diff --git a/mm/Kconfig b/mm/Kconfig
index 4395b12869c832dba4a62747658f2238dd1257f7..de5239c152f9fb8ea9f66361fa7fba7cdc1d00d9 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -602,6 +602,16 @@ config PGTABLE_MAPPING
You can check speed with zsmalloc benchmark:
https://github.com/spartacus06/zsmapbench
+config ZSMALLOC_STAT
+ bool "Export zsmalloc statistics"
+ depends on ZSMALLOC
+ select DEBUG_FS
+ help
+ This option enables code in the zsmalloc to collect various
+ statistics about whats happening in zsmalloc and exports that
+ information to userspace via debugfs.
+ If unsure, say N.
+
config GENERIC_EARLY_IOREMAP
bool
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index 2359e61b02bf46e94785eef14aa641a015f38192..0dec1fa5f6565dab6be9c9515d52c9caae8e0ea6 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -91,6 +91,7 @@
#include <linux/hardirq.h>
#include <linux/spinlock.h>
#include <linux/types.h>
+#include <linux/debugfs.h>
#include <linux/zsmalloc.h>
#include <linux/zpool.h>
@@ -168,6 +169,22 @@ enum fullness_group {
ZS_FULL
};
+enum zs_stat_type {
+ OBJ_ALLOCATED,
+ OBJ_USED,
+ NR_ZS_STAT_TYPE,
+};
+
+#ifdef CONFIG_ZSMALLOC_STAT
+
+static struct dentry *zs_stat_root;
+
+struct zs_size_stat {
+ unsigned long objs[NR_ZS_STAT_TYPE];
+};
+
+#endif
+
/*
* number of size_classes
*/
@@ -200,6 +217,10 @@ struct size_class {
/* Number of PAGE_SIZE sized pages to combine to form a 'zspage' */
int pages_per_zspage;
+#ifdef CONFIG_ZSMALLOC_STAT
+ struct zs_size_stat stats;
+#endif
+
spinlock_t lock;
struct page *fullness_list[_ZS_NR_FULLNESS_GROUPS];
@@ -217,10 +238,16 @@ struct link_free {
};
struct zs_pool {
+ char *name;
+
struct size_class **size_class;
gfp_t flags; /* allocation flags used when growing pool */
atomic_long_t pages_allocated;
+
+#ifdef CONFIG_ZSMALLOC_STAT
+ struct dentry *stat_dentry;
+#endif
};
/*
@@ -942,6 +969,166 @@ static bool can_merge(struct size_class *prev, int size, int pages_per_zspage)
return true;
}
+#ifdef CONFIG_ZSMALLOC_STAT
+
+static inline void zs_stat_inc(struct size_class *class,
+ enum zs_stat_type type, unsigned long cnt)
+{
+ class->stats.objs[type] += cnt;
+}
+
+static inline void zs_stat_dec(struct size_class *class,
+ enum zs_stat_type type, unsigned long cnt)
+{
+ class->stats.objs[type] -= cnt;
+}
+
+static inline unsigned long zs_stat_get(struct size_class *class,
+ enum zs_stat_type type)
+{
+ return class->stats.objs[type];
+}
+
+static int __init zs_stat_init(void)
+{
+ if (!debugfs_initialized())
+ return -ENODEV;
+
+ zs_stat_root = debugfs_create_dir("zsmalloc", NULL);
+ if (!zs_stat_root)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void __exit zs_stat_exit(void)
+{
+ debugfs_remove_recursive(zs_stat_root);
+}
+
+static int zs_stats_size_show(struct seq_file *s, void *v)
+{
+ int i;
+ struct zs_pool *pool = s->private;
+ struct size_class *class;
+ int objs_per_zspage;
+ unsigned long obj_allocated, obj_used, pages_used;
+ unsigned long total_objs = 0, total_used_objs = 0, total_pages = 0;
+
+ seq_printf(s, " %5s %5s %13s %10s %10s\n", "class", "size",
+ "obj_allocated", "obj_used", "pages_used");
+
+ for (i = 0; i < zs_size_classes; i++) {
+ class = pool->size_class[i];
+
+ if (class->index != i)
+ continue;
+
+ spin_lock(&class->lock);
+ obj_allocated = zs_stat_get(class, OBJ_ALLOCATED);
+ obj_used = zs_stat_get(class, OBJ_USED);
+ spin_unlock(&class->lock);
+
+ objs_per_zspage = get_maxobj_per_zspage(class->size,
+ class->pages_per_zspage);
+ pages_used = obj_allocated / objs_per_zspage *
+ class->pages_per_zspage;
+
+ seq_printf(s, " %5u %5u %10lu %10lu %10lu\n", i,
+ class->size, obj_allocated, obj_used, pages_used);
+
+ total_objs += obj_allocated;
+ total_used_objs += obj_used;
+ total_pages += pages_used;
+ }
+
+ seq_puts(s, "\n");
+ seq_printf(s, " %5s %5s %10lu %10lu %10lu\n", "Total", "",
+ total_objs, total_used_objs, total_pages);
+
+ return 0;
+}
+
+static int zs_stats_size_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, zs_stats_size_show, inode->i_private);
+}
+
+static const struct file_operations zs_stat_size_ops = {
