vtune准备——开启linux内核调试信息

解决报错：cannot locate debugging information for file

内核需要三部分调试信息

1 打开内核module解析

检查/proc/sys/kernel/kptr_restrict

# cat /proc/sys/kernel/kptr_restrict
0

• If the kptr_restrict value is 0, kernel addresses are provided without limitations (recommended).
• If the kptr_restict value is 1, addresses are provided if the current user has a CAP_SYSLOG capability.
• If the kptr_restrict value is 2, the kernel addresses are hidden regardless of privileges the current user has.

2 安装内核debug信息

查看包名

echo "kernel-debuginfo-common-x86_64-`uname -r`.rpm"
echo "kernel-debuginfo-`uname -r`.rpm"

下载debuginfo

wget http://debuginfo.centos.org/7/x86_64/kernel-debuginfo-common-x86_64-`uname -r`.rpm
wget http://debuginfo.centos.org/7/x86_64/kernel-debuginfo-`uname -r`.rpm

安装

yum install kernel-debuginfo-common-x86_64-3.10.0-693.2.2.el7.x86_64.rpm
yum install kernel-debuginfo-3.10.0-693.2.2.el7.x86_64.rpm

3 编译内核

重新编译内核，top-level Makefile增加：

CFLAGS_KERNEL := -g
CFLAGS := -g

make clean; make to create the vmlinux kernel file with debug information

（可选）4 内核源码

uname -r后找对应版本

https://vault.centos.org/7.4.1708/os/Source/SPackages/

参考