研讨会 任务线程设计.ppt

DSP/BIOS 1 DSP/BIOS System Integration Workshop Objectives Tasks Scheduler States : TSK vs SWI SWI vs. TSK Tasks DSP/BIOS Scheduler Thread Preemption Example Tasks Task Code Topology - SEM Posting Semaphore Pend Semaphore Post Static Creation of SEM SEM API Summary Tasks Static Creation of TSK Task Object Concepts... Task object: Pointer to task function Priority: changable Pointer to task’s stack Stores local variables Nested function calls makes blocking possible Interrupts run on the system stack Pointer to text name of TSK Environment: pointer to user defined structure: TSK Object Tasks TSK API Summary TSK API Summary Tasks Lab 5: Task Thread - TSK Lab 5 : Procedure Overview Lab Details Good tip to point out: SEM_pend() can be called by a SWI if the timeout is 0 – and only in this case. Copyright ? 2004 Texas Instruments. All rights reserved. T TO Technical Training Organization 1 Introduction Real-Time System Design Considerations Hardware Interrupts (HWI) Software Interrupts (SWI) Task Authoring (TSK) Data Streaming (SIO) Multi-Threading (CLK, PRD) BIOS Instrumentation (LOG, STS, SYS, TRC) Static Systems (GCONF, TCONF) Cache (BCACHE) Dynamic Systems (MEM, BUF) Flash Programming (HexAIS, Flashburn) Inter-Thread Communication (MSGQ, ...) DSP Algorithm Standard (XDAIS) Input Output Mini-Drivers (IOM) Direct Memory Access (DMA) Review Describe the fundamental concepts of tasks Demonstrate the use of semaphores in tasks Author TSK code using simple data block pointers Create a TSK with the CCS GUI Describe the TSK object Modify SWI based code to employ TSK T TO Technical Training Organization 2 TSK vs SWI TSK Scheduling Semaphores (SEM) Task Object Review Lab 1 2 Ready Blocked Terminated 1 2 Running pend post preempted Created whenhighestpriority T TO Technical Training Organization 3 SWI TSK 1 2 Ready Blocked Terminated 1 2 Running pend post preempted Created whenhighestpriority 1 2 Ready Inactive 1 2 Running whenhighestpriority preempted Posted Cr