BACKPORT: mm/zsmalloc: adjust order of functions

(cherry-pick from commit 66cdef663cd7a97aff6bbbf41a81a0205dc81ba2)

Currently functions in zsmalloc.c does not arranged in a readable and
reasonable sequence.  With the more and more functions added, we may
meet below inconvenience.  For example:

Current functions:

    void zs_init()
    {
    }

    static void get_maxobj_per_zspage()
    {
    }

Then I want to add a func_1() which is called from zs_init(), and this
new added function func_1() will used get_maxobj_per_zspage() which is
defined below zs_init().

    void func_1()
    {
        get_maxobj_per_zspage()
    }

    void zs_init()
    {
        func_1()
    }

    static void get_maxobj_per_zspage()
    {
    }

This will cause compiling issue. So we must add a declaration:

    static void get_maxobj_per_zspage();

before func_1() if we do not put get_maxobj_per_zspage() before
func_1().

In addition, puting module_[init|exit] functions at the bottom of the
file conforms to our habit.

So, this patch ajusts function sequence as:

    /* helper functions */
    ...
    obj_location_to_handle()
    ...

    /* Some exported functions */
    ...

    zs_map_object()
    zs_unmap_object()

    zs_malloc()
    zs_free()

    zs_init()
    zs_exit()

Bug: 25951511

Change-Id: I68377a213ade041b34e99a4280ebd57a933dfa83
Signed-off-by: Ganesh Mahendran <opensource.ganesh@gmail.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Ganesh Mahendran 2014-12-18 16:17:40 -08:00 committed by Srinivasarao P
parent caeae3dbac
commit bc7a7b9717

