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-rw-r--r--mm/percpu.c111
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)