Re: [dpdk-dev] [PATCH v2 2/2] eal: rename dev init API for consistency

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

On Monday 05 December 2016 03:54 PM, Jerin Jacob wrote:
> On Mon, Dec 05, 2016 at 03:42:18PM +0530, Shreyansh Jain wrote:
>> Hello Jerin,
>
> Hello Shreyansh,
>
>>
>> On Sunday 04 December 2016 02:25 AM, Jerin Jacob wrote:
>>> rte_eal_dev_init() is a misleading name.
>>> It actually performs the driver->probe for vdev,
>>> which is parallel to rte_eal_pci_probe.
>>>
>>> Changed to rte_eal_vdev_probe for consistency and
>>> moved the vdev specific probe to eal_common_vdev.c
>>>
>>> Suggested-by: Shreyansh Jain <shreyansh.jain@nxp.com>
>>> Signed-off-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
>>> ---
>>> +int
>>> +rte_eal_vdev_probe(void)
>>> +{
>>> +	struct rte_devargs *devargs;
>>> +
>>> +	/*
>>> +	 * Note that the dev_driver_list is populated here
>>> +	 * from calls made to rte_eal_driver_register from constructor functions
>>> +	 * embedded into PMD modules via the RTE_PMD_REGISTER_VDEV macro
>>> +	 */
>>> +
>>> +	/* call the init function for each virtual device */
>>> +	TAILQ_FOREACH(devargs, &devargs_list, next) {
>>> +
>>> +		if (devargs->type != RTE_DEVTYPE_VIRTUAL)
>>> +			continue;
>>> +
>>> +		if (rte_eal_vdev_init(devargs->virt.drv_name,
>>
>> The situation now is:
>> rte_eal_init=>rte_eal_vdev_probe()=>rte_eal_vdev_init()=> driver->probe()
>>
>> Even though I had suggested this, my intention was to completely do away
>> with rte_*_[v]dev_init as it is misleading.
>>
>> rte_eal_init=>rte_eal_vdev_probe=>driver->probe()
>
> IMO, We don't need to remove rte_eal_vdev_init() as it is an
> application API that uses to create vdev driver instance.Moreover,
> change and removing that name will result in ABI breakage.
>
> grep -ri "rte_eal_vdev_init" app/
> app/test/test_cryptodev.c:				ret = rte_eal_vdev_init(
> app/test/test_cryptodev.c: TEST_ASSERT_SUCCESS(rte_eal_vdev_init(
> app/test/test_cryptodev.c: TEST_ASSERT_SUCCESS(rte_eal_vdev_init(
> app/test/test_cryptodev.c: TEST_ASSERT_SUCCESS(rte_eal_vdev_init(
> app/test/test_cryptodev.c: TEST_ASSERT_SUCCESS(rte_eal_vdev_init(
> app/test/test_cryptodev.c: int dev_id = rte_eal_vdev_init(
> app/test/test_cryptodev.c: ret = rte_eal_vdev_init(
> app/test/test_cryptodev_perf.c: ret = rte_eal_vdev_init(
> app/test/test_cryptodev_perf.c:	ret = rte_eal_vdev_init(
> app/test/test_cryptodev_perf.c:	ret = rte_eal_vdev_init(
> app/test/test_cryptodev_perf.c:	ret = rte_eal_vdev_init(
>

Got it.

Have you noticed patches from Ben which actually merges init and probe 
all together? [1]. It is for PCI right now (and that too would break 
ABIs, I am assuming).

[1] http://dpdk.org/dev/patchwork/patch/17206/

>
>>
>> should be the ideal order, IMO.
>> Apologies, I was not completely clear then.
>>
>>> +					devargs->args)) {
>>> +			RTE_LOG(ERR, EAL, "failed to initialize %s device\n",
>>> +					devargs->virt.drv_name);
>>> +			return -1;
>>> +		}
>>> +	}
>>> +
>>> +	return 0;
>>> +}
>>> diff --git a/lib/librte_eal/common/include/rte_dev.h b/lib/librte_eal/common/include/rte_dev.h
>>> index 8840380..146f505 100644
>>> --- a/lib/librte_eal/common/include/rte_dev.h
>>> +++ b/lib/librte_eal/common/include/rte_dev.h
>>> @@ -171,9 +171,9 @@ void rte_eal_driver_register(struct rte_driver *driver);
>>>  void rte_eal_driver_unregister(struct rte_driver *driver);
>>>
>>>  /**
>>> - * Initalize all the registered drivers in this process
>>> + * Probe all the registered vdev drivers in this process
>>>   */
>>> -int rte_eal_dev_init(void);
>>> +int rte_eal_vdev_probe(void);
>>>
>>>  /**
>>>   * Initialize a driver specified by name.
>>> diff --git a/lib/librte_eal/linuxapp/eal/eal.c b/lib/librte_eal/linuxapp/eal/eal.c
>>> index 16dd5b9..faf75cf 100644
>>> --- a/lib/librte_eal/linuxapp/eal/eal.c
>>> +++ b/lib/librte_eal/linuxapp/eal/eal.c
>>> @@ -884,8 +884,8 @@ rte_eal_init(int argc, char **argv)
>>>  	if (rte_eal_pci_probe())
>>>  		rte_panic("Cannot probe PCI\n");
>>>
>>> -	if (rte_eal_dev_init() < 0)
>>> -		rte_panic("Cannot init pmd devices\n");
>>> +	if (rte_eal_vdev_probe() < 0)
>>> +		rte_panic("Cannot probe vdev drivers\n");
>>>
>>>  	rte_eal_mcfg_complete();
>>>
>>> diff --git a/lib/librte_eal/linuxapp/eal/rte_eal_version.map b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
>>> index 83721ba..67fc95b 100644
>>> --- a/lib/librte_eal/linuxapp/eal/rte_eal_version.map
>>> +++ b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
>>> @@ -22,7 +22,7 @@ DPDK_2.0 {
>>>  	rte_dump_tailq;
>>>  	rte_eal_alarm_cancel;
>>>  	rte_eal_alarm_set;
>>> -	rte_eal_dev_init;
>>> +	rte_eal_vdev_probe;
>>>  	rte_eal_devargs_add;
>>>  	rte_eal_devargs_dump;
>>>  	rte_eal_devargs_type_count;
>>>
>>
>