[dpdk-dev] [PATCH v8 6/9] ethdev: add common devargs parser

[Doherty, Declan]

On 26/04/2018 1:03 PM, Ananyev, Konstantin wrote:
> 
> 
>> -----Original Message-----
>> From: Doherty, Declan
>> Sent: Thursday, April 26, 2018 11:41 AM
>> To: dev at dpdk.org
>> Cc: Adrien Mazarguil <adrien.mazarguil at 6wind.com>; Yigit, Ferruh <ferruh.yigit at intel.com>; Thomas Monjalon <thomas at monjalon.net>;
>> Shahaf Shuler <shahafs at mellanox.com>; Ananyev, Konstantin <konstantin.ananyev at intel.com>; Horton, Remy <remy.horton at intel.com>;
>> Doherty, Declan <declan.doherty at intel.com>
>> Subject: [dpdk-dev][PATCH v8 6/9] ethdev: add common devargs parser
>>
>> From: Remy Horton <remy.horton at intel.com>
>>
>> Introduces a new structure, rte_eth_devargs, to support generic
>> ethdev arguments common across NET PMDs, with a new API
>> rte_eth_devargs_parse API to support PMD parsing these arguments. The
>> patch add support for a representor argument  passed with passed with
>> the EAL -w option. The representor parameter allows the user to specify
>> which representor ports to initialise on a device.
>>
>> The argument supports passing a single representor port, a list of
>> port values or a range of port values.
>>
>> -w BDF,representor=1  # create representor port 1 on pci device BDF
>> -w BDF,representor=[1,2,5,6,10] # create representor ports in list
>> -w BDF,representor=[0-31] # create representor ports in range
>>
>> Signed-off-by: Remy Horton <remy.horton at intel.com>
>> Signed-off-by: Declan Doherty <declan.doherty at intel.com>
>> ---
>>   doc/guides/prog_guide/poll_mode_drv.rst |  19 ++++
>>   lib/Makefile                            |   1 +
>>   lib/librte_ether/rte_ethdev.c           | 182 ++++++++++++++++++++++++++++++++
>>   lib/librte_ether/rte_ethdev_driver.h    |  30 ++++++
>>   lib/librte_ether/rte_ethdev_version.map |   1 +
>>   5 files changed, 233 insertions(+)
>>
>> diff --git a/doc/guides/prog_guide/poll_mode_drv.rst b/doc/guides/prog_guide/poll_mode_drv.rst
>> index e5d01874e..09a93baec 100644
>> --- a/doc/guides/prog_guide/poll_mode_drv.rst
>> +++ b/doc/guides/prog_guide/poll_mode_drv.rst
>> @@ -345,6 +345,25 @@ Ethernet Device API
>>
>>   The Ethernet device API exported by the Ethernet PMDs is described in the *DPDK API Reference*.
>>
>> +Ethernet Device Standard Device Arguments
>> +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> +
>> +Standard Ethernet device arguments allow for a set of commonly used arguments/
>> +parameters which are applicable to all Ethernet devices to be available to for
>> +specification of specific device and for passing common configuration
>> +parameters to those ports.
>> +
>> +* ``representor`` for a device which supports the creation of representor ports
>> +  this argument allows user to specify which switch ports to enable port
>> +  representors for.::
>> +
>> +   -w BDBF,representor=0
>> +   -w BDBF,representor=[0,4,6,9]
>> +   -w BDBF,representor=[0-31]
>> +
>> +Note: PMDs are not required to support the standard device arguments and users
>> +should consult the relevant PMD documentation to see support devargs.
>> +
>>   Extended Statistics API
>>   ~~~~~~~~~~~~~~~~~~~~~~~
>>
>> diff --git a/lib/Makefile b/lib/Makefile
>> index 965be6c8d..536775e59 100644
>> --- a/lib/Makefile
>> +++ b/lib/Makefile
>> @@ -21,6 +21,7 @@ DEPDIRS-librte_cmdline := librte_eal
>>   DIRS-$(CONFIG_RTE_LIBRTE_ETHER) += librte_ether
>>   DEPDIRS-librte_ether := librte_net librte_eal librte_mempool librte_ring
>>   DEPDIRS-librte_ether += librte_mbuf
>> +DEPDIRS-librte_ether += librte_kvargs
>>   DIRS-$(CONFIG_RTE_LIBRTE_BBDEV) += librte_bbdev
>>   DEPDIRS-librte_bbdev := librte_eal librte_mempool librte_mbuf
>>   DIRS-$(CONFIG_RTE_LIBRTE_CRYPTODEV) += librte_cryptodev
>> diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
>> index 621f8af7f..cb85d8bb7 100644
>> --- a/lib/librte_ether/rte_ethdev.c
>> +++ b/lib/librte_ether/rte_ethdev.c
>> @@ -34,6 +34,7 @@
>>   #include <rte_errno.h>
>>   #include <rte_spinlock.h>
>>   #include <rte_string_fns.h>
>> ++#include <rte_kvargs.h>
>>
>>   #include "rte_ether.h"
>>   #include "rte_ethdev.h"
>> @@ -4101,6 +4102,187 @@ rte_eth_dev_pool_ops_supported(uint16_t port_id, const char *pool)
>>   	return (*dev->dev_ops->pool_ops_supported)(dev, pool);
>>   }
>>
>> +typedef int (*rte_eth_devargs_callback_t)(char *str, void *data);
>> +
>> +static int
>> +rte_eth_devargs_tokenise(struct rte_kvargs *arglist, const char *str_in)
>> +{
> 
> I still think that if you'd like to extend rte_kvarrgs to be able to parse something like: "key=[val1,val2,...,valn]",
> you have to make it generic kvargs ability and put it into librte_kvargs, not try to introduce your own new parser here.
