driver irql

Windows NT assigns a priority to each hardware interrupt and a few software events, namely, the interrupt request level (interrupt request level-IRQL ). IRQL provides a synchronization method for activities on a single CPU Based on the following rules: Once a CPU runs on IRQL higher than passive_level, the activity on the CPU can only be preemptible by the ac

What is IRQL? IRQL is the interrupt request level and the interrupt request level. The processor executes the thread code on an IRQL. IRQL helps determine how a thread is interrupted. On the same processor, a thread can only be interrupted by a higher-level IRQL thread. Each

= DriverEntry; IRQL = passive_level Ntstatus DriverEntry (in pdriver_object pdriverobject, in punicode_string pregistrypath ){} 2. reinitialize (reinitialization routine) Pdriverobject-> driverreinitialize = driverreinitialize; 3. driverunload (uninstall routine) Pdriverobject-> DriverEntry = DriverEntry; 4. Shutdown (close the routine) Pdriverobject-> drivershutdown = drivershutdown; 5. bugcheck (fault detection routine) Pdriverobjec

The following table summarizes the IRQL and thread context requirements for file system filter driver dispatch routines. DriverEntryRoutines are called in the context of a system thread at IRQL = passive_level. Most drivers 'dispatch routines are called in an arbitrary threadContext at IRQL = passive_level, with the fo

Today, let's talk about IRQL, which is a nightmare for new users. Think about how much bsod is caused by IRQL mismatch. This is also one of the most popular sputation points for * nix kernel developers. You don't have this concept in Linux, and we are not very well-behaved? Sometimes I can get some blank space and ask the same question: Is it Mao? Mao must have this thing! Later I figured it out. Let's ta

allocate more resources to the shared buffer pool, resulting in crashes and system instability. When you activate this performance and the target computer has enough physical and virtual memory, the allocation of all drivers is automatically redirected to the special buffer pool. Extreme Memory Pressure Extreme Memory Pressure is set on a specific drive without affecting other drives (regardless of the system Memory size ). By indicating memory management, You can invalidate the callable code a

release a waiting thread. Lock OperationAmong the functions that the WDM driver can call, some functions can execute arithmetic operations in a thread-safe and multi-processor-safe way. These routines have two forms,The first form starts with interlocked. They can perform atomic operations.Other threads or CPUs cannot interfere with their execution.Another form starts with exinterlocked and uses spin locks. Table Lock Operation Service Functions Serv

The following is a list of precautions that developers should avoid when using the Windows NT Device Driver: Do not return status_pending through the scheduling routine without marking I/O Request Packet (IRP) suspension (iomarkirppending. Do not call kesynchronizeexecution through the interrupt service routine (ISR. It causes a system deadlock. Do not set deviceobject-> flags to do_buffered_io or do_direct_io. It will disrupt the system and event

The following is a list of precautions that developers should avoid when using the Windows NT Device Driver: 1. Do not return status_pending through the scheduling routine without marking I/O Request Packet (IRP) suspension (iomarkirppending. 2. Do not call kesynchronizeexecution through the interrupt service routine (ISR. It causes a system deadlock. 3. Do not set deviceobject-> flags to do_buffered_io or do_direct

The following is a list of precautions that developers should avoid when using the Windows NT Device Driver: Do not return status_pending through the scheduling routine without marking I/O Request Packet (IRP) suspension (iomarkirppending. Do not call kesynchronizeexecution through the interrupt service routine (ISR. It causes a system deadlock. Do not set deviceobject-> flags to do_buffered_io or do_direct_io. It will disrupt the system and even

The following is a list of precautions that developers should avoid when using the Windows NT Device Driver: 1. Do not return status_pending through the scheduling routine without marking I/O Request Packet (IRP) suspension (iomarkirppending. 2. Do not call kesynchronizeexecution through the interrupt service routine (ISR. It causes a system deadlock. 3. Do not set deviceobject-> flags to do_buffered_io or do_direc

Reprinted from: http://hi.baidu.com/zhanghuikl/blog/item/845478096f6878c53bc763ae.html 　 One major aspect of programming involves allocating storage units. Unfortunately, the driver cannot simply call malloc and free, or new or delete. To ensure that the correct type of memory is allocated, the allocated memory must be released after use, because the kernel mode code does not have an automatic clearing mechanism. Memory available for the

The following is a list of precautions that developers should avoid when using the Windows NT Device Driver: 1. Do not return status_pending through the scheduling routine without marking the iomarkirppending.2. Do not call kesynchronizeexecution through the interrupt service routine (ISR. It causes a system deadlock.3. Do not set deviceobject-> flags to do_buffered_io and do_direct_io. It will disrupt the system and eventually lead to fatal errors. I

processed, and initialize these routine entries in DriverEntry. A low-layer driver requires a startio, ISR, and dpcforisr routine. A synchcritsection routine may be required. If the device uses DMA, an adaptercontrol routine may be required.One or more iocompletion routines may be required for high-level drivers, at least completing the I/O status checkAnd then call iocompleterequest. If necessary, modify the data structure and content of device exte

Linux driver development focuses on content-from "embedded Linux driver template overview and project practices", embedded driver development This article is excerpted from my lecture on Embedded Linux driver templates and project practices. Initially, it seems that the development of Linux Device Drivers involves a lo

Linux Device Driver category, character device driver, how to add cdev to the kernel ?, Driver category cdev 1. Linux Device Driver category By hardware of Managed Devices Character Device Access by byte streams, which can be accessed sequentially or at specified locations Touch screen LCD for serial port terminals Bl

Character Device Driver instance With the foundation of the previous section, I will learn how to compile a character device driver and test it on the client to verify whether the character device driver has been created successfully.1. Character Device Driver The following is the

Android system transplantation and driver development-Chapter 7-LED driver and android driver development Implementation principle of LED Driver Write LED driver: Before testing the LED driver, you need to use a USB data cable to

I. NIC Driver Installation My network adapter information: Network Adapter jmicron PCI Express Gigabit Ethernet Adapter Interface Type: Gigabit Ethernet Install the compilation tool gcc Download DRIVER: jme-1.0.7.tbz2 Step 1: Decompress jme-1.0.5.tbz2# Tar xjvf jme-1.0.7.tbz2 Step 2: Change directory to jme-1.0.5 # Cd jme-1.0.7 Step 3: Compile driver with roo

[Video] Secrets of Embedded Linux/Android driver development (1) Touch Screen driver development and android driver development Secrets of Embedded Linux/Android driver development (1) Touch Screen driver development Topic Introduction: Since samurst invented the world's fi