The s_flex_groups array should have been initialized using atomic_add to sum up the free counts from the block groups that make up a flex_bg. By using atomic_set, the value of the s_flex_groups array was set to the values of the last block group in the flex_bg. The impact of this bug is that the block and inode allocation algorithms might not pick the best flex_bg for new allocation. Thanks to Damien Guibouret for pointing out this problem! Signed-off-by: "Theodore Ts'o" <tytso@xxxxxxx> --- fs/ext4/super.c | 12 ++++++------ 1 files changed, 6 insertions(+), 6 deletions(-) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 9f6fa3f..04c6933 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1694,12 +1694,12 @@ static int ext4_fill_flex_info(struct super_block *sb) gdp = ext4_get_group_desc(sb, i, NULL); flex_group = ext4_flex_group(sbi, i); - atomic_set(&sbi->s_flex_groups[flex_group].free_inodes, - ext4_free_inodes_count(sb, gdp)); - atomic_set(&sbi->s_flex_groups[flex_group].free_blocks, - ext4_free_blks_count(sb, gdp)); - atomic_set(&sbi->s_flex_groups[flex_group].used_dirs, - ext4_used_dirs_count(sb, gdp)); + atomic_add(ext4_free_inodes_count(sb, gdp), + &sbi->s_flex_groups[flex_group].free_inodes); + atomic_add(ext4_free_blks_count(sb, gdp), + &sbi->s_flex_groups[flex_group].free_blocks); + atomic_add(ext4_used_dirs_count(sb, gdp), + &sbi->s_flex_groups[flex_group].used_dirs); } return 1; -- 1.6.3.2.1.gb9f7d.dirty -- 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
