| Message ID | 20220601122007.1057-2-zhouchengming@bytedance.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] blk-iocost: factor out iocg_deactivate() | expand |
On Wed, Jun 01, 2022 at 08:20:07PM +0800, Chengming Zhou wrote: > We only need to flush wait and indebt stat deltas when the iocg > is in these status. Hey, so, I'm not seeing any actual benefits of the suggested patches and none of them has actual justifications. For the time being, I'm gonna be ignoring these patches. Thanks.
On 2022/6/2 00:23, Tejun Heo wrote: > On Wed, Jun 01, 2022 at 08:20:07PM +0800, Chengming Zhou wrote: >> We only need to flush wait and indebt stat deltas when the iocg >> is in these status. > > Hey, so, I'm not seeing any actual benefits of the suggested patches and > none of them has actual justifications. For the time being, I'm gonna be > ignoring these patches. Hi, the current code will flush wait and indebt stat deltas even for idle iocgs, which seems strange. This patch only do that for iocgs that are in wait or indebt status, so it's a performance and code improvements, although it's minor. Thanks. > > Thanks. >
diff --git a/block/blk-iocost.c b/block/blk-iocost.c index b1f2305e8032..502425b44475 100644 --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -2174,28 +2174,28 @@ static int ioc_check_iocgs(struct ioc *ioc, struct ioc_now *now) spin_lock(&iocg->waitq.lock); - /* flush wait and indebt stat deltas */ - if (iocg->wait_since) { - iocg->stat.wait_us += now->now - iocg->wait_since; - iocg->wait_since = now->now; - } - if (iocg->indebt_since) { - iocg->stat.indebt_us += - now->now - iocg->indebt_since; - iocg->indebt_since = now->now; - } - if (iocg->indelay_since) { - iocg->stat.indelay_us += - now->now - iocg->indelay_since; - iocg->indelay_since = now->now; - } - if (waitqueue_active(&iocg->waitq) || iocg->abs_vdebt || iocg->delay) { /* might be oversleeping vtime / hweight changes, kick */ iocg_kick_waitq(iocg, true, now); if (iocg->abs_vdebt || iocg->delay) nr_debtors++; + + /* flush wait and indebt stat deltas */ + if (iocg->wait_since) { + iocg->stat.wait_us += now->now - iocg->wait_since; + iocg->wait_since = now->now; + } + if (iocg->indebt_since) { + iocg->stat.indebt_us += + now->now - iocg->indebt_since; + iocg->indebt_since = now->now; + } + if (iocg->indelay_since) { + iocg->stat.indelay_us += + now->now - iocg->indelay_since; + iocg->indelay_since = now->now; + } } else if (iocg_is_idle(iocg)) iocg_deactivate(iocg, now);
We only need to flush wait and indebt stat deltas when the iocg is in these status. Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> --- block/blk-iocost.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-)