From: Pavan Nikhilesh Bhagavatula <pbhagavatula@caviumnetworks.com>
To: "Van Haaren, Harry" <harry.van.haaren@intel.com>
Cc: thomas@monjalon.net, dev@dpdk.org
Subject: Re: [dpdk-dev] [PATCH] eal: added new `rte_lcore_is_service_lcore` API.
Date: Fri, 15 Sep 2017 20:11:55 +0530 [thread overview]
Message-ID: <20170915144154.GA15346@PBHAGAVATULA-LT> (raw)
In-Reply-To: <E923DB57A917B54B9182A2E928D00FA640C7A141@IRSMSX102.ger.corp.intel.com>
On Fri, Sep 15, 2017 at 01:57:42PM +0000, Van Haaren, Harry wrote:
> > From: Thomas Monjalon [mailto:thomas@monjalon.net]
> > Sent: Friday, September 15, 2017 2:53 PM
> > To: Pavan Nikhilesh Bhagavatula <pbhagavatula@caviumnetworks.com>; Van Haaren,
> > Harry <harry.van.haaren@intel.com>
> > Cc: dev@dpdk.org
> > Subject: Re: [dpdk-dev] [PATCH] eal: added new `rte_lcore_is_service_lcore`
> > API.
> >
> > 28/08/2017 17:09, Pavan Nikhilesh Bhagavatula:
> > > On Mon, Aug 28, 2017 at 01:49:37PM +0000, Van Haaren, Harry wrote:
> > > > From: Pavan Nikhilesh Bhagavatula [mailto:pbhagavatula@caviumnetworks.com]
> > > > > On Mon, Aug 28, 2017 at 10:59:51AM +0000, Van Haaren, Harry wrote:
> > > > > > From: Pavan Nikhilesh [mailto:pbhagavatula@caviumnetworks.com]
> > > > > > > --- a/lib/librte_eal/common/include/rte_lcore.h
> > > > > > > +++ b/lib/librte_eal/common/include/rte_lcore.h
> > > > > > > @@ -180,6 +180,24 @@ rte_lcore_is_enabled(unsigned lcore_id)
> > > > > > > }
> > > > > > >
> > > > > > > /**
> > > > > > > + * Test if an lcore is service lcore.
> > > > > > > + *
> > > > > > > + * @param lcore_id
> > > > > > > + * The identifier of the lcore, which MUST be between 0 and
> > > > > > > + * RTE_MAX_LCORE-1.
> > > > > > > + * @return
> > > > > > > + * True if the given lcore is service; false otherwise.
> > > > > > > + */
> > > > > > > +static inline int
> > > > > > > +rte_lcore_is_service_lcore(unsigned lcore_id)
> > > > > > > +{
> > > > > > > + struct rte_config *cfg = rte_eal_get_configuration();
> > > > > > > + if (lcore_id >= RTE_MAX_LCORE)
> > > > > > > + return 0;
> > > > > > > + return cfg->lcore_role[lcore_id] == ROLE_SERVICE;
> > > > > > > +}
> > > > > >
> > > > > > No header file and Static inline - so this is only to be used
> > internally in the service
> > > > > cores library?
> > > > > > If so, the function should actually be used, instead of only added but
> > not used in the
> > > > > library itself.
> > > > > >
> > > > >
> > > > > The enum rte_lcore_role_t has ROLE_SERVICE which tells that a particular
> > lcore is
> > > > > a service lcore as well as an EAL thread some libraries such as rte_timer
> > allow
> > > > > specific operations only over EAL threads.
> > > >
> > > > Understood that role of cores is important, and that rte_timer might
> > require this information.
> > > >
> > > >
> > > > > The rte_timer lib uses the rte_is_lcore_enabled() call to check if a
> > lcore is an
> > > > > EAL thread, Which checks if the lcore role is ROLE_RTE. But it should
> > also
> > > > > allow timers to be registered on a service core as processing those
> > timers can
> > > > > be done on them.
> > > >
> > > > No problem from me here either - although it's the Timers library
> > maintainer that should check this.
> > > >
> > > >
> > > > > This new function allows such libraries to check if the role is
> > > > > ROLE_SERVICE and allow those operations.
> > > >
> > > > If the timers library requires information about service-cores, it should
> > use a public API to retrieve that information. Having "internal" functions
> > between libraries is not nice.
> > > >
> > > > I think a better design would be to add this function as a public function,
> > (add it to the .map files etc) and then call the public function from the
> > timers library.
> > > >
> > > > Does that sound like a good solution? -Harry
> > > >
> > >
> > > The file rte_lcore.h is in librte_eal/common/include I couldn't find a .map
> > > file for eal/common and also other functions that are present in rte_lcore.h
> > > aren't mapped in eal/linuxapp or eal/bsdapp.
> > > I think it is fine as the functions are static inline.
> >
> > We must avoid adding more inline functions without a good justification.
> > The inline functions are tolerated for performance reasons only.
> >
> > We could also choose to add this function to rte_service.h ?
>
> Yes that is an option, and OK with me.
>
> @Pavan what do you think of adding it to service.h, implement in .c and add to .map?
>
The ROLE_SERVICE/ROLE_RTE defines the role of a lcore so it made sense to put
it in rte_lcore.h as lcore properties are accessed mostly through this header.
I'm fine with adding it to service.h as suggested by Harry.
-Pavan
next prev parent reply other threads:[~2017-09-15 14:42 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-23 15:10 Pavan Nikhilesh
2017-08-28 10:59 ` Van Haaren, Harry
2017-08-28 11:33 ` Pavan Nikhilesh Bhagavatula
2017-08-28 13:49 ` Van Haaren, Harry
2017-08-28 15:09 ` Pavan Nikhilesh Bhagavatula
2017-08-28 15:24 ` Van Haaren, Harry
2017-08-28 15:43 ` Pavan Nikhilesh Bhagavatula
2017-08-29 13:17 ` Van Haaren, Harry
2017-08-29 13:44 ` Pavan Nikhilesh Bhagavatula
2017-09-15 13:52 ` Thomas Monjalon
2017-09-15 13:57 ` Van Haaren, Harry
2017-09-15 14:41 ` Pavan Nikhilesh Bhagavatula [this message]
2017-09-15 14:44 ` Van Haaren, Harry
2017-09-15 14:59 ` Pavan Nikhilesh Bhagavatula
2017-09-15 15:51 ` Thomas Monjalon
2017-09-15 17:37 ` Pavan Nikhilesh Bhagavatula
2017-09-20 14:53 ` Van Haaren, Harry
2017-09-20 15:53 ` Thomas Monjalon
2017-09-20 17:31 ` Pavan Nikhilesh Bhagavatula
2017-09-21 8:58 ` [dpdk-dev] [PATCH v2] eal: add function to check lcore role Pavan Nikhilesh
2017-09-21 9:41 ` Van Haaren, Harry
2017-09-21 10:03 ` Pavan Nikhilesh Bhagavatula
2017-09-21 10:59 ` [dpdk-dev] [PATCH v3] " Pavan Nikhilesh
2017-10-11 20:14 ` Thomas Monjalon
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