areas(pcpu_group_offsets, pcpu_group_sizes, - pcpu_nr_groups, pcpu_atom_size, - GFP_KERNEL); - if (!chunk->vms) { - free_pcpu_chunk(chunk); - return NULL; - } - - INIT_LIST_HEAD(&chunk->list); - chunk->free_size = pcpu_unit_size; - chunk->contig_hint = pcpu_unit_size; - chunk->base_addr = chunk->vms[0]->addr - pcpu_group_offsets[0]; - - return chunk; + addr += pcpu_unit_offsets[raw_smp_processor_id()]; + return pcpu_get_page_chunk(pcpu_addr_to_page(addr)); } /** @@ -1142,7 +773,7 @@ restart: /* hmmm... no space left, create a new chunk */ spin_unlock_irqrestore(&pcpu_lock, flags); - chunk = alloc_pcpu_chunk(); + chunk = pcpu_create_chunk(); if (!chunk) { err = "failed to allocate new chunk"; goto fail_unlock_mutex; @@ -1254,7 +885,7 @@ static void pcpu_reclaim(struct work_struct *work) list_for_each_entry_safe(chunk, next, &todo, list) { pcpu_depopulate_chunk(chunk, 0, pcpu_unit_size); - free_pcpu_chunk(chunk); + pcpu_destroy_chunk(chunk); } mutex_unlock(&pcpu_alloc_mutex); @@ -1343,25 +974,39 @@ bool is_kernel_percpu_address(unsigned long addr) */ phys_addr_t per_cpu_ptr_to_phys(void *addr) { - if ((unsigned long)addr < VMALLOC_START || - (unsigned long)addr >= VMALLOC_END) - return __pa(addr); - else - return page_to_phys(vmalloc_to_page(addr)); -} - -static inline size_t pcpu_calc_fc_sizes(size_t static_size, - size_t reserved_size, - ssize_t *dyn_sizep) -{ - size_t size_sum; + void __percpu *base = __addr_to_pcpu_ptr(pcpu_base_addr); + bool in_first_chunk = false; + unsigned long first_start, first_end; + unsigned int cpu; - size_sum = PFN_ALIGN(static_size + reserved_size + - (*dyn_sizep >= 0 ? *dyn_sizep : 0)); - if (*dyn_sizep != 0) - *dyn_sizep = size_sum - static_size - reserved_size; + /* + * The following test on first_start/end isn't strictly + * necessary but will speed up lookups of addresses which + * aren't in the first chunk. + */ + first_start = pcpu_chunk_addr(pcpu_first_chunk, pcpu_first_unit_cpu, 0); + first_end = pcpu_chunk_addr(pcpu_first_chunk, pcpu_last_unit_cpu, + pcpu_unit_pages); + if ((unsigned long)addr >= first_start && + (unsigned long)addr < first_end) { + for_each_possible_cpu(cpu) { + void *start = per_cpu_ptr(base, cpu); + + if (addr >= start && addr < start + pcpu_unit_size) { + in_first_chunk = true; + break; + } + } + } - return size_sum; + if (in_first_chunk) { + if ((unsigned long)addr < VMALLOC_START || + (unsigned long)addr >= VMALLOC_END) + return __pa(addr); + else + return page_to_phys(vmalloc_to_page(addr)); + } else + return page_to_phys(pcpu_addr_to_page(addr)); } /** @@ -1422,7 +1067,7 @@ void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai) /** * pcpu_build_alloc_info - build alloc_info considering distances between CPUs * @reserved_size: the size of reserved percpu area in bytes - * @dyn_size: free size for dynamic allocation in bytes, -1 for auto + * @dyn_size: minimum free size for dynamic allocation in bytes * @atom_size: allocation atom size * @cpu_distance_fn: callback to determine distance between cpus, optional * @@ -1440,15 +1085,15 @@ void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai) * On success, pointer to the new allocation_info is returned. On * failure, ERR_PTR value is returned. */ -struct pcpu_alloc_info * __init pcpu_build_alloc_info( - size_t reserved_size, ssize_t dyn_size, +static struct pcpu_alloc_info * __init pcpu_build_alloc_info( + size_t reserved_size, size_t dyn_size, size_t atom_size, pcpu_fc_cpu_distance_fn_t cpu_distance_fn) { static int group_map[NR_CPUS] __initdata; static int group_cnt[NR_CPUS] __initdata; const size_t static_size = __per_cpu_end - __per_cpu_start; - int group_cnt_max = 0, nr_groups = 1, nr_units = 0; + int nr_groups = 1, nr_units = 0; size_t size_sum, min_unit_size, alloc_size; int upa, max_upa, uninitialized_var(best_upa); /* units_per_alloc */ int last_allocs, group, unit; @@ -1458,7 +1103,12 @@ struct pcpu_alloc_info * __init pcpu_build_alloc_info( /* this function may be called multiple times */ memset(group_map, 0, sizeof(group_map)); - memset(group_cnt, 0, sizeof(group_map)); + memset(group_cnt, 0, sizeof(group_cnt)); + + /* calculate size_sum and ensure dyn_size is enough for early alloc */ + size_sum = PFN_ALIGN(static_size + reserved_size + + max_t(size_t, dyn_size, PERCPU_DYNAMIC_EARLY_SIZE)); + dyn_size = size_sum - static_size - reserved_size; /* * Determine min_unit_size, alloc_size and max_upa such that @@ -1466,7 +1116,6 @@ struct pcpu_alloc_info * __init pcpu_build_alloc_info( * which can accomodate 4k aligned segments which are equal to * or larger than min_unit_size. */ - size_sum = pcpu_calc_fc_sizes(static_size, reserved_size, &dyn_size); min_unit_size = max_t(size_t, size_sum, PCPU_MIN_UNIT_SIZE); alloc_size = roundup(min_unit_size, atom_size); @@ -1492,7 +1141,6 @@ struct pcpu_alloc_info * __init pcpu_build_alloc_info( } group_map[cpu] = group; group_cnt[group]++; - group_cnt_max = max(group_cnt_max, group_cnt[group]); } /* @@ -1688,7 +1336,8 @@ int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai, void *base_addr) { static char cpus_buf[4096] __initdata; - static int smap[2], dmap[2]; + static int smap[PERCPU_DYNAMIC_EARLY_SLOTS] __initdata; + static int dmap[PERCPU_DYNAMIC_EARLY_SLOTS] __initdata; size_t dyn_size = ai->dyn_size; size_t size_sum = ai->static_size + ai->reserved_size + dyn_size; struct pcpu_chunk *schunk, *dchunk = NULL; @@ -1711,14 +1360,14 @@ int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai, } while (0) /* sanity checks */ - BUILD_BUG_ON(ARRAY_SIZE(smap) >= PCPU_DFL_MAP_ALLOC || - ARRAY_SIZE(dmap) >= PCPU_DFL_MAP_ALLOC); PCPU_SETUP_BUG_ON(ai->nr_groups <= 0); PCPU_SETUP_BUG_ON(!ai->static_size); PCPU_SETUP_BUG_ON(!base_addr); PCPU_SETUP_BUG_ON(ai->unit_size < size_sum); PCPU_SETUP_BUG_ON(ai->unit_size & ~PAGE_MASK); PCPU_SETUP_BUG_ON(ai->unit_size < PCPU_MIN_UNIT_SIZE); + PCPU_SETUP_BUG_ON(ai->dyn_size < PERCPU_DYNAMIC_EARLY_SIZE); + PCPU_SETUP_BUG_ON(pcpu_verify_alloc_info(ai) < 0); /* process group information and build config tables accordingly */ group_offsets = alloc_bootmem(ai->nr_groups * sizeof(group_offsets[0])); @@ -1869,7 +1518,7 @@ early_param("percpu_alloc", percpu_alloc_setup); /** * pcpu_embed_first_chunk - embed the first percpu chunk into bootmem * @reserved_size: the size of reserved percpu area in bytes - * @dyn_size: free size for dynamic allocation in bytes, -1 for auto + * @dyn_size: minimum free size for dynamic allocation in bytes * @atom_size: allocation atom size * @cpu_distance_fn: callback to determine distance between cpus, optional * @alloc_fn: function to allocate percpu page @@ -1890,10 +1539,7 @@ early_param("percpu_alloc", percpu_alloc_setup); * vmalloc space is not orders of magnitude larger than distances * between node memory addresses (ie. 32bit NUMA machines). * - * When @dyn_size is positive, dynamic area might be larger than - * specified to fill page alignment. When @dyn_size is auto, - * @dyn_size is just big enough to fill page alignment after static - * and reserved areas. + * @dyn_size specifies the minimum dynamic area size. * * If the needed size is smaller than the minimum or specified unit * size, the leftover is returned using @free_fn. @@ -1901,7 +1547,7 @@ early_param("percpu_alloc", percpu_alloc_setup); * RETURNS: * 0 on success, -errno on failure. */ -int __init pcpu_embed_first_chunk(size_t reserved_size, ssize_t dyn_size, +int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size, size_t atom_size, pcpu_fc_cpu_distance_fn_t cpu_distance_fn, pcpu_fc_alloc_fn_t alloc_fn, @@ -2032,7 +1678,7 @@ int __init pcpu_page_first_chunk(size_t reserved_size, snprintf(psize_str, sizeof(psize_str), "%luK", PAGE_SIZE >> 10); - ai = pcpu_build_alloc_info(reserved_size, -1, PAGE_SIZE, NULL); + ai = pcpu_build_alloc_info(reserved_size, 0, PAGE_SIZE, NULL); if (IS_ERR(ai)) return PTR_ERR(ai); BUG_ON(ai->nr_groups != 1); @@ -2158,3 +1804,33 @@ void __init setup_per_cpu_areas(void) __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu]; } #endif /* CONFIG_HAVE_SETUP_PER_CPU_AREA */ + +/* + * First and reserved chunks are initialized with temporary allocation + * map in initdata so that they can be used before slab is online. + * This function is called after slab is brought up and replaces those + * with properly allocated maps. + */ +void __init percpu_init_late(void) +{ + struct pcpu_chunk *target_chunks[] = + { pcpu_first_chunk, pcpu_reserved_chunk, NULL }; + struct pcpu_chunk *chunk; + unsigned long flags; + int i; + + for (i = 0; (chunk = target_chunks[i]); i++) { + int *map; + const size_t size = PERCPU_DYNAMIC_EARLY_SLOTS * sizeof(map[0]); + + BUILD_BUG_ON(size > PAGE_SIZE); + + map = pcpu_mem_alloc(size); + BUG_ON(!map); + + spin_lock_irqsave(&pcpu_lock, flags); + memcpy(map, chunk->map, size); + chunk->map = map; + spin_unlock_irqrestore(&pcpu_lock, flags); + } +} |