Add the newly introduced --json command line to the man page.

Signed-off-by: Daniel Wagner <redacted>
---
 src/ptsematest/ptsematest.8 | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/ptsematest/ptsematest.8 b/src/ptsematest/ptsematest.8
index a435e7a6221c..57e1658612c0 100644
--- a/src/ptsematest/ptsematest.8
+++ b/src/ptsematest/ptsematest.8

@@ -4,7 +4,7 @@
 \fBptsematest\fR \- Start two threads and measure the latency of interprocess communication with POSIX mutex.
 .SH "SYNOPSIS"
 .LP
-ptsematest [-a|--affinity [PROC]] [-b|--breaktrace USEC] [-d|--distance DIST] [-D|--duration TIME] [-h|--help] [-i|--interval INTV] [-l|--loops LOOPS] [-p|--prio PRIO] [-q|--quiet] [-S|--smp] [-t|--threads [NUM]]
+ptsematest [-a|--affinity [PROC]] [-b|--breaktrace USEC] [-d|--distance DIST] [-D|--duration TIME] [-h|--help] [-i|--interval INTV] [--json FILENAME] [-l|--loops LOOPS] [-p|--prio PRIO] [-q|--quiet] [-S|--smp] [-t|--threads [NUM]]
 .br
 .SH "DESCRIPTION"
 .LP

@@ -32,6 +32,9 @@ Print help message.
 .B \-i, \-\-interval=INTV
 Set the base interval of the thread(s) in microseconds (default is 1000 us). This sets the interval of the first thread. See also -d.
 .TP
+.B \-\-json=FILENAME
+Write final results into FILENAME, JSON formatted.
+.TP
 .B \-l, \-\-loops=LOOPS
 Set the number of loops. The default is 0 (endless). This option is useful for automated tests with a given number of test cycles. ptsematest is stopped once the number of timer intervals has been reached.
 .TP

-- 
2.31.1