| 1. |
- Ermedahl, Andreas
(author)
-
A Modular Tool Architecture for Worst-Case Execution Time Analysis
- 2008
-
Book (other academic/artistic)abstract
- Our society is today extremely dependent oncomputers. Not only PCs and laptops, but also the myriad of computers embedded ineveryday things around us, such as vehicles, aircrafts, toys, and telephones. For many of these computers their correctness depends not onlyon the resultsof their computations, but also on the time at which the results are produced. Failure to produce a result within given timing boundaries may cause substantial economic losses, or evene ndanger humanlife. A worst-case execution time (WCET) analysis derives an upper estimate on the worst possible execution time of a computerprogram. Reliable WCET estimates are a foundation when it must be proven that an embedded system always will behave correctly,even in the most stressful situations. This book contains the dissertation of DrAndreas Ermedahl, a renowned researcher and WCET analysis expert. It presents a WCET tool architecture applicable to a wide spectrum of embedded computers and programs, together with suitable algorithms and data structures. The book should be of interest for anyone involved inembedded system development who wants a deeper understanding of the timing analysis process.
|
|
| 2. |
- Ermedahl, Andreas, et al.
(author)
-
Execution Time Analysis for Embedded Real-Time Systems
- 2007
-
In: Handbook of Real-Time Embedded Systems. - : CRC Press. - 9781420011746 ; , s. 35.1-
-
Book chapter (other academic/artistic)abstract
- Knowing the execution-time characteristics of a program is fundamental to the successful design, validation and deployment of real-time systems. This chapter deals with the problem of how to estimate, measure and analyze the execution time of embedded real-time programs. Of particular interest is the worst-case execution time (WCET). It covers the reasons for program execution time variation, including both the software and hardware complexity inherent in today's embedded systems. It gives an overview of various techniques used to derive execution time estimates. Finally we summarize a number of industrial case-studies of timing analysis, to show how timing analysis works in practice.
|
|
| 3. |
- Gustafsson, Jan, et al.
(author)
-
ALF (ARTIST2 Language for Flow Analysis) Specification
- 2008
-
Reports (other academic/artistic)abstract
- ALF (ARTIST2 Language for Flow Analysis) is a language intended to be used for flow analysis in conjunction with WCET(Worst Case Execution Time) analysis. ALF is designed to be possible to generate from a rich set of sources: linked binaries,source code, compiler intermediate formats, and possibly more.
|
|
| 4. |
- Sundmark, Daniel, et al.
(author)
-
Finding DU-Paths for Testing of Multi-Tasking Real-Time Systems using WCET Analysis
- 2007
-
In: OpenAccess Series in Informatics, Volume 6. - 9783939897057
-
Reports (other academic/artistic)abstract
- Memory corruption is one of the most common software failures. For sequential software and multitasking software with synchronized data accesses, it has been shown that program faults causing memory corruption can be detected by analyzing the relations between defines and uses of variables (DU-based testing). However, such methods are insufficient in preemptive systems, since they lack the ability to detect inter-task shared variable dependencies. In this paper, we propose the use of a system level shared variable DU analysis of preemptive multi-tasking real-time software. By deriving temporal attributes of each access to shared data using WCET analysis, and combining this information with the real-time schedule information, our method also detects inter-task shared variable dependencies
|
|
| 5. |
- Sundmark, Daniel, 1975-
(author)
-
Structural System-Level Testing of Embedded Real-Time Systems
- 2008
-
Doctoral thesis (other academic/artistic)abstract
- People make mistakes. Software engineers are no exception to this fact. When software engineers make mistakes, these manifest in the form of buggy software - a major problem in today's industry. The existence of bugs is commonly detected using testing, the process of executing the software and checking if its behaviour complies with the specification. As limitations in time make testing of the entire software behaviour impracticable, testers need to make informed decisions on how to test the software to detect as many bugs as possible.In the realm of real-time systems (RTSs), software testing is made more difficult by non-deterministic factors such as interaction with the surrounding environment, (pseudo)parallelism, and timing requirements. Furthermore, RTS testing suffers from behaviour-altering perturbation from the instrumentation inserted in the system to keep track of test progress (i.e., probe effects).In our work, we analyse the main test criteria used for traditional software testing in order to see which of these scale to, and assist in, system-level testing of multi-tasking RTSs. We focus on one of these criteria, the all definition-use paths coverage criterion, as it highlights a central aspect of non-deterministic task interaction, and investigate what is specifically required for applying this criterion to testing of multi-tasking RTSs. Further, we examine the possibility of using execution replay for probe effect-free test monitoring. We evaluate this approach in real industrial settings by means of case studies.The contributions of this thesis are twofold: First, the use of structural test criteria in RTS system-level testing is facilitated by two different analysis methods. Second, the probe effect is handled by recording non-deterministic events during run-time, and by using this recording to create a monitorable deterministic replica of the first execution. By these contributions, this thesis shows how the non-determinism of multi-tasking RTSs can be handled during system-level testing.
|
|
