diff options
Diffstat (limited to 'mm/zsmalloc.c')
| -rw-r--r-- | mm/zsmalloc.c | 54 |
1 files changed, 42 insertions, 12 deletions
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index 3bd8b0a..95771c7 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -57,6 +57,8 @@ * * page->private (union with page->first_page): refers to the * component page after the first page + * If the page is first_page for huge object, it stores handle. + * Look at size_class->huge. * page->freelist: points to the first free object in zspage. * Free objects are linked together using in-place * metadata. @@ -163,7 +165,7 @@ #define ZS_MIN_ALLOC_SIZE \ MAX(32, (ZS_MAX_PAGES_PER_ZSPAGE << PAGE_SHIFT >> OBJ_INDEX_BITS)) /* each chunk includes extra space to keep handle */ -#define ZS_MAX_ALLOC_SIZE (PAGE_SIZE + ZS_HANDLE_SIZE) +#define ZS_MAX_ALLOC_SIZE PAGE_SIZE /* * On systems with 4K page size, this gives 255 size classes! There is a @@ -239,6 +241,8 @@ struct size_class { /* Number of PAGE_SIZE sized pages to combine to form a 'zspage' */ int pages_per_zspage; + /* huge object: pages_per_zspage == 1 && maxobj_per_zspage == 1 */ + bool huge; #ifdef CONFIG_ZSMALLOC_STAT struct zs_size_stat stats; @@ -300,6 +304,7 @@ struct mapping_area { #endif char *vm_addr; /* address of kmap_atomic()'ed pages */ enum zs_mapmode vm_mm; /* mapping mode */ + bool huge; }; static int create_handle_cache(struct zs_pool *pool) @@ -457,7 +462,7 @@ static int get_size_class_index(int size) idx = DIV_ROUND_UP(size - ZS_MIN_ALLOC_SIZE, ZS_SIZE_CLASS_DELTA); - return idx; + return min(zs_size_classes - 1, idx); } /* @@ -666,9 +671,14 @@ static unsigned long handle_to_obj(unsigned long handle) return *(unsigned long *)handle; } -unsigned long obj_to_head(void *obj) +static unsigned long obj_to_head(struct size_class *class, struct page *page, + void *obj) { - return *(unsigned long *)obj; + if (class->huge) { + VM_BUG_ON(!is_first_page(page)); + return *(unsigned long *)page_private(page); + } else + return *(unsigned long *)obj; } static unsigned long obj_idx_to_offset(struct page *page, @@ -954,9 +964,12 @@ static void __zs_unmap_object(struct mapping_area *area, if (area->vm_mm == ZS_MM_RO) goto out; - buf = area->vm_buf + ZS_HANDLE_SIZE; - size -= ZS_HANDLE_SIZE; - off += ZS_HANDLE_SIZE; + buf = area->vm_buf; + if (!area->huge) { + buf = buf + ZS_HANDLE_SIZE; + size -= ZS_HANDLE_SIZE; + off += ZS_HANDLE_SIZE; + } sizes[0] = PAGE_SIZE - off; sizes[1] = size - sizes[0]; @@ -1295,7 +1308,10 @@ void *zs_map_object(struct zs_pool *pool, unsigned long handle, ret = __zs_map_object(area, pages, off, class->size); out: - return ret + ZS_HANDLE_SIZE; + if (!class->huge) + ret += ZS_HANDLE_SIZE; + + return ret; } EXPORT_SYMBOL_GPL(zs_map_object); @@ -1352,8 +1368,12 @@ static unsigned long obj_malloc(struct page *first_page, vaddr = kmap_atomic(m_page); link = (struct link_free *)vaddr + m_offset / sizeof(*link); first_page->freelist = link->next; - /* record handle in the header of allocated chunk */ - link->handle = handle; + if (!class->huge) + /* record handle in the header of allocated chunk */ + link->handle = handle; + else + /* record handle in first_page->private */ + set_page_private(first_page, handle); kunmap_atomic(vaddr); first_page->inuse++; zs_stat_inc(class, OBJ_USED, 1); @@ -1377,7 +1397,7 @@ unsigned long zs_malloc(struct zs_pool *pool, size_t size) struct size_class *class; struct page *first_page; - if (unlikely(!size || (size + ZS_HANDLE_SIZE) > ZS_MAX_ALLOC_SIZE)) + if (unlikely(!size || size > ZS_MAX_ALLOC_SIZE)) return 0; handle = alloc_handle(pool); @@ -1387,6 +1407,11 @@ unsigned long zs_malloc(struct zs_pool *pool, size_t size) /* extra space in chunk to keep the handle */ size += ZS_HANDLE_SIZE; class = pool->size_class[get_size_class_index(size)]; + /* In huge class size, we store the handle into first_page->private */ + if (class->huge) { + size -= ZS_HANDLE_SIZE; + class = pool->size_class[get_size_class_index(size)]; + } spin_lock(&class->lock); first_page = find_get_zspage(class); @@ -1442,6 +1467,8 @@ static void obj_free(struct zs_pool *pool, struct size_class *class, /* Insert this object in containing zspage's freelist */ link = (struct link_free *)(vaddr + f_offset); link->next = first_page->freelist; + if (class->huge) + set_page_private(first_page, 0); kunmap_atomic(vaddr); first_page->freelist = (void *)obj; first_page->inuse--; @@ -1567,7 +1594,7 @@ static unsigned long find_alloced_obj(struct page *page, int index, offset += class->size * index; while (offset < PAGE_SIZE) { - head = obj_to_head(addr + offset); + head = obj_to_head(class, page, addr + offset); if (head & OBJ_ALLOCATED_TAG) { handle = head & ~OBJ_ALLOCATED_TAG; if (trypin_tag(handle)) @@ -1837,6 +1864,9 @@ struct zs_pool *zs_create_pool(char *name, gfp_t flags) class->size = size; class->index = i; class->pages_per_zspage = pages_per_zspage; + if (pages_per_zspage == 1 && + get_maxobj_per_zspage(size, pages_per_zspage) == 1) + class->huge = true; spin_lock_init(&class->lock); pool->size_class[i] = class; |
