13th IEEE Real Time and Embedded Technology and Applications Symposium (RTAS'07)最新文献

Dynamic Patching of Embedded Software 嵌入式软件动态补丁

13th IEEE Real Time and Embedded Technology and Applications Symposium (RTAS'07) Pub Date : 2007-04-03 DOI: 10.1109/RTAS.2007.10

M. Ekman, Henrik Thane

引用次数: 12

Hijack: Taking Control of COTS Systems for Real-Time User-Level Services 劫持:为实时用户级服务控制COTS系统

13th IEEE Real Time and Embedded Technology and Applications Symposium (RTAS'07) Pub Date : 2007-04-03 DOI: 10.1109/RTAS.2007.14

Gabriel Parmer, R. West

{"title":"Hijack: Taking Control of COTS Systems for Real-Time User-Level Services","authors":"Gabriel Parmer, R. West","doi":"10.1109/RTAS.2007.14","DOIUrl":"https://doi.org/10.1109/RTAS.2007.14","url":null,"abstract":"This paper focuses on a technique to empower commercial-off-the-shelf (COTS) systems with an execution environment, and corresponding services, to support real-time and embedded applications. By leveraging COTS systems, we are able to reduce the potentially expensive maintenance and development costs of proprietary solutions. We describe a system called \"Hijack\" that enables user-level services to take control of features such as CPU scheduling, interrupt handling and synchronization. In contrast to other approaches that support real-time tasks within the kernel of commodity systems such as Linux, Hijack provides the basis for predictable thread execution at user-level. No changes to the kernel source code are required to support this approach. Instead, Hijack works by using a combination of kernel module support and an interposed execution environment between traditional process address spaces and the kernel. This technique enables system calls and hardware interrupts to be intercepted with bounded latencies via the kernel module, that passes control to a user-level real-time executive. From within the executive, system-wide services and policies can be deployed to over-ride certain features of the underlying kernel, while still leveraging base kernel services where appropriate. Using this technique, we show how a vanilla Linux system can be hijacked to support predictable service execution using a series of user-defined policies. In particular, we show how to deliver and process asynchronous events with bounded latency, using interposition agents within a Hijack execution environment. Results show that for realtime streaming applications, Hijack is able to receive and process packets with significantly lower loss rates and jitter compared to using alternative application-level processes for the same task","PeriodicalId":222543,"journal":{"name":"13th IEEE Real Time and Embedded Technology and Applications Symposium (RTAS'07)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123218812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 26

Optimizing the FPGA Implementation of HRT Systems HRT系统的FPGA实现优化

13th IEEE Real Time and Embedded Technology and Applications Symposium (RTAS'07) Pub Date : 2007-04-03 DOI: 10.1109/RTAS.2007.25

M. Natale, Enrico Bini

引用次数: 8

Soft Real-Time Chains for Multi-Hop Wireless Ad-Hoc Networks 多跳无线自组织网络的软实时链

13th IEEE Real Time and Embedded Technology and Applications Symposium (RTAS'07) Pub Date : 2007-04-03 DOI: 10.1109/RTAS.2007.34

B. D. Bui, R. Pellizzoni, M. Caccamo, C. Cheah, A. Tzakis

引用次数: 38

Optimal Unified Data Allocation and Task Scheduling for Real-Time Multi-Tasking Systems 实时多任务系统的最优统一数据分配和任务调度

13th IEEE Real Time and Embedded Technology and Applications Symposium (RTAS'07) Pub Date : 2007-04-03 DOI: 10.1109/RTAS.2007.23

R. Ghattas, Gregory S. Parsons, A. Dean

{"title":"Optimal Unified Data Allocation and Task Scheduling for Real-Time Multi-Tasking Systems","authors":"R. Ghattas, Gregory S. Parsons, A. Dean","doi":"10.1109/RTAS.2007.23","DOIUrl":"https://doi.org/10.1109/RTAS.2007.23","url":null,"abstract":"Many real-time (RT) embedded systems can benefit from a memory hierarchy to bridge the processor/memory speed gap. These RT embedded systems usually utilize a cacheless architecture to avoid the time variability which complicates the timing analysis essential for RT systems. In the absence of a cache the burden of allocating the data objects to the memory hierarchy is on the programmer/compiler. There has been much research into allocating data objects into the memory hierarchy for efficient execution. However, existing methods have limited scope and ignore some aspects of RT multitasking embedded systems. In this paper we propose a synergistic, optimal approach to allocating data objects and scheduling real-time tasks for embedded systems. We allocate data using integer linear programming (ILP) to minimize each task's worst-case execution time (WCET), then perform preemption threshold scheduling (PTS) on the tasks to reduce stack memory requirements while still meeting hard RT deadlines. The memory reduction of PTS allows these steps to be repeated. The data objects now require less memory, so more can fit into faster memory, further reducing WCET. The increased slack time can be used by PTS to reduce preemptions further, until a fixed point is reached. We evaluate the technique with several levels of data object granularity using both synthetic workloads and a real-time benchmark and find it to be highly effective","PeriodicalId":222543,"journal":{"name":"13th IEEE Real Time and Embedded Technology and Applications Symposium (RTAS'07)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123821987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 13

