W dniu 20.07.2020 o 16:38, Harry van Haaren pisze:
> This commit adds a new experimental API which allows the user
> to retrieve the active state of an lcore. Knowing when the service
> lcore is completed its polling loop can be useful to applications
> to avoid race conditions when e.g. finalizing statistics.
>
> The service thread itself now has a variable to indicate if its
> thread is active. When zero the service thread has completed its
> service, and has returned from the service_runner_func() function.
>
> Suggested-by: Lukasz Wojciechowski <l.wojciec...@partner.samsung.com>
> Signed-off-by: Harry van Haaren <harry.van.haa...@intel.com>
>
> ---
>
> Thanks for feedback Lukasz, please have a look and see if this was
> what you were expecting?
>
> Honnappa/Phil, are the __atomic_load/store's correct?
>
> ---
> lib/librte_eal/common/rte_service.c | 14 ++++++++++++++
> lib/librte_eal/include/rte_service.h | 9 +++++++++
> lib/librte_eal/rte_eal_version.map | 1 +
> 3 files changed, 24 insertions(+)
>
> diff --git a/lib/librte_eal/common/rte_service.c
> b/lib/librte_eal/common/rte_service.c
> index 6a0e0ff65..4c276b006 100644
> --- a/lib/librte_eal/common/rte_service.c
> +++ b/lib/librte_eal/common/rte_service.c
> @@ -65,6 +65,7 @@ struct core_state {
> /* map of services IDs are run on this core */
> uint64_t service_mask;
> uint8_t runstate; /* running or stopped */
> + uint8_t thread_active; /* indicates when thread is in service_run() */
> uint8_t is_service_core; /* set if core is currently a service core */
> uint8_t service_active_on_lcore[RTE_SERVICE_NUM_MAX];
> uint64_t loops;
> @@ -457,6 +458,8 @@ service_runner_func(void *arg)
> const int lcore = rte_lcore_id();
> struct core_state *cs = &lcore_states[lcore];
>
> + __atomic_store_n(&cs->thread_active, 1, __ATOMIC_RELAXED);
> +
> /* runstate act as the guard variable. Use load-acquire
> * memory order here to synchronize with store-release
> * in runstate update functions.
> @@ -475,9 +478,20 @@ service_runner_func(void *arg)
> cs->loops++;
> }
>
> + __atomic_store_n(&cs->thread_active, 0, __ATOMIC_RELAXED);
> return 0;
> }
>
> +int32_t
> +rte_service_lcore_active(uint32_t lcore)
> +{
> + if (lcore >= RTE_MAX_LCORE || !lcore_states[lcore].is_service_core)
> + return -EINVAL;
> +
> + return __atomic_load_n(&lcore_states[lcore].thread_active,
> + __ATOMIC_RELAXED);
> +}
> +
> int32_t
> rte_service_lcore_count(void)
> {
> diff --git a/lib/librte_eal/include/rte_service.h
> b/lib/librte_eal/include/rte_service.h
> index e2d0a6dd3..f7134b5c0 100644
> --- a/lib/librte_eal/include/rte_service.h
> +++ b/lib/librte_eal/include/rte_service.h
> @@ -261,6 +261,15 @@ int32_t rte_service_lcore_start(uint32_t lcore_id);
> */
> int32_t rte_service_lcore_stop(uint32_t lcore_id);
>
> +/**
> + * Reports if a service lcore is currently running.
> + * @retval 0 Service thread is not active, and has been returned to EAL.
> + * @retval 1 Service thread is in the service core polling loop.
> + * @retval -EINVAL Invalid *lcore_id* provided.
> + */
> +__rte_experimental
> +int32_t rte_service_lcore_active(uint32_t lcore_id);
> +
> /**
> * Adds lcore to the list of service cores.
> *
> diff --git a/lib/librte_eal/rte_eal_version.map
> b/lib/librte_eal/rte_eal_version.map
> index bf0c17c23..d53d5d5b9 100644
> --- a/lib/librte_eal/rte_eal_version.map
> +++ b/lib/librte_eal/rte_eal_version.map
> @@ -401,6 +401,7 @@ EXPERIMENTAL {
> rte_lcore_dump;
> rte_lcore_iterate;
> rte_mp_disable;
> + rte_service_lcore_active;
> rte_thread_register;
> rte_thread_unregister;
> };
Acked-by: Lukasz Wojciechowski <l.wojciec...@partner.samsung.com>
--
Lukasz Wojciechowski
Principal Software Engineer
Samsung R&D Institute Poland
Samsung Electronics
Office +48 22 377 88 25
l.wojciec...@partner.samsung.com
