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rtla/timerlat_bpf: Stop tracing on user latency

rtla-timerlat allows a *thread* latency threshold to be set via the
-T/--thread option. However, the timerlat tracer calls this *total*
latency (stop_tracing_total_us), and stops tracing also when the
return-to-user latency is over the threshold.

Change the behavior of the timerlat BPF program to reflect what the
timerlat tracer is doing, to avoid discrepancy between stopping
collecting data in the BPF program and stopping tracing in the timerlat
tracer.

Cc: stable@vger.kernel.org
Fixes: e34293ddcebd ("rtla/timerlat: Add BPF skeleton to collect samples")
Reviewed-by: Wander Lairson Costa <wander@redhat.com>
Link: https://lore.kernel.org/r/20251006143100.137255-1-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>

Tomas Glozar e4240db9 b4275b23

+3
+3
tools/tracing/rtla/src/timerlat.bpf.c
··· 148 148 } else { 149 149 update_main_hist(&hist_user, bucket); 150 150 update_summary(&summary_user, latency, bucket); 151 + 152 + if (thread_threshold != 0 && latency_us >= thread_threshold) 153 + set_stop_tracing(); 151 154 } 152 155 153 156 return 0;