Re: [PATCH] app/testpmd: app/testpmd: add device removal command

["Gaëtan Rivet" <gaetan.rivet@6wind.com>]

Hello Raslan,

On Wed, Aug 23, 2017 at 05:37:04PM +0300, Raslan Darawsheh wrote:
> Added hotplug in testpmd, to be able to test hotplug function
> in the PMD's.
> 
> Signed-off-by: Raslan Darawsheh <rasland@mellanox.com>
> ---
>  app/test-pmd/cmdline.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
>  app/test-pmd/testpmd.c | 18 ++++++++++++++++++
>  app/test-pmd/testpmd.h |  1 +
>  3 files changed, 63 insertions(+)
> 
> diff --git a/app/test-pmd/cmdline.c b/app/test-pmd/cmdline.c
> index cd8c358..b32a368 100644
> --- a/app/test-pmd/cmdline.c
> +++ b/app/test-pmd/cmdline.c
> @@ -716,6 +716,9 @@ static void cmd_help_long_parsed(void *parsed_result,
>  			"port config (port_id|all) l2-tunnel E-tag"
>  			" (enable|disable)\n"
>  			"    Enable/disable the E-tag support.\n\n"
> +
> +			" device remove (device)\n"
> +			"    Remove a device"

I think it should still be a part of the "port" command set (port
attach|detach|stop|close, etc).

This would probably be easier to understand for users.

>  		);
>  	}
>  
> @@ -1125,6 +1128,46 @@ cmdline_parse_inst_t cmd_operate_detach_port = {
>  	},
>  };
>  
> +/* *** Remove a specified device *** */
> +struct cmd_operate_device_remove_result {
> +	cmdline_fixed_string_t device;
> +	cmdline_fixed_string_t keyword;
> +	cmdline_fixed_string_t identifier;
> +};
> +
> +static void cmd_operate_device_remove_parsed(void *parsed_result,
> +				   __attribute__((unused)) struct cmdline *cl,
> +				   __attribute__((unused)) void *data)
> +{
> +	struct cmd_operate_device_remove_result *res = parsed_result;
> +	if (!strcmp(res->keyword, "remove"))
> +		device_remove((char *) res->identifier);
> +	else
> +		printf("Unknown parameter\n");
> +}
> +
> +cmdline_parse_token_string_t cmd_operate_device_remove_device =
> +	TOKEN_STRING_INITIALIZER(struct cmd_operate_device_remove_result,
> +			device, "device");
> +cmdline_parse_token_string_t cmd_operate_device_remove_keyword =
> +	TOKEN_STRING_INITIALIZER(struct cmd_operate_device_remove_result,
> +			keyword, "remove");
> +cmdline_parse_token_string_t cmd_operate_device_remove_identifier =
> +	TOKEN_STRING_INITIALIZER(struct cmd_operate_device_remove_result,
> +			identifier, NULL);
> +
> +cmdline_parse_inst_t cmd_operate_device_remove = {
> +	.f = cmd_operate_device_remove_parsed,
> +	.data = NULL,
> +	.help_str = "device remove <device>: (device)",
> +	.tokens = {
> +		(void *)&cmd_operate_device_remove_device,
> +		(void *)&cmd_operate_device_remove_keyword,
> +		(void *)&cmd_operate_device_remove_identifier,
> +		NULL,
> +	},
> +};
> +

Continuing on using the

port ...

format, then the port_id should allow to remove it instead of the device
identifier.
Using the device identifier will complexify your implementation.

>  /* *** configure speed for all ports *** */
>  struct cmd_config_speed_all {
>  	cmdline_fixed_string_t port;
> @@ -14276,6 +14319,7 @@ cmdline_parse_ctx_t main_ctx[] = {
>  	(cmdline_parse_inst_t *)&cmd_operate_specific_port,
>  	(cmdline_parse_inst_t *)&cmd_operate_attach_port,
>  	(cmdline_parse_inst_t *)&cmd_operate_detach_port,
> +	(cmdline_parse_inst_t *)&cmd_operate_device_remove,
>  	(cmdline_parse_inst_t *)&cmd_config_speed_all,
>  	(cmdline_parse_inst_t *)&cmd_config_speed_specific,
>  	(cmdline_parse_inst_t *)&cmd_config_rx_tx,
> diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c
> index 7d40139..a2e8526 100644
> --- a/app/test-pmd/testpmd.c
> +++ b/app/test-pmd/testpmd.c
> @@ -1742,6 +1742,24 @@ detach_port(uint8_t port_id)
>  }
>  
>  void
> +device_remove(char *device) {
> +	struct rte_devargs devargs;
> +
> +	if (device == NULL) {
> +		printf("Invalid parameters are specified\n");
> +		return;
> +	}

I don't think those checks are necessary. This function should not be
called with invalid parameters, and you will be the only one calling it.

> +
> +	rte_eal_devargs_parse(device, &devargs);

If you used a port_id, you would not have to parse the device string.
You could do something like this:

	struct rte_eth_dev *eth_dev;
	struct rte_bus *bus;

	eth_dev = &rte_eth_devices[port_id];
	bus = rte_bus_find_by_device(eth_dev->device);
> +
> +	if (rte_eal_hotplug_remove(devargs.bus->name, devargs.name)) {

  +	if (rte_eal_hotplug_remove(bus->name, eth_dev->device->name)) {

As a side note, I don't see why we need to use those names in the
function parameters.
We could simply use the rte_device handle available. This handle should
propose all necessary infos.
It might be a future API change.

> +		printf("Fail to remove device\n");
> +		return;
> +	}
> +	printf("Device removed successfully\n");
> +}
> +
> +void
>  pmd_test_exit(void)
>  {
>  	portid_t pt_id;
> diff --git a/app/test-pmd/testpmd.h b/app/test-pmd/testpmd.h
> index c9d7739..0780f55 100644
> --- a/app/test-pmd/testpmd.h
> +++ b/app/test-pmd/testpmd.h
> @@ -612,6 +612,7 @@ void stop_port(portid_t pid);
>  void close_port(portid_t pid);
>  void attach_port(char *identifier);
>  void detach_port(uint8_t port_id);
> +void device_remove(char *device);

void remove_port(uint8_t port_id);

>  int all_ports_stopped(void);
>  int port_is_started(portid_t port_id);
>  void pmd_test_exit(void);
> -- 
> 2.7.4
> 

-- 
Gaëtan Rivet
6WIND