diff options
author | Daniel Bristot de Oliveira <bristot@kernel.org> | 2022-05-10 12:45:24 +0300 |
---|---|---|
committer | Steven Rostedt (Google) <rostedt@goodmis.org> | 2022-05-27 04:13:00 +0300 |
commit | 4dd2aea24ed7613735664feadc9879d37f718c23 (patch) | |
tree | 69acae3a0763f90848c337899bbc37fb2dd79bab /kernel | |
parent | aa748949b4e665f473bc5abdc5f66029cb5f5522 (diff) | |
download | linux-4dd2aea24ed7613735664feadc9879d37f718c23.tar.xz |
tracing/timerlat: Print stacktrace in the IRQ handler if needed
If print_stack and stop_tracing_us are set, and stop_tracing_us is hit
with latency higher than or equal to print_stack, print the
stack at the IRQ handler as it is useful to define the root cause for
the IRQ latency.
Link: https://lkml.kernel.org/r/fd04530ce98ae9270e41bb124ee5bf67b05ecfed.1652175637.git.bristot@kernel.org
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/trace/trace_osnoise.c | 13 |
1 files changed, 13 insertions, 0 deletions
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); } |