在Linux中,处理器所作的事可以归纳为3种情况: 1.In user-space, executing user code in a process; 2.In kernel-space, in process context, executing on behalf of a specific process; 3.In kernel-space, in interrupt context, not associated with a process, handling an interru…

This chapter introduces some conception about kernel synchronization generally. Critical Regions: Code paths that access and manipulate shared data. Race Condition: Two threads of execution to be simultaneously executing within the same critical regi…

In 2.6.x, there are 3 mechanisms for implementing a bottom half: softirqs, tasklets and work queues. Here's the comparison: Softirqs: Softirqs are statically allocated at compile time. It is represented by the softirq_action structure, which is defin…

Recently I realized my English is still far from good. So in order to improve my English, I must not only read in English, but also think and write in English. I know I'm gonna make a lot of mistake in using English, but everything has a process so I…

这一章我们研究四种主要的数据结构: linked lists, queues, maps, binary trees. Linked Lists:(<linux/list.h>) 在linux中,并不是直接将某个结构体作为链表的节点,而是在该结构中插入一个链表的节点.借助container_of()这个宏,我们可以轻松的找到包含给定成员变量的父结构. Linux kernel中一般使用的是循环双链表. 正常遍历使用的是list_for_each()宏,但是当遍历过程中删除某个表项时就有可能出错…

imx6开机启动就进入download模式,有的板子进入文件系统之后会进入download模式.查看datasheet,Chapter 8 System Boot查找原因,记录于此. freescale论坛有关于这个问题的讨论,有硬件也有软件方面的原因. 参考链接 https://community.nxp.com/thread/316232 https://community.nxp.com/thread/338433 boot mode pin settings 8.2.1 Boot mod…

halcon的算子列表   Chapter 1 :Classification 1.1 Gaussian-Mixture-Models 1.add_sample_class_gmm 功能:把一个训练样本添加到一个高斯混合模型的训练数据上. 2.classify_class_gmm 功能:通过一个高斯混合模型来计算一个特征向量的类. 3. clear_all_class_gmm 功能:清除所有高斯混合模型. 4. clear_class_gmm 功能:清除一个高斯混合模型. 5. clear_sa…

Chapter 1 :Classification 1.1 Gaussian-Mixture-Models 1.add_sample_class_gmm 功能:把一个训练样本添加到一个高斯混合模型的训练数据上. 2.classify_class_gmm 功能:通过一个高斯混合模型来计算一个特征向量的类. 3. clear_all_class_gmm 功能:清除所有高斯混合模型. 4. clear_class_gmm 功能:清除一个高斯混合模型. 5. clear_samples_class_gm…

参考: 1)<ARM1176 JZF-S Technical Reference Manual>: Chapter 3 System Control Coprocessor Chapter 6 Memory Management Unit 2)u-boot源码: u-boot-x.x.x/cpu/s3c64xx/start.S u-boot-x.x.x/board/samsung/smdk6410/lowlevel_init.S 1. ARMv6 MMU简述 1)MMU由协处理器CP15控制:…

http://www.hawstein.com/posts/ctci-solutions-contents.html 作者:Hawstein出处:http://hawstein.com/posts/ctci-solutions-contents.html声明:本文采用以下协议进行授权: 自由转载-非商用-非衍生-保持署名|Creative Commons BY-NC-ND 3.0 ,转载请注明作者及出处. 前言 <Cracking the coding interview>是一本被许多人极力推…