When using a POSIX interval timer and an overrun occurs, a signal is always
lost. From then on cyclictest would report all measurements as increased by
N*period (where N is the number of overruns).
cyclictest can detect the overruns and adjust the expected time of the next
tick accordingly.
Reported-by: Marti Raudsepp <marti@xxxxxxxxx>
Signed-off-by: Michal Schmidt <mschmidt@xxxxxxxxxx>
---
src/cyclictest/cyclictest.c | 5 +++++
1 files changed, 5 insertions(+), 0 deletions(-)
diff --git a/src/cyclictest/cyclictest.c b/src/cyclictest/cyclictest.c
index 3a7e752..6829d34 100644
--- a/src/cyclictest/cyclictest.c
+++ b/src/cyclictest/cyclictest.c
@@ -713,6 +713,11 @@ void *timerthread(void *param)
next.tv_sec += interval.tv_sec;
next.tv_nsec += interval.tv_nsec;
+ if (par->mode == MODE_CYCLIC) {
+ int overrun_count = timer_getoverrun(timer);
+ next.tv_sec += overrun_count * interval.tv_sec;
+ next.tv_nsec += overrun_count * interval.tv_nsec;
+ }
tsnorm(&next);
if (par->max_cycles && par->max_cycles == stat->cycles)
--
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