[dpdk-dev] [PATCH v5 02/20] event/sw: add new software-only eventdev driver

[Van Haaren, Harry]

> From: Jerin Jacob [mailto:jerin.jacob at caviumnetworks.com]
> Sent: Saturday, March 25, 2017 6:24 AM
> To: Van Haaren, Harry <harry.van.haaren at intel.com>
> Cc: dev at dpdk.org; Richardson, Bruce <bruce.richardson at intel.com>
> Subject: Re: [PATCH v5 02/20] event/sw: add new software-only eventdev driver
> 
> On Fri, Mar 24, 2017 at 04:52:57PM +0000, Harry van Haaren wrote:
> > From: Bruce Richardson <bruce.richardson at intel.com>
> >
> > This adds the minimal changes to allow a SW eventdev implementation to
> > be compiled, linked and created at run time. The eventdev does nothing,
> > but can be created via vdev on commandline, e.g.
> >
> >   sudo ./x86_64-native-linuxapp-gcc/app/test --vdev=event_sw0
> >   ...
> >   PMD: Creating eventdev sw device event_sw0, numa_node=0, sched_quanta=128
> >   RTE>>
> >
> > Signed-off-by: Bruce Richardson <bruce.richardson at intel.com>
> > Signed-off-by: Harry van Haaren <harry.van.haaren at intel.com>
> > ---
> >  config/common_base                            |   6 +
> >  drivers/event/Makefile                        |   1 +
> >  drivers/event/sw/Makefile                     |  66 ++++++++++
> >  drivers/event/sw/rte_pmd_evdev_sw_version.map |   3 +
> >  drivers/event/sw/sw_evdev.c                   | 177 ++++++++++++++++++++++++++
> 
> [snip]

<snip>

> > +
> > +static int
> > +assign_numa_node(const char *key __rte_unused, const char *value, void *opaque)
> > +{
> > +	int *socket_id = opaque;
> > +	*socket_id = atoi(value);
> > +	if (*socket_id > RTE_MAX_NUMA_NODES)
> 
> Shouldn't be ">= RTE_MAX_NUMA_NODES" check, as numa_id is from 0 to
> RTE_MAX_NUMA_NODES - 1

Yes - thanks fixed, also fixed for quanta and credits below.


> > +		return -1;
> > +	return 0;
> > +}
> > +
> > +static int
> > +set_sched_quanta(const char *key __rte_unused, const char *value, void *opaque)
> > +{
> > +	int *quanta = opaque;
> > +	*quanta = atoi(value);
> > +	if (*quanta < 0 || *quanta > 4096)
> 
> Is quanta == 4096 valid? or It is only from 0 to 4095?
> 
> I think, it is nice to set max value as #define value in sw_evdev.h
> 
> > +		return -1;
> > +	return 0;
> > +}
> > +
> > +static int
> > +set_credit_quanta(const char *key __rte_unused, const char *value, void *opaque)
> > +{
> > +	int *credit = opaque;
> > +	*credit = atoi(value);
> > +	if (*credit < 0 || *credit > 128)
> 
> Same as above comment.
> 
> > +		return -1;
> > +	return 0;
> > +}
> > +
> > +static int
> > +sw_probe(const char *name, const char *params)
> > +{
> > +	static const struct rte_eventdev_ops evdev_sw_ops = {
> > +	};
> > +
> > +	static const char *const args[] = {
> > +		NUMA_NODE_ARG,
> > +		SCHED_QUANTA_ARG,
> > +		CREDIT_QUANTA_ARG,
> > +		NULL
> > +	};
> > +	struct rte_eventdev *dev;
> > +	struct sw_evdev *sw;
> > +	int socket_id = rte_socket_id();
> > +	int sched_quanta  = SW_DEFAULT_SCHED_QUANTA;
> > +	int credit_quanta = SW_DEFAULT_CREDIT_QUANTA;
> > +
> > +	if (params != NULL && params[0] != '\0') {
> > +		struct rte_kvargs *kvlist = rte_kvargs_parse(params, args);
> > +
> > +		if (!kvlist) {
> > +			SW_LOG_INFO(
> > +				"Ignoring unsupported parameters when creating device '%s'\n",
> > +				name);
> > +		} else {
> > +			int ret = rte_kvargs_process(kvlist, NUMA_NODE_ARG,
> > +					assign_numa_node, &socket_id);
> > +			if (ret != 0) {
> > +				SW_LOG_ERR(
> > +					"%s: Error parsing numa node parameter",
> > +					name);
> > +				rte_kvargs_free(kvlist);
> > +				return ret;
> > +			}
> > +
> > +			ret = rte_kvargs_process(kvlist, SCHED_QUANTA_ARG,
> > +					set_sched_quanta, &sched_quanta);
> > +			if (ret != 0) {
> > +				SW_LOG_ERR(
> > +					"%s: Error parsing sched quanta parameter",
> > +					name);
> > +				rte_kvargs_free(kvlist);
> > +				return ret;
> > +			}
> > +
> > +			ret = rte_kvargs_process(kvlist, CREDIT_QUANTA_ARG,
> > +					set_credit_quanta, &credit_quanta);
> > +			if (ret != 0) {
> > +				SW_LOG_ERR(
> > +					"%s: Error parsing credit quanta parameter",
> > +					name);
> > +				rte_kvargs_free(kvlist);
> > +				return ret;
> > +			}
> > +
> > +			rte_kvargs_free(kvlist);
> > +		}
> > +	}
> > +
> > +	SW_LOG_INFO(
> 
> An extra line here may be not required here.

Checkpatch warns on "long line" if this extra whitespace is not present.


> > +			"Creating eventdev sw device %s, numa_node=%d, sched_quanta=%d,
> credit_quanta=%d\n",
> > +			name, socket_id, sched_quanta, credit_quanta);
> > +
> > +	dev = rte_event_pmd_vdev_init(name,
> > +			sizeof(struct sw_evdev), socket_id);
> > +	if (dev == NULL) {
> > +		SW_LOG_ERR("eventdev vdev init() failed");
> > +		return -EFAULT;
> > +	}
> > +	dev->dev_ops = &evdev_sw_ops;
> > +
> > +	sw = dev->data->dev_private;
> > +	sw->data = dev->data;
> > +
> > +	/* copy values passed from vdev command line to instance */
> > +	sw->credit_update_quanta = credit_quanta;
> > +	sw->sched_quanta = sched_quanta;
> > +
> > +	return 0;
> > +}
> > +
> > +static int
> > +sw_remove(const char *name)
> > +{
> > +	if (name == NULL)
> > +		return -EINVAL;
> > +
> > +	SW_LOG_INFO("Closing eventdev sw device %s\n", name);
> > +
> > +	return rte_event_pmd_vdev_uninit(name);
> > +}
> > +
> > +static struct rte_vdev_driver evdev_sw_pmd_drv = {
> > +	.probe = sw_probe,
> > +	.remove = sw_remove
> > +};
> > +
> > +RTE_PMD_REGISTER_VDEV(EVENTDEV_NAME_SW_PMD, evdev_sw_pmd_drv);
> > +RTE_PMD_REGISTER_PARAM_STRING(event_sw, NUMA_NODE_ARG "=<int> "
> > +		SCHED_QUANTA_ARG "=<int>" CREDIT_QUANTA_ARG "=<int>");
> 
> With suggested changes,
> 
> Acked-by: Jerin Jacob <jerin.jacob at caviumnetworks.com>

Thanks for review!