[PATCH 1/3] f2fs: make module init/exit match their sequence

Youling Tang
2024-07-11T07:49:39Z

From: Youling Tang <tangyouling@kylinos.cn>

Use init_sequence to ensure that modules init and exit are in sequence
and to simplify the code.

Signed-off-by: Youling Tang <tangyouling@kylinos.cn>
---
fs/f2fs/debug.c | 3 +-
fs/f2fs/f2fs.h | 4 +-
fs/f2fs/super.c | 210 ++++++++++++++++++++++++------------------------
3 files changed, 107 insertions(+), 110 deletions(-)

diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
index 8b0e1e71b667..c08ecf807066 100644
--- a/fs/f2fs/debug.c
+++ b/fs/f2fs/debug.c
@@ -727,7 +727,7 @@ void f2fs_destroy_stats(struct f2fs_sb_info *sbi)
kfree(si);
}

-void __init f2fs_create_root_stats(void)
+int __init f2fs_create_root_stats(void)
{
#ifdef CONFIG_DEBUG_FS
f2fs_debugfs_root = debugfs_create_dir("f2fs", NULL);
@@ -735,6 +735,7 @@ void __init f2fs_create_root_stats(void)
debugfs_create_file("status", 0444, f2fs_debugfs_root, NULL,
&stat_fops);
#endif
+ return 0;
}

void f2fs_destroy_root_stats(void)
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 1974b6aff397..d546bd301565 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -4086,7 +4086,7 @@ static inline struct f2fs_stat_info *F2FS_STAT(struct f2fs_sb_info *sbi)

int f2fs_build_stats(struct f2fs_sb_info *sbi);
void f2fs_destroy_stats(struct f2fs_sb_info *sbi);
-void __init f2fs_create_root_stats(void);
+int __init f2fs_create_root_stats(void);
void f2fs_destroy_root_stats(void);
void f2fs_update_sit_info(struct f2fs_sb_info *sbi);
#else
@@ -4128,7 +4128,7 @@ void f2fs_update_sit_info(struct f2fs_sb_info *sbi);

static inline int f2fs_build_stats(struct f2fs_sb_info *sbi) { return 0; }
static inline void f2fs_destroy_stats(struct f2fs_sb_info *sbi) { }
-static inline void __init f2fs_create_root_stats(void) { }
+static inline int __init f2fs_create_root_stats(void) { }
static inline void f2fs_destroy_root_stats(void) { }
static inline void f2fs_update_sit_info(struct f2fs_sb_info *sbi) {}
#endif
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 1f1b3647a998..19509942b837 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -4940,120 +4940,116 @@ static void destroy_inodecache(void)
kmem_cache_destroy(f2fs_inode_cachep);
}

-static int __init init_f2fs_fs(void)
+static int register_f2fs(void)
{
- int err;
+ return register_filesystem(&f2fs_fs_type);
+}

