On 2013/11/07 8:45 PM, "Theodore Ts'o" <tytso@xxxxxxx> wrote: >On Wed, Nov 06, 2013 at 03:42:32AM -0700, Andreas Dilger wrote: >> @@ -4542,9 +4551,9 @@ int ext4_getattr(struct vfsmount *mnt, struct >>dentry *dentry, >> * blocks for this file. >> */ >> delalloc_blocks = EXT4_C2B(EXT4_SB(inode->i_sb), >> - EXT4_I(inode)->i_reserved_data_blocks); >> + EXT4_I(inode)->i_reserved_data_blocks); >> + stat->blocks += delalloc_blocks << (inode->i_sb->s_blocksize_bits - >>9); >> >> - stat->blocks += (delalloc_blocks << inode->i_sb->s_blocksize_bits)>>9; > >Why this change to the calculation to stat->blocks? Just code cleanup. The lack of spaces around ">>9" irked me. The calculation is the same (s_blocksize_bits can never be less than 10 for ext* filesystems), but avoids doing two separate shifts that the compiler cannot optimize together due to parenthesis and potential side effects (e.g. this kind of operation could be used to mask off the top bits, but isn't doing so here). Cheers, Andreas -- Andreas Dilger Lustre Software Architect Intel High Performance Data Division -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
