[dpdk-dev] [PATCH v1] doc: update definition of lcore id and lcore index

Bruce Richardson bruce.richardson at intel.com
Thu Feb 1 16:04:51 CET 2018


On Wed, Jan 31, 2018 at 04:46:46PM +0000, Marko Kovacevic wrote:
> Added examples in lcore index for better
> explanation on various examples,
> Sited examples for lcore id.
> 
> Signed-off-by: Marko Kovacevic <marko.kovacevic at intel.com>
> ---
>  lib/librte_eal/common/include/rte_lcore.h | 17 +++++++++++++++--
>  1 file changed, 15 insertions(+), 2 deletions(-)
> 
> diff --git a/lib/librte_eal/common/include/rte_lcore.h b/lib/librte_eal/common/include/rte_lcore.h
> index d84bcff..349ac36 100644
> --- a/lib/librte_eal/common/include/rte_lcore.h
> +++ b/lib/librte_eal/common/include/rte_lcore.h
> @@ -57,7 +57,9 @@ RTE_DECLARE_PER_LCORE(unsigned, _lcore_id);  /**< Per thread "lcore id". */
>  RTE_DECLARE_PER_LCORE(rte_cpuset_t, _cpuset); /**< Per thread "cpuset". */
>  
>  /**
> - * Return the ID of the execution unit we are running on.
> + * Return the Application thread ID of the execution unit.
> + * If option '-l' or '-c' is provided the lcore ID is the actual
> + * CPU ID.

Good idea to clarify this!
I'd suggest the second sentence might do with being reworked a little
though - the lcore ID will also be the processor id even if no args i.e.
no -c or -l arguments are passed.

How about:
 * Note: in most cases the lcore id returned here will also correspond
 *   to the processor id of the CPU on which the thread is pinned, this
 *   will not be the case if the user has explicitly changed the thread to
 *   core affinities using --lcores EAL argument e.g. --lcores '(0-3)@10'
 *   to run threads with lcore IDs 0, 1, 2 and 3 on physical core 10.

It's longer, I know, but hopefully a bit clearer for the user.

/Bruce


More information about the dev mailing list