- err = init_inodecache();
- if (err)
- goto fail;
- err = f2fs_create_node_manager_caches();
- if (err)
- goto free_inodecache;
- err = f2fs_create_segment_manager_caches();
- if (err)
- goto free_node_manager_caches;
- err = f2fs_create_checkpoint_caches();
- if (err)
- goto free_segment_manager_caches;
- err = f2fs_create_recovery_cache();
- if (err)
- goto free_checkpoint_caches;
- err = f2fs_create_extent_cache();
- if (err)
- goto free_recovery_cache;
- err = f2fs_create_garbage_collection_cache();
- if (err)
- goto free_extent_cache;
- err = f2fs_init_sysfs();
- if (err)
- goto free_garbage_collection_cache;
- err = f2fs_init_shrinker();
- if (err)
- goto free_sysfs;
- err = register_filesystem(&f2fs_fs_type);
- if (err)
- goto free_shrinker;
- f2fs_create_root_stats();
- err = f2fs_init_post_read_processing();
- if (err)
- goto free_root_stats;
- err = f2fs_init_iostat_processing();
- if (err)
- goto free_post_read;
- err = f2fs_init_bio_entry_cache();
- if (err)
- goto free_iostat;
- err = f2fs_init_bioset();
- if (err)
- goto free_bio_entry_cache;
- err = f2fs_init_compress_mempool();
- if (err)
- goto free_bioset;
- err = f2fs_init_compress_cache();
- if (err)
- goto free_compress_mempool;
- err = f2fs_create_casefold_cache();
- if (err)
- goto free_compress_cache;
- return 0;
-free_compress_cache:
- f2fs_destroy_compress_cache();
-free_compress_mempool:
- f2fs_destroy_compress_mempool();
-free_bioset:
- f2fs_destroy_bioset();
-free_bio_entry_cache:
- f2fs_destroy_bio_entry_cache();
-free_iostat:
- f2fs_destroy_iostat_processing();
-free_post_read:
- f2fs_destroy_post_read_processing();
-free_root_stats:
- f2fs_destroy_root_stats();
+static void unregister_f2fs(void)
+{
unregister_filesystem(&f2fs_fs_type);
-free_shrinker:
- f2fs_exit_shrinker();
-free_sysfs:
- f2fs_exit_sysfs();
-free_garbage_collection_cache:
- f2fs_destroy_garbage_collection_cache();
-free_extent_cache:
- f2fs_destroy_extent_cache();
-free_recovery_cache:
- f2fs_destroy_recovery_cache();
-free_checkpoint_caches:
- f2fs_destroy_checkpoint_caches();
-free_segment_manager_caches:
- f2fs_destroy_segment_manager_caches();
-free_node_manager_caches:
- f2fs_destroy_node_manager_caches();
-free_inodecache:
- destroy_inodecache();
-fail:
- return err;
+}
+
+/* Helper structure for long init/exit functions. */
+struct init_sequence {
+ int (*init_func)(void);
+ /* Can be NULL if the init_func doesn't need cleanup. */
+ void (*exit_func)(void);
+};
+
+static const struct init_sequence mod_init_seq[] = {
+ {
+ .init_func = init_inodecache,
+ .exit_func = destroy_inodecache,
+ }, {
+ .init_func = f2fs_create_node_manager_caches,
+ .exit_func = f2fs_destroy_node_manager_caches,
+ }, {
+ .init_func = f2fs_create_segment_manager_caches,
+ .exit_func = f2fs_destroy_segment_manager_caches,
+ }, {
+ .init_func = f2fs_create_checkpoint_caches,
+ .exit_func = f2fs_destroy_checkpoint_caches,
+ }, {
+ .init_func = f2fs_create_recovery_cache,
+ .exit_func = f2fs_destroy_recovery_cache,
+ }, {
+ .init_func = f2fs_create_extent_cache,
+ .exit_func = f2fs_destroy_extent_cache,
+ }, {
+ .init_func = f2fs_create_garbage_collection_cache,
+ .exit_func = f2fs_destroy_garbage_collection_cache,
+ }, {
+ .init_func = f2fs_init_sysfs,
+ .exit_func = f2fs_exit_sysfs,
+ }, {
+ .init_func = f2fs_init_shrinker,
+ .exit_func = f2fs_exit_shrinker,
+ }, {
+ .init_func = register_f2fs,
+ .exit_func = unregister_f2fs,
+ }, {
+ .init_func = f2fs_create_root_stats,
+ .exit_func = f2fs_destroy_root_stats,
+ }, {
+ .init_func = f2fs_init_post_read_processing,
+ .exit_func = f2fs_destroy_post_read_processing,
+ }, {
+ .init_func = f2fs_init_iostat_processing,
+ .exit_func = f2fs_destroy_iostat_processing,
+ }, {
+ .init_func = f2fs_init_bio_entry_cache,
+ .exit_func = f2fs_destroy_bio_entry_cache,
+ }, {
+ .init_func = f2fs_init_bioset,
+ .exit_func = f2fs_destroy_bioset,
+ }, {
+ .init_func = f2fs_init_compress_mempool,
+ .exit_func = f2fs_destroy_compress_mempool,
+ }, {
+ .init_func = f2fs_init_compress_cache,
+ .exit_func = f2fs_destroy_compress_cache,
+ }, {
+ .init_func = f2fs_create_casefold_cache,
+ .exit_func = f2fs_destroy_casefold_cache,
+ }
+};
+
+static bool mod_init_result[ARRAY_SIZE(mod_init_seq)];
+
+static __always_inline void f2fs_exit_f2fs_fs(void)
+{
+ int i;
+
+ for (i = ARRAY_SIZE(mod_init_seq) - 1; i >= 0; i--) {
+ if (!mod_init_result[i])
+ continue;
+ if (mod_init_seq[i].exit_func)
+ mod_init_seq[i].exit_func();
+ mod_init_result[i] = false;
+ }
}

static void __exit exit_f2fs_fs(void)
{
- f2fs_destroy_casefold_cache();
- f2fs_destroy_compress_cache();
- f2fs_destroy_compress_mempool();
- f2fs_destroy_bioset();
- f2fs_destroy_bio_entry_cache();
- f2fs_destroy_iostat_processing();
- f2fs_destroy_post_read_processing();
- f2fs_destroy_root_stats();
- unregister_filesystem(&f2fs_fs_type);
- f2fs_exit_shrinker();
- f2fs_exit_sysfs();
- f2fs_destroy_garbage_collection_cache();
- f2fs_destroy_extent_cache();
- f2fs_destroy_recovery_cache();
- f2fs_destroy_checkpoint_caches();
- f2fs_destroy_segment_manager_caches();
- f2fs_destroy_node_manager_caches();
- destroy_inodecache();
+ f2fs_exit_f2fs_fs();
+}
+
+static int __init init_f2fs_fs(void)
+{
+ int ret;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(mod_init_seq); i++) {
+ BUG_ON(mod_init_result[i]);
+ ret = mod_init_seq[i].init_func();
+ if (ret < 0) {
+ f2fs_exit_f2fs_fs();
+ return ret;
+ }
+ mod_init_result[i] = true;
+ }
+ return 0;
}

module_init(init_f2fs_fs)
--
2.34.1