Different hardwares have different threasholds for usleep_val to
reliably trigger an prio inversion, add option --usleep to allow
specifying it at runtime, to facilitate testing of prio inheritance
on different platforms.
Signed-off-by: Shizhao Chen <shichen@xxxxxxxxxx>
---
src/pi_tests/pip_stress.8 | 6 +++++-
src/pi_tests/pip_stress.c | 10 ++++++++--
2 files changed, 13 insertions(+), 3 deletions(-)
diff --git a/src/pi_tests/pip_stress.8 b/src/pi_tests/pip_stress.8
index 0d06dd2..f55e2d8 100644
--- a/src/pi_tests/pip_stress.8
+++ b/src/pi_tests/pip_stress.8
@@ -5,7 +5,8 @@
.B pip_stress \- Priority Inheritance with processes
.SH SYNOPSIS
.B pip_stress
-
+.RB [ \-u|\-\-usleep
+.IR TIME ]
.SH DESCRIPTION
This program demonstrates the technique of using priority inheritance (PI)
mutexes with processes instead of threads.
@@ -41,6 +42,9 @@ merely increase the time that the low priority process sleeps while
holding the lock. (usleep);
Also note that you have to run as a user with permission to change
scheduling priorities.
+.SH OPTIONS
+.IP "\-u TIME,\-\-usleep=TIME"
+Specify the sleep time of the low priority process. Defaults to 500(us).
.BR
.SH AUTHOR
pip_stress was written by John Kacur <jkacur at redhat.com>
diff --git a/src/pi_tests/pip_stress.c b/src/pi_tests/pip_stress.c
index fb0391b..782e5db 100644
--- a/src/pi_tests/pip_stress.c
+++ b/src/pi_tests/pip_stress.c
@@ -72,7 +72,9 @@ static void usage(int error)
printf("pip_stress V %1.2f\n", VERSION);
printf("Usage:\n"
"pip_stress <options>\n"\
- "-h --help Show this help menu.\n"
+ "-h --help Show this help menu.\n"\
+ "-u TIME --usleep=TIME Specify the sleep time of the low priority process.\n"\
+ " Defaults to 500(us).\n"
);
exit(error);
}
@@ -88,16 +90,20 @@ int main(int argc, char *argv[])
for (;;) {
struct option long_options[] = {
{ "help", no_argument, NULL, 'h' },
+ { "usleep", required_argument, NULL, 'u' },
{ NULL, 0, NULL, 0 },
};
- int c = getopt_long(argc, argv, "s:h", long_options, NULL);
+ int c = getopt_long(argc, argv, "hu:", long_options, NULL);
if (c == -1)
break;
switch (c) {
case 'h':
usage(0);
break;
+ case 'u':
+ usleep_val = (useconds_t)strtoul(optarg, NULL, 10);
+ break;
default:
usage(1);
break;
--
2.47.1
