20230517提升cv1826的打印等级
2023/5/17 17:43
https://www.xitongjiaocheng.com/linux/2017/53494.html
Linux内核log等级与printk打印消息控制
时间：2017-03-13 出处：系统之家复制分享人气(206次) 【大中小】
printk打印消息控制
// linux/include/printk.h
#define MESSAGE_LOGLEVEL_DEFAULT CONFIG_MESSAGE_LOGLEVEL_DEFAULT
#define CONSOLE_LOGLEVEL_DEFAULT 7
#define CONSOLE_LOGLEVEL_MIN 1
#define CONSOLE_LOGLEVEL_DEFAULT 7
rootroot@rootroot-X99-Turbo:~/smartpen$
rootroot@rootroot-X99-Turbo:~/smartpen$ find . -name printk.c
./linux/kernel/printk/printk.c
rootroot@rootroot-X99-Turbo:~/smartpen$ find . -name printk.h
./linux/build/cv1826_wevb_0005a/include/config/printk.h
./linux/include/trace/events/printk.h
./linux/include/linux/printk.h
./linux/tools/virtio/linux/printk.h
rootroot@rootroot-X99-Turbo:~/smartpen$
1、
Z:\smartpen\linux\include\linux\printk.h
#define CONSOLE_EXT_LOG_MAX 8192
/* printk's without a loglevel use this.. */
#define MESSAGE_LOGLEVEL_DEFAULT CONFIG_MESSAGE_LOGLEVEL_DEFAULT
/* We show everything that is MORE important than this.. */
#define CONSOLE_LOGLEVEL_SILENT 0 /* Mum's the word */
#define CONSOLE_LOGLEVEL_MIN 1 /* Minimum loglevel we let people use */
#define CONSOLE_LOGLEVEL_DEBUG 10 /* issue debug messages */
#define CONSOLE_LOGLEVEL_MOTORMOUTH 15 /* You can't shut this one up */
/*
* Default used to be hard-coded at 7, quiet used to be hardcoded at 4,
* we're now allowing both to be set from kernel config.
*/
#define CONSOLE_LOGLEVEL_DEFAULT CONFIG_CONSOLE_LOGLEVEL_DEFAULT
#define CONSOLE_LOGLEVEL_QUIET CONFIG_CONSOLE_LOGLEVEL_QUIET
extern int console_printk[];
修改为：
#define CONSOLE_EXT_LOG_MAX 8192
/* printk's without a loglevel use this.. */
#define MESSAGE_LOGLEVEL_DEFAULT 7
/* We show everything that is MORE important than this.. */
#define CONSOLE_LOGLEVEL_SILENT 0 /* Mum's the word */
#define CONSOLE_LOGLEVEL_MIN 7 /* Minimum loglevel we let people use */
#define CONSOLE_LOGLEVEL_DEBUG 10 /* issue debug messages */
#define CONSOLE_LOGLEVEL_MOTORMOUTH 15 /* You can't shut this one up */
/*
* Default used to be hard-coded at 7, quiet used to be hardcoded at 4,
* we're now allowing both to be set from kernel config.
*/
#define CONSOLE_LOGLEVEL_DEFAULT 7
#define CONSOLE_LOGLEVEL_QUIET CONFIG_CONSOLE_LOGLEVEL_QUIET
extern int console_printk[];
调试记录：
# cat /proc/sys/kernel/printk
7 7 7 7
2、【可能不需要，需要进一步确认！】
Z:\smartpen\linux\kernel\printk\printk.c
将全部的LOGLEVEL_DEFAULT替换为7。
int do_syslog(int type, char __user *buf, int len, int source)
{
bool clear = false;
static int saved_console_loglevel = LOGLEVEL_DEFAULT;
int error;
修改为：
int do_syslog(int type, char __user *buf, int len, int source)
{
bool clear = false;
static int saved_console_loglevel = 7;
int error;
/* Disable logging to console */
case SYSLOG_ACTION_CONSOLE_OFF:
if (saved_console_loglevel == LOGLEVEL_DEFAULT)
saved_console_loglevel = console_loglevel;
console_loglevel = minimum_console_loglevel;
break;
/* Enable logging to console */
case SYSLOG_ACTION_CONSOLE_ON:
