[dpdk-dev] [PATCH v11 1/1] net/af_xdp: introduce AF XDP PMD driver

[Ferruh Yigit]

On 4/4/2019 9:51 AM, Xiaolong Ye wrote:
> Add a new PMD driver for AF_XDP which is a proposed faster version of
> AF_PACKET interface in Linux. More info about AF_XDP, please refer to [1]
> [2].
> 
> This is the vanilla version PMD which just uses a raw buffer registered as
> the umem.
> 
> [1] https://fosdem.org/2018/schedule/event/af_xdp/
> [2] https://lwn.net/Articles/745934/
> 
> Signed-off-by: Xiaolong Ye <xiaolong.ye at intel.com>

<...>

> diff --git a/drivers/net/af_xdp/meson.build b/drivers/net/af_xdp/meson.build
> new file mode 100644
> index 000000000..840c93728
> --- /dev/null
> +++ b/drivers/net/af_xdp/meson.build
> @@ -0,0 +1,19 @@
> +# SPDX-License-Identifier: BSD-3-Clause
> +# Copyright(c) 2019 Intel Corporation
> +
> +if host_machine.system() == 'linux'
> +	bpf_dep = dependency('libbpf', required: false)
> +	if bpf_dep.found()
> +		build = true
> +	else
> +		bpf_dep = cc.find_library('bpf', required: false)
> +		if bpf_dep.found() and cc.has_header('bpf/xsk.h', dependencies: bpf_dep) and cc.has_header('linux/if_xdp.h')
> +			build = true
> +			pkgconfig_extra_libs += '-lbpf'
> +		else
> +			build = false
> +		endif
> +	endif
> +	ext_deps += bpf_dep
> +endif
> +sources = files('rte_eth_af_xdp.c')

if system is not 'linux', by default build will be 'true', right, so will it try
to build the driver in that case?
What about setting "build = false" before the linux check, so won't need to set
it false again in the if block, only set it true if dependencies found?
And can 'ext_deps' go out of if block?