View file

@ -885,19 +885,6 @@ static struct notifier_block zs_cpu_nb = {
.notifier_call = zs_cpu_notifier
};
static void zs_unregister_cpu_notifier(void)
{
int cpu;
cpu_notifier_register_begin();
for_each_online_cpu(cpu)
zs_cpu_notifier(NULL, CPU_DEAD, (void *)(long)cpu);
__unregister_cpu_notifier(&zs_cpu_nb);
cpu_notifier_register_done();
}
static int zs_register_cpu_notifier(void)
{
int cpu, uninitialized_var(ret);
@ -915,6 +902,19 @@ static int zs_register_cpu_notifier(void)
return notifier_to_errno(ret);
}
static void zs_unregister_cpu_notifier(void)
{
int cpu;
cpu_notifier_register_begin();
for_each_online_cpu(cpu)
zs_cpu_notifier(NULL, CPU_DEAD, (void *)(long)cpu);
__unregister_cpu_notifier(&zs_cpu_nb);
cpu_notifier_register_done();
}
static void init_zs_size_classes(void)
{
int nr;
@ -926,31 +926,6 @@ static void init_zs_size_classes(void)
zs_size_classes = nr;
}
static void __exit zs_exit(void)
{
#ifdef CONFIG_ZPOOL
zpool_unregister_driver(&zs_zpool_driver);
#endif
zs_unregister_cpu_notifier();
}
static int __init zs_init(void)
{
int ret = zs_register_cpu_notifier();
if (ret) {
zs_unregister_cpu_notifier();
return ret;
}
init_zs_size_classes();
#ifdef CONFIG_ZPOOL
zpool_register_driver(&zs_zpool_driver);
#endif
return 0;
}
static unsigned int get_maxobj_per_zspage(int size, int pages_per_zspage)
{
return pages_per_zspage * PAGE_SIZE / size;
@ -968,6 +943,202 @@ static bool can_merge(struct size_class *prev, int size, int pages_per_zspage)
return true;
}
unsigned long zs_get_total_pages(struct zs_pool *pool)
{
return atomic_long_read(&pool->pages_allocated);
}
EXPORT_SYMBOL_GPL(zs_get_total_pages);
/**
* zs_map_object - get address of allocated object from handle.
* @pool: pool from which the object was allocated
* @handle: handle returned from zs_malloc
*
* Before using an object allocated from zs_malloc, it must be mapped using
* this function. When done with the object, it must be unmapped using
* zs_unmap_object.
*
* Only one object can be mapped per cpu at a time. There is no protection
* against nested mappings.
*
* This function returns with preemption and page faults disabled.
*/
void *zs_map_object(struct zs_pool *pool, unsigned long handle,
enum zs_mapmode mm)
{
struct page *page;
unsigned long obj_idx, off;
unsigned int class_idx;
enum fullness_group fg;
struct size_class *class;
struct mapping_area *area;
struct page *pages[2];
BUG_ON(!handle);
/*
* Because we use per-cpu mapping areas shared among the
* pools/users, we can't allow mapping in interrupt context
* because it can corrupt another users mappings.
*/
BUG_ON(in_interrupt());
obj_handle_to_location(handle, &page, &obj_idx);
get_zspage_mapping(get_first_page(page), &class_idx, &fg);
class = pool->size_class[class_idx];
off = obj_idx_to_offset(page, obj_idx, class->size);
area = &get_cpu_var(zs_map_area);
area->vm_mm = mm;
if (off + class->size <= PAGE_SIZE) {
/* this object is contained entirely within a page */
area->vm_addr = kmap_atomic(page);
return area->vm_addr + off;
}
/* this object spans two pages */
pages[0] = page;
pages[1] = get_next_page(page);
BUG_ON(!pages[1]);
return __zs_map_object(area, pages, off, class->size);
}
EXPORT_SYMBOL_GPL(zs_map_object);
void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
{
struct page *page;
unsigned long obj_idx, off;
unsigned int class_idx;
enum fullness_group fg;
struct size_class *class;
struct mapping_area *area;
BUG_ON(!handle);
obj_handle_to_location(handle, &page, &obj_idx);
get_zspage_mapping(get_first_page(page), &class_idx, &fg);
class = pool->size_class[class_idx];
off = obj_idx_to_offset(page, obj_idx, class->size);
area = this_cpu_ptr(&zs_map_area);
if (off + class->size <= PAGE_SIZE)
kunmap_atomic(area->vm_addr);
else {
struct page *pages[2];
pages[0] = page;
pages[1] = get_next_page(page);
BUG_ON(!pages[1]);
__zs_unmap_object(area, pages, off, class->size);
}
put_cpu_var(zs_map_area);
}
EXPORT_SYMBOL_GPL(zs_unmap_object);
/**
* zs_malloc - Allocate block of given size from pool.
