percpu: move vmalloc based chunk management into percpu-vm.c
Separate out and move chunk management (creation/desctruction and [de]population) code into percpu-vm.c which is included by percpu.c and compiled together. The interface for chunk management is defined as follows. * 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 Other than wrapping vmalloc_to_page() inside pcpu_addr_to_page() and dummy pcpu_verify_alloc_info() implementation, this patch only moves code around. This separation is to allow alternate chunk management implementation. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: David Howells <dhowells@redhat.com> Cc: Graff Yang <graff.yang@gmail.com> Cc: Sonic Zhang <sonic.adi@gmail.com>
This commit is contained in:
Tejun Heo
Родитель
88999a898b
Коммит
9f64553256
|
|
@ -0,0 +1,451 @@
|
|||
/*
|
||||
* mm/percpu-vm.c - vmalloc area based chunk allocation
|
||||
*
|
||||
* Copyright (C) 2010 SUSE Linux Products GmbH
|
||||
* Copyright (C) 2010 Tejun Heo <tj@kernel.org>
|
||||
*
|
||||
* This file is released under the GPLv2.
|
||||
*
|
||||
* Chunks are mapped into vmalloc areas and populated page by page.
|
||||
* This is the default chunk allocator.
|
||||
*/
|
||||
|
||||
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));
|
||||
}
|
||||
|
||||
/**
|
||||
* 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)
|
||||
{
|
||||
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;
|
||||
|
||||
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);
|
||||
}
|
||||
|
||||
/**
|
||||
* 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));
|
||||
}
|
||||
|
||||
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).
|
||||
*/
|
||||
static int pcpu_map_pages(struct pcpu_chunk *chunk,
|
||||
struct page **pages, unsigned long *populated,
|
||||
int page_start, int page_end)
|
||||
{
|
||||
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;
|
||||
}
|
||||
|
||||
/**
|
||||
* 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_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;
|
||||
}
|
||||
|
||||
/**
|
||||
* 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.
|
||||
*/
|
||||
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);
|
||||
}
|
||||
|
||||
static struct pcpu_chunk *pcpu_create_chunk(void)
|
||||
{
|
||||
struct pcpu_chunk *chunk;
|
||||
struct vm_struct **vms;
|
||||
|
||||
chunk = pcpu_alloc_chunk();
|
||||
if (!chunk)
|
||||
return NULL;
|
||||
|
||||
vms = pcpu_get_vm_areas(pcpu_group_offsets, pcpu_group_sizes,
|
||||
pcpu_nr_groups, pcpu_atom_size, GFP_KERNEL);
|
||||
if (!vms) {
|
||||
pcpu_free_chunk(chunk);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
chunk->data = vms;
|
||||
chunk->base_addr = vms[0]->addr - pcpu_group_offsets[0];
|
||||
return chunk;
|
||||
}
|
||||
|
||||
static void pcpu_destroy_chunk(struct pcpu_chunk *chunk)
|
||||
{
|
||||
if (chunk && chunk->data)
|
||||
pcpu_free_vm_areas(chunk->data, pcpu_nr_groups);
|
||||
pcpu_free_chunk(chunk);
|
||||
}
|
||||
|
||||
static struct page *pcpu_addr_to_page(void *addr)
|
||||
{
|
||||
return vmalloc_to_page(addr);
|
||||
}
|
||||
|
||||
static int __init pcpu_verify_alloc_info(const struct pcpu_alloc_info *ai)
|
||||
{
|
||||
/* no extra restriction */
|
||||
return 0;
|
||||
}
|
||||
448
mm/percpu.c
448
mm/percpu.c
|
|
@ -236,15 +236,6 @@ static unsigned long __maybe_unused pcpu_chunk_addr(struct pcpu_chunk *chunk,
|
|||
(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));
|
||||
}
|
||||
|
||||
static void __maybe_unused pcpu_next_unpop(struct pcpu_chunk *chunk,
|
||||
int *rs, int *re, int end)
|
||||
{
|
||||
|
|
@ -641,425 +632,29 @@ static void pcpu_free_chunk(struct pcpu_chunk *chunk)
|
|||
kfree(chunk);
|
||||
}
|
||||
|
||||
/**
|
||||
* 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
|
||||
/*
|
||||
* Chunk management implementation.
|
||||
*
|
||||
* 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.
|
||||
* 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.
|
||||
*
|
||||
* 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.
|
||||
* 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 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);
|
||||
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);
|
||||
|
||||
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)
|
||||
{
|
||||
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;
|
||||
|
||||
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);
|
||||
}
|
||||
|
||||
/**
|
||||
* 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));
|
||||
}
|
||||
|
||||
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).
|
||||
*/
|
||||
static int pcpu_map_pages(struct pcpu_chunk *chunk,
|
||||
struct page **pages, unsigned long *populated,
|
||||
int page_start, int page_end)
|
||||
{
|
||||
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;
|
||||
}
|
||||
|
||||
/**
|
||||
* 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.
|
||||
*/
|
||||
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 pcpu_destroy_chunk(struct pcpu_chunk *chunk)
|
||||
{
|
||||
if (chunk && chunk->data)
|
||||
pcpu_free_vm_areas(chunk->data, pcpu_nr_groups);
|
||||
pcpu_free_chunk(chunk);
|
||||
}
|
||||
|
||||
static struct pcpu_chunk *pcpu_create_chunk(void)
|
||||
{
|
||||
struct pcpu_chunk *chunk;
|
||||
struct vm_struct **vms;
|
||||
|
||||
chunk = pcpu_alloc_chunk();
|
||||
if (!chunk)
|
||||
return NULL;
|
||||
|
||||
vms = pcpu_get_vm_areas(pcpu_group_offsets, pcpu_group_sizes,
|
||||
pcpu_nr_groups, pcpu_atom_size, GFP_KERNEL);
|
||||
if (!vms) {
|
||||
pcpu_free_chunk(chunk);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
chunk->data = vms;
|
||||
chunk->base_addr = vms[0]->addr - pcpu_group_offsets[0];
|
||||
return chunk;
|
||||
}
|
||||
#include "percpu-vm.c"
|
||||
|
||||
/**
|
||||
* pcpu_chunk_addr_search - determine chunk containing specified address
|
||||
|
|
@ -1086,7 +681,7 @@ static struct pcpu_chunk *pcpu_chunk_addr_search(void *addr)
|
|||
* 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));
|
||||
return pcpu_get_page_chunk(pcpu_addr_to_page(addr));
|
||||
}
|
||||
|
||||
/**
|
||||
|
|
@ -1386,7 +981,7 @@ phys_addr_t per_cpu_ptr_to_phys(void *addr)
|
|||
else
|
||||
return page_to_phys(vmalloc_to_page(addr));
|
||||
} else
|
||||
return page_to_phys(vmalloc_to_page(addr));
|
||||
return page_to_phys(pcpu_addr_to_page(addr));
|
||||
}
|
||||
|
||||
static inline size_t pcpu_calc_fc_sizes(size_t static_size,
|
||||
|
|
@ -1758,6 +1353,7 @@ 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]));
|
||||
|
|
|
|||
Загрузка…
Ссылка в новой задаче