[PATCH 1/4] mm/zsmalloc: always set movable/highmem flag to the zspage

From: js1304
Date: Wed Mar 15 2017 - 22:46:56 EST


From: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>

Zspage is always movable and is used through zs_map_object() function
which returns directly accessible pointer that contains content of
zspage. It is independent on the user's allocation flag.
Therefore, it's better to always set movable/highmem flag to the zspage.
After that, we don't need __GFP_MOVABLE/__GFP_HIGHMEM clearing in
cache_alloc_handle()/cache_alloc_zspage() since there is no zs_malloc
caller who specifies __GFP_MOVABLE/__GFP_HIGHMEM.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
---
drivers/block/zram/zram_drv.c | 9 ++-------
mm/zsmalloc.c | 10 ++++------
2 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 0194441..f65dcd1 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -684,19 +684,14 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
*/
if (!handle)
handle = zs_malloc(meta->mem_pool, clen,
- __GFP_KSWAPD_RECLAIM |
- __GFP_NOWARN |
- __GFP_HIGHMEM |
- __GFP_MOVABLE);
+ __GFP_KSWAPD_RECLAIM | __GFP_NOWARN);
if (!handle) {
zcomp_stream_put(zram->comp);
zstrm = NULL;

atomic64_inc(&zram->stats.writestall);

- handle = zs_malloc(meta->mem_pool, clen,
- GFP_NOIO | __GFP_HIGHMEM |
- __GFP_MOVABLE);
+ handle = zs_malloc(meta->mem_pool, clen, GFP_NOIO);
if (handle)
goto compress_again;

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index b7ee9c3..fada232 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -347,8 +347,7 @@ static void destroy_cache(struct zs_pool *pool)

static unsigned long cache_alloc_handle(struct zs_pool *pool, gfp_t gfp)
{
- return (unsigned long)kmem_cache_alloc(pool->handle_cachep,
- gfp & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
+ return (unsigned long)kmem_cache_alloc(pool->handle_cachep, gfp);
}

static void cache_free_handle(struct zs_pool *pool, unsigned long handle)
@@ -358,9 +357,8 @@ static void cache_free_handle(struct zs_pool *pool, unsigned long handle)

static struct zspage *cache_alloc_zspage(struct zs_pool *pool, gfp_t flags)
{
- return kmem_cache_alloc(pool->zspage_cachep,
- flags & ~(__GFP_HIGHMEM|__GFP_MOVABLE));
-}
+ return kmem_cache_alloc(pool->zspage_cachep, flags);
+};

static void cache_free_zspage(struct zs_pool *pool, struct zspage *zspage)
{
@@ -1120,7 +1118,7 @@ static struct zspage *alloc_zspage(struct zs_pool *pool,
for (i = 0; i < class->pages_per_zspage; i++) {
struct page *page;

- page = alloc_page(gfp);
+ page = alloc_page(gfp | __GFP_MOVABLE | __GFP_HIGHMEM);
if (!page) {
while (--i >= 0) {
dec_zone_page_state(pages[i], NR_ZSPAGES);
--
1.9.1