iolog: regrow logs in iolog_delay()
The commit
b85c01f7e9df ("iolog.c: fix inaccurate clat when replay
trace") triggered the assertion failure below for the workload which
does I/O replay as asynchronous I/O together with log recording options
such as write_lat_log.
fio: stat.c:3030: get_cur_log: Assertion `iolog->pending->nr_samples < iolog->pending->max_samples' failed.
fio: pid=40120, got signal=6
The assertion means that too many logs are recorded in the pending log
space which keeps the logs until next log space regrow by reglow_logs()
call. However, reglow_logs() is not called, and the pending log space
runs out.
The trigger commit modified iolog_delay() to call io_u_queued_complete()
so that the asynchronous I/Os can be completed during delays between
replayed I/Os. Before this commit, replayed I/Os were not completed
until all I/O units are consumed. So the free I/O unit list gets empty
periodically, then wait_for_completion() and regrow_logs() were called
periodically. After this commit, all I/O units are not consumed, so
wait_for_completion() and regrow_logs() are no longer called for long
duration. Hence the assertion failure.
To avoid the assertion, add the check for log regrow and reglow_logs()
call in iolog_delay().
Fixes:
b85c01f7e9df ("iolog.c: fix inaccurate clat when replay trace")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Link: https://lore.kernel.org/r/20240321031011.4140040-2-shinichiro.kawasaki@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>