[RFC][PATCH 06/10] zsmalloc: move compaction functions

From: Sergey Senozhatsky
Date: Fri May 29 2015 - 11:10:04 EST


this patch simply moves compaction functions, so we can call
`static __zs_compaction()' (and friends) from zs_free().

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@xxxxxxxxx>
---
mm/zsmalloc.c | 426 +++++++++++++++++++++++++++++-----------------------------
1 file changed, 215 insertions(+), 211 deletions(-)

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index 54eefc3..c2a640a 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -321,6 +321,7 @@ static int zs_zpool_malloc(void *pool, size_t size, gfp_t gfp,
*handle = zs_malloc(pool, size);
return *handle ? 0 : -1;
}
+
static void zs_zpool_free(void *pool, unsigned long handle)
{
zs_free(pool, handle);
@@ -352,6 +353,7 @@ static void *zs_zpool_map(void *pool, unsigned long handle,

return zs_map_object(pool, handle, zs_mm);
}
+
static void zs_zpool_unmap(void *pool, unsigned long handle)
{
zs_unmap_object(pool, handle);
@@ -590,7 +592,6 @@ static inline void zs_pool_stat_destroy(struct zs_pool *pool)
}
#endif

-
/*
* For each size class, zspages are divided into different groups
* depending on how "full" they are. This was done so that we could
@@ -1117,7 +1118,6 @@ out:
/* enable page faults to match kunmap_atomic() return conditions */
pagefault_enable();
}
-
#endif /* CONFIG_PGTABLE_MAPPING */

static int zs_cpu_notifier(struct notifier_block *nb, unsigned long action,
@@ -1207,115 +1207,6 @@ static bool zspage_full(struct page *page)
return page->inuse == page->objects;
}

-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, obj_idx, off;
-
- unsigned int class_idx;
- enum fullness_group fg;
- struct size_class *class;
- struct mapping_area *area;
- struct page *pages[2];
- void *ret;
-
- 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());
-
- /* From now on, migration cannot move the object */
- pin_tag(handle);
-
- obj = handle_to_obj(handle);
- obj_to_location(obj, &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);
- ret = area->vm_addr + off;
- goto out;
- }
-
- /* this object spans two pages */
- pages[0] = page;
- pages[1] = get_next_page(page);
- BUG_ON(!pages[1]);
-
- ret = __zs_map_object(area, pages, off, class->size);
-out:
- if (!class->huge)
- ret += ZS_HANDLE_SIZE;
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(zs_map_object);
-
-void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
-{
- struct page *page;
- unsigned long obj, 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_obj(handle);
- obj_to_location(obj, &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);
- unpin_tag(handle);
-}
-EXPORT_SYMBOL_GPL(zs_unmap_object);
-
static unsigned long obj_malloc(struct page *first_page,
struct size_class *class, unsigned long handle)
{
@@ -1347,63 +1238,6 @@ static unsigned long obj_malloc(struct page *first_page,
return obj;
}

-
-/**
- * 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 handle, obj;
- struct size_class *class;
- struct page *first_page;
-
- if (unlikely(!size || size > ZS_MAX_ALLOC_SIZE))
- return 0;
-
- handle = alloc_handle(pool);
- if (!handle)
- return 0;
-
- /* extra space in chunk to keep the handle */
- size += ZS_HANDLE_SIZE;
- 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)) {
- free_handle(pool, handle);
- 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);
- zs_stat_inc(class, OBJ_ALLOCATED, get_maxobj_per_zspage(
- class->size, class->pages_per_zspage));
- }
-
- obj = obj_malloc(first_page, class, handle);
- /* Now move the zspage to another fullness group, if required */
- fix_fullness_group(class, first_page);
- record_obj(handle, obj);
- spin_unlock(&class->lock);
-
- return handle;
-}
-EXPORT_SYMBOL_GPL(zs_malloc);
-
static void obj_free(struct zs_pool *pool, struct size_class *class,
unsigned long obj)
{
@@ -1436,42 +1270,6 @@ static void obj_free(struct zs_pool *pool, struct size_class *class,
zs_stat_dec(class, OBJ_USED, 1);
}

