mm: compaction: defer compaction using an exponential backoff when compaction fails
[safe/jmp/linux-2.6] / mm / percpu.c
index 083e7c9..39f7dfd 100644 (file)
@@ -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
  *  -------------------          -------------------        ------------
 /* default addr <-> pcpu_ptr mapping, override in asm/percpu.h if necessary */
 #ifndef __addr_to_pcpu_ptr
 #define __addr_to_pcpu_ptr(addr)                                       \
-       (void *)((unsigned long)(addr) - (unsigned long)pcpu_base_addr  \
-                + (unsigned long)__per_cpu_start)
+       (void __percpu *)((unsigned long)(addr) -                       \
+                         (unsigned long)pcpu_base_addr +               \
+                         (unsigned long)__per_cpu_start)
 #endif
 #ifndef __pcpu_ptr_to_addr
 #define __pcpu_ptr_to_addr(ptr)                                                \
-       (void *)((unsigned long)(ptr) + (unsigned long)pcpu_base_addr   \
-                - (unsigned long)__per_cpu_start)
+       (void __force *)((unsigned long)(ptr) +                         \
+                        (unsigned long)pcpu_base_addr -                \
+                        (unsigned long)__per_cpu_start)
 #endif
 
 struct pcpu_chunk {
@@ -97,7 +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 */
 };
@@ -175,6 +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 */
@@ -196,27 +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)
 {
@@ -229,13 +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 __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);
+}
+
+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);
@@ -324,36 +333,6 @@ 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
  *
@@ -621,436 +600,92 @@ 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 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;
-
-       for_each_possible_cpu(cpu) {
-               for (i = page_start; i < page_end; i++) {
-                       struct page *page = pages[pcpu_page_idx(cpu, i)];
-
-                       if (page)
-                               __free_page(page);
-               }
-       }
-}
-
-/**
- * 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;
-
-       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;
-}
-
-/**
- * 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));
-}
-
-static void __pcpu_unmap_pages(unsigned long addr, int nr_pages)
+static struct pcpu_chunk *pcpu_alloc_chunk(void)
 {
-       unmap_kernel_range_noflush(addr, nr_pages << PAGE_SHIFT);
-}
-
-/**
- * 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.
- */
-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;
+       struct pcpu_chunk *chunk;
 
-       for_each_possible_cpu(cpu) {
-               for (i = page_start; i < page_end; i++) {
-                       struct page *page;
+       chunk = kzalloc(pcpu_chunk_struct_size, GFP_KERNEL);
+       if (!chunk)
+               return NULL;
 
-                       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);
+       chunk->map = pcpu_mem_alloc(PCPU_DFL_MAP_ALLOC * sizeof(chunk->map[0]));
+       if (!chunk->map) {
+               kfree(chunk);
+               return NULL;
        }
 
-       for (i = page_start; i < page_end; i++)
-               __clear_bit(i, populated);
-}
+       chunk->map_alloc = PCPU_DFL_MAP_ALLOC;
+       chunk->map[chunk->map_used++] = pcpu_unit_size;
 
-/**
- * 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.
- *
- * 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));
-}
+       INIT_LIST_HEAD(&chunk->list);
+       chunk->free_size = pcpu_unit_size;
+       chunk->contig_hint = pcpu_unit_size;
 
-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);
+       return chunk;
 }
 
-/**
- * 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).
- */
-static int pcpu_map_pages(struct pcpu_chunk *chunk,
-                         struct page **pages, unsigned long *populated,
-                         int page_start, int page_end)
+static void pcpu_free_chunk(struct pcpu_chunk *chunk)
 {
-       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);
-       }
-       return err;
+       if (!chunk)
+               return;
+       pcpu_mem_free(chunk->map, chunk->map_alloc * sizeof(chunk->map[0]));
+       kfree(chunk);
 }
 
