An introduction to kernel synchronization 当一个thread正在对数据进行读写操作时,另一个thread对同一个数据进行读写操作,这就会产生冲突竞争,比如重写数据单元等。为了解决这样的问题,必须考虑synchronization的问题。这样的竞争问题,并不总是能够复现,所以调试起来也比较困难。 这个需要被保护,防止被改变的section,称为...
这段代码在单线程(在linux下就是单进程,因为linux没有严格的线程概念,linux只有进程)下运行是没有问题的,但是在多线程情况下,会包含着一个隐含的问题,这个问题需要从"--printer"的汇编代码才能看出,在x86平台上,"--printer"指令可能会被编译成如下的汇编指令 # printer--movl printer%eax decl%eax movl%eax print...
Linux, like some schedulers, distinguishes between one more type of process: a real-time process. Real-time processes must execute in real time. Linux has support for real-time processes, but those exist outside of the scheduler logic. Put simply, the Linux scheduler treats any process marked...
Chapter 5. Kernel Synchronization You could think of the kernel as a server that answers requests; these requests can come either from a process running on a CPU or an … - Selection from Understanding the Linux Kernel, Second Edition [Book]
Chapter 5. Kernel Synchronization You could think of the kernel as a server that answers requests; these requests can come either from a process running on a CPU or an … - Selection from Understanding the Linux Kernel, 3rd Edition [Book]
每个进程中,都对应有一个css_set结构体,css_set其实就是cgroup_subsys_state对象的集合,而每个cgroup_subsys_state代表一个subsystem。下面是css_set结构体的定义: linux-4.4.19/include/linux/cgroup-defs.h #154 代码语言:javascript 代码运行次数:0
The first synchronization primitive of this type will be already familiar for us - semaphore. As in all previous parts of this book, before we will consider implementation of thereader/writer semaphoresin the Linux kernel, we will start from the theoretical side and will try to understand what...
Actually the Linux kernel does not provideget_seq_counter_val()function. Here it is just a stub. Like a__retry__too. As I already wrote above, we will see actual the API for this in the next paragraph of this part. Ok, now we know what aseqlocksynchronization primitive is and how ...
Linux内核中实现了一套经典的链表操作,定义在/include/linux/list.h文件中,本文基于linux内核源码6.2.7,记录了其常用操作链表的API函数,便于在阅读linux内核源码时更好的理解程序执行的过程和细节。 一、链表数据结构 定义在/include/linux/types.h文件中: ...
Synchronization Technique to Improve User-Level Performance in Kernel-Level EnvironmentThe most common use of RCU within the Linux kernel is as a replacement for reader-writer locking in read- intensive situations. Nevertheless, this use of RCU was not immediately apparent to me at the outset, in...