* @pool: pool to allocate from
* @size: size of block to allocate
*
* On success, handle to the allocated object is returned,
* otherwise 0.
* Allocation requests with size > ZS_MAX_ALLOC_SIZE will fail.
*/
unsigned long zs_malloc(struct zs_pool *pool, size_t size)
{
unsigned long obj;
struct link_free *link;
struct size_class *class;
void *vaddr;
struct page *first_page, *m_page;
unsigned long m_objidx, m_offset;
if (unlikely(!size || size > ZS_MAX_ALLOC_SIZE))
return 0;
class = pool->size_class[get_size_class_index(size)];
spin_lock(&class->lock);
first_page = find_get_zspage(class);
if (!first_page) {
spin_unlock(&class->lock);
first_page = alloc_zspage(class, pool->flags);
if (unlikely(!first_page))
return 0;
set_zspage_mapping(first_page, class->index, ZS_EMPTY);
atomic_long_add(class->pages_per_zspage,
&pool->pages_allocated);
spin_lock(&class->lock);
}
obj = (unsigned long)first_page->freelist;
obj_handle_to_location(obj, &m_page, &m_objidx);
m_offset = obj_idx_to_offset(m_page, m_objidx, class->size);
vaddr = kmap_atomic(m_page);
link = (struct link_free *)vaddr + m_offset / sizeof(*link);
first_page->freelist = link->next;
memset(link, POISON_INUSE, sizeof(*link));
kunmap_atomic(vaddr);
first_page->inuse++;
/* Now move the zspage to another fullness group, if required */
fix_fullness_group(pool, first_page);
spin_unlock(&class->lock);
return obj;
}
EXPORT_SYMBOL_GPL(zs_malloc);
void zs_free(struct zs_pool *pool, unsigned long obj)
{
struct link_free *link;
struct page *first_page, *f_page;
unsigned long f_objidx, f_offset;
void *vaddr;
int class_idx;
struct size_class *class;
enum fullness_group fullness;
if (unlikely(!obj))
return;
obj_handle_to_location(obj, &f_page, &f_objidx);
first_page = get_first_page(f_page);
get_zspage_mapping(first_page, &class_idx, &fullness);
class = pool->size_class[class_idx];
f_offset = obj_idx_to_offset(f_page, f_objidx, class->size);
spin_lock(&class->lock);
/* Insert this object in containing zspage's freelist */
vaddr = kmap_atomic(f_page);
link = (struct link_free *)(vaddr + f_offset);
link->next = first_page->freelist;
kunmap_atomic(vaddr);
first_page->freelist = (void *)obj;
first_page->inuse--;
fullness = fix_fullness_group(pool, first_page);
spin_unlock(&class->lock);
if (fullness == ZS_EMPTY) {
atomic_long_sub(class->pages_per_zspage,
&pool->pages_allocated);
free_zspage(first_page);
}
}
EXPORT_SYMBOL_GPL(zs_free);
/**
* zs_create_pool - Creates an allocation pool to work from.
* @flags: allocation flags used to allocate pool metadata
@ -1076,201 +1247,30 @@ void zs_destroy_pool(struct zs_pool *pool)
}
EXPORT_SYMBOL_GPL(zs_destroy_pool);
/**
* zs_malloc - Allocate block of given size from pool.
* @pool: pool to allocate from
* @size: size of block to allocate
*
* On success, handle to the allocated object is returned,
* otherwise 0.
* Allocation requests with size > ZS_MAX_ALLOC_SIZE will fail.
*/
unsigned long zs_malloc(struct zs_pool *pool, size_t size)
static int __init zs_init(void)
{
unsigned long obj;
struct link_free *link;
struct size_class *class;
void *vaddr;
int ret = zs_register_cpu_notifier();
struct page *first_page, *m_page;
unsigned long m_objidx, m_offset;
if (unlikely(!size || size > ZS_MAX_ALLOC_SIZE))
return 0;
class = pool->size_class[get_size_class_index(size)];
spin_lock(&class->lock);
first_page = find_get_zspage(class);
if (!first_page) {
spin_unlock(&class->lock);
first_page = alloc_zspage(class, pool->flags);
if (unlikely(!first_page))
return 0;
set_zspage_mapping(first_page, class->index, ZS_EMPTY);
atomic_long_add(class->pages_per_zspage,
&pool->pages_allocated);
spin_lock(&class->lock);
if (ret) {
zs_unregister_cpu_notifier();
return ret;
}
obj = (unsigned long)first_page->freelist;
obj_handle_to_location(obj, &m_page, &m_objidx);
m_offset = obj_idx_to_offset(m_page, m_objidx, class->size);
init_zs_size_classes();
vaddr = kmap_atomic(m_page);
link = (struct link_free *)vaddr + m_offset / sizeof(*link);
