Formal Models of Operating System Kernels phần 7 doc

... message contains the identifier of the sending process. It also contains two natural numbers (elements of N). They denote the size of the data area and the size of the stack area that are, respectively, ... prove some fairly general properties of the message-passing system. Proposition 112. The message-passing mechanism is synchronous. Proof. By the predicates of SendMessage and...

Ngày tải lên: 23/07/2014, 23:20

... 278 haveVictim 274 onPageFault 278 retrievePageFromDisk 276 storePageOnDisk 276 swapPageToDisk 275 PageFaultISR: INIT 272 OnPageInterrupt 272 PageFrames: ClearRefBitsAndCounter 271 ComputeHitCounts 271 GetPage ... 146 Relation: < P 71 = P 71 > P 71 ≥ P 71 ≤ P 71 smap 289 Class: AlarmRQBuffer 182 CLOCKISR 177 , 225 CURRENTPROCESS 78 ClockDriver 183, 225 Context 69,...

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... N pgallocstart =0 The value of 0 is completely arbitrary, as is now explained. Some systems map a virtual copy of the operating system onto the vir- tual address space of each user space (and some ... determine a number of properties of CCS and CSP processes, including observational equivalence and bisimilarity. The propositions concerning equivalence of the various versions...

Ngày tải lên: 23/07/2014, 23:20

... comprising the system- call library all send and receive messages. Therefore, the rest of the proof must be in terms of the properties of the message-passing subsystem. The message-passing subsystem is ... of sharedpages(p)(sg), for some p and sg. Proof. Similar to the previous proof. ✷ Proposition 134. IsLockedPage iff lpno? is a locked page; that is, iff lpno? is an element of lock...

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... most significant aspect of this chapter’s model is that it acts as an existence proof. It is possible to define a formal model of an operating system kernel and to prove some of its properties. In ... of the current kernel. 5.2 Requirements The requirement is to model an operating system kernel that is based upon the exchange of messages between processes. The kernel should...

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... to determine all the children of a parent process. 4.8 General Results This final section contains the proof of a number of propositions that deal with properties of the kernel. The propositions ... an idea of some of the other things that might need to be handled during termination). If a process is on disk when it is terminated (say, because of system ter- mination or because...

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... descendant of the ancestor of the process just blocked. Proof. This requires the proof of the following lemma. Lemma 16. For any process, p, BlockProcessChildren implies that there are no children of ... closure of the childof relation; the complete set of descendants of a given process are represented by childof + (|{p?}|) for any process identifier p?. In BlockProcessChildren,...

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... • parentof (p 1 , p?)) RemoveProcessFromParent ∆(parentof ) parent?, child?:APREF parentof  = parentof \{(parent?, child?)} ParentOfProcess p?:APREF parent!:APREF (∃ p 1 : APREF • parentof (p 1 , ... priority of process, p. If p is an element of q, then MakeUnready[p/pid?] implies that p is not an element of q  . Proof. There are two cases to consider: Case 1. Process p is the head o...

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... performed, the inclusion of IdleProcRef and the ex- clusion of NullProcRef are of some importