Re: [dpdk-dev] [PATCH] event/dsw: use custom element size ring forcontrol

["Morten Brørup" <mb@smartsharesystems.com>]

> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Mattias Rönnblom
> Sent: Monday, January 20, 2020 4:03 PM
> 
> Replace DSW's use of regular DPDK rings (and code for
> packing/unpacking control messages into void pointers) with custom
> size rings.
> 
> In addition to cleaner code, this change allows DSW to support up to
> the eventdev API's maximum of 255 ports by tweaking DSW_MAX_PORTS.

Considering that the mbuf port_id was increased from 8 to 16 bit a long time ago... does it make sense increasing this and perhaps the eventdev API's type from 8 to 16 bit too?

> 
> Signed-off-by: Mattias Rönnblom <mattias.ronnblom@ericsson.com>
> ---
>  drivers/event/dsw/Makefile    |  3 +++
>  drivers/event/dsw/dsw_evdev.c |  9 ++++++---
>  drivers/event/dsw/dsw_evdev.h | 10 +++-------
>  drivers/event/dsw/dsw_event.c | 16 ++--------------
>  drivers/event/dsw/meson.build |  3 +++
>  5 files changed, 17 insertions(+), 24 deletions(-)
> 

[snip]

> diff --git a/drivers/event/dsw/dsw_evdev.h
> b/drivers/event/dsw/dsw_evdev.h
> index dc28ab125..5c7b6108d 100644
> --- a/drivers/event/dsw/dsw_evdev.h
> +++ b/drivers/event/dsw/dsw_evdev.h
> @@ -10,7 +10,6 @@
> 
>  #define DSW_PMD_NAME RTE_STR(event_dsw)
> 
> -/* Code changes are required to allow more ports. */
>  #define DSW_MAX_PORTS (64)

64 or 256?

>  #define DSW_MAX_PORT_DEQUEUE_DEPTH (128)
>  #define DSW_MAX_PORT_ENQUEUE_DEPTH (128)
> @@ -226,15 +225,12 @@ struct dsw_evdev {
>  #define DSW_CTL_UNPAUS_REQ (1)
>  #define DSW_CTL_CFM (2)
> 
> -/* sizeof(struct dsw_ctl_msg) must be equal or less than
> - * sizeof(void *), to fit on the control ring.
> - */
>  struct dsw_ctl_msg {
> -	uint8_t type:2;
> -	uint8_t originating_port_id:6;
> +	uint8_t type;
> +	uint8_t originating_port_id;
>  	uint8_t queue_id;
>  	uint16_t flow_hash;
> -} __rte_packed;
> +} __rte_aligned(4);

[snip]


Med venlig hilsen / kind regards
- Morten Brørup