Re: [dpdk-dev] [RFC 19.11 v2 1/3] ethdev: hide key ethdev structures from public API

["Zapolski, MarcinX A" <marcinx.a.zapolski@intel.com>]

> -----Original Message-----
> From: Yigit, Ferruh
> Sent: Monday, September 9, 2019 12:24 PM
> To: Zapolski, MarcinX A <marcinx.a.zapolski@intel.com>; dev@dpdk.org
> Cc: Jerin Jacob <jerin.jacob@caviumnetworks.com>; Laatz, Kevin
> <kevin.laatz@intel.com>
> Subject: Re: [dpdk-dev] [RFC 19.11 v2 1/3] ethdev: hide key ethdev
> structures from public API
> 
> On 9/9/2019 11:02 AM, Zapolski, MarcinX A wrote:
> >> -----Original Message-----
> >> From: Yigit, Ferruh
> >> Sent: Monday, September 9, 2019 12:00 PM
> >> To: Zapolski, MarcinX A <marcinx.a.zapolski@intel.com>; dev@dpdk.org
> >> Subject: Re: [dpdk-dev] [RFC 19.11 v2 1/3] ethdev: hide key ethdev
> >> structures from public API
> >>
> >> On 9/9/2019 9:07 AM, Zapolski, MarcinX A wrote:
> >>>> -----Original Message-----
> >>>> From: Yigit, Ferruh
> >>>> Sent: Friday, September 6, 2019 4:38 PM
> >>>> To: Zapolski, MarcinX A <marcinx.a.zapolski@intel.com>;
> >>>> dev@dpdk.org
> >>>> Subject: Re: [dpdk-dev] [RFC 19.11 v2 1/3] ethdev: hide key ethdev
> >>>> structures from public API
> >>>>
> >>>> On 9/6/2019 2:18 PM, Marcin Zapolski wrote:
> >>>>> Split rte_eth_dev structure to two parts: head that is available
> >>>>> for user applications, and rest which is DPDK internal.
> >>>>> Make an array of pointers to rte_eth_dev structures available for
> >>>>> user applications.
> >>>>>
> >>>>> Signed-off-by: Marcin Zapolski <marcinx.a.zapolski@intel.com>
> >>>>
> >>>> <...>
> >>>>
> >>>>> diff --git a/lib/librte_bitratestats/rte_bitrate.c
> >>>>> b/lib/librte_bitratestats/rte_bitrate.c
> >>>>> index 639e47547..82d469514 100644
> >>>>> --- a/lib/librte_bitratestats/rte_bitrate.c
> >>>>> +++ b/lib/librte_bitratestats/rte_bitrate.c
> >>>>> @@ -3,7 +3,7 @@
> >>>>>   */
> >>>>>
> >>>>>  #include <rte_common.h>
> >>>>> -#include <rte_ethdev.h>
> >>>>> +#include <rte_ethdev_driver.h>
> >>>>
> >>>> This is in the library, not sure if libraries should include the
> >>>> header file for the drivers, can you please explain why this change
> >>>> is
> >> needed?
> >>>>
> >>> It is needed to make rte_eth_dev structure available. But yes, I
> >>> agree that
> >> it will be more appropriate to include rte_ethdev.h and
> >> rte_ethdev_core.h separately. I probably wanted less includes, silly me.
> >>>> <...>
> >>>>
> >>>>> @@ -6,6 +6,7 @@
> >>>>>  #define _RTE_ETHDEV_PROFILE_H_
> >>>>>
> >>>>>  #include "rte_ethdev.h"
> >>>>> +#include "rte_ethdev_core.h"
> >>>>>
> >>>>>  /**
> >>>>>   * Initialization of the Ethernet device profiling.
> >>>>> diff --git a/lib/librte_ethdev/rte_ethdev.c
> >>>>> b/lib/librte_ethdev/rte_ethdev.c index 17d183e1f..5c6cc640a 100644
> >>>>> --- a/lib/librte_ethdev/rte_ethdev.c
> >>>>> +++ b/lib/librte_ethdev/rte_ethdev.c
> >>>>> @@ -40,6 +40,7 @@
> >>>>>
> >>>>>  #include "rte_ether.h"
> >>>>>  #include "rte_ethdev.h"
> >>>>> +#include "rte_ethdev_core.h"
> >>>>>  #include "rte_ethdev_driver.h"
> >>>>>  #include "ethdev_profile.h"
> >>>>>  #include "ethdev_private.h"
> >>>>
> >>>> I was hoping "rte_ethdev_core.h" can be removed completely by
> >>>> distributing its content to "ethdev_private.h", "rte_ethdev_driver.h"
> >>>> and perhaps even to "rte_ethdev.h".
> >>>>
> >>>> Can you please explain what prevents removing "rte_ethdev_core.h"?
> >>> I could rename it to rte_ethdev_private. There is just rte_eth_dev
> >>> and
> >> rte_eth_dev_data left in it.
> >>>
> >>
> >> I think drivers access to both 'rte_eth_dev' and 'rte_eth_dev_data'
> >> so can't move them to 'ethdev_private.h' why not move it to
> 'rte_ethdev_driver.h'?
> >
> > Because the libraries use them as well.
> >
> 
> These are 'librte_ethdev' library internal data, I think other libraries shouldn't
> access them directly.
> 
> As far as I can see,
> librte_eventdev  => rte_eth_dev_data
> librte_eventdev  => rte_eth_dev
> librte_telemetry => rte_eth_dev
> 
> Can you see any other library accessing 'rte_eth_dev' and
> 'rte_eth_dev_data' ?
> 
No, no others.
> 
> I am not sure about 'eventdev', specially because of the Rx/Tx adapters of it,
> perhaps they can include the "rte_ethdev_driver.h", cc'ed Jerin.
> 
> I didn't check the telemetry code, but I assume it can be fixed too, but for
> now "rte_ethdev_driver.h" can be included to highlight something is wrong
> there.
> 
> And related "ethdev_private.h", as far as I understand it is not private to all
> libraries, it is private to the ethdev library, which means only should be used
> to share the definitions withing ethdev library .c files. So no other library
> should include it.
> 
Agreed, will take it into account for v3.