Description: In a preemptive priority based RTOS, priority inversion
problem is among the major sources of deadline
violations. Priority inheritance protocol is one of the
approaches to reduce priority inversion. Unfortunately,
RTOS like uC/OS can’t support priority inheritance
protocol since it does not allow kernel to have multiple
tasks at the same priority. Although it has different ways
to avoid priority inversion such as priority ceiling
protocol, developers still have some difficulties in
programming real time applications with it. In this paper,
we redesign the uC/OS kernel to provide the ability to
support round robin scheduling and implement priority
inheritance semaphore on the modified kernel. As result,
we port new kernel with priority inheritance semaphore to
evaluation board, and evaluate the execution time of each
of the kernel service as well as verify the operations of
our implementation. Platform: |
Size: 135878 |
Author:刘天宏 |
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Description: The main purpose of this project is to add a new scheduling algorithm to GeekOS and to implement a simple synchronization primitive (semaphore). As you might have already noticed, GeekOS uses a simple priority based preemptive Round Robin algorithm. In this project, you will change this to a multilevel feedback scheduling. In addition, you will provide user programs with semaphores, a means to check the system s current time and a mechanism for passing command-line arguments Platform: |
Size: 589155 |
Author:向东 |
Hits:
Description: In a preemptive priority based RTOS, priority inversion
problem is among the major sources of deadline
violations. Priority inheritance protocol is one of the
approaches to reduce priority inversion. Unfortunately,
RTOS like uC/OS can’t support priority inheritance
protocol since it does not allow kernel to have multiple
tasks at the same priority. Although it has different ways
to avoid priority inversion such as priority ceiling
protocol, developers still have some difficulties in
programming real time applications with it. In this paper,
we redesign the uC/OS kernel to provide the ability to
support round robin scheduling and implement priority
inheritance semaphore on the modified kernel. As result,
we port new kernel with priority inheritance semaphore to
evaluation board, and evaluate the execution time of each
of the kernel service as well as verify the operations of
our implementation.-In a preemptive priority based RTOS, priority inversionproblem is among the major sources of deadlineviolations. Priority inheritance protocol is one of theapproaches to reduce priority inversion. Unfortunately, RTOS like uC/OS can t support priority inheritanceprotocol since it does not allow kernel to have multipletasks at the same priority. Although it has different waysto avoid priority inversion such as priority ceilingprotocol, developers still have some difficulties inprogramming real time applications with it. In this paper, we redesign the uC/OS kernel to provide the ability tosupport round robin scheduling and implement priorityinheritance semaphore on the modified kernel. As result, we port new kernel with priority inheritance semaphore toevaluation board, and evaluate the execution time of eachof the kernel service as well as verify the operations ofour implementation. Platform: |
Size: 135168 |
Author:刘天宏 |
Hits:
Description: 用以演示他提出的信号量机制。本作业要求设计在同一个进程地址空间内执行的两个线程。生产者线程生产物品，然后将物品放置在一个空缓冲区中供消费者线程消费。-For the presentation he made semaphore mechanism. Operational requirements of the design process in the same address space to implement the two threads. Thread the production of goods producers, and then the article should be placed in an empty buffer for consumers thread consumption. Platform: |
Size: 1024 |
Author:刘军 |
Hits:
Description: 用以演示他提出的信号量机制。本作业要求设计在同一个进程地址空间内执行的两个线程。生产者线程生产物品，然后将物品放置在一个空缓冲区中供消费者线程消费。-For the presentation he made semaphore mechanism. Operational requirements of the design process in the same address space to implement the two threads. Thread the production of goods producers, and then the article should be placed in an empty buffer for consumers thread consumption. Platform: |
Size: 1024 |
Author:刘军 |
Hits:
Description: 用以演示他提出的信号量机制。本作业要求设计在同一个进程地址空间内执行的两个线程。生产者线程生产物品，然后将物品放置在一个空缓冲区中供消费者线程消费。-For the presentation he made semaphore mechanism. Operational requirements of the design process in the same address space to implement the two threads. Thread the production of goods producers, and then the article should be placed in an empty buffer for consumers thread consumption. Platform: |
Size: 4096 |
Author:刘军 |
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Description: μC/OS从1992年开始为人们熟悉，到现在已经发展为μC/OS-II。ΜC/OS-II最多支持56个任务，其内核为占先式，总是执行就绪态的优先级最高的任务，并支持Semaphore（信号量）、Mailbox（邮箱）、Message Queue(消息队列)等多种常用的进程间通信机制。与大多商用RTOS不同的是，μC/OS-II公开所有的源代码，并可以免费获得，对商业应用收取少量License费用。-μC/OS since 1992 to people familiar with until now has been developed for μC/OS-II. ΜC/OS-II supports up to 56 tasks, the kernel for Preemptive always ready state to implement the highest priority tasks, and to support the Semaphore (Semaphore), Mailbox (mail), Message Queue (Message Queue), etc. a wide range of commonly used interprocess communication mechanism. Most of the commercial RTOS and the difference is, μC/OS-II open all the source code, and can be obtained free of charge a small business applications License fees. Platform: |
Size: 8192 |
Author:ttjj120 |
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Description: The main purpose of this project is to add a new scheduling algorithm to GeekOS and to implement a simple synchronization primitive (semaphore). As you might have already noticed, GeekOS uses a simple priority based preemptive Round Robin algorithm. In this project, you will change this to a multilevel feedback scheduling. In addition, you will provide user programs with semaphores, a means to check the system s current time and a mechanism for passing command-line arguments Platform: |
Size: 588800 |
Author:向东 |
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Description: Purpose
Aim to setup a small system above the OS layer , implement the message queue of process or thread and simulate the function of watchdog used to detect the deadlock of the system.
