On Tue, 24 Mar 2026 13:32:29 +0100 Tomas Glozar <[email protected]> wrote:
> The behavior of RTLA on receiving SIGINT is currently undocumented. > > Describe it in RTLA's common appendix that appears in man pages for all > RTLA tools to avoid confusion. > > Suggested-by: Attila Fazekas <[email protected]> > Signed-off-by: Tomas Glozar <[email protected]> > --- > > Note: There was a bug in SIGINT behavior, fixed in upcoming commit [1]. > > [1] > https://lore.kernel.org/linux-trace-kernel/[email protected]/ Hmm, this may be interesting enough to add to the change log itself. > > Documentation/tools/rtla/common_appendix.txt | 21 ++++++++++++++++++++ > 1 file changed, 21 insertions(+) > > diff --git a/Documentation/tools/rtla/common_appendix.txt > b/Documentation/tools/rtla/common_appendix.txt > index 53cae7537537..8c90a02588e7 100644 > --- a/Documentation/tools/rtla/common_appendix.txt > +++ b/Documentation/tools/rtla/common_appendix.txt > @@ -1,5 +1,26 @@ > .. SPDX-License-Identifier: GPL-2.0 > > +SIGINT BEHAVIOR > +=============== > + > +On the first SIGINT, RTLA exits after collecting all outstanding samples up > to > +the point of receiving the signal. > + > +When receiving more than one SIGINT, RTLA discards any outstanding samples, > and > +exits while displaying only samples that have already been processed. > + > +If SIGINT is received during RTLA cleanup, RTLA exits immediately via > +the default signal handler. > + > +Note: For the purpose of SIGINT behavior, the expiry of duration specified > via > +the -d/--duration option is treated as equivalent to receiving a SIGINT. For > +example, a SIGINT received after duration expired but samples have not been > +processed yet will drop any outstanding samples. > + > +Also note that when using the timerlat tool in BPF mode, samples are > processed > +in-kernel; RTLA only copies them out to display them to the user. A second > +SIGINT does not affect in-kernel sample aggregation. But does it affect the user space side of reading that information? > + > EXIT STATUS > =========== > Other than that ... LGTM, Reviewed-by: Steven Rostedt (Google) <[email protected]> -- Steve
