lkml.org 
[lkml]   [2016]   [Mar]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v1 09/19] zsmalloc: keep max_object in size_class
From
Date


On 2016/3/11 15:30, Minchan Kim wrote:
> Every zspage in a size_class has same number of max objects so
> we could move it to a size_class.
>
> Signed-off-by: Minchan Kim <minchan@kernel.org>
> ---
> mm/zsmalloc.c | 29 ++++++++++++++---------------
> 1 file changed, 14 insertions(+), 15 deletions(-)
>
> diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
> index b4fb11831acb..ca663c82c1fc 100644
> --- a/mm/zsmalloc.c
> +++ b/mm/zsmalloc.c
> @@ -32,8 +32,6 @@
> * page->freelist: points to the first free object in zspage.
> * Free objects are linked together using in-place
> * metadata.
> - * page->objects: maximum number of objects we can store in this
> - * zspage (class->zspage_order * PAGE_SIZE / class->size)
> * page->lru: links together first pages of various zspages.
> * Basically forming list of zspages in a fullness group.
> * page->mapping: class index and fullness group of the zspage
> @@ -211,6 +209,7 @@ struct size_class {
> * of ZS_ALIGN.
> */
> int size;
> + int objs_per_zspage;
> unsigned int index;
>
> struct zs_size_stat stats;
> @@ -622,21 +621,22 @@ static inline void zs_pool_stat_destroy(struct zs_pool *pool)
> * the pool (not yet implemented). This function returns fullness
> * status of the given page.
> */
> -static enum fullness_group get_fullness_group(struct page *first_page)
> +static enum fullness_group get_fullness_group(struct size_class *class,
> + struct page *first_page)
> {
> - int inuse, max_objects;
> + int inuse, objs_per_zspage;
> enum fullness_group fg;
>
> VM_BUG_ON_PAGE(!is_first_page(first_page), first_page);
>
> inuse = first_page->inuse;
> - max_objects = first_page->objects;
> + objs_per_zspage = class->objs_per_zspage;
>
> if (inuse == 0)
> fg = ZS_EMPTY;
> - else if (inuse == max_objects)
> + else if (inuse == objs_per_zspage)
> fg = ZS_FULL;
> - else if (inuse <= 3 * max_objects / fullness_threshold_frac)
> + else if (inuse <= 3 * objs_per_zspage / fullness_threshold_frac)
> fg = ZS_ALMOST_EMPTY;
> else
> fg = ZS_ALMOST_FULL;
> @@ -723,7 +723,7 @@ static enum fullness_group fix_fullness_group(struct size_class *class,
> enum fullness_group currfg, newfg;
>
> get_zspage_mapping(first_page, &class_idx, &currfg);
> - newfg = get_fullness_group(first_page);
> + newfg = get_fullness_group(class, first_page);
> if (newfg == currfg)
> goto out;
>
> @@ -1003,9 +1003,6 @@ static struct page *alloc_zspage(struct size_class *class, gfp_t flags)
> init_zspage(class, first_page);
>
> first_page->freelist = location_to_obj(first_page, 0);
> - /* Maximum number of objects we can store in this zspage */
> - first_page->objects = class->pages_per_zspage * PAGE_SIZE / class->size;
> -
> error = 0; /* Success */
>
> cleanup:
> @@ -1235,11 +1232,11 @@ static bool can_merge(struct size_class *prev, int size, int pages_per_zspage)
> return true;
> }
>
> -static bool zspage_full(struct page *first_page)
> +static bool zspage_full(struct size_class *class, struct page *first_page)
> {
> VM_BUG_ON_PAGE(!is_first_page(first_page), first_page);
>
> - return first_page->inuse == first_page->objects;
> + return first_page->inuse == class->objs_per_zspage;
> }
>
> unsigned long zs_get_total_pages(struct zs_pool *pool)
> @@ -1625,7 +1622,7 @@ static int migrate_zspage(struct zs_pool *pool, struct size_class *class,
> }
>
> /* Stop if there is no more space */
> - if (zspage_full(d_page)) {
> + if (zspage_full(class, d_page)) {
> unpin_tag(handle);
> ret = -ENOMEM;
> break;
> @@ -1684,7 +1681,7 @@ static enum fullness_group putback_zspage(struct zs_pool *pool,
> {
> enum fullness_group fullness;
>
> - fullness = get_fullness_group(first_page);
> + fullness = get_fullness_group(class, first_page);
> insert_zspage(class, fullness, first_page);
> set_zspage_mapping(first_page, class->index, fullness);
>
> @@ -1933,6 +1930,8 @@ struct zs_pool *zs_create_pool(const char *name, gfp_t flags)
> class->size = size;
> class->index = i;
> class->pages_per_zspage = pages_per_zspage;
> + class->objs_per_zspage = class->pages_per_zspage *
> + PAGE_SIZE / class->size;
> if (pages_per_zspage == 1 &&
> get_maxobj_per_zspage(size, pages_per_zspage) == 1)
> class->huge = true;

computes the "objs_per_zspage" twice here.

class->objs_per_zspage = get_maxobj_per_zspage(size,
pages_per_zspage);
if (pages_per_zspage == 1 && class->objs_per_zspage ==1)
class->huge = true;

>

\
 
 \ /
  Last update: 2016-03-12 03:01    [W:0.483 / U:0.268 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site