On Fri, 24 Jan 2025, Shizhao Chen wrote:
> 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..0f65ad1 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 in usec of the low priority process. Defaults to 500.
> .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..9bd225f 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 in usec of the low priority process.\n"\
> + " Defaults to 500.\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 = strtoul(optarg, NULL, 10);
> + break;
> default:
> usage(1);
> break;
> --
> 2.47.1
>
>
>
Signed-off-by: John Kacur <jkacur@xxxxxxxxxx>
