随笔分类 -  kernel

kernel 学习积累
kennel boot-parameters
摘要：normal we use bootloader paramer , but sometimes we may want to use extern kernel-parameters, or Always use the default kernel command string...... ex 阅读全文
posted @ 2020-09-14 10:36 嵌入式实操 阅读(152) 评论(0) 推荐(0)
kernel dump_stack
摘要：#cat /sys/class/graphics/fb0/fsl_disp_dev_property CPU: 1 PID: 12732 Comm: sh Not tainted 4.1.15 #8Hardware name: Freescale i.MX6 Quad/DualLite (Devic 阅读全文
posted @ 2020-09-07 10:51 嵌入式实操 阅读(406) 评论(0) 推荐(0)
kernel optimize debug interface
摘要：in init/main.c -bool initcal_debug +bootl initcall_debug = true; CONFIG_PRINTK_TIME=y General setup > Kernel compression mode (LZ0) 阅读全文
posted @ 2020-08-25 19:38 嵌入式实操 阅读(178) 评论(0) 推荐(0)
kernel power-save interface
摘要：/sys/power/state echo mem > /sys/power/state echo freeze > /sys/power/state echo standby > /sys/power/state 阅读全文
posted @ 2020-08-25 19:36 嵌入式实操 阅读(203) 评论(0) 推荐(0)
kernel enable /dev/mem
摘要：enable options: +CONFIG_DEVMEM +CONFIG_KDEVMEM +CONFIG_STRICT_DEVMEM 阅读全文
posted @ 2020-08-25 19:31 嵌入式实操 阅读(369) 评论(0) 推荐(0)
kernel sysrq
摘要：echo i > /proc/sysrq-trigger Send a SIGKILL to all process, except for init; 阅读全文
posted @ 2020-08-25 19:26 嵌入式实操 阅读(255) 评论(0) 推荐(0)
kernel enable specific directory DEBUG
摘要：Example: driver/media/Makefile +ccflags-y := -DDEBUG 阅读全文
posted @ 2020-08-25 19:23 嵌入式实操 阅读(110) 评论(0) 推荐(0)
kernel lcd blank interface
摘要：enable lcd blank #echo 1 > /sys/class/graphics/fb0/blank disalbe lcd blank #echo 0 > /sys/class/graphics/fb0/blank 阅读全文
posted @ 2020-07-14 15:46 嵌入式实操 阅读(315) 评论(0) 推荐(0)
kernel parameter [nosmp | maxcpus=0]
摘要：强制让内核按单核模式启动 在启动参数里追加 nosmp 或者 maxcpus=0 kernel-parameters的说明如下: nosmp [SMP] Tells an SMP kernel to act as a UP kernel,and disable the IO APIC. legacy 阅读全文
posted @ 2020-07-04 09:11 嵌入式实操 阅读(639) 评论(0) 推荐(0)
kernel get clock info
摘要：root@vmuser:~# cat /sys/kernel/debug/clk/clk_summary clock enable_cnt prepare_cnt rate accuracy phase 阅读全文
posted @ 2020-07-04 09:07 嵌入式实操 阅读(349) 评论(0) 推荐(0)
kernel bootargs consoleblank
摘要：禁止屏幕休眠 consoleblank=0 阅读全文
posted @ 2020-07-04 09:00 嵌入式实操 阅读(407) 评论(0) 推荐(0)
kernel CONFIG_FRACE
摘要：编写应用程序时，如果查看函数的实际执行效率，就可以选择开启内核的CONFIG_FTRACE选项。 上层通过perf-tools配合，就可以查看指定程序的调用情况。 root@vmuser:~/tmp/perf-tools# ./bin/uprobe -s p:/root/a.out:signalHa 阅读全文
posted @ 2020-07-04 08:58 嵌入式实操 阅读(145) 评论(0) 推荐(0)
kernel page_size
摘要：内核空间查看page size arch/arm/include/asm/page.h #define PAGE_SHIFT 12 #define PAGE_SIZE ( 1<< PAGE_SHIFT) 应用层： # getconf PAGESIZE 4096 #include <unistd.h> 阅读全文
posted @ 2020-07-04 08:50 嵌入式实操 阅读(1314) 评论(0) 推荐(0)
kernel cpu_cur_freq
摘要：# cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq 获取CPU当前的注频 阅读全文
posted @ 2020-06-09 19:23 嵌入式实操 阅读(414) 评论(0) 推荐(0)
kernel printk
摘要：#echo 8 > /proc/sys/kernle/printk 更改printk级别 阅读全文
posted @ 2020-06-09 19:22 嵌入式实操 阅读(248) 评论(0) 推荐(0)
kernel namespace
摘要：reference: https://lwn.net/Articles/531114/ 阅读全文
posted @ 2019-06-13 14:07 嵌入式实操 阅读(159) 评论(0) 推荐(0)
kernel build command
摘要：Uboot: make ARCH=arm CROSS_COMPILE=${CC} distclean make ARCH=arm CROSS_COMPILE=${CC} am335x_evm_defconfig make ARCH=arm CROSS_COMPILE=${CC} Kernel: ma 阅读全文
posted @ 2019-01-24 09:08 嵌入式实操 阅读(174) 评论(0) 推荐(0)
kernel jenkins build script
摘要：kernel;jenkins; 阅读全文
posted @ 2019-01-23 08:56 嵌入式实操 阅读(298) 评论(0) 推荐(0)