On Tue, Nov 11, 2025 at 09:43:13AM +0000, Suzuki Kuruppassery Poulose wrote:
[...]
if (!is_idle_task(current)) { if (config->ss_ctrl[i] || config->ss_pe_cmp[i]) config->ss_status[i] &= ~TRCSSCSRn_STATUS; }
What happens when we do a system wide session and a CPU is running an idle task ?
For a system wide trace, the ETM device is enabled and disabled by the perf when the session start and finish.
During the session:
- If CPU off states are not enabled, nothing will happen in idle threads, as no CPU PM notifier will be invoked.
- If CPU off states have been enabled, CPU PM notifier will save and restore ETM device context, and keep single-shot status. This is same with current save/restore flow.
I don't see any issue for this.
Thanks, Leo