HI Ferruh, > -----Original Message----- > From: dev [mailto:dev-boun...@dpdk.org] On Behalf Of Ferruh Yigit > Sent: Monday, October 15, 2018 11:21 PM > To: Richardson, Bruce <bruce.richard...@intel.com> > Cc: dev@dpdk.org; Yigit, Ferruh <ferruh.yi...@intel.com>; > step...@networkplumber.org > Subject: [dpdk-dev] [PATCH v2 1/2] eal: add API that sleeps while waiting for > threads > > It is common that sample applications call rte_eal_wait_lcore() while > waiting for worker threads to be terminated. > Mostly master lcore keeps waiting in this function. > > The waiting app for termination is not a time critical task, app can > prefer a sleep version of the waiting to consume less cycles. > > A sleeping version of the API, rte_eal_wait_lcore_sleep(), has been > added which uses pthread conditions. > > Sample applications will be updated later to use this API. > > Signed-off-by: Ferruh Yigit <ferruh.yi...@intel.com> > --- > v2: > * use pthread cond instead of usleep > --- > lib/librte_eal/bsdapp/eal/eal.c | 3 +++ > lib/librte_eal/bsdapp/eal/eal_thread.c | 7 ++++++ > lib/librte_eal/common/eal_common_launch.c | 22 ++++++++++++++++++ > lib/librte_eal/common/include/rte_launch.h | 26 ++++++++++++++++++++++ > lib/librte_eal/common/include/rte_lcore.h | 3 +++ > lib/librte_eal/linuxapp/eal/eal.c | 3 +++ > lib/librte_eal/linuxapp/eal/eal_thread.c | 7 ++++++ > lib/librte_eal/rte_eal_version.map | 1 + > 8 files changed, 72 insertions(+) > > diff --git a/lib/librte_eal/bsdapp/eal/eal.c b/lib/librte_eal/bsdapp/eal/eal.c > index 7735194a3..e7d676657 100644 > --- a/lib/librte_eal/bsdapp/eal/eal.c > +++ b/lib/librte_eal/bsdapp/eal/eal.c > @@ -756,6 +756,9 @@ rte_eal_init(int argc, char **argv) > snprintf(thread_name, sizeof(thread_name), > "lcore-slave-%d", i); > rte_thread_setname(lcore_config[i].thread_id, thread_name); > + > + pthread_mutex_init(&rte_eal_thread_mutex[i], NULL); > + pthread_cond_init(&rte_eal_thread_cond[i], NULL); > } > > /* > diff --git a/lib/librte_eal/bsdapp/eal/eal_thread.c > b/lib/librte_eal/bsdapp/eal/eal_thread.c > index 309b58726..60db32d57 100644 > --- a/lib/librte_eal/bsdapp/eal/eal_thread.c > +++ b/lib/librte_eal/bsdapp/eal/eal_thread.c > @@ -28,6 +28,9 @@ RTE_DEFINE_PER_LCORE(unsigned, _lcore_id) = LCORE_ID_ANY; > RTE_DEFINE_PER_LCORE(unsigned, _socket_id) = (unsigned)SOCKET_ID_ANY; > RTE_DEFINE_PER_LCORE(rte_cpuset_t, _cpuset); > > +pthread_cond_t rte_eal_thread_cond[RTE_MAX_LCORE]; > +pthread_mutex_t rte_eal_thread_mutex[RTE_MAX_LCORE];
I think would be better to include cond and mutex into struct lcore_config itself, probably would help to avoid false sharing. Though yeh, it would mean ABI breakage, I suppose. > + > /* > * Send a message to a slave lcore identified by slave_id to call a > * function f with argument arg. Once the execution is done, the > @@ -154,6 +157,10 @@ eal_thread_loop(__attribute__((unused)) void *arg) > lcore_config[lcore_id].ret = ret; > rte_wmb(); > lcore_config[lcore_id].state = FINISHED; > + > + pthread_mutex_lock(&rte_eal_thread_mutex[lcore_id]); > + pthread_cond_signal(&rte_eal_thread_cond[lcore_id]); > + pthread_mutex_unlock(&rte_eal_thread_mutex[lcore_id]); I understand it would work that way too, but if you introduce mutex and cond around the state, then it is better to manipulate/access the state after grabbing the mutex. BTW in that case we don't need wmb: lcore_config[lcore_id].ret = ret; pthread_mutex_lock(...); lcore_config[lcore_id].state = FINISHED; pthread_cond_signal(..); pthread_mutex_unlock(...); Konstantin
