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dpdk 编译helloworld报错
前言
环境与目录
[root@bogon helloworld]# pwd
/home/kira/dpdk-21.08/examples/helloworld
出错位置
[kira@bogon helloworld]$ make
Makefile:14: *** "no installation of DPDK found"。 停止。
[kira@bogon helloworld]$
分析
Makefile 14行报错，先看看Makefile文件
vi Makefile
1 # SPDX-License-Identifier: BSD-3-Clause
2 # Copyright(c) 2010-2014 Intel Corporation
3
4 # binary name
5 APP = helloworld
6
7 # all source are stored in SRCS-y
8 SRCS-y := main.c
9
10 PKGCONF ?= pkg-config
11
12 # Build using pkg-config variables if possible
13 ifneq ($(shell $(PKGCONF) --exists libdpdk && echo 0),0)
14 $(error "no installation of DPDK found")
15 endif
16
是在shell执行 pkg-config --exists libdpdk的时候报错，shell返回为空
手动执行下试试，确实是这样
[root@bogon helloworld]# pkg-config --exists libdpdk
[root@bogon helloworld]#
看一下pkg-config是个什么东东，参考 博客园 pkg-config 详解 啊，原来是帮忙看编译时候一堆库之类的存放位置的，命令行敲一下有帮助 (写笔记时候libdpdk已经正常，拿dpdk来试一下)
[kira@bogon ~]$ pkg-config
Must specify package names on the command line
[kira@bogon ~]$ pkg-config dpdk --libs
Package dpdk was not found in the pkg-config search path.
Perhaps you should add the directory containing `dpdk.pc'
to the PKG_CONFIG_PATH environment variable
No package 'dpdk' found
[kira@bogon ~]$
问题定位
通过上面的流程，知道了是 pkg-config 找不到 libdpdk， 参考 官网部署文档，英文 的说明，是有 libdpdk.pc 这个文件的 官网文档节选：
3.2.4. Building Applications Using Installed DPDK When installed system-wide, DPDK provides a pkg-config file libdpdk.pc for applications to query as part of their build. It’s recommended that the pkg-config file be used, rather than hard-coding the parameters (cflags/ldflags) for DPDK into the application build process.
An example of how to query and use the pkg-config file can be found in the Makefile of each of the example applications included with DPDK. A simplified example snippet is shown below, where the target binary name has been stored in the variable (SRCS-y).
那么，定位下这个文件，其实在系统目录里已经有了，是 pkg-config 没有找到这个文件
[kira@bogon helloworld]$ sudo find / -name "libdpdk.pc"
[sudo] kira 的密码：
/usr/local/lib64/pkgconfig/libdpdk.pc
/home/kira/dpdk-21.08/build/meson-private/libdpdk.pc
/home/kira/dpdk-21.08/clean/meson-private/libdpdk.pc
[kira@bogon helloworld]$
参考 pkg-config libdpdk --libs这个命令的提示，我们需要把这个文件的搜索路径放到 PKG_CONFIG_PATH这个环境变量里来，试一下
[kira@bogon helloworld]$ export PKG_CONFIG_PATH="/usr/local/lib64/pkgconfig/"
[kira@bogon helloworld]$ pkg-config libdpdk --libs
-Wl,--as-needed -L/usr/local/lib64 -lrte_node -lrte_graph -lrte_bpf -lrte_flow_classify -lrte_pipeline -lrte_table -lrte_port -lrte_fib -lrte_ipsec -lrte_vhost -lrte_stack -lrte_security -lrte_sched -lrte_reorder -lrte_rib -lrte_regexdev -lrte_rawdev -lrte_pdump -lrte_power -lrte_member -lrte_lpm -lrte_latencystats -lrte_kni -lrte_jobstats -lrte_ip_frag -lrte_gso -lrte_gro -lrte_eventdev -lrte_efd -lrte_distributor -lrte_cryptodev -lrte_compressdev -lrte_cfgfile -lrte_bitratestats -lrte_bbdev -lrte_acl -lrte_timer -lrte_hash -lrte_metrics -lrte_cmdline -lrte_pci -lrte_ethdev -lrte_meter -lrte_net -lrte_mbuf -lrte_mempool -lrte_rcu -lrte_ring -lrte_eal -lrte_telemetry -lrte_kvargs
好了，看起来 pkg-config的问题正常了，再重新试一下编译
[kira@bogon helloworld]$ su
密码：
[root@bogon helloworld]# make
cc -O3 -include rte_config.h -march=native -I/usr/local/include -DALLOW_EXPERIMENTAL_API main.c -o build/helloworld-shared -Wl,--as-needed -L/usr/local/lib64 -lrte_node -lrte_graph -lrte_bpf -lrte_flow_classify -lrte_pipeline -lrte_table -lrte_port -lrte_fib -lrte_ipsec -lrte_vhost -lrte_stack -lrte_security -lrte_sched -lrte_reorder -lrte_rib -lrte_regexdev -lrte_rawdev -lrte_pdump -lrte_power -lrte_member -lrte_lpm -lrte_latencystats -lrte_kni -lrte_jobstats -lrte_ip_frag -lrte_gso -lrte_gro -lrte_eventdev -lrte_efd -lrte_distributor -lrte_cryptodev -lrte_compressdev -lrte_cfgfile -lrte_bitratestats -lrte_bbdev -lrte_acl -lrte_timer -lrte_hash -lrte_metrics -lrte_cmdline -lrte_pci -lrte_ethdev -lrte_meter -lrte_net -lrte_mbuf -lrte_mempool -lrte_rcu -lrte_ring -lrte_eal -lrte_telemetry -lrte_kvargs
ln -sf helloworld-shared build/helloworld
[root@bogon helloworld]#
大功告成
撒花
完结
