f2fs: introduce f2fs_balance_fs_bg for some background jobs

This patch merges some background jobs into this new function.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

4 files changed, 15 insertions, 10 deletions

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 6dff777cd94a..a61cc5f84638 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -965,6 +965,7 @@ long f2fs_compat_ioctl(struct file *, unsigned int, unsigned long);
  */
 void f2fs_set_inode_flags(struct inode *);
 struct inode *f2fs_iget(struct super_block *, unsigned long);
+int try_to_free_nats(struct f2fs_sb_info *, int);
 void update_inode(struct inode *, struct page *);
 int update_inode_page(struct inode *);
 int f2fs_write_inode(struct inode *, struct writeback_control *);
@@ -1045,6 +1046,7 @@ void destroy_node_manager_caches(void);
  * segment.c
  */
 void f2fs_balance_fs(struct f2fs_sb_info *);
+void f2fs_balance_fs_bg(struct f2fs_sb_info *);
 void invalidate_blocks(struct f2fs_sb_info *, block_t);
 void clear_prefree_segments(struct f2fs_sb_info *);
 int npages_for_summary_flush(struct f2fs_sb_info *);
diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index 783c6cc6253c..b7ad1ec7e4cc 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -83,9 +83,8 @@ static int gc_thread_func(void *data)
                 if (f2fs_gc(sbi))
                         wait_ms = gc_th->no_gc_sleep_time;
 
-                /* balancing prefree segments */
-                if (excess_prefree_segs(sbi))
-                        f2fs_sync_fs(sbi->sb, true);
+                /* balancing f2fs's metadata periodically */
+                f2fs_balance_fs_bg(sbi);
 
         } while (!kthread_should_stop());
         return 0;
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 89dd8a5a3ca3..7bac4815f1d6 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -240,7 +240,7 @@ retry:
         write_unlock(&nm_i->nat_tree_lock);
 }
 
-static int try_to_free_nats(struct f2fs_sb_info *sbi, int nr_shrink)
+int try_to_free_nats(struct f2fs_sb_info *sbi, int nr_shrink)
 {
         struct f2fs_nm_info *nm_i = NM_I(sbi);
 
@@ -1205,12 +1205,8 @@ static int f2fs_write_node_pages(struct address_space *mapping,
         struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);
         long nr_to_write = wbc->nr_to_write;
 
-        /* First check balancing cached NAT entries */
-        if (try_to_free_nats(sbi, NAT_ENTRY_PER_BLOCK) ||
-                                excess_prefree_segs(sbi)) {
-                f2fs_sync_fs(sbi->sb, true);
-                return 0;
-        }
+        /* balancing f2fs's metadata in background */
+        f2fs_balance_fs_bg(sbi);
 
         /* collect a number of dirty node pages and write together */
         if (get_pages(sbi, F2FS_DIRTY_NODES) < COLLECT_DIRTY_NODES)
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 62b52f2f293a..8e5ca2869913 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -36,6 +36,14 @@ void f2fs_balance_fs(struct f2fs_sb_info *sbi)
         }
 }
 
+void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi)
+{
+        /* check the # of cached NAT entries and prefree segments */
+        if (try_to_free_nats(sbi, NAT_ENTRY_PER_BLOCK) ||
+                                excess_prefree_segs(sbi))
+                f2fs_sync_fs(sbi->sb, true);
+}
+
 static void __locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
                 enum dirty_type dirty_type)
 {