From: Shaoying Xu shaoyi@amazon.com
commit 39fec6889d15a658c3a3ebb06fd69d3584ddffd3 upstream.
Ext4 file system has default lazy inode table initialization setup once it is mounted. However, it has issue on computing the next schedule time that makes the timeout same amount in jiffies but different real time in secs if with various HZ values. Therefore, fix by measuring the current time in a more granular unit nanoseconds and make the next schedule time independent of the HZ value.
Fixes: bfff68738f1c ("ext4: add support for lazy inode table initialization") Signed-off-by: Shaoying Xu shaoyi@amazon.com Cc: stable@vger.kernel.org Signed-off-by: Theodore Ts'o tytso@mit.edu Link: https://lore.kernel.org/r/20210902164412.9994-2-shaoyi@amazon.com Signed-off-by: Theodore Ts'o tytso@mit.edu Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/ext4/super.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)
--- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3427,9 +3427,9 @@ static int ext4_run_li_request(struct ex struct super_block *sb = elr->lr_super; ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count; ext4_group_t group = elr->lr_next_group; - unsigned long timeout = 0; unsigned int prefetch_ios = 0; int ret = 0; + u64 start_time;
if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) { elr->lr_next_group = ext4_mb_prefetch(sb, group, @@ -3466,14 +3466,13 @@ static int ext4_run_li_request(struct ex ret = 1;
if (!ret) { - timeout = jiffies; + start_time = ktime_get_real_ns(); ret = ext4_init_inode_table(sb, group, elr->lr_timeout ? 0 : 1); trace_ext4_lazy_itable_init(sb, group); if (elr->lr_timeout == 0) { - timeout = (jiffies - timeout) * - EXT4_SB(elr->lr_super)->s_li_wait_mult; - elr->lr_timeout = timeout; + elr->lr_timeout = nsecs_to_jiffies((ktime_get_real_ns() - start_time) * + EXT4_SB(elr->lr_super)->s_li_wait_mult); } elr->lr_next_sched = jiffies + elr->lr_timeout; elr->lr_next_group = group + 1;