> -----Original Message----- > From: Stephen Hemminger <[email protected]> > Sent: Friday 11 September 2026 23:59 > To: [email protected] > Cc: Stephen Hemminger <[email protected]>; Mattias Rönnblom > <[email protected]> > Subject: [RFC] eal: allow setting random number generator seed > > Many performance tests use rte_rand() and the random number > can perturb the results. Add an ability to overide the automatic > random seed on DPDK startup. > > This is not a security problem since rte_rand() is documented > as not being cryptographically secure. > > Signed-off-by: Stephen Hemminger <[email protected]> > --- > lib/eal/common/rte_random.c | 13 ++++++++++++- > 1 file changed, 12 insertions(+), 1 deletion(-) > > diff --git a/lib/eal/common/rte_random.c b/lib/eal/common/rte_random.c > index 576a32a46c..cdad60049b 100644 > --- a/lib/eal/common/rte_random.c > +++ b/lib/eal/common/rte_random.c > @@ -247,7 +247,18 @@ eal_rand_init(void) > > RTE_LCORE_VAR_ALLOC(rand_state); > > - seed = __rte_random_initial_seed(); > + const char *env = getenv("DPDK_RANDOM_SEED"); > + if (env != NULL && *env != '\0') { > + char *end; > + > + errno = 0; > + seed = strtoull(env, &end, 0); > + if (errno != 0 || *end != '\0') > + rte_exit(EXIT_FAILURE, > + "invalid DPDK_RANDOM_SEED: %s\n", env); > + } else { > + seed = __rte_random_initial_seed(); > + } > > rte_srand(seed); > } > -- > 2.53.0
Lgtm, although as a minor nit `env` is maybe not the best name here. Regardless, Acked-by: Marat Khalili <[email protected]>
