Re: [PATCH i-g-t] benchmarks/gem_wsim: Randomise random seed

Tvrtko Ursulin
2019-05-17T08:28:46Z

On 16/05/2019 19:58, Chris Wilson wrote:
> To avoid hitting the same rut on each benchmark run, start with a new
> random seed. To allow hitting the same rut again, let it be specified
> by the user.
>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
> ---
> benchmarks/gem_wsim.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/benchmarks/gem_wsim.c b/benchmarks/gem_wsim.c
> index 48568ce40..cf2a44746 100644
> --- a/benchmarks/gem_wsim.c
> +++ b/benchmarks/gem_wsim.c
> @@ -2282,8 +2282,9 @@ int main(int argc, char **argv)
> igt_require(fd);
>
> init_clocks();
> + srand(time(NULL));
>
> - while ((c = getopt(argc, argv, "hqv2RSHxGdc:n:r:w:W:a:t:b:p:")) != -1) {
> + while ((c = getopt(argc, argv, "hqv2RSHxGdc:n:r:w:W:a:t:b:p:s:")) != -1) {
> switch (c) {
> case 'W':
> if (master_workload >= 0) {
> @@ -2300,6 +2301,9 @@ int main(int argc, char **argv)
> case 'p':
> prio = atoi(optarg);
> break;
> + case 's':
> + srand(atoi(optarg));
> + break;
> case 'a':
> if (append_workload_arg) {
> if (verbose)
>

Makes sense, just the help text missing.

I was initially confused at srand when I thought I used your
hars_petruska library routines but then saw rand() feeds the seed into
those.