Dynamic Task Scheduling and Processing Element Allocation for Multi-Function SoCs 多功能soc的动态任务调度与处理单元分配

13th IEEE Real Time and Embedded Technology and Applications Symposium (RTAS'07) Pub Date : 2007-04-03 DOI: 10.1109/RTAS.2007.11

Ya-Shu Chen, C. Shih, Tei-Wei Kuo

引用次数: 9

Prioritized SMT Architecture with IPC Control Method for Real-Time Processing 优先级SMT结构与IPC控制方法的实时处理

13th IEEE Real Time and Embedded Technology and Applications Symposium (RTAS'07) Pub Date : 2007-04-03 DOI: 10.1109/RTAS.2007.28

N. Yamasaki, Ikuo Magaki, T. Itou

{"title":"Prioritized SMT Architecture with IPC Control Method for Real-Time Processing","authors":"N. Yamasaki, Ikuo Magaki, T. Itou","doi":"10.1109/RTAS.2007.28","DOIUrl":"https://doi.org/10.1109/RTAS.2007.28","url":null,"abstract":"This paper describes a novel processor architecture, the prioritized SMT architecture with the IPC control method, to guarantee the execution time of real-time threads. Based on priority set by a real-time scheduler, all hardware resources including cache systems, fetch, issue, and execution units, are controlled, so that our processor can execute multiple threads in real-time. All runnable threads are simultaneously executed as much as possible in priority order, so that the execution order becomes congruent with the priority order set by a real-time scheduler. If a resource conflict occurs, the lower priority threads are kept waiting until the higher priority thread finishes using the resource. In brief, context switching required for real-time scheduling and execution is converted to the prioritized SMT execution. Here, some triggers including cache misses and branch prediction misses fluctuate the execution speed of a thread. Additionally, in case of an SMT processor, the execution time of each thread may vary according to a combination of simultaneous executing threads. To guarantee the execution time of real-time threads accurately, the IPC control method that monitors and controls each thread IPC in a feedback loop is designed and implemented. Our IPC control method can keep the IPC deviation of the thread within plusmn1% bounds, if the target IPC is less than 80% of the single thread execution IPC. Our processor is implemented as a processing core of a system LSI, which process was TSMC 0.13 mum 8 layered Cu wiring, used for distributed real-time systems including humanoid robots, bilateral robots, embedded control systems, and ubiquitous computing systems","PeriodicalId":222543,"journal":{"name":"13th IEEE Real Time and Embedded Technology and Applications Symposium (RTAS'07)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125159326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 32

Real-Time Divisible Load Scheduling for Cluster Computing 面向集群计算的实时可分负载调度

13th IEEE Real Time and Embedded Technology and Applications Symposium (RTAS'07) Pub Date : 2007-04-03 DOI: 10.1109/RTAS.2007.29

Xuan Lin, Ying Lu, J. Deogun, S. Goddard

引用次数: 72

Optimizing End-to-End Latencies by Adaptation of the Activation Events in Distributed Automotive Systems 基于自适应激活事件的分布式汽车系统端到端延迟优化

13th IEEE Real Time and Embedded Technology and Applications Symposium (RTAS'07) Pub Date : 2007-04-03 DOI: 10.1109/RTAS.2007.24

M. Natale, Wei Zheng, C. Pinello, P. Giusto, A. Sangiovanni-Vincentelli

引用次数: 37

Optimal Static Task Scheduling on Reconfigurable Hardware Devices Using Model-Checking 基于模型检查的可重构硬件设备的最优静态任务调度

13th IEEE Real Time and Embedded Technology and Applications Symposium (RTAS'07) Pub Date : 2007-04-03 DOI: 10.1109/RTAS.2007.22

Z. Gu, Mingxuan Yuan, Xiuqiang He

引用次数: 16