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()
Signed-off-by: Ganesh Mahendran <opensource.ganesh@xxxxxxxxx>
---
mm/zsmalloc.c | 374 ++++++++++++++++++++++++++++-----------------------------
1 file changed, 187 insertions(+), 187 deletions(-)
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index 4d0a063..b724039 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -884,19 +884,6 @@ 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);
@@ -914,40 +901,28 @@ static int zs_register_cpu_notifier(void)
return notifier_to_errno(ret);
}
-static void init_zs_size_classes(void)
+static void zs_unregister_cpu_notifier(void)
{
- int nr;
+ int cpu;
- nr = (ZS_MAX_ALLOC_SIZE - ZS_MIN_ALLOC_SIZE) / ZS_SIZE_CLASS_DELTA + 1;
- if ((ZS_MAX_ALLOC_SIZE - ZS_MIN_ALLOC_SIZE) % ZS_SIZE_CLASS_DELTA)
- nr += 1;
+ cpu_notifier_register_begin();
- zs_size_classes = nr;
-}
+ for_each_online_cpu(cpu)
+ zs_cpu_notifier(NULL, CPU_DEAD, (void *)(long)cpu);
+ __unregister_cpu_notifier(&zs_cpu_nb);
-static void __exit zs_exit(void)
-{
-#ifdef CONFIG_ZPOOL
- zpool_unregister_driver(&zs_zpool_driver);
-#endif
- zs_unregister_cpu_notifier();
+ cpu_notifier_register_done();
}
-static int __init zs_init(void)
+static void init_zs_size_classes(void)
{
- int ret = zs_register_cpu_notifier();
-
- if (ret) {
- zs_unregister_cpu_notifier();
- return ret;
- }
+ int nr;
- init_zs_size_classes();
+ nr = (ZS_MAX_ALLOC_SIZE - ZS_MIN_ALLOC_SIZE) / ZS_SIZE_CLASS_DELTA + 1;
+ if ((ZS_MAX_ALLOC_SIZE - ZS_MIN_ALLOC_SIZE) % ZS_SIZE_CLASS_DELTA)
+ nr += 1;
-#ifdef CONFIG_ZPOOL
- zpool_register_driver(&zs_zpool_driver);
-#endif
- return 0;
+ zs_size_classes = nr;
}
static unsigned int get_maxobj_per_zspage(int size, int pages_per_zspage)
@@ -967,113 +942,101 @@ 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_create_pool - Creates an allocation pool to work from.
- * @flags: allocation flags used to allocate pool metadata
+ * zs_map_object - get address of allocated object from handle.
+ * @pool: pool from which the object was allocated
+ * @handle: handle returned from zs_malloc
*
- * This function must be called before anything when using
- * the zsmalloc allocator.
+ * 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.
*
- * On success, a pointer to the newly created pool is returned,
- * otherwise NULL.
+ * 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.
*/
-struct zs_pool *zs_create_pool(gfp_t flags)
+void *zs_map_object(struct zs_pool *pool, unsigned long handle,
+ enum zs_mapmode mm)
{
- int i;
- struct zs_pool *pool;
- struct size_class *prev_class = NULL;
+ struct page *page;
+ unsigned long obj_idx, off;
- pool = kzalloc(sizeof(*pool), GFP_KERNEL);
- if (!pool)
- return NULL;
+ unsigned int class_idx;
+ enum fullness_group fg;
+ struct size_class *class;
+ struct mapping_area *area;
+ struct page *pages[2];
- pool->size_class = kcalloc(zs_size_classes, sizeof(struct size_class *),
- GFP_KERNEL);
- if (!pool->size_class) {
- kfree(pool);
- return NULL;
- }
+ BUG_ON(!handle);
/*
- * Iterate reversly, because, size of size_class that we want to use
- * for merging should be larger or equal to current size.
+ * 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.
