[dpdk-dev] [PATCH 01/22] eal: introduce one device scan

[Zhang, Qi Z]

Hi Shreyansh:
	Thanks for your review.
	Will fix base on your comments in v2.
Regards
Qi

> -----Original Message-----
> From: Shreyansh Jain [mailto:shreyansh.jain at nxp.com]
> Sent: Friday, June 8, 2018 7:12 PM
> To: Zhang, Qi Z <qi.z.zhang at intel.com>
> Cc: thomas at monjalon.net; Burakov, Anatoly <anatoly.burakov at intel.com>;
> Ananyev, Konstantin <konstantin.ananyev at intel.com>; dev at dpdk.org;
> Richardson, Bruce <bruce.richardson at intel.com>; Yigit, Ferruh
> <ferruh.yigit at intel.com>; Shelton, Benjamin H
> <benjamin.h.shelton at intel.com>; Vangati, Narender
> <narender.vangati at intel.com>
> Subject: Re: [dpdk-dev] [PATCH 01/22] eal: introduce one device scan
> 
> On 6/7/2018 6:08 PM, Qi Zhang wrote:
> > When hot plug a new device, it is not necessary to scan everything on
> > the bus since the devname and devargs are already there. So new
> > rte_bus ops "scan_one" is introduced, bus driver can implement this
> > function to simply the hotplug process.
>               ^^^^^^^^^
>               simplify
> 
> >
> > Signed-off-by: Qi Zhang <qi.z.zhang at intel.com>
> > ---
> >   lib/librte_eal/common/eal_common_dev.c  | 17 +++++++++++++----
> >   lib/librte_eal/common/include/rte_bus.h |  4 ++++
> >   2 files changed, 17 insertions(+), 4 deletions(-)
> >
> > diff --git a/lib/librte_eal/common/eal_common_dev.c
> > b/lib/librte_eal/common/eal_common_dev.c
> > index 61cb3b162..1ad033536 100644
> > --- a/lib/librte_eal/common/eal_common_dev.c
> > +++ b/lib/librte_eal/common/eal_common_dev.c
> > @@ -147,11 +147,20 @@ int __rte_experimental
> rte_eal_hotplug_add(const char *busname, const char *devn
> >   	if (ret)
> >   		goto err_devarg;
> >
> > -	ret = bus->scan();
> > -	if (ret)
> > -		goto err_devarg;
> > +	/**
> > +	 * if bus support to scan specific device by devargs,
> > +	 * we don't need to scan all devices on the bus.
> > +	 */
> > +	if (bus->scan_one) {
> > +		dev = bus->scan_one(da);
> > +	} else {
> > +		ret = bus->scan();
> > +		if (ret)
> > +			goto err_devarg;
> > +
> > +		dev = bus->find_device(NULL, cmp_detached_dev_name,
> devname);
> > +	}
> >
> > -	dev = bus->find_device(NULL, cmp_detached_dev_name, devname);
> >   	if (dev == NULL) {
> >   		RTE_LOG(ERR, EAL, "Cannot find unplugged device (%s)\n",
> >   			devname);
> > diff --git a/lib/librte_eal/common/include/rte_bus.h
> > b/lib/librte_eal/common/include/rte_bus.h
> > index eb9eded4e..b15cff892 100644
> > --- a/lib/librte_eal/common/include/rte_bus.h
> > +++ b/lib/librte_eal/common/include/rte_bus.h
> > @@ -83,6 +83,7 @@ enum rte_iova_mode {
> >    */
> >   typedef int (*rte_bus_scan_t)(void);
> >
> > +typedef struct rte_device *(*rte_bus_scan_one_t)(struct rte_devargs
> > +*);
> 
> You should add comments over the declaration, just like the other similar
> declarations.
> And, a new line should be here.
> 
> >   /**
> >    * Implementation specific probe function which is responsible for
> linking
> >    * devices on that bus with applicable drivers.
> > @@ -95,6 +96,8 @@ typedef int (*rte_bus_scan_t)(void);
> >    */
> >   typedef int (*rte_bus_probe_t)(void);
> >
> > +
> > +
> 
> And please remove the extra lines added above in next version of patch.
> 
> >   /**
> >    * Device iterator to find a device on a bus.
> >    *
> > @@ -204,6 +207,7 @@ struct rte_bus {
> >   	TAILQ_ENTRY(rte_bus) next;   /**< Next bus object in linked list
> */
> >   	const char *name;            /**< Name of the bus */
> >   	rte_bus_scan_t scan;         /**< Scan for devices attached to
> bus */
> > +	rte_bus_scan_one_t scan_one; /**< Scan one device by devargs */
> 
> I think you mean "Scan one device using devargs" rather than "Scan one
> device by devargs".
> 
> >   	rte_bus_probe_t probe;       /**< Probe devices on bus */
> >   	rte_bus_find_device_t find_device; /**< Find a device on the bus
> */
> >   	rte_bus_plug_t plug;         /**< Probe single device for drivers
> */
> >