f2fs: add an sysfs entry to control the directory level
This patch adds an sysfs entry to control dir_level used by the large directory.
The description of this entry is:
dir_level This parameter controls the directory level to
support large directory. If a directory has a
number of files, it can reduce the file lookup
latency by increasing this dir_level value.
Otherwise, it needs to decrease this value to
reduce the space overhead. The default value is 0.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 475560e..1bd9153 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -184,6 +184,7 @@
F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy);
F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ipu_util, min_ipu_util);
F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_victim_search, max_victim_search);
+F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, dir_level, dir_level);
#define ATTR_LIST(name) (&f2fs_attr_##name.attr)
static struct attribute *f2fs_attrs[] = {
@@ -196,6 +197,7 @@
ATTR_LIST(ipu_policy),
ATTR_LIST(min_ipu_util),
ATTR_LIST(max_victim_search),
+ ATTR_LIST(dir_level),
NULL,
};
@@ -359,6 +361,9 @@
if (test_opt(F2FS_SB(sb), INLINE_XATTR))
set_inode_flag(fi, FI_INLINE_XATTR);
+ /* Will be used by directory only */
+ fi->i_dir_level = F2FS_SB(sb)->dir_level;
+
return &fi->vfs_inode;
}
@@ -785,6 +790,8 @@
for (i = 0; i < NR_COUNT_TYPE; i++)
atomic_set(&sbi->nr_pages[i], 0);
+
+ sbi->dir_level = DEF_DIR_LEVEL;
}
/*