diff options
| author | Kemeng Shi <shikemeng@huawei.com> | 2022-10-18 20:19:30 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-12-01 07:44:12 -0700 |
| commit | 63c9eac4b6d75859703f5820414986edefb01210 (patch) | |
| tree | e4db3eb364bf6f664f99547825707b5cf5b7513b /include | |
| parent | c6d2efdd38b4e45741e103b6338f08e5ff2aae03 (diff) | |
blk-iocost: Trace vtime_base_rate instead of vtime_rate
Since commit ac33e91e2daca ("blk-iocost: implement vtime loss
compensation") rename original vtime_rate to vtime_base_rate
and current vtime_rate is original vtime_rate with compensation.
The current rate showed in tracepoint is mixed with vtime_rate
and vtime_base_rate:
1) In function ioc_adjust_base_vrate, the first trace_iocost_ioc_vrate_adj
shows vtime_rate, the second trace_iocost_ioc_vrate_adj shows
vtime_base_rate.
2) In function iocg_activate shows vtime_rate by calling
TRACE_IOCG_PATH(iocg_activate...
3) In function ioc_check_iocgs shows vtime_rate by calling
TRACE_IOCG_PATH(iocg_idle...
Trace vtime_base_rate instead of vtime_rate as:
1) Before commit ac33e91e2daca ("blk-iocost: implement vtime loss
compensation"), the traced rate is without compensation, so still
show rate without compensation.
2) The vtime_base_rate is more stable while vtime_rate heavily depends on
excess budeget on current period which may change abruptly in next period.
Signed-off-by: Kemeng Shi <shikemeng@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20221018121932.10792-4-shikemeng@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'include')
| -rw-r--r-- | include/trace/events/iocost.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/trace/events/iocost.h b/include/trace/events/iocost.h index 6d1626e7a4ce..af8bfed528fc 100644 --- a/include/trace/events/iocost.h +++ b/include/trace/events/iocost.h @@ -38,7 +38,7 @@ DECLARE_EVENT_CLASS(iocost_iocg_state, __assign_str(cgroup, path); __entry->now = now->now; __entry->vnow = now->vnow; - __entry->vrate = now->vrate; + __entry->vrate = iocg->ioc->vtime_base_rate; __entry->last_period = last_period; __entry->cur_period = cur_period; __entry->vtime = vtime; @@ -160,7 +160,7 @@ TRACE_EVENT(iocost_ioc_vrate_adj, TP_fast_assign( __assign_str(devname, ioc_name(ioc)); - __entry->old_vrate = atomic64_read(&ioc->vtime_rate); + __entry->old_vrate = ioc->vtime_base_rate; __entry->new_vrate = new_vrate; __entry->busy_level = ioc->busy_level; __entry->read_missed_ppm = missed_ppm[READ]; |