- introduction
1. Purpose
Aim to setup a small system above the OS layer , implement the message queue of process or thread and simulate the function of watchdog used to detect the deadlock of the system.
2. Method
Using window API to create serval thread and create a message queue for each thread to control the message exchange between the different treads.
3. Files
Projectmain.h------ structs , enums ,and claim of functions
ThreadSemaphore.c------- extend the Windows semaphore API
ThreadQueue.c------- message queue file (send to, receive from ,create and destroy queue )
ThreadFrame.c-- 1) create all the task for test
2) control the message handling
3) control the thread running
4)functions of watchdog
5) a hardware timer simulator to create timeout message every 1 sec
4 task :
Thread_IDLE,-- lowest prority , interact with user and obtain a semaphore which will be waitted by Thread_LOST later
Platform: |
Size: 1002496 |
Author:Xiwen |
Hits:
Description: 实验一 用信号量来实现读者-写者问题
(一) 实验目的
理解进程(或线程)及信号量的概念
(二) 实验内容
1、定义一个数据缓存buffer及用于实现同步互斥的信号量。
2、定义一个读者函数：
当有写者在占用buffer时，读者应该等待，直到写者不再使用该buffer。
当有其他读者在占用buffer时，读者可对buffer进行读取操作。
当buffer中有数据时，则从其中读取一个数据，并显示然后退出。
当buffer中没有数据时，应等待，直到buffer中有数据可读。
3、定义一个写者函数
当有读者在占用buffer时，写者应该等待，直到所有的读者都退出为止。
当有其他写者占用buffer时，该写者应该等待，直到占用buffer的写者退出为止。
当buffer有空闲时，写者应该在buffer中写入一个数据并退出。
当buffer满时，写者应该等待，直到buffer有空闲为止。
4、定义主函数，在其中可以任意创建读者与写者。
可根据用户输入创建读者或写者进程(线程)。
5、用户界面
(三) 实验要求
在实验过程中，显示详细的各进程(线程)的状态及buffer使用情况。
(四) 实验学时 3-Experiments using semaphore to implement a reader- writer problem
(A) purpose of the experiment
Understand the process (or thread), and the concept of semaphore
(b) of the experiment content
1, define a data cache buffer, and synchronization for mutual exclusion semaphore.
2, the definition of a reader function:
When a write buffer in the occupation, the reader should wait until the writer is no longer used in the buffer.
When there are other readers in the occupied buffer, the reader can read buffer operations.
When the buffer has data, from which a data read and displayed and then exit.
When the buffer contains no data, they should wait until the buffer has data to read.
3, define the function of a writer
When a reader occupied buffer, the writer should wait until all of the readers exit.
When the buffer occupied by other writers, the writer should wait until the write buffer occupied by exit.
When the buffer in their free time to write should be written in a Platform: |
Size: 2048 |
Author:镡皓琳 |
Hits:
Description: 实验一 用信号量来实现读者-写者问题
(一) 实验目的
理解进程(或线程)及信号量的概念
(二) 实验内容
1、定义一个数据缓存buffer及用于实现同步互斥的信号量。
2、定义一个读者函数：
当有写者在占用buffer时，读者应该等待，直到写者不再使用该buffer。
当有其他读者在占用buffer时，读者可对buffer进行读取操作。
当buffer中有数据时，则从其中读取一个数据，并显示然后退出。
当buffer中没有数据时，应等待，直到buffer中有数据可读。
3、定义一个写者函数
当有读者在占用buffer时，写者应该等待，直到所有的读者都退出为止。
当有其他写者占用buffer时，该写者应该等待，直到占用buffer的写者退出为止。
当buffer有空闲时，写者应该在buffer中写入一个数据并退出。
当buffer满时，写者应该等待，直到buffer有空闲为止。
4、定义主函数，在其中可以任意创建读者与写者。
可根据用户输入创建读者或写者进程(线程)。
5、用户界面
(三) 实验要求
在实验过程中，显示详细的各进程(线程)的状态及buffer使用情况。
(四) 实验学时 3-Experiments using semaphore to implement a reader- writer problem
(A) purpose of the experiment
Understand the process (or thread), and the concept of semaphore
(b) of the experiment content
1, define a data cache buffer, and synchronization for mutual exclusion semaphore.