> Imagine that in addition to your 'port=[val1,val2, ..valn]' devargs string would contain some extra (let say device specific)
> parameters.
> What would happen, when PMD will try to use rte_kvargs_parse() on such string?
> My understanding - it would fail, correct?
> 
> As an alternative - as I remember rte_kvargs allows you to have multiple identical key, i.e: "key=val1,key=val2,...,key=valn".
> Why not to use that way, if you don't want to introduce extra code in rte_kvargs?
> 

Hey Konstantin, the rationale for keeping this independent from 
librte_kvargs was that it is likely that the implementation of parsing 
devarfs will change in the next release due the proposed rework on the 
whole devargs infrastructure. I hadn't considered the potential issue 
with rte_kvargs_parse() on string using the proposed syntax here. I'll 
send a patch for alignment with librte_kvargs for the next release 
candidate.

>> +	int state;
>> +	struct rte_kvargs_pair *pair;
>> +	char *letter;
>> +
>> +	arglist->str = strdup(str_in);
>> +	if (arglist->str == NULL)
>> +		return -ENOMEM;
>> +
>> +	letter = arglist->str;
>> +	state = 0;
>> +	arglist->count = 0;
>> +	pair = &arglist->pairs[0];
>> +	while (1) {
>> +		switch (state) {
>> +		case 0: /* Initial */
>> +			if (*letter == '=')
>> +				return -EINVAL;
>> +			else if (*letter == '\0')
>> +				return 0;
>> +
>> +			state = 1;
>> +			pair->key = letter;
>> +			/* fall-thru */
>> +
>> +		case 1: /* Parsing key */
>> +			if (*letter == '=') {
>> +				*letter = '\0';
>> +				pair->value = letter + 1;
>> +				state = 2;
>> +			} else if (*letter == ',' || *letter == '\0')
>> +				return -EINVAL;
>> +			break;
>> +
>> +
>> +		case 2: /* Parsing value */
>> +			if (*letter == '[')
>> +				state = 3;
>> +			else if (*letter == ',') {
>> +				*letter = '\0';
>> +				arglist->count++;
>> +				pair = &arglist->pairs[arglist->count];
>> +				state = 0;
>> +			} else if (*letter == '\0') {
>> +				letter--;
>> +				arglist->count++;
>> +				pair = &arglist->pairs[arglist->count];
>> +				state = 0;
>> +			}
>> +			break;
>> +
>> +		case 3: /* Parsing list */
>> +			if (*letter == ']')
>> +				state = 2;
>> +			else if (*letter == '\0')
>> +				return -EINVAL;
>> +			break;
>> +		}
>> +		letter++;
>> +	}
>> +}
>> +
>> +static int
>> +rte_eth_devargs_parse_list(char *str, rte_eth_devargs_callback_t callback,
>> +	void *data)
>> +{
>> +	char *str_start;
>> +	int state;
>> +	int result;
>> +
>> +	if (*str != '[')
>> +		/* Single element, not a list */
>> +		return callback(str, data);
>> +
>> +	/* Sanity check, then strip the brackets */
>> +	str_start = &str[strlen(str) - 1];
>> +	if (*str_start != ']') {
>> +		RTE_LOG(ERR, EAL, "(%s): List does not end with ']'", str);
>> +		return -EINVAL;
>> +	}
>> +	str++;
>> +	*str_start = '\0';
>> +
>> +	/* Process list elements */
>> +	state = 0;
>> +	while (1) {
>> +		if (state == 0) {
>> +			if (*str == '\0')
>> +				break;
>> +			if (*str != ',') {
>> +				str_start = str;
>> +				state = 1;
>> +			}
>> +		} else if (state == 1) {
>> +			if (*str == ',' || *str == '\0') {
>> +				if (str > str_start) {
>> +					/* Non-empty string fragment */
>> +					*str = '\0';
>> +					result = callback(str_start, data);
>> +					if (result < 0)
>> +						return result;
>> +				}
>> +				state = 0;
>> +			}
>> +		}
>> +		str++;
>> +	}
>> +	return 0;
>> +}
>> +
>> +static int
>> +rte_eth_devargs_process_range(char *str, uint16_t *list, uint16_t *len_list,
>> +	const uint16_t max_list)
>> +{
>> +	uint16_t lo, hi, val;
>> +	int result;
>> +
>> +	result = sscanf(str, "%hu-%hu", &lo, &hi);
>> +	if (result == 1) {
>> +		if (*len_list >= max_list)
>> +			return -ENOMEM;
>> +		list[(*len_list)++] = lo;
>> +	} else if (result == 2) {
>> +		if (lo >= hi || lo > RTE_MAX_ETHPORTS || hi > RTE_MAX_ETHPORTS)
> 
> lo > RTE_MAX_ETHPORTS is redundant here.
