From 63c9eac4b6d75859703f5820414986edefb01210 Mon Sep 17 00:00:00 2001 From: Kemeng Shi Date: Tue, 18 Oct 2022 20:19:30 +0800 Subject: 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 Acked-by: Tejun Heo Link: https://lore.kernel.org/r/20221018121932.10792-4-shikemeng@huawei.com Signed-off-by: Jens Axboe --- include/trace/events/iocost.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include') 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]; -- cgit v1.2.3-58-ga151