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| author | Tejun Heo <tj@kernel.org> | 2019-09-26 02:02:07 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2019-09-26 10:11:58 +0300 |
| commit | 25d41e4aadb0788b4fae8a8fca90f437b9ebd727 (patch) | |
| tree | c6bf9df51f0bb42339a3c2c929b990b2c485fc48 /block/blk-iocost.c | |
| parent | b89f625e28d44552083f43752f62d8621ded0a04 (diff) | |
| download | linux-25d41e4aadb0788b4fae8a8fca90f437b9ebd727.tar.xz | |
iocost: better trace vrate changes
vrate_adj tracepoint traces vrate changes; however, it does so only
when busy_level is non-zero. busy_level turning to zero can sometimes
be as interesting an event. This patch also enables vrate_adj
tracepoint on other vrate related events - busy_level changes and
non-zero nr_lagging.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-iocost.c')
| -rw-r--r-- | block/blk-iocost.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/block/blk-iocost.c b/block/blk-iocost.c index 3b39deb8b9f8..32d4d6d86a99 100644 --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -1343,7 +1343,7 @@ static void ioc_timer_fn(struct timer_list *timer) u32 ppm_wthr = MILLION - ioc->params.qos[QOS_WPPM]; u32 missed_ppm[2], rq_wait_pct; u64 period_vtime; - int i; + int prev_busy_level, i; /* how were the latencies during the period? */ ioc_lat_stat(ioc, missed_ppm, &rq_wait_pct); @@ -1531,6 +1531,7 @@ skip_surplus_transfers: * and experiencing shortages but not surpluses, we're too stingy * and should increase vtime rate. */ + prev_busy_level = ioc->busy_level; if (rq_wait_pct > RQ_WAIT_BUSY_PCT || missed_ppm[READ] > ppm_rthr || missed_ppm[WRITE] > ppm_wthr) { @@ -1592,6 +1593,10 @@ skip_surplus_transfers: atomic64_set(&ioc->vtime_rate, vrate); ioc->inuse_margin_vtime = DIV64_U64_ROUND_UP( ioc->period_us * vrate * INUSE_MARGIN_PCT, 100); + } else if (ioc->busy_level != prev_busy_level || nr_lagging) { + trace_iocost_ioc_vrate_adj(ioc, atomic64_read(&ioc->vtime_rate), + &missed_ppm, rq_wait_pct, nr_lagging, + nr_shortages, nr_surpluses); } ioc_refresh_params(ioc, false); |