[PATCH 2/2] zram: allow zram to allocate CMA pages

From: Chris Goldsworthy
Date: Mon Nov 02 2020 - 09:40:45 EST


From: Vinayak Menon <vinmenon@xxxxxxxxxxxxxx>

Though zram pages are movable, they aren't allowed to enter
MIGRATE_CMA pageblocks. zram is not seen to pin pages for
long which can cause an issue. Moreover allowing zram to
pick CMA pages can be helpful in cases seen where zram order
0 alloc fails when there are lots of free cma pages, resulting
in kswapd or direct reclaim not making enough progress.

Signed-off-by: Vinayak Menon <vinmenon@xxxxxxxxxxxxxx>
Signed-off-by: Chris Goldsworthy <cgoldswo@xxxxxxxxxxxxxx>
---
drivers/block/zram/zram_drv.c | 5 +++--
mm/zsmalloc.c | 4 ++--
2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 9a1e6ee..4b6b16d 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -1380,13 +1380,14 @@ static int __zram_bvec_write(struct zram *zram, struct bio_vec *bvec,
__GFP_KSWAPD_RECLAIM |
__GFP_NOWARN |
__GFP_HIGHMEM |
- __GFP_MOVABLE);
+ __GFP_MOVABLE |
+ __GFP_CMA);
if (!handle) {
zcomp_stream_put(zram->comp);
atomic64_inc(&zram->stats.writestall);
handle = zs_malloc(zram->mem_pool, comp_len,
GFP_NOIO | __GFP_HIGHMEM |
- __GFP_MOVABLE);
+ __GFP_MOVABLE | __GFP_CMA);
if (handle)
goto compress_again;
return -ENOMEM;
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index b03bee2..16ba318 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -351,7 +351,7 @@ 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));
+ gfp & ~(__GFP_HIGHMEM|__GFP_MOVABLE|__GFP_CMA));
}

static void cache_free_handle(struct zs_pool *pool, unsigned long handle)
@@ -362,7 +362,7 @@ 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));
+ flags & ~(__GFP_HIGHMEM|__GFP_MOVABLE|__GFP_CMA));
}

static void cache_free_zspage(struct zs_pool *pool, struct zspage *zspage)
--
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