[RFC v2 66/83] Super: Add file write item cache.

Andiry Xu
2018-03-10T18:28:24Z

nova_file_write_item combines a file write item with a list head.
NOVA uses a linked list of file write items to describe a write operation.

Signed-off-by: Andiry Xu <jix024@cs.ucsd.edu>
---
fs/nova/super.c | 43 ++++++++++++++++++++++++++++++++++++++++++-
fs/nova/super.h | 3 +++
2 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/fs/nova/super.c b/fs/nova/super.c
index 0847e57..9710be8 100644
--- a/fs/nova/super.c
+++ b/fs/nova/super.c
@@ -55,6 +55,7 @@ static const struct export_operations nova_export_ops;

static struct kmem_cache *nova_inode_cachep;
static struct kmem_cache *nova_range_node_cachep;
+static struct kmem_cache *nova_file_write_item_cachep;

/* FIXME: should the following variable be one per NOVA instance? */
@@ -791,6 +792,21 @@ inline void nova_free_inode_node(struct super_block *sb,
nova_free_range_node(node);
}

+inline void nova_free_file_write_item(struct nova_file_write_item *item)
+{
+ kmem_cache_free(nova_file_write_item_cachep, item);
+}
+
+inline struct nova_file_write_item *
+nova_alloc_file_write_item(struct super_block *sb)
+{
+ struct nova_file_write_item *p;
+
+ p = (struct nova_file_write_item *)
+ kmem_cache_alloc(nova_file_write_item_cachep, GFP_NOFS);
+ return p;
+}
+
inline struct nova_range_node *nova_alloc_range_node(struct super_block *sb)
{
struct nova_range_node *p;
@@ -849,6 +865,18 @@ static int __init init_rangenode_cache(void)
return 0;
}

+static int __init init_file_write_item_cache(void)
+{
+ nova_file_write_item_cachep = kmem_cache_create(
+ "nova_file_write_item_cache",
+ sizeof(struct nova_file_write_item),
+ 0, (SLAB_RECLAIM_ACCOUNT |
+ SLAB_MEM_SPREAD), NULL);
+ if (nova_file_write_item_cachep == NULL)
+ return -ENOMEM;
+ return 0;
+}
+
static int __init init_inodecache(void)
{
nova_inode_cachep = kmem_cache_create("nova_inode_cache",
@@ -875,6 +903,11 @@ static void destroy_rangenode_cache(void)
kmem_cache_destroy(nova_range_node_cachep);
}

+static void destroy_file_write_item_cache(void)
+{
+ kmem_cache_destroy(nova_file_write_item_cachep);
+}
+

/*
* the super block writes are all done "on the fly", so the
@@ -974,14 +1007,21 @@ static int __init init_nova_fs(void)
if (rc)
goto out1;

- rc = register_filesystem(&nova_fs_type);
+ rc = init_file_write_item_cache();
if (rc)
goto out2;

+ rc = register_filesystem(&nova_fs_type);
+ if (rc)
+ goto out3;
+
out:
NOVA_END_TIMING(init_t, init_time);
return rc;

+out3:
+ destroy_file_write_item_cache();
+
out2:
destroy_inodecache();

@@ -993,6 +1033,7 @@ static int __init init_nova_fs(void)
static void __exit exit_nova_fs(void)
{
unregister_filesystem(&nova_fs_type);
+ destroy_file_write_item_cache();
destroy_inodecache();
destroy_rangenode_cache();
}
diff --git a/fs/nova/super.h b/fs/nova/super.h
index 56a840e..bcf9548 100644
--- a/fs/nova/super.h
+++ b/fs/nova/super.h
@@ -160,8 +160,11 @@ static inline struct nova_super_block *nova_get_super(struct super_block *sb)
extern void nova_error_mng(struct super_block *sb, const char *fmt, ...);
extern struct nova_range_node *nova_alloc_range_node(struct super_block *sb);
extern inline struct nova_range_node *nova_alloc_inode_node(struct super_block *sb);
+extern struct nova_file_write_item *
+nova_alloc_file_write_item(struct super_block *sb);
extern void nova_free_range_node(struct nova_range_node *node);
extern inline void nova_free_inode_node(struct super_block *sb,
struct nova_range_node *node);
+void nova_free_file_write_item(struct nova_file_write_item *item);

#endif
--
2.7.4