From d0d8da2dc49dfdfe1d788eaf4d55eb5d4964d926 Mon Sep 17 00:00:00 2001
From: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Date: Fri, 20 May 2016 16:59:48 -0700
Subject: [PATCH] zsmalloc: require GFP in zs_malloc()
Pass GFP flags to zs_malloc() instead of using a fixed mask supplied to
zs_create_pool(), so we can be more flexible, but, more importantly, we
need this to switch zram to per-cpu compression streams -- zram will try
to allocate handle with preemption disabled in a fast path and switch to
a slow path (using different gfp mask) if the fast one has failed.
Apart from that, this also align zs_malloc() interface with zspool/zbud.
[sergey.senozhatsky@gmail.com: pass GFP flags to zs_malloc() instead of using a fixed mask]
Link: http://lkml.kernel.org/r/20160429150942.GA637@swordfish
Link: http://lkml.kernel.org/r/20160429150942.GA637@swordfish
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
drivers/block/zram/zram_drv.c | 4 ++--
include/linux/zsmalloc.h | 4 ++--
mm/zsmalloc.c | 24 +++++++++++++-----------
3 files changed, 17 insertions(+), 15 deletions(-)
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 370c2f76016d..b09acdb753ee 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -514,7 +514,7 @@ static struct zram_meta *zram_meta_alloc(char *pool_name, u64 disksize)
goto out_error;
}
- meta->mem_pool = zs_create_pool(pool_name, GFP_NOIO | __GFP_HIGHMEM);
+ meta->mem_pool = zs_create_pool(pool_name);
if (!meta->mem_pool) {
pr_err("Error creating memory pool\n");
goto out_error;
@@ -717,7 +717,7 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
src = uncmem;
}
- handle = zs_malloc(meta->mem_pool, clen);
+ handle = zs_malloc(meta->mem_pool, clen, GFP_NOIO | __GFP_HIGHMEM);
if (!handle) {
pr_err("Error allocating memory for compressed page: %u, size=%zu\n",
index, clen);
diff --git a/include/linux/zsmalloc.h b/include/linux/zsmalloc.h
index 34eb16098a33..57a8e98f2708 100644
--- a/include/linux/zsmalloc.h
+++ b/include/linux/zsmalloc.h
@@ -41,10 +41,10 @@ struct zs_pool_stats {
struct zs_pool;
-struct zs_pool *zs_create_pool(const char *name, gfp_t flags);
+struct zs_pool *zs_create_pool(const char *name);
void zs_destroy_pool(struct zs_pool *pool);
-unsigned long zs_malloc(struct zs_pool *pool, size_t size);
+unsigned long zs_malloc(struct zs_pool *pool, size_t size, gfp_t flags);
void zs_free(struct zs_pool *pool, unsigned long obj);
void *zs_map_object(struct zs_pool *pool, unsigned long handle,
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index ae288c9f7156..aba39a291523 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -247,7 +247,6 @@ struct zs_pool {
struct size_class **size_class;
struct kmem_cache *handle_cachep;
- gfp_t flags; /* allocation flags used when growing pool */
atomic_long_t pages_allocated;
struct zs_pool_stats stats;
@@ -295,10 +294,10 @@ static void destroy_handle_cache(struct zs_pool *pool)
kmem_cache_destroy(pool->handle_cachep);
}
-static unsigned long alloc_handle(struct zs_pool *pool)
+static unsigned long alloc_handle(struct zs_pool *pool, gfp_t gfp)
{
return (unsigned long)kmem_cache_alloc(pool->handle_cachep,
- pool->flags & ~__GFP_HIGHMEM);
+ gfp & ~__GFP_HIGHMEM);
}
static void free_handle(struct zs_pool *pool, unsigned long handle)
@@ -324,7 +323,12 @@ static void *zs_zpool_create(const char *name, gfp_t gfp,
const struct zpool_ops *zpool_ops,
struct zpool *zpool)
{
- return zs_create_pool(name, gfp);
+ /*
+ * Ignore global gfp flags: zs_malloc() may be invoked from
+ * different contexts and its caller must provide a valid
+ * gfp mask.
+ */
+ return zs_create_pool(name);
}
static void zs_zpool_destroy(void *pool)
@@ -335,7 +339,7 @@ static void zs_zpool_destroy(void *pool)
static int zs_zpool_malloc(void *pool, size_t size, gfp_t gfp,
unsigned long *handle)
{
- *handle = zs_malloc(pool, size);
+ *handle = zs_malloc(pool, size, gfp);
return *handle ? 0 : -1;
}
static void zs_zpool_free(void *pool, unsigned long handle)
@@ -1391,7 +1395,7 @@ static unsigned long obj_malloc(struct size_class *class,
* otherwise 0.
* Allocation requests with size > ZS_MAX_ALLOC_SIZE will fail.
*/
-unsigned long zs_malloc(struct zs_pool *pool, size_t size)
+unsigned long zs_malloc(struct zs_pool *pool, size_t size, gfp_t gfp)
{
unsigned long handle, obj;
struct size_class *class;
@@ -1400,7 +1404,7 @@ unsigned long zs_malloc(struct zs_pool *pool, size_t size)
if (unlikely(!size || size > ZS_MAX_ALLOC_SIZE))
return 0;
- handle = alloc_handle(pool);
+ handle = alloc_handle(pool, gfp);
if (!handle)
return 0;
@@ -1413,7 +1417,7 @@ unsigned long zs_malloc(struct zs_pool *pool, size_t size)
if (!first_page) {
spin_unlock(&class->lock);
- first_page = alloc_zspage(class, pool->flags);
+ first_page = alloc_zspage(class, gfp);
if (unlikely(!first_page)) {
free_handle(pool, handle);
return 0;
@@ -1878,7 +1882,7 @@ static int zs_register_shrinker(struct zs_pool *pool)
* On success, a pointer to the newly created pool is returned,
* otherwise NULL.
*/
-struct zs_pool *zs_create_pool(const char *name, gfp_t flags)
+struct zs_pool *zs_create_pool(const char *name)
{
int i;
struct zs_pool *pool;
@@ -1948,8 +1952,6 @@ struct zs_pool *zs_create_pool(const char *name, gfp_t flags)
prev_class = class;
}
- pool->flags = flags;
-
if (zs_pool_stat_create(pool, name))
goto err;