> 
>> +			return -EINVAL;
>> +		for (val = lo; val <= hi; val++) {
>> +			if (*len_list >= max_list)
>> +				return -ENOMEM;
>> +			list[(*len_list)++] = val;
>> +		}
>> +	} else
>> +		return -EINVAL;
>> +	return 0;
>> +}
>> +
>> +
>> +static int
>> +rte_eth_devargs_parse_representor_ports(char *str, void *data)
>> +{
>> +	struct rte_eth_devargs *eth_da = data;
>> +
>> +	return rte_eth_devargs_process_range(str, eth_da->representor_ports,
>> +		&eth_da->nb_representor_ports, RTE_MAX_ETHPORTS);
>> +}
>> +
>> +int __rte_experimental
>> +rte_eth_devargs_parse(const char *dargs, struct rte_eth_devargs *eth_da)
>> +{
>> +	struct rte_kvargs args;
>> +	struct rte_kvargs_pair *pair;
>> +	unsigned int i;
>> +	int result = 0;
>> +
>> +	memset(eth_da, 0, sizeof(*eth_da));
>> +
>> +	result = rte_eth_devargs_tokenise(&args, dargs);
>> +	if (result < 0)
>> +		goto parse_cleanup;
>> +
>> +	for (i = 0; i < args.count; i++) {
>> +		pair = &args.pairs[i];
>> +		if (strcmp("representor", pair->key) == 0) {
>> +			result = rte_eth_devargs_parse_list(pair->value,
>> +				rte_eth_devargs_parse_representor_ports,
>> +				eth_da);
>> +			if (result < 0)
>> +				goto parse_cleanup;
>> +		}
>> +	}
>> +
>> +parse_cleanup:
>> +	if (args.str)
>> +		free(args.str);
>> +
>> +	return result;
>> +}
>> +
>>   RTE_INIT(ethdev_init_log);
>>   static void
>>   ethdev_init_log(void)
>> diff --git a/lib/librte_ether/rte_ethdev_driver.h b/lib/librte_ether/rte_ethdev_driver.h
>> index 8c61ab2f4..492da754a 100644
>> --- a/lib/librte_ether/rte_ethdev_driver.h
>> +++ b/lib/librte_ether/rte_ethdev_driver.h
>> @@ -189,6 +189,36 @@ rte_eth_linkstatus_get(const struct rte_eth_dev *dev,
>>   }
>>
>>
>> +/** Generic Ethernet device arguments  */
>> +struct rte_eth_devargs {
>> +	uint16_t ports[RTE_MAX_ETHPORTS];
>> +	/** port/s number to enable on a multi-port single function */
>> +	uint16_t nb_ports;
>> +	/** number of ports in ports field */
>> +	uint16_t representor_ports[RTE_MAX_ETHPORTS];
>> +	/** representor port/s identifier to enable on device */
>> +	uint16_t nb_representor_ports;
>> +	/** number of ports in representor port field */
>> +};
>> +
>> +/**
>> + * @warning
>> + * @b EXPERIMENTAL: this API may change without prior notice.
>> + *
>> + * PMD helper function to parse ethdev arguments
>> + *
>> + * @param devargs
>> + *  device arguments
>> + * @param eth_devargs
>> + *  parsed ethdev specific arguments.
>> + *
>> + * @return
>> + *   Negative errno value on error, 0 on success.
>> + */
>> +int __rte_experimental
>> +rte_eth_devargs_parse(const char *dargs, struct rte_eth_devargs *eth_devargs);
>> +
>> +
>>   typedef int (*ethdev_init_t)(struct rte_eth_dev *ethdev, void *init_params);
>>   typedef int (*ethdev_bus_specific_init)(struct rte_eth_dev *ethdev,
>>   	void *bus_specific_init_params);
>> diff --git a/lib/librte_ether/rte_ethdev_version.map b/lib/librte_ether/rte_ethdev_version.map
>> index c4380aa31..41c3d2699 100644
>> --- a/lib/librte_ether/rte_ethdev_version.map
>> +++ b/lib/librte_ether/rte_ethdev_version.map
>> @@ -206,6 +206,7 @@ DPDK_18.02 {
>>   EXPERIMENTAL {
>>   	global:
>>
>> +	rte_eth_devargs_parse;
>>   	rte_eth_dev_count_avail;
>>   	rte_eth_dev_count_total;
>>   	rte_eth_dev_create;
>> --
>> 2.14.3
>