How to gdb example/helloworld?

[QinLongFei]

Hi, f-stack team,

I'm learning f-stack and want to gdb helloworld example. But I found I cannot gdb DPDK function. For example I cannot next in rte_eal_init. F-Stack function is OK.

I have enabled DPDK debug mode by executing export EXTRA_CFLAGS='-O0 -g' and enable F-Stack debug mode in lib/Makefile.

Need your help!!!

[jfb8856606]

export EXTRA_CFLAGS='-O0 -g' and recompile DPDK/F-Fstack lib and helloworld example is work correct for me.
Wehter you exec make install instead export FF_PATH=/data/f-stack and export FF_DPDK=/data/f-stack/dpdk/x86_64-native-linuxapp-gcc, or whether to recompile DPDK/F-Stack lib and helloworld completely.

[QinLongFei]

Thanks.

I write a shell script to run. I use export FF_PATH/FF_DPDK instead make install.

#!/bin/bash

cd dpdk
make config T=x86_64-native-linuxapp-gcc EXTRA_CFLAGS='-O0 -g' && make
cd ..

echo 1024 > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
mount -t hugetlbfs nodev /mnt/huge
modprobe uio
insmod /root/f-stack/dpdk/x86_64-native-linuxapp-gcc/kmod/igb_uio.ko
insmod /root/f-stack/dpdk/x86_64-native-linuxapp-gcc/kmod/rte_kni.ko carrier=on
ifconfig ens37 down
python /root/f-stack/dpdk/usertools/dpdk-devbind.py --bind=igb_uio ens37

export FF_PATH=/root/f-stack
export FF_DPDK=/root/f-stack/dpdk/x86_64-native-linuxapp-gcc
cd lib
make clean
make -j8

[QinLongFei]

Before run this script, I always reboot my centOS.

[jfb8856606]

You may try use export FF_DPDK=/root/f-stack/dpdk/build instead export FF_DPDK=/root/f-stack/dpdk/x86_64-native-linuxapp-gcc

[jfb8856606]

or

rm -rf /root/f-stack/dpdk/x86_64-native-linuxapp-gcc
ln -s /root/f-stack/dpdk/build /root/f-stack/dpdk/x86_64-native-linuxapp-gcc

[QinLongFei]

I try use export FF_DPDK=/root/f-stack/dpdk/build. But I still cannot gdb rte_eal_init.

#!/bin/bash

cd dpdk
make config T=x86_64-native-linuxapp-gcc EXTRA_CFLAGS='-O0 -g' && make
cd ..

echo 1024 > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
mount -t hugetlbfs nodev /mnt/huge
modprobe uio
insmod /root/f-stack/dpdk/x86_64-native-linuxapp-gcc/kmod/igb_uio.ko
insmod /root/f-stack/dpdk/x86_64-native-linuxapp-gcc/kmod/rte_kni.ko carrier=on
ifconfig ens37 down
python /root/f-stack/dpdk/usertools/dpdk-devbind.py --bind=igb_uio ens37

export FF_PATH=/root/f-stack
export FF_DPDK=/root/f-stack/dpdk/build
cd lib
make clean
make -j8

[QinLongFei]

@jfb8856606 , Can you gdb dpdk function?(for example, rte_eal_init)

[jfb8856606]

I try make config T=x86_64-native-linuxapp-gcc EXTRA_CFLAGS='-O0 -g' && make and it may not work.
Usually， I run

export EXTRA_CFLAGS='-O0 -g'
cd /root/f-stack/dpdk/x86_64-native-linuxapp-gcc  # if there is't the dir, shoud run cd /root/f-stack/dpdk/usertools/;python ./dpdk-setup.sh and select 15
make clean
make

and need reuse export FF_DPDK=/root/f-stack/dpdk/x86_64-native-linuxapp-gcc

[QinLongFei]

@jfb8856606 ,

I have tried your way but it still cannot work.

I think maybe it caused by "LIBS+= -L${FF_DPDK}/lib -Wl,--whole-archive,-ldpdk,--no-whole-archive" in example/Makefile

I don't know why use "whole-archive" .This is normally used to turn an archive file into a shared library, forcing every object to be included in the resulting shared library.

I think the reason why I cannot gdb dpdk function is dpdk is linked as shared library. Right?

[QinLongFei]

My question is not helloworld cannot work but I cannot gdb helloworld.

[QinLongFei]

Do you try gdb the helloworld and set a breakpoint in rte_eal_init? What will happen when you input "next"? Following is my result.

[jfb8856606]

Sure, i can do it. The helloworld not recompile in your script, you will recompile helloworld manual?

[QinLongFei]

Yes, I recompile helleworld manually every time.

[QinLongFei]

Update script to compile helloworld each time.

#!/bin/bash

#DPDK_PATH=/root/dpdk-stable-18.11.6

DPDK_PATH=/home/fqin/f-stack/dpdk
FSTACK_PATH=/home/fqin/f-stack
cd $DPDK_PATH
make config T=x86_64-native-linuxapp-gcc EXTRA_CFLAGS='-O0 -g -Wno-address-of-packed-member' && make -j8
cd $FSTACK_PATH

echo 1024 > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
mount -t hugetlbfs nodev /mnt/huge
modprobe uio
insmod $DPDK_PATH/build/kmod/igb_uio.ko
insmod $DPDK_PATH/build/kmod/rte_kni.ko carrier=on
#ifconfig ens33 down
#python $DPDK_PATH/usertools/dpdk-devbind.py --bind=igb_uio ens33

export FF_PATH=$FSTACK_PATH
export FF_DPDK=$DPDK_PATH/build

cd $FSTACK_PATH/lib
make clean
make -j8

cd $FSTACK_PATH/example
make
cd $FSTACK_PATH

[jfb8856606]

Run cat $DPDK_PATH/build/build/lib/librte_eal/linuxapp/eal/.eal.o.cmd or cat $DPDK_PATH/x86_64-native-linuxapp-gcc/build/lib/librte_eal/linuxapp/eal/.eal.o.cmd

And check -O0 -g whether be added. If not, it's means export EXTRA_CFLAGS='-O0 -g' not set correctly.