first_page->freelist = link->next;
memset(link, POISON_INUSE, sizeof(*link));
kunmap_atomic(vaddr);
first_page->inuse++;
/* Now move the zspage to another fullness group, if required */
fix_fullness_group(pool, first_page);
spin_unlock(&class->lock);
return obj;
#ifdef CONFIG_ZPOOL
zpool_register_driver(&zs_zpool_driver);
#endif
return 0;
}
EXPORT_SYMBOL_GPL(zs_malloc);
void zs_free(struct zs_pool *pool, unsigned long obj)
static void __exit zs_exit(void)
{
struct link_free *link;
struct page *first_page, *f_page;
unsigned long f_objidx, f_offset;
void *vaddr;
int class_idx;
struct size_class *class;
enum fullness_group fullness;
if (unlikely(!obj))
return;
obj_handle_to_location(obj, &f_page, &f_objidx);
first_page = get_first_page(f_page);
get_zspage_mapping(first_page, &class_idx, &fullness);
class = pool->size_class[class_idx];
f_offset = obj_idx_to_offset(f_page, f_objidx, class->size);
spin_lock(&class->lock);
/* Insert this object in containing zspage's freelist */
vaddr = kmap_atomic(f_page);
link = (struct link_free *)(vaddr + f_offset);
link->next = first_page->freelist;
kunmap_atomic(vaddr);
first_page->freelist = (void *)obj;
first_page->inuse--;
fullness = fix_fullness_group(pool, first_page);
spin_unlock(&class->lock);
if (fullness == ZS_EMPTY) {
atomic_long_sub(class->pages_per_zspage,
&pool->pages_allocated);
free_zspage(first_page);
}
#ifdef CONFIG_ZPOOL
zpool_unregister_driver(&zs_zpool_driver);
#endif
zs_unregister_cpu_notifier();
}
EXPORT_SYMBOL_GPL(zs_free);
/**
* zs_map_object - get address of allocated object from handle.
* @pool: pool from which the object was allocated
* @handle: handle returned from zs_malloc
*
* Before using an object allocated from zs_malloc, it must be mapped using
* this function. When done with the object, it must be unmapped using
* zs_unmap_object.
*
* Only one object can be mapped per cpu at a time. There is no protection
* against nested mappings.
*
* This function returns with preemption and page faults disabled.
*/
void *zs_map_object(struct zs_pool *pool, unsigned long handle,
enum zs_mapmode mm)
{
struct page *page;
unsigned long obj_idx, off;
unsigned int class_idx;
enum fullness_group fg;
struct size_class *class;
struct mapping_area *area;
struct page *pages[2];
BUG_ON(!handle);
/*
* Because we use per-cpu mapping areas shared among the
* pools/users, we can't allow mapping in interrupt context
* because it can corrupt another users mappings.
*/
BUG_ON(in_interrupt());
obj_handle_to_location(handle, &page, &obj_idx);
get_zspage_mapping(get_first_page(page), &class_idx, &fg);
class = pool->size_class[class_idx];
off = obj_idx_to_offset(page, obj_idx, class->size);
area = &get_cpu_var(zs_map_area);
area->vm_mm = mm;
if (off + class->size <= PAGE_SIZE) {
/* this object is contained entirely within a page */
area->vm_addr = kmap_atomic(page);
return area->vm_addr + off;
}
/* this object spans two pages */
pages[0] = page;
pages[1] = get_next_page(page);
BUG_ON(!pages[1]);
return __zs_map_object(area, pages, off, class->size);
}
EXPORT_SYMBOL_GPL(zs_map_object);
void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
{
struct page *page;
unsigned long obj_idx, off;
unsigned int class_idx;
enum fullness_group fg;
struct size_class *class;
struct mapping_area *area;
BUG_ON(!handle);
obj_handle_to_location(handle, &page, &obj_idx);
get_zspage_mapping(get_first_page(page), &class_idx, &fg);
class = pool->size_class[class_idx];
off = obj_idx_to_offset(page, obj_idx, class->size);
area = &__get_cpu_var(zs_map_area);
if (off + class->size <= PAGE_SIZE)
kunmap_atomic(area->vm_addr);
else {
struct page *pages[2];
pages[0] = page;
pages[1] = get_next_page(page);
BUG_ON(!pages[1]);
__zs_unmap_object(area, pages, off, class->size);
}
put_cpu_var(zs_map_area);
}
EXPORT_SYMBOL_GPL(zs_unmap_object);
unsigned long zs_get_total_pages(struct zs_pool *pool)
{
return atomic_long_read(&pool->pages_allocated);
}
EXPORT_SYMBOL_GPL(zs_get_total_pages);
module_init(zs_init);
module_exit(zs_exit);