diff options
| -rw-r--r-- | Documentation/trace/timerlat-tracer.rst | 5 | ||||
| -rw-r--r-- | kernel/trace/trace_osnoise.c | 13 |
2 files changed, 16 insertions, 2 deletions
diff --git a/Documentation/trace/timerlat-tracer.rst b/Documentation/trace/timerlat-tracer.rst index 64d1fe6e9b93..d643c95c01eb 100644 --- a/Documentation/trace/timerlat-tracer.rst +++ b/Documentation/trace/timerlat-tracer.rst @@ -74,8 +74,9 @@ directory. The timerlat configs are: - stop_tracing_total_us: stop the system tracing if a timer latency at the *thread* context is higher than the configured value happens. Writing 0 disables this option. - - print_stack: save the stack of the IRQ occurrence, and print - it after the *thread context* event". + - print_stack: save the stack of the IRQ occurrence. The stack is printed + after the *thread context* event, or at the IRQ handler if *stop_tracing_us* + is hit. timerlat and osnoise ---------------------------- diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c index 6494ca27ea6f..9b204ee3c6f5 100644 --- a/kernel/trace/trace_osnoise.c +++ b/kernel/trace/trace_osnoise.c @@ -1580,6 +1580,19 @@ static enum hrtimer_restart timerlat_irq(struct hrtimer *timer) if (osnoise_data.stop_tracing) { if (time_to_us(diff) >= osnoise_data.stop_tracing) { + + /* + * At this point, if stop_tracing is set and <= print_stack, + * print_stack is set and would be printed in the thread handler. + * + * Thus, print the stack trace as it is helpful to define the + * root cause of an IRQ latency. + */ + if (osnoise_data.stop_tracing <= osnoise_data.print_stack) { + timerlat_save_stack(0); + timerlat_dump_stack(time_to_us(diff)); + } + osnoise_stop_tracing(); notify_new_max_latency(diff); } |