diff options
| author | Tao Ma <boyu.mt@taobao.com> | 2011-01-24 23:23:30 +0800 |
|---|---|---|
| committer | Joel Becker <jlbec@evilplan.org> | 2011-02-20 03:56:12 -0800 |
| commit | 1dd9ffc827b8591aabcf5fea6ea83b69e846deb9 (patch) | |
| tree | 3ac43761aa3e4ed81ac851e376909c407a17e3fe /fs/ocfs2/dir.c | |
| parent | 5bc970e803ad2b1f26771f39376a79dbf0f5bf64 (diff) | |
ocfs2: optimize ocfs2_check_dir_entry() with unlikely() annotations
In cad3f00, ext4_check_dir_entry was modified by adding some unlikely.
Ted described it as "This function gets called a lot for large
directories, and the answer is almost always 'no, no, there's no problem'.
This means using unlikely() is a good thing."
ext3 added the similar change in commit a4ae309.
So change it accordingly in ocfs2.
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: Joel Becker <jlbec@evilplan.org>
Diffstat (limited to 'fs/ocfs2/dir.c')
| -rw-r--r-- | fs/ocfs2/dir.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c index d417b3f9b0c..41b356fefaa 100644 --- a/fs/ocfs2/dir.c +++ b/fs/ocfs2/dir.c @@ -322,21 +322,23 @@ static int ocfs2_check_dir_entry(struct inode * dir, const char *error_msg = NULL; const int rlen = le16_to_cpu(de->rec_len); - if (rlen < OCFS2_DIR_REC_LEN(1)) + if (unlikely(rlen < OCFS2_DIR_REC_LEN(1))) error_msg = "rec_len is smaller than minimal"; - else if (rlen % 4 != 0) + else if (unlikely(rlen % 4 != 0)) error_msg = "rec_len % 4 != 0"; - else if (rlen < OCFS2_DIR_REC_LEN(de->name_len)) + else if (unlikely(rlen < OCFS2_DIR_REC_LEN(de->name_len))) error_msg = "rec_len is too small for name_len"; - else if (((char *) de - bh->b_data) + rlen > dir->i_sb->s_blocksize) + else if (unlikely( + ((char *) de - bh->b_data) + rlen > dir->i_sb->s_blocksize)) error_msg = "directory entry across blocks"; - if (error_msg != NULL) + if (unlikely(error_msg != NULL)) mlog(ML_ERROR, "bad entry in directory #%llu: %s - " "offset=%lu, inode=%llu, rec_len=%d, name_len=%d\n", (unsigned long long)OCFS2_I(dir)->ip_blkno, error_msg, offset, (unsigned long long)le64_to_cpu(de->inode), rlen, de->name_len); + return error_msg == NULL ? 1 : 0; } |