Hello, Tejun. 在 2026/9/22 03:37, Tejun Heo 写道: > Hello, Tao. > > On Fri, 18 Sep 2026 13:49:59 +0800, Tao Cui wrote: > >> + /* >> + * vrate and period_us change right below; snapshot the values >> + * this period ran in so the tick below reports the period's own >> + * parameters instead of the next period's. >> + */ >> + tick_period_us = ioc->period_us; >> + tick_vrate = ioc->vtime_base_rate; > > Everything the tick reports is already final at this point. busy_level > was just computed, running and cur_period haven't changed yet, and > nr_active and usage_us_sum are complete. Can you emit the tracepoint here > instead and drop the snapshots? The event can then read the fields > directly and the only cost outside the static key is the nr_active > increment. >
That's a cleaner placement. The tracepoint is now emitted before the period refresh, after busy_level is clamped, and the temporary tick_* snapshots are removed; the event reads the ioc fields directly. nr_active remains the only cost outside the static key. Thanks, Tao > Looks fine otherwise. > > Thanks. > > -- > tejun
