RE: [EXT] Re: [PATCH v5 1/2] eal: add API for bus close

[Rohit Raj <rohit.raj@nxp.com>]

Hi Thomas,

This "rte_bus_close" API is introduced to do the opposite of what "rte_bus_probe" does. Just like there are plug and unplug APIs for plugging and unplugging a single device.

The API you mentioned, "rte_dev_remove" supports only rte_device.  But we also need to close/remove private devices of dpaa and fslmc buses which are not exposed directly to user (eg: mempool device). 
Note that these private devices/bus objects are not associated with a particular rte_device but they are available as a resource to be used by any of the device based on these hardware specific buses. 
So, to close these devices, we need a new API which can do this for us. That is why "rte_bus_close" is required.

Regards,
Rohit Raj

> -----Original Message-----
> From: Thomas Monjalon <thomas@monjalon.net>
> Sent: Wednesday, January 19, 2022 4:02 PM
> To: Rohit Raj <rohit.raj@nxp.com>
> Cc: Bruce Richardson <bruce.richardson@intel.com>; Ray Kinsella
> <mdr@ashroe.eu>; Dmitry Kozlyuk <dmitry.kozliuk@gmail.com>; Narcisa Ana
> Maria Vasile <navasile@linux.microsoft.com>; Dmitry Malloy
> <dmitrym@microsoft.com>; Pallavi Kadam <pallavi.kadam@intel.com>;
> dev@dpdk.org; Nipun Gupta <nipun.gupta@nxp.com>; Sachin Saxena
> <sachin.saxena@nxp.com>; Hemant Agrawal <hemant.agrawal@nxp.com>;
> ferruh.yigit@intel.com; david.marchand@redhat.com
> Subject: [EXT] Re: [PATCH v5 1/2] eal: add API for bus close
> 
> Caution: EXT Email
> 
> Hi,
> 
> 10/01/2022 06:26, rohit.raj@nxp.com:
> > From: Rohit Raj <rohit.raj@nxp.com>
> >
> > As per the current code we have API for bus probe, but the bus close
> > API is missing. This breaks the multi process scenarios as objects are
> > not cleaned while terminating the secondary processes.
> >
> > This patch adds a new API rte_bus_close() for cleanup of bus objects
> > which were acquired during probe.
> 
> I don't understand how closing all devices of a bus will help better than just
> closing all devices.
> 
> As Ferruh already suggested in the past, we could force closing all devices in
> rte_eal_cleanup().
> And we already have the function rte_dev_remove().
> 
>