Re: [dpdk-dev] [PATCH v2 4/4] lib: reduce global variable usage

[Shreyansh Jain <shreyansh.jain@nxp.com>]

On Friday 05 October 2018 09:56 PM, Ferruh Yigit wrote:
> Some global variables can be eliminated, since they are not part of
> public interface, it is free to remove them.
> 
> Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
> ---
>   lib/librte_compressdev/rte_compressdev.c     | 32 ++++++++----------
>   lib/librte_compressdev/rte_compressdev_pmd.h |  5 ---
>   lib/librte_cryptodev/rte_cryptodev.c         | 34 +++++++++-----------
>   lib/librte_cryptodev/rte_cryptodev_pmd.h     |  3 --
>   lib/librte_eventdev/rte_eventdev.c           |  8 ++---
>   lib/librte_eventdev/rte_eventdev_pmd.h       |  2 --
>   lib/librte_rawdev/rte_rawdev.c               | 10 +++---
>   lib/librte_rawdev/rte_rawdev_pmd.h           |  2 --
>   8 files changed, 37 insertions(+), 59 deletions(-)

[...]

> diff --git a/lib/librte_rawdev/rte_rawdev.c b/lib/librte_rawdev/rte_rawdev.c
> index 62b6b97ef..9f1e3592d 100644
> --- a/lib/librte_rawdev/rte_rawdev.c
> +++ b/lib/librte_rawdev/rte_rawdev.c
> @@ -35,21 +35,19 @@
>   /* dynamic log identifier */
>   int librawdev_logtype;
>   
> -struct rte_rawdev rte_rawdevices[RTE_RAWDEV_MAX_DEVS];
> +static struct rte_rawdev rte_rawdevices[RTE_RAWDEV_MAX_DEVS];
>   
> -struct rte_rawdev *rte_rawdevs = &rte_rawdevices[0];
> +struct rte_rawdev *rte_rawdevs = rte_rawdevices;
>   
>   static struct rte_rawdev_global rawdev_globals = {
>   	.nb_devs		= 0
>   };
>   
> -struct rte_rawdev_global *rte_rawdev_globals = &rawdev_globals;
> -
>   /* Raw device, northbound API implementation */
>   uint8_t
>   rte_rawdev_count(void)
>   {
> -	return rte_rawdev_globals->nb_devs;
> +	return rawdev_globals.nb_devs;
>   }
>   
>   uint16_t
> @@ -60,7 +58,7 @@ rte_rawdev_get_dev_id(const char *name)
>   	if (!name)
>   		return -EINVAL;
>   
> -	for (i = 0; i < rte_rawdev_globals->nb_devs; i++)
> +	for (i = 0; i < rawdev_globals.nb_devs; i++)
>   		if ((strcmp(rte_rawdevices[i].name, name)
>   				== 0) &&
>   				(rte_rawdevices[i].attached ==
> diff --git a/lib/librte_rawdev/rte_rawdev_pmd.h b/lib/librte_rawdev/rte_rawdev_pmd.h
> index bb9bbc350..811e51d07 100644
> --- a/lib/librte_rawdev/rte_rawdev_pmd.h
> +++ b/lib/librte_rawdev/rte_rawdev_pmd.h
> @@ -73,8 +73,6 @@ struct rte_rawdev_global {
>   	uint16_t nb_devs;
>   };
>   
> -extern struct rte_rawdev_global *rte_rawdev_globals;
> -/** Pointer to global raw devices data structure. */
>   extern struct rte_rawdev *rte_rawdevs;
>   /** The pool of rte_rawdev structures. */

I think `rte_rawdevs` can also be removed from an exposed symbol. In all 
cases (at least for now), this is being accessed using an API (and no 
macros). There should be no need for people to read this directly if 
sufficient get_by_* APIs are available.

Wouldn't same be valid for rte_compressdevs as well?

Besides the above:

Acked-by: Shreyansh Jain <shreyansh.jain@nxp.com>