Re: [dpdk-dev] [PATCH 1/2] service: add mechanism for quiescing a service

["Van Haaren, Harry" <harry.van.haaren@intel.com>]

> From: Eads, Gage
> Sent: Thursday, May 31, 2018 2:56 PM
> To: dev@dpdk.org
> Cc: jerin.jacob@caviumnetworks.com; Van Haaren, Harry
> <harry.van.haaren@intel.com>; Richardson, Bruce <bruce.richardson@intel.com>;
> Rao, Nikhil <nikhil.rao@intel.com>; Carrillo, Erik G
> <erik.g.carrillo@intel.com>; Gujjar, Abhinandan S
> <abhinandan.gujjar@intel.com>
> Subject: [PATCH 1/2] service: add mechanism for quiescing a service
> 
> Existing service functions allow us to stop a service, but doing so doesn't
> guarantee that the service has finished running on a service core. This
> commit introduces rte_service_may_be_active(), which returns whether the
> service may be executing on one or more lcores currently, or definitely is
> not.
> 
> The service core layer supports this function by setting a flag when
> a service core is going to execute a service, and unsetting the flag when
> the core is no longer able to run the service (its runstate becomes stopped
> or the lcore is no longer mapped).
> 
> With this new function, applications can set a service's runstate to
> stopped, then poll rte_service_may_be_active() until it returns false. At
> that point, the service is quiesced.
>
> Signed-off-by: Gage Eads <gage.eads@intel.com>


Good approach to the problem.

One nit below, version map should be alphabetical;

Acked-by: Harry van Haaren <harry.van.haaren@intel.com>


<snip>

> diff --git a/lib/librte_eal/rte_eal_version.map
> b/lib/librte_eal/rte_eal_version.map
> index f7dd0e7bc..6f38b02dc 100644
> --- a/lib/librte_eal/rte_eal_version.map
> +++ b/lib/librte_eal/rte_eal_version.map
> @@ -238,6 +238,7 @@ DPDK_18.05 {
>  	rte_service_set_runstate_mapped_check;
>  	rte_service_set_stats_enable;
>  	rte_service_start_with_defaults;
> +	rte_service_may_be_active;
> 
>  } DPDK_18.02;

Version map to be alphabetically ordered.