[PATCH 2/3] zpool/zsmalloc/zbud: align on interfaces

Vitaly Wool
2015-09-14T13:51:39Z

As a preparation step for zram to be able to use common zpool API,
there has to be some alignment done on it. This patch adds
functions that correspond to zsmalloc-specific API to the common
zpool API and takes care of the callbacks that have to be
introduced, too.

Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
---
drivers/block/zram/zram_drv.c | 4 ++--
include/linux/zpool.h | 14 ++++++++++++++
include/linux/zsmalloc.h | 8 ++------
mm/zbud.c | 12 ++++++++++++
mm/zpool.c | 22 ++++++++++++++++++++++
mm/zsmalloc.c | 23 ++++++++++++++++++++---
6 files changed, 72 insertions(+), 11 deletions(-)

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 6d9f1d1..49d5a65 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -427,12 +427,12 @@ static ssize_t mm_stat_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct zram *zram = dev_to_zram(dev);
- struct zs_pool_stats pool_stats;
+ struct zpool_stats pool_stats;
u64 orig_size, mem_used = 0;
long max_used;
ssize_t ret;

- memset(&pool_stats, 0x00, sizeof(struct zs_pool_stats));
+ memset(&pool_stats, 0x00, sizeof(struct zpool_stats));

down_read(&zram->init_lock);
if (init_done(zram)) {
diff --git a/include/linux/zpool.h b/include/linux/zpool.h
index 42f8ec9..f64cf86 100644
--- a/include/linux/zpool.h
+++ b/include/linux/zpool.h
@@ -17,6 +17,11 @@ struct zpool_ops {
int (*evict)(struct zpool *pool, unsigned long handle);
};

+struct zpool_stats {
+ /* How many pages were migrated (freed) */
+ unsigned long pages_compacted;
+};
+
/*
* Control how a handle is mapped. It will be ignored if the
* implementation does not support it. Its use is optional.
@@ -58,6 +63,10 @@ void *zpool_map_handle(struct zpool *pool, unsigned long handle,

void zpool_unmap_handle(struct zpool *pool, unsigned long handle);

+int zpool_compact(struct zpool *pool, unsigned long *compacted);
+
+void zpool_stats(struct zpool *pool, struct zpool_stats *zstats);
+
u64 zpool_get_total_size(struct zpool *pool);

@@ -72,6 +81,8 @@ u64 zpool_get_total_size(struct zpool *pool);
* @shrink: shrink the pool.
* @map: map a handle.
* @unmap: unmap a handle.
+ * @compact: try to run compaction for the pool
+ * @stats: get statistics for the pool
* @total_size: get total size of a pool.
*
* This is created by a zpool implementation and registered
@@ -98,6 +109,9 @@ struct zpool_driver {
enum zpool_mapmode mm);
void (*unmap)(void *pool, unsigned long handle);

+ int (*compact)(void *pool, unsigned long *compacted);
+ void (*stats)(void *pool, struct zpool_stats *stats);
+
u64 (*total_size)(void *pool);
};

diff --git a/include/linux/zsmalloc.h b/include/linux/zsmalloc.h
index 6398dfa..5aee1c7 100644
--- a/include/linux/zsmalloc.h
+++ b/include/linux/zsmalloc.h
@@ -15,6 +15,7 @@
#define _ZS_MALLOC_H_

#include <linux/types.h>
+#include <linux/zpool.h>

/*
* zsmalloc mapping modes
@@ -34,11 +35,6 @@ enum zs_mapmode {
*/
};

-struct zs_pool_stats {
- /* How many pages were migrated (freed) */
- unsigned long pages_compacted;
-};
-
struct zs_pool;

struct zs_pool *zs_create_pool(char *name, gfp_t flags);
@@ -54,5 +50,5 @@ void zs_unmap_object(struct zs_pool *pool, unsigned long handle);
unsigned long zs_get_total_pages(struct zs_pool *pool);
unsigned long zs_compact(struct zs_pool *pool);