+ .open = zs_stats_size_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int zs_pool_stat_create(char *name, struct zs_pool *pool)
+{
+ struct dentry *entry;
+
+ if (!zs_stat_root)
+ return -ENODEV;
+
+ entry = debugfs_create_dir(name, zs_stat_root);
+ if (!entry) {
+ pr_warn("debugfs dir <%s> creation failed\n", name);
+ return -ENOMEM;
+ }
+ pool->stat_dentry = entry;
+
+ entry = debugfs_create_file("obj_in_classes", S_IFREG | S_IRUGO,
+ pool->stat_dentry, pool, &zs_stat_size_ops);
+ if (!entry) {
+ pr_warn("%s: debugfs file entry <%s> creation failed\n",
+ name, "obj_in_classes");
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static void zs_pool_stat_destroy(struct zs_pool *pool)
+{
+ debugfs_remove_recursive(pool->stat_dentry);
+}
+
+#else /* CONFIG_ZSMALLOC_STAT */
+
+static inline void zs_stat_inc(struct size_class *class,
+ enum zs_stat_type type, unsigned long cnt)
+{
+}
+
+static inline void zs_stat_dec(struct size_class *class,
+ enum zs_stat_type type, unsigned long cnt)
+{
+}
+
+static inline unsigned long zs_stat_get(struct size_class *class,
+ enum zs_stat_type type)
+{
+ return 0;
+}
+
+static int __init zs_stat_init(void)
+{
+ return 0;
+}
+
+static void __exit zs_stat_exit(void)
+{
+}
+
+static inline int zs_pool_stat_create(char *name, struct zs_pool *pool)
+{
+ return 0;
+}
+
+static inline void zs_pool_stat_destroy(struct zs_pool *pool)
+{
+}
+
+#endif
+
unsigned long zs_get_total_pages(struct zs_pool *pool)
{
return atomic_long_read(&pool->pages_allocated);
@@ -1074,7 +1261,10 @@ unsigned long zs_malloc(struct zs_pool *pool, size_t size)
set_zspage_mapping(first_page, class->index, ZS_EMPTY);
atomic_long_add(class->pages_per_zspage,
&pool->pages_allocated);
+
spin_lock(&class->lock);
+ zs_stat_inc(class, OBJ_ALLOCATED, get_maxobj_per_zspage(
+ class->size, class->pages_per_zspage));
}
obj = (unsigned long)first_page->freelist;
@@ -1088,6 +1278,7 @@ unsigned long zs_malloc(struct zs_pool *pool, size_t size)
kunmap_atomic(vaddr);
first_page->inuse++;
+ zs_stat_inc(class, OBJ_USED, 1);
/* Now move the zspage to another fullness group, if required */
fix_fullness_group(pool, first_page);
spin_unlock(&class->lock);
@@ -1128,6 +1319,12 @@ void zs_free(struct zs_pool *pool, unsigned long obj)
first_page->inuse--;
fullness = fix_fullness_group(pool, first_page);
+
+ zs_stat_dec(class, OBJ_USED, 1);
+ if (fullness == ZS_EMPTY)
+ zs_stat_dec(class, OBJ_ALLOCATED, get_maxobj_per_zspage(
+ class->size, class->pages_per_zspage));
+
spin_unlock(&class->lock);
if (fullness == ZS_EMPTY) {
@@ -1158,9 +1355,16 @@ struct zs_pool *zs_create_pool(char *name, gfp_t flags)
if (!pool)
return NULL;
+ pool->name = kstrdup(name, GFP_KERNEL);
+ if (!pool->name) {
+ kfree(pool);
+ return NULL;
+ }
+
pool->size_class = kcalloc(zs_size_classes, sizeof(struct size_class *),
GFP_KERNEL);
if (!pool->size_class) {
+ kfree(pool->name);
kfree(pool);
return NULL;
}
@@ -1210,6 +1414,9 @@ struct zs_pool *zs_create_pool(char *name, gfp_t flags)
pool->flags = flags;
+ if (zs_pool_stat_create(name, pool))
+ goto err;
+
return pool;
err:
@@ -1222,6 +1429,8 @@ void zs_destroy_pool(struct zs_pool *pool)
{
int i;
+ zs_pool_stat_destroy(pool);
+
for (i = 0; i < zs_size_classes; i++) {
int fg;
struct size_class *class = pool->size_class[i];
@@ -1242,6 +1451,7 @@ void zs_destroy_pool(struct zs_pool *pool)
}
kfree(pool->size_class);
+ kfree(pool->name);
kfree(pool);
}
EXPORT_SYMBOL_GPL(zs_destroy_pool);
@@ -1250,17 +1460,30 @@ static int __init zs_init(void)
{
int ret = zs_register_cpu_notifier();
- if (ret) {
- zs_unregister_cpu_notifier();
- return ret;
- }
+ if (ret)
+ goto notifier_fail;
init_zs_size_classes();
#ifdef CONFIG_ZPOOL
zpool_register_driver(&zs_zpool_driver);
#endif
+
+ ret = zs_stat_init();
+ if (ret) {
+ pr_err("zs stat initialization failed\n");
+ goto stat_fail;
+ }
return 0;
+
+stat_fail:
+#ifdef CONFIG_ZPOOL
+ zpool_unregister_driver(&zs_zpool_driver);
+#endif
+notifier_fail:
+ zs_unregister_cpu_notifier();
+
+ return ret;
}
static void __exit zs_exit(void)
@@ -1269,6 +1492,8 @@ static void __exit zs_exit(void)
zpool_unregister_driver(&zs_zpool_driver);
#endif
zs_unregister_cpu_notifier();
+
+ zs_stat_exit();
}
module_init(zs_init);