smp preempt

Original website: http://www.ibm.com/developerworks/cn/linux/l-cn-linuxkernelint/index.html Brief Introduction: This article has carried on the thorough analysis and the discussion to the interrupt system, mainly includes the interruption controller, the interruption classification, the interruption affinity, the interrupt migration and so on in the disconnection process and SMP. Firstly, the principle of interruption is briefly analyzed, then the r

Spin Lock thinking: http://bbs.chinaunix.net/thread-2333160-1-1.htmlrecently in See Song Baohua "device driver development Specific explanation" second edition. See the spin lock part, some doubts. So come and ask the people. Here are some of the ideas I've got from some of the online information that I've come up with, and I don't know right or wrong. Let's write it down and discuss it:(1) There are three implementations of spin locks on Linux:1. On a single CPU. Cannot

Spin Lock thinking: http://bbs.chinaunix.net/thread-2333160-1-1.htmlrecently in See Song Baohua "device driver Development detailed" Second edition, see the Spin lock part, some doubts, so come to ask everyone. Here are some of the ideas I've drawn from some of the web's information, whether it's right or not, and what we're talking about:(1) There are three implementations of spin locks on Linux:1. In a single CPU, cannot preempt the kernel, the spin

simulation interrupt, so called soft interrupt.A soft interrupt does not preempt another soft interrupt, only a hardware interrupt can preempt the soft interrupt, so a hard interrupt can guarantee a strict time requirement. The origin of soft interrupts http://blog.chinaunix.net/uid-27717694-id-3807979.html The Linux bottom half (hereinafter referred to as BH) mechanism has two drawbacks, namely:

that acquires the lock and interrupts form a race condition) analogy: The current thread acquires a spin lock. Interrupt handlers interrupt the interrupt handler in the critical section to get the lock, and the interrupt handler waits for the current thread to release the lock, while the current thread waits for the break to run before the critical section and the code to release the lock.The use of a spin lock in the operation of the lower half of the interrupt handling is especially necessary

a race condition) For example: After the current thread acquires a spin lock, the interrupt handler is interrupted in the critical section, and then the interrupt handler waits for the lock to be released. The current thread is also waiting for the code to execute the critical section and release the lock after the interrupt has been executed.The use of a spin lock in the operation of the lower half of the interrupt handling is especially necessary for caution:1. When the lower half of processi

Transferred from: http://www.ibm.com/developerworks/cn/linux/l-cn-linuxkernelint/In this paper, the interrupt system is analyzed and discussed, including interrupt controller, interrupt classification, interrupt affinity, interrupt transfer and interruption migration in SMP. Firstly, the principle of interrupt operation is briefly analyzed, and then the realization principle of interrupt affinity is discussed in detail, and the mechanism of the proces

Http://www.ibm.com/developerworks/cn/linux/l-cn-linuxkernelint/index.htmlIn this paper, the interrupt system is analyzed and discussed, including interrupt controller, interrupt classification, interrupt affinity, interrupt transfer and interruption migration in SMP. Firstly, the principle of interrupt operation is briefly analyzed, and then the realization principle of interrupt affinity is discussed in detail, and the mechanism of the process of dis

Of the current version 2.6 kernel, there are three possible options: Softirq, Tasklet, and Work queue. Tasklet is based on SOFTIRQ implementations, so the two are very similar. The work queue is completely different from them, and it is implemented by kernel threading. 1, SOFTIRQ Soft interrupts support SMP, and the same SOFTIRQ can be run concurrently on different CPUs, SOFTIRQ must be reentrant. Soft interrupts are statically allocated during compil

symbol used in the module is inconsistent with the verification string of the corresponding kernel symbol exported by the current running kernel, that is, the current kernel space does not have the kernel symbol used by the module, and the "Invalid module format" error will occur.Adding a verification string to the kernel symbol to verify whether the module version matches the kernel version is complicated and wastes kernel space. In addition, with SMP