f2fs: introduce sysfs readdir_ra to readahead inode block in readdir
This patch introduces a sysfs interface readdir_ra to enable/disable
readaheading inode block in f2fs_readdir. When readdir_ra is enabled,
it improves the performance of "readdir + stat".
For 300,000 files:
time find /data/test > /dev/null
disable readdir_ra: 1m25.69s real 0m01.94s user 0m50.80s system
enable readdir_ra: 0m18.55s real 0m00.44s user 0m15.39s system
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index 2d98d87..724304d 100644
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -798,6 +798,7 @@ int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d,
unsigned int bit_pos;
struct f2fs_dir_entry *de = NULL;
struct fscrypt_str de_name = FSTR_INIT(NULL, 0);
+ struct f2fs_sb_info *sbi = F2FS_I_SB(d->inode);
bit_pos = ((unsigned long)ctx->pos % d->max);
@@ -836,6 +837,9 @@ int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d,
le32_to_cpu(de->ino), d_type))
return 1;
+ if (sbi->readdir_ra == 1)
+ ra_node_page(sbi, le32_to_cpu(de->ino));
+
bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
ctx->pos = start_pos + bit_pos;
}