On Wed 23-02-22 15:41:59, Ritesh Harjani wrote: > On 22/02/23 10:40AM, Jan Kara wrote: > > On Wed 23-02-22 02:04:11, Ritesh Harjani wrote: > > > This adds two more tracepoints for ext4_fc_track_template() & > > > ext4_fc_cleanup() which are helpful in debugging some fast_commit issues. > > > > > > Signed-off-by: Ritesh Harjani <riteshh@xxxxxxxxxxxxx> > > > > So why is this more useful than trace_ext4_fc_track_range() and other > > tracepoints? I don't think it provides any more information? What am I > > missing? > > Thanks Jan for all the reviews. > > So ext4_fc_track_template() adds almost all required information > (including the caller info) in this one trace point along with transaction tid > which is useful for tracking issue similar to what is mentioned in Patch-9. > > (race with if inode is part of two transactions tid where jbd2 full commit > may begin for txn n-1 while inode is still in sbi->s_fc_q[MAIN]) I understand commit tid is interesting but cannot we just add it to tracepoints like trace_ext4_fc_track_range() directly? It would seem useful to have it there and when it is there, the need for ext4_fc_track_template() is not really big. I don't care too much but this tracepoint looked a bit superfluous to me. > And similarly ext4_fc_cleanup() helps with that information about which tid > completed and whether it was called from jbd2 full commit or from fast_commit. Yeah, that one is clear. Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