-void zs_free(struct zs_pool *pool, unsigned long handle)
-{
- struct page *first_page, *f_page;
- unsigned long obj, f_objidx;
- int class_idx;
- struct size_class *class;
- enum fullness_group fullness;
-
- if (unlikely(!handle))
- return;
-
- pin_tag(handle);
- obj = handle_to_obj(handle);
- obj_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];
-
- spin_lock(&class->lock);
- obj_free(pool, class, obj);
- fullness = fix_fullness_group(class, first_page);
- if (fullness == ZS_EMPTY) {
- zs_stat_dec(class, OBJ_ALLOCATED, get_maxobj_per_zspage(
- class->size, class->pages_per_zspage));
- atomic_long_sub(class->pages_per_zspage,
- &pool->pages_allocated);
- free_zspage(first_page);
- }
- spin_unlock(&class->lock);
- unpin_tag(handle);
-
- free_handle(pool, handle);
-}
-EXPORT_SYMBOL_GPL(zs_free);
-
static void zs_object_copy(unsigned long dst, unsigned long src,
struct size_class *class)
{
@@ -1572,13 +1370,17 @@ static unsigned long find_alloced_obj(struct page *page, int index,

struct zs_compact_control {
/* Source page for migration which could be a subpage of zspage. */
- struct page *s_page;
- /* Destination page for migration which should be a first page
- * of zspage. */
- struct page *d_page;
- /* Starting object index within @s_page which used for live object
- * in the subpage. */
- int index;
+ struct page *s_page;
+ /*
+ * Destination page for migration which should be a first page
+ * of zspage.
+ */
+ struct page *d_page;
+ /*
+ * Starting object index within @s_page which used for live object
+ * in the subpage.
+ */
+ int index;
};

static int migrate_zspage(struct zs_pool *pool, struct size_class *class,
@@ -1740,6 +1542,208 @@ static void __zs_compact(struct zs_pool *pool, struct size_class *class)
spin_unlock(&class->lock);
}

+
+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, obj_idx, off;
+
+ unsigned int class_idx;
+ enum fullness_group fg;
+ struct size_class *class;
+ struct mapping_area *area;
+ struct page *pages[2];
+ void *ret;
+
+ 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());
+
+ /* From now on, migration cannot move the object */
+ pin_tag(handle);
+
+ obj = handle_to_obj(handle);
+ obj_to_location(obj, &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);
+ ret = area->vm_addr + off;
+ goto out;
+ }
+
+ /* this object spans two pages */
+ pages[0] = page;
+ pages[1] = get_next_page(page);
+ BUG_ON(!pages[1]);
+
+ ret = __zs_map_object(area, pages, off, class->size);
+out:
+ if (!class->huge)
+ ret += ZS_HANDLE_SIZE;
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(zs_map_object);
+
+void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
+{
+ struct page *page;
+ unsigned long obj, 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_obj(handle);
+ obj_to_location(obj, &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);
+ unpin_tag(handle);
+}
+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 handle, obj;
+ struct size_class *class;
+ struct page *first_page;
+
+ if (unlikely(!size || size > ZS_MAX_ALLOC_SIZE))
+ return 0;
+
+ handle = alloc_handle(pool);
+ if (!handle)
+ return 0;
+
+ /* extra space in chunk to keep the handle */
+ size += ZS_HANDLE_SIZE;
+ 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)) {
+ free_handle(pool, handle);
+ 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);
+ zs_stat_inc(class, OBJ_ALLOCATED, get_maxobj_per_zspage(
+ class->size, class->pages_per_zspage));
+ }
+
+ obj = obj_malloc(first_page, class, handle);
+ /* Now move the zspage to another fullness group, if required */
+ fix_fullness_group(class, first_page);
+ record_obj(handle, obj);
+ spin_unlock(&class->lock);
+
+ return handle;
+}
+EXPORT_SYMBOL_GPL(zs_malloc);
+
+void zs_free(struct zs_pool *pool, unsigned long handle)
+{
+ struct page *first_page, *f_page;
+ unsigned long obj, f_objidx;
+ int class_idx;
+ struct size_class *class;
+ enum fullness_group fullness;
+
+ if (unlikely(!handle))
+ return;
+
+ pin_tag(handle);
+ obj = handle_to_obj(handle);
+ obj_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];
+
+ spin_lock(&class->lock);
+ obj_free(pool, class, obj);
+ fullness = fix_fullness_group(class, first_page);
+ if (fullness == ZS_EMPTY) {
+ zs_stat_dec(class, OBJ_ALLOCATED, get_maxobj_per_zspage(
+ class->size, class->pages_per_zspage));
+ atomic_long_sub(class->pages_per_zspage,
+ &pool->pages_allocated);
+ free_zspage(first_page);
+ }
+ spin_unlock(&class->lock);
+ unpin_tag(handle);
+
+ free_handle(pool, handle);
+}
+EXPORT_SYMBOL_GPL(zs_free);
+
unsigned long zs_compact(struct zs_pool *pool)
{
int i;
--
2.4.2.337.gfae46aa

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