Re: [PATCH v4 07/11] eal/pci: Add a function to remove the entry of devargs list

["Qiu, Michael" <michael.qiu-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>]

On 1/19/2015 6:42 PM, Tetsuya Mukawa wrote:
> The function removes the specified devargs entry from devargs_list.
> Also the patch adds sanity checking to rte_eal_devargs_add().
>
> v4:
> - Fix sanity check code
>
> Signed-off-by: Tetsuya Mukawa <mukawa-AlSX/UN32fvPDbFq/vQRIQ@public.gmane.org>
> ---
>  lib/librte_eal/common/eal_common_devargs.c  | 57 +++++++++++++++++++++++++++++
>  lib/librte_eal/common/include/rte_devargs.h | 18 +++++++++
>  2 files changed, 75 insertions(+)
>
> diff --git a/lib/librte_eal/common/eal_common_devargs.c b/lib/librte_eal/common/eal_common_devargs.c
> index 4c7d11a..a360a85 100644
> --- a/lib/librte_eal/common/eal_common_devargs.c
> +++ b/lib/librte_eal/common/eal_common_devargs.c
> @@ -44,6 +44,35 @@
>  struct rte_devargs_list devargs_list =
>  	TAILQ_HEAD_INITIALIZER(devargs_list);
>  
> +
> +/* find a entry specified by pci address or device name */
> +static struct rte_devargs *
> +rte_eal_devargs_find(enum rte_devtype devtype, void *args)
> +{
> +	struct rte_devargs *devargs;
> +
> +	if (args == NULL)
> +		return NULL;
> +
> +	TAILQ_FOREACH(devargs, &devargs_list, next) {
> +		switch (devtype) {
> +		case RTE_DEVTYPE_WHITELISTED_PCI:
> +		case RTE_DEVTYPE_BLACKLISTED_PCI:
> +			if (eal_compare_pci_addr(&devargs->pci.addr, args) == 0)
> +				goto found;
> +			break;
> +		case RTE_DEVTYPE_VIRTUAL:
> +			if (memcmp(&devargs->virtual.drv_name, args,
> +			    strlen((char *)args)) == 0)
> +				goto found;
> +			break;
> +		}
> +	}
> +	return NULL;
> +found:
> +	return devargs;
> +}
> +
>  /* store a whitelist parameter for later parsing */
>  int
>  rte_eal_devargs_add(enum rte_devtype devtype, const char *devargs_str)
> @@ -87,6 +116,12 @@ rte_eal_devargs_add(enum rte_devtype devtype, const char *devargs_str)
>  			free(devargs);
>  			return -1;
>  		}
> +		/* make sure there is no same entry */
> +		if (rte_eal_devargs_find(devtype, &devargs->pci.addr)) {
> +			RTE_LOG(ERR, EAL,
> +				"device already registered: <%s>\n", buf);
> +			return -1;
> +		}
>  		break;
>  	case RTE_DEVTYPE_VIRTUAL:
>  		/* save driver name */
> @@ -98,6 +133,12 @@ rte_eal_devargs_add(enum rte_devtype devtype, const char *devargs_str)
>  			free(devargs);
>  			return -1;
>  		}
> +		/* make sure there is no same entry */
> +		if (rte_eal_devargs_find(devtype, &devargs->virtual.drv_name)) {
> +			RTE_LOG(ERR, EAL,
> +				"device already registered: <%s>\n", buf);
> +			return -1;
> +		}
>  		break;
>  	}
>  
> @@ -105,6 +146,22 @@ rte_eal_devargs_add(enum rte_devtype devtype, const char *devargs_str)
>  	return 0;
>  }
>  
> +/* remove it from the devargs_list */
> +void
> +rte_eal_devargs_remove(enum rte_devtype devtype, void *args)
> +{
> +	struct rte_devargs *devargs;
> +
> +	if (args == NULL)
> +		return;
> +
> +	devargs = rte_eal_devargs_find(devtype, args);
> +	if (devargs == NULL)

If  devargs == NULL, means not found, does it reasonable to ignore? Some
error happens I think, at least you should print out some logs.

Thanks,
Michael
> +		return;
> +
> +	TAILQ_REMOVE(&devargs_list, devargs, next);
> +}
> +
>  /* count the number of devices of a specified type */
>  unsigned int
>  rte_eal_devargs_type_count(enum rte_devtype devtype)
> diff --git a/lib/librte_eal/common/include/rte_devargs.h b/lib/librte_eal/common/include/rte_devargs.h
> index 9f9c98f..1066efd 100644
> --- a/lib/librte_eal/common/include/rte_devargs.h
> +++ b/lib/librte_eal/common/include/rte_devargs.h
> @@ -123,6 +123,24 @@ extern struct rte_devargs_list devargs_list;
>  int rte_eal_devargs_add(enum rte_devtype devtype, const char *devargs_str);
>  
>  /**
> + * Remove a device from the user device list
> + *
> + * For PCI devices, the format of arguments string is "PCI_ADDR". It shouldn't
> + * involves parameters for the device. Example: "08:00.1".
> + *
> + * For virtual devices, the format of arguments string is "DRIVER_NAME*". It
> + * shouldn't involves parameters for the device. Example: "eth_ring". The
> + * validity of the driver name is not checked by this function, it is done
> + * when closing the drivers.
> + *
> + * @param devtype
> + *   The type of the device.
> + * @param name
> + *   The name of the device.
> + */
> +void rte_eal_devargs_remove(enum rte_devtype devtype, void *args);
> +
> +/**
>   * Count the number of user devices of a specified type
>   *
>   * @param devtype