2, the definition of a reader function:
When a write buffer in the occupation, the reader should wait until the writer is no longer used in the buffer.
When there are other readers in the occupied buffer, the reader can read buffer operations.
When the buffer has data, from which a data read and displayed and then exit.
When the buffer contains no data, they should wait until the buffer has data to read.
3, define the function of a writer
When a reader occupied buffer, the writer should wait until all of the readers exit.
When the buffer occupied by other writers, the writer should wait until the write buffer occupied by exit.
When the buffer in their free time to write should be written in a Platform: |
Size: 122880 |
Author:镡皓琳 |
Hits:
Description: 实现一个进程，该进程拥有一个生产者线程和一个消费者线程，它们使用32个不同的缓冲区。使用如下信号量：
（1）一个互斥信号量，用以阻止生产者线程和消费者线程同时操作缓冲区列表；
（2）一个信号量，当生产者线程生产出一个物品时可以用它向消费者线程发出信号；
-Implement a process that has a producer thread and a consumer thread, they use 32 different buffers. Semaphore using the following: (1) a mutex to prevent the producer and consumer threads simultaneously thread the buffer list (2) a semaphore, when the producer thread to produce an item can use it to consumers to signal the thread Platform: |
Size: 2048 |
Author:Andy |
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Description: Ucore是一个很小的适于学习的操作系统，此“麻雀”包含虚存管理、进程管理、处理器调度、同步互斥、进程间通信、文件系统等主要内核功能，总的内核代码量（C+asm）不会超过5K行。充分体现了“小而全”的指导思想。
这是ucore的实验5：进程同步。实验目的：熟悉ucore中的进程同步机制，了解操作系统为进程同步提供的底层支持；在ucore中实现信号量（semaphore）机制；理解管程机制，在ucore中增加对条件变量（condition variable）的支持；了解经典进程同步问题，并使用现有同步机制解决进程同步问题。-Ucore is a small operating system for learning, the " Sparrow" contains the virtual memory management, process management, processor scheduling, synchronization mutually exclusive, inter-process communication, file system and other major kernel functions, the total amount of kernel code ( C+ asm) no more than 5K lines. Fully embodies the " small" the guiding ideology. This is ucore experiment 5: the process of synchronization. Purpose: familiar ucore in the process of synchronization mechanisms, understanding of the operating system to provide underlying support for process synchronization in ucore implement semaphore (semaphore) mechanism understand the management process mechanism, the increase in ucore condition variable (condition variable) of support understand the classical process synchronization, and synchronization mechanisms to use existing settlement process synchronization problem. Platform: |
Size: 1002496 |
Author:gyh |
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Description: 1 编写单进程多线程程序，实现一个线程A将另外一个线程B的从标准输入的字符串反序输出。
2 编写单进程多线程程序，用信号量实现一个线程A随机生成一个0-100的整数，另外一个线程B将此数平方后打印输出，要求每秒钟显示一次。
3 编写单进程多线程程序，用互斥锁实现一个线程A随机生成一个0-100的整数，另外一个线程B将此数平方后打印输出，要求每秒钟显示一次。-A single process writing multi-threaded program, implement a thread A thread B will be another string from standard input output in reverse order. 2 single-process multi-threaded programs written using semaphore to implement a thread A generates a random integer 0-100, another thread B after this number of square printed output, requires a second display. 3 single-process multi-threaded programs written using a thread mutex to achieve a 0-100 A randomly generated integer, another thread B after this number of square printed output, requires a second display. Platform: |
Size: 2048 |
Author:wangjian |
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Description: For those wishing to develop multi-threaded applications in a C++ class oriented
environment. This library allows creation of threads as classes as well as
access to multi-threaded programming tools as class abstractions. Even if the
basic programming paradigm is non class oriented, the availability of the MutEx,
Semaphore and Condition tools in a class instance can still be used.
-This project will compile to a dynamically loaded library that can be used when
developing multi-threaded applications in C++. The pthreadcc library is based
on the existing pthread library available in most UNIX installations. The
library defines a series of classes that can be used to implement a range of
thread based tools as well as a class that represents an extra thread. This
class library was developed by Jason But at Monash University
Platform: |
Size: 16384 |
Author:李东 |
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Description: Implement semaphore with mutex and conditional variable. Reason being, POSIX semaphore on Android are not used or well tested.
Platform: |
Size: 1024 |
Author:vongkingdang |
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Description: This code implement semaphore, using 2 proccess, which first is write string consanant values to txt-file, second read txt-file-This code implement semaphore, using 2 proccess, which first is write string consanant values to txt-file, second read txt-file Platform: |
Size: 16384 |
Author:Nurba |
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Search - implement semaphore