-/**
- * 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.
+/*
+ * 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_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));
-}
+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_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.
+ * pcpu_chunk_addr_search - determine chunk containing specified address
+ * @addr: address for which the chunk needs to be determined.
  *
- * CONTEXT:
- * pcpu_alloc_mutex.
+ * RETURNS:
+ * The address of the found chunk.
  */
-static void pcpu_depopulate_chunk(struct pcpu_chunk *chunk, int off, int size)
+static struct pcpu_chunk *pcpu_chunk_addr_search(void *addr)
 {
-       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 */
-       pcpu_for_each_unpop_region(chunk, rs, re, page_start, page_end) {
-               if (rs == page_start && re == page_end)
-                       return;
-               break;
+       /* 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;
        }
 
-       /* 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 */
-       pcpu_for_each_pop_region(chunk, rs, re, page_start, page_end) {
-               if (rs == page_start && re == page_end)
-                       goto clear;
-               break;
-       }
-
-       /* 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));
 }
 
 /**
@@ -1067,7 +702,7 @@ static struct pcpu_chunk *alloc_pcpu_chunk(void)
  * RETURNS:
  * Percpu pointer to the allocated area on success, NULL on failure.
  */
-static void *pcpu_alloc(size_t size, size_t align, bool reserved)
+static void __percpu *pcpu_alloc(size_t size, size_t align, bool reserved)
 {
        static int warn_limit = 10;
        struct pcpu_chunk *chunk;
@@ -1142,7 +777,7 @@ 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;
@@ -1196,7 +831,7 @@ fail_unlock_mutex:
  * RETURNS:
  * Percpu pointer to the allocated area on success, NULL on failure.
  */
-void *__alloc_percpu(size_t size, size_t align)
+void __percpu *__alloc_percpu(size_t size, size_t align)
 {
        return pcpu_alloc(size, align, false);
 }
@@ -1217,7 +852,7 @@ EXPORT_SYMBOL_GPL(__alloc_percpu);
  * RETURNS:
  * Percpu pointer to the allocated area on success, NULL on failure.
  */
-void *__alloc_reserved_percpu(size_t size, size_t align)
+void __percpu *__alloc_reserved_percpu(size_t size, size_t align)
 {
        return pcpu_alloc(size, align, true);
 }
@@ -1254,7 +889,7 @@ 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);
@@ -1269,7 +904,7 @@ static void pcpu_reclaim(struct work_struct *work)
  * CONTEXT:
  * Can be called from atomic context.
  */
-void free_percpu(void *ptr)
+void free_percpu(void __percpu *ptr)
 {
        void *addr;
        struct pcpu_chunk *chunk;
@@ -1304,6 +939,32 @@ void free_percpu(void *ptr)
 EXPORT_SYMBOL_GPL(free_percpu);
 
 /**
+ * is_kernel_percpu_address - test whether address is from static percpu area
+ * @addr: address to test
+ *
+ * Test whether @addr belongs to in-kernel static percpu area.  Module
+ * static percpu areas are not considered.  For those, use
+ * is_module_percpu_address().
+ *
+ * RETURNS:
+ * %true if @addr is from in-kernel static percpu area, %false otherwise.
+ */
+bool is_kernel_percpu_address(unsigned long addr)
+{
+       const size_t static_size = __per_cpu_end - __per_cpu_start;
+       void __percpu *base = __addr_to_pcpu_ptr(pcpu_base_addr);
+       unsigned int cpu;
+
+       for_each_possible_cpu(cpu) {
+               void *start = per_cpu_ptr(base, cpu);
+
+               if ((void *)addr >= start && (void *)addr < start + static_size)
+                       return true;
+        }
+       return false;
+}
+
+/**
  * per_cpu_ptr_to_phys - convert translated percpu address to physical address
  * @addr: the address to be converted to physical address
  *
@@ -1317,11 +978,14 @@ EXPORT_SYMBOL_GPL(free_percpu);
  */
 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));
+       if (pcpu_addr_in_first_chunk(addr)) {
+               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));
 }
 
 static inline size_t pcpu_calc_fc_sizes(size_t static_size,
@@ -1693,6 +1357,7 @@ int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
        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(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]));