-void zs_pool_stats(struct zs_pool *pool, struct zs_pool_stats *stats);
+void zs_pool_stats(struct zs_pool *pool, struct zpool_stats *stats);
#endif
diff --git a/mm/zbud.c b/mm/zbud.c
index fa48bcdf..0963342 100644
--- a/mm/zbud.c
+++ b/mm/zbud.c
@@ -195,6 +195,16 @@ static void zbud_zpool_unmap(void *pool, unsigned long handle)
zbud_unmap(pool, handle);
}

+static int zbud_zpool_compact(void *pool, unsigned long *compacted)
+{
+ return -EINVAL;
+}
+
+static void zbud_zpool_stats(void *pool, struct zpool_stats *stats)
+{
+ /* no-op */
+}
+
static u64 zbud_zpool_total_size(void *pool)
{
return zbud_get_pool_size(pool) * PAGE_SIZE;
@@ -210,6 +220,8 @@ static struct zpool_driver zbud_zpool_driver = {
.shrink = zbud_zpool_shrink,
.map = zbud_zpool_map,
.unmap = zbud_zpool_unmap,
+ .compact = zbud_zpool_compact,
+ .stats = zbud_zpool_stats,
.total_size = zbud_zpool_total_size,
};

diff --git a/mm/zpool.c b/mm/zpool.c
index 8f670d3..15a171a 100644
--- a/mm/zpool.c
+++ b/mm/zpool.c
@@ -341,6 +341,28 @@ void zpool_unmap_handle(struct zpool *zpool, unsigned long handle)
}

/**
+ * zpool_compact() - try to run compaction over zpool
+ * @pool The zpool to compact
+ * @compacted The number of migrated pages
+ *
+ * Returns: 0 on success, error code otherwise
+ */
+int zpool_compact(struct zpool *zpool, unsigned long *compacted)
+{
+ return zpool->driver->compact(zpool->pool, compacted);
+}
+
+/**
+ * zpool_stats() - obtain zpool statistics
+ * @pool The zpool to get statistics for
+ * @zstats stats to fill in
+ */
+void zpool_stats(struct zpool *zpool, struct zpool_stats *zstats)
+{
+ zpool->driver->stats(zpool->pool, zstats);
+}
+
+/**
* zpool_get_total_size() - The total size of the pool
* @pool The zpool to check
*
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index f135b1b..f002f57 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -245,7 +245,7 @@ struct zs_pool {
gfp_t flags; /* allocation flags used when growing pool */
atomic_long_t pages_allocated;

- struct zs_pool_stats stats;
+ struct zpool_stats stats;

/* Compact classes */
struct shrinker shrinker;
@@ -365,6 +365,21 @@ static void zs_zpool_unmap(void *pool, unsigned long handle)
zs_unmap_object(pool, handle);
}

+static int zs_zpool_compact(void *pool, unsigned long *compacted)
+{
+ unsigned long c = zs_compact(pool);
+
+ if (compacted)
+ *compacted = c;
+ return 0;
+}
+
+
+static void zs_zpool_stats(void *pool, struct zpool_stats *stats)
+{
+ zs_pool_stats(pool, stats);
+}
+
static u64 zs_zpool_total_size(void *pool)
{
return zs_get_total_pages(pool) << PAGE_SHIFT;
@@ -380,6 +395,8 @@ static struct zpool_driver zs_zpool_driver = {
.shrink = zs_zpool_shrink,
.map = zs_zpool_map,
.unmap = zs_zpool_unmap,
+ .compact = zs_zpool_compact,
+ .stats = zs_zpool_stats,
.total_size = zs_zpool_total_size,
};

@@ -1789,9 +1806,9 @@ unsigned long zs_compact(struct zs_pool *pool)
}
EXPORT_SYMBOL_GPL(zs_compact);

-void zs_pool_stats(struct zs_pool *pool, struct zs_pool_stats *stats)
+void zs_pool_stats(struct zs_pool *pool, struct zpool_stats *stats)
{
- memcpy(stats, &pool->stats, sizeof(struct zs_pool_stats));
+ memcpy(stats, &pool->stats, sizeof(struct zpool_stats));
}
EXPORT_SYMBOL_GPL(zs_pool_stats);

--
1.9.1