diff options
| -rw-r--r-- | mm/zsmalloc.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index b7b4a5612ec7..27b9661c8fa6 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -246,6 +246,14 @@ struct zs_pool { atomic_long_t pages_allocated; struct zs_pool_stats stats; + + /* Compact classes */ + struct shrinker shrinker; + /* + * To signify that register_shrinker() was successful + * and unregister_shrinker() will not Oops. + */ + bool shrinker_enabled; #ifdef CONFIG_ZSMALLOC_STAT struct dentry *stat_dentry; #endif @@ -1778,6 +1786,69 @@ void zs_pool_stats(struct zs_pool *pool, struct zs_pool_stats *stats) } EXPORT_SYMBOL_GPL(zs_pool_stats); +static unsigned long zs_shrinker_scan(struct shrinker *shrinker, + struct shrink_control *sc) +{ + unsigned long pages_freed; + struct zs_pool *pool = container_of(shrinker, struct zs_pool, + shrinker); + + pages_freed = pool->stats.pages_compacted; + /* + * Compact classes and calculate compaction delta. + * Can run concurrently with a manually triggered + * (by user) compaction. + */ + pages_freed = zs_compact(pool) - pages_freed; + + return pages_freed ? pages_freed : SHRINK_STOP; +} + +static unsigned long zs_shrinker_count(struct shrinker *shrinker, + struct shrink_control *sc) +{ + int i; + struct size_class *class; + unsigned long pages_to_free = 0; + struct zs_pool *pool = container_of(shrinker, struct zs_pool, + shrinker); + + if (!pool->shrinker_enabled) + return 0; + + for (i = zs_size_classes - 1; i >= 0; i--) { + class = pool->size_class[i]; + if (!class) + continue; + if (class->index != i) + continue; + + spin_lock(&class->lock); + pages_to_free += zs_can_compact(class); + spin_unlock(&class->lock); + } + + return pages_to_free; +} + +static void zs_unregister_shrinker(struct zs_pool *pool) +{ + if (pool->shrinker_enabled) { + unregister_shrinker(&pool->shrinker); + pool->shrinker_enabled = false; + } +} + +static int zs_register_shrinker(struct zs_pool *pool) +{ + pool->shrinker.scan_objects = zs_shrinker_scan; + pool->shrinker.count_objects = zs_shrinker_count; + pool->shrinker.batch = 0; + pool->shrinker.seeks = DEFAULT_SEEKS; + + return register_shrinker(&pool->shrinker); +} + /** * zs_create_pool - Creates an allocation pool to work from. * @flags: allocation flags used to allocate pool metadata @@ -1863,6 +1934,12 @@ struct zs_pool *zs_create_pool(char *name, gfp_t flags) if (zs_pool_stat_create(name, pool)) goto err; + /* + * Not critical, we still can use the pool + * and user can trigger compaction manually. + */ + if (zs_register_shrinker(pool) == 0) + pool->shrinker_enabled = true; return pool; err: @@ -1875,6 +1952,7 @@ void zs_destroy_pool(struct zs_pool *pool) { int i; + zs_unregister_shrinker(pool); zs_pool_stat_destroy(pool); for (i = 0; i < zs_size_classes; i++) { |