*/
- for (i = zs_size_classes - 1; i >= 0; i--) {
- int size;
- int pages_per_zspage;
- struct size_class *class;
-
- size = ZS_MIN_ALLOC_SIZE + i * ZS_SIZE_CLASS_DELTA;
- if (size > ZS_MAX_ALLOC_SIZE)
- size = ZS_MAX_ALLOC_SIZE;
- pages_per_zspage = get_pages_per_zspage(size);
-
- /*
- * size_class is used for normal zsmalloc operation such
- * as alloc/free for that size. Although it is natural that we
- * have one size_class for each size, there is a chance that we
- * can get more memory utilization if we use one size_class for
- * many different sizes whose size_class have same
- * characteristics. So, we makes size_class point to
- * previous size_class if possible.
- */
- if (prev_class) {
- if (can_merge(prev_class, size, pages_per_zspage)) {
- pool->size_class[i] = prev_class;
- continue;
- }
- }
-
- class = kzalloc(sizeof(struct size_class), GFP_KERNEL);
- if (!class)
- goto err;
+ BUG_ON(in_interrupt());
- class->size = size;
- class->index = i;
- class->pages_per_zspage = pages_per_zspage;
- spin_lock_init(&class->lock);
- pool->size_class[i] = class;
+ 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);
- prev_class = class;
+ 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;
}
- pool->flags = flags;
-
- return pool;
+ /* this object spans two pages */
+ pages[0] = page;
+ pages[1] = get_next_page(page);
+ BUG_ON(!pages[1]);
-err:
- zs_destroy_pool(pool);
- return NULL;
+ return __zs_map_object(area, pages, off, class->size);
}
-EXPORT_SYMBOL_GPL(zs_create_pool);
+EXPORT_SYMBOL_GPL(zs_map_object);
-void zs_destroy_pool(struct zs_pool *pool)
+void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
{
- int i;
+ struct page *page;
+ unsigned long obj_idx, off;
- for (i = 0; i < zs_size_classes; i++) {
- int fg;
- struct size_class *class = pool->size_class[i];
+ unsigned int class_idx;
+ enum fullness_group fg;
+ struct size_class *class;
+ struct mapping_area *area;
- if (!class)
- continue;
+ BUG_ON(!handle);
- if (class->index != i)
- continue;
+ 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);
- for (fg = 0; fg < _ZS_NR_FULLNESS_GROUPS; fg++) {
- if (class->fullness_list[fg]) {
- pr_info("Freeing non-empty class with size %db, fullness group %d\n",
- class->size, fg);
- }
- }
- kfree(class);
- }
+ area = this_cpu_ptr(&zs_map_area);
+ if (off + class->size <= PAGE_SIZE)
+ kunmap_atomic(area->vm_addr);
+ else {
+ struct page *pages[2];
- kfree(pool->size_class);
- kfree(pool);
+ 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_destroy_pool);
+EXPORT_SYMBOL_GPL(zs_unmap_object);
/**
* zs_malloc - Allocate block of given size from pool.
@@ -1176,100 +1139,137 @@ void zs_free(struct zs_pool *pool, unsigned long obj)
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.
+ * zs_create_pool - Creates an allocation pool to work from.
+ * @flags: allocation flags used to allocate pool metadata
*
- * Only one object can be mapped per cpu at a time. There is no protection
- * against nested mappings.
+ * This function must be called before anything when using
+ * the zsmalloc allocator.
*
- * This function returns with preemption and page faults disabled.
+ * On success, a pointer to the newly created pool is returned,
+ * otherwise NULL.
*/
-void *zs_map_object(struct zs_pool *pool, unsigned long handle,
- enum zs_mapmode mm)
+struct zs_pool *zs_create_pool(gfp_t flags)
{
- struct page *page;
- unsigned long obj_idx, off;
+ int i;
+ struct zs_pool *pool;
+ struct size_class *prev_class = NULL;
- unsigned int class_idx;
- enum fullness_group fg;
- struct size_class *class;
- struct mapping_area *area;
- struct page *pages[2];
+ pool = kzalloc(sizeof(*pool), GFP_KERNEL);
+ if (!pool)
+ return NULL;
- BUG_ON(!handle);
+ pool->size_class = kcalloc(zs_size_classes, sizeof(struct size_class *),
+ GFP_KERNEL);
+ if (!pool->size_class) {
+ kfree(pool);
+ return NULL;
+ }
/*
- * 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.
+ * Iterate reversly, because, size of size_class that we want to use
+ * for merging should be larger or equal to current size.