if (saved_console_loglevel != LOGLEVEL_DEFAULT) {
console_loglevel = saved_console_loglevel;
saved_console_loglevel = LOGLEVEL_DEFAULT;
}
break;
/* Set level of messages printed to console */
case SYSLOG_ACTION_CONSOLE_LEVEL:
if (len < 1 || len > 8)
return -EINVAL;
if (len < minimum_console_loglevel)
len = minimum_console_loglevel;
console_loglevel = len;
/* Implicitly re-enable logging to console */
saved_console_loglevel = LOGLEVEL_DEFAULT;
break;
修改为：
/* Disable logging to console */
case SYSLOG_ACTION_CONSOLE_OFF:
if (saved_console_loglevel == 7)
saved_console_loglevel = 7;
console_loglevel = 7;
break;
/* Enable logging to console */
case SYSLOG_ACTION_CONSOLE_ON:
if (saved_console_loglevel != LOGLEVEL_DEFAULT) {
console_loglevel = 7;
saved_console_loglevel = 7;
}
break;
/* Set level of messages printed to console */
case SYSLOG_ACTION_CONSOLE_LEVEL:
if (len < 1 || len > 8)
return -EINVAL;
if (len < minimum_console_loglevel)
len = minimum_console_loglevel;
console_loglevel = 7;
/* Implicitly re-enable logging to console */
saved_console_loglevel = LOGLEVEL_DEFAULT;
break;
3、【改这里改乱了！】
Z:\smartpen\linux\build\cv1826_wevb_0005a\.config
Z:\smartpen\build\boards\cv1826_wevb_0005a\linux\cvitek_cv1826_wevb_0005a_defconfig
# printk and dmesg options
#
CONFIG_PRINTK_TIME=y
CONFIG_CONSOLE_LOGLEVEL_DEFAULT=7
CONFIG_CONSOLE_LOGLEVEL_QUIET=4
CONFIG_MESSAGE_LOGLEVEL_DEFAULT=7
# CONFIG_BOOT_PRINTK_DELAY is not set
CONFIG_DYNAMIC_DEBUG=y
修改为：
# printk and dmesg options
#
CONFIG_PRINTK_TIME=y
CONFIG_CONSOLE_LOGLEVEL_DEFAULT=8
CONFIG_CONSOLE_LOGLEVEL_QUIET=8
CONFIG_MESSAGE_LOGLEVEL_DEFAULT=8
# CONFIG_BOOT_PRINTK_DELAY is not set
CONFIG_DYNAMIC_DEBUG=y
调试记录：
# cat /proc/sys/kernel/printk
4 4 1 8
#
参考资料：
默认 buildroot 打印等级7
https://blog.csdn.net/weixin_29101181/article/details/119544911
五、prink的使用以及console控制日志输出级别
拓展:产品发布时候，我们一般都不会希望用户可以通过串口进入我们的系统后台，因此会主动把调试串口给关掉，在内核编译配置文件中CONFIG_SERIAL_IMX_CONSOLE=y
CONFIG_MESSAGE_LOGLEVEL_DEFAULT=7
https://www.wenjiangs.com/article/sysklogd.html
Sysklogd 系统日志记录器
发布于 2021-01-11 13:11:26 字数 11723 浏览 933 评论 0
内核的控制台日志等级
内核的控制台日志等级控制哪些内核消息会在控制台上显示。有两种途径可以修改这个等级，一种是通过内核引导参数，另一种，也是建议的途径是通过 sysctl 来控制，通常这个设置位于 /etc/sysctl.conf 中。比如：
kernel.printk = 4 4 1 7
[注意]控制台日志等级与内核消息等级是不同的概念，默认的内核消息等级(DEFAULT_MESSAGE_LOGLEVEL)是由内核在编译时确定的(CONFIG_DEFAULT_MESSAGE_LOGLEVEL)，其默认值是"4"(WARNING)。而默认的控制台日志等级(DEFAULT_CONSOLE_LOGLEVEL)是"7"(debug)，其含义是等级数字小于等于6的消息(优先级更高)都会显示在控制台上。
https://blog.csdn.net/zifehng/article/details/60763837
Linux内核log等级与printk打印消息控制
zifehng 于 2017-03-07 14:30:51 发布
通过procfs控制printk打印消息
1. 查看当前printk打印消息的log等级
# cat /proc/sys/kernel/printk
# 7 4 1 7
“7 4 1 7” 分别对应console_loglevel、default_message_loglevel、minimum_c onsole_loglevel、default_console_loglevel，意味着只有优先级高于KERN_DEBUG(7)的打印消息才能输出到终端
2. 改变console_loglevel
# echo 8 4 1 7 > /proc/sys/kernel/printk
输入“8 4 1 7”改变console_loglevel值，使得所有的打印消息都能输出到终端
linux 打印等级 printk
http://www.taodudu.cc/news/show-3609554.html?action=onClick
linux内核中printk的打印级别