*/
- BUG_ON(in_interrupt());
+ for (i = zs_size_classes - 1; i >= 0; i--) {
+ int size;
+ int pages_per_zspage;
+ struct size_class *class;
- 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);
+ size = ZS_MIN_ALLOC_SIZE + i * ZS_SIZE_CLASS_DELTA;
+ if (size > ZS_MAX_ALLOC_SIZE)
+ size = ZS_MAX_ALLOC_SIZE;
+ pages_per_zspage = get_pages_per_zspage(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;
+ /*
+ * size_class is used for normal zsmalloc operation such
+ * as alloc/free for that size. Although it is natural that we
+ * have one size_class for each size, there is a chance that we
+ * can get more memory utilization if we use one size_class for
+ * many different sizes whose size_class have same
+ * characteristics. So, we makes size_class point to
+ * previous size_class if possible.
+ */
+ if (prev_class) {
+ if (can_merge(prev_class, size, pages_per_zspage)) {
+ pool->size_class[i] = prev_class;
+ continue;
+ }
+ }
+
+ class = kzalloc(sizeof(struct size_class), GFP_KERNEL);
+ if (!class)
+ goto err;
+
+ class->size = size;
+ class->index = i;
+ class->pages_per_zspage = pages_per_zspage;
+ spin_lock_init(&class->lock);
+ pool->size_class[i] = class;
+
+ prev_class = class;
}
- /* this object spans two pages */
- pages[0] = page;
- pages[1] = get_next_page(page);
- BUG_ON(!pages[1]);
+ pool->flags = flags;
- return __zs_map_object(area, pages, off, class->size);
+ return pool;
+
+err:
+ zs_destroy_pool(pool);
+ return NULL;
}
-EXPORT_SYMBOL_GPL(zs_map_object);
+EXPORT_SYMBOL_GPL(zs_create_pool);
-void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
+void zs_destroy_pool(struct zs_pool *pool)
{
- struct page *page;
- unsigned long obj_idx, off;
+ int i;
- unsigned int class_idx;
- enum fullness_group fg;
- struct size_class *class;
- struct mapping_area *area;
+ for (i = 0; i < zs_size_classes; i++) {
+ int fg;
+ struct size_class *class = pool->size_class[i];
- BUG_ON(!handle);
+ if (!class)
+ continue;
- 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);
+ if (class->index != i)
+ continue;
- area = this_cpu_ptr(&zs_map_area);
- if (off + class->size <= PAGE_SIZE)
- kunmap_atomic(area->vm_addr);
- else {
- struct page *pages[2];
+ for (fg = 0; fg < _ZS_NR_FULLNESS_GROUPS; fg++) {
+ if (class->fullness_list[fg]) {
+ pr_info("Freeing non-empty class with size %db, fullness group %d\n",
+ class->size, fg);
+ }
+ }
+ kfree(class);
+ }
- pages[0] = page;
- pages[1] = get_next_page(page);
- BUG_ON(!pages[1]);
+ kfree(pool->size_class);
+ kfree(pool);
+}
+EXPORT_SYMBOL_GPL(zs_destroy_pool);
- __zs_unmap_object(area, pages, off, class->size);
+static int __init zs_init(void)
+{
+ int ret = zs_register_cpu_notifier();
+
+ if (ret) {
+ zs_unregister_cpu_notifier();
+ return ret;
}
- put_cpu_var(zs_map_area);
+
+ init_zs_size_classes();
+
+#ifdef CONFIG_ZPOOL
+ zpool_register_driver(&zs_zpool_driver);
+#endif
+ return 0;
}
-EXPORT_SYMBOL_GPL(zs_unmap_object);
-unsigned long zs_get_total_pages(struct zs_pool *pool)
+static void __exit zs_exit(void)
{
- return atomic_long_read(&pool->pages_allocated);
+#ifdef CONFIG_ZPOOL
+ zpool_unregister_driver(&zs_zpool_driver);
+#endif
+ zs_unregister_cpu_notifier();
}
-EXPORT_SYMBOL_GPL(zs_get_total_pages);
module_init(zs_init);
module_exit(zs_exit);
--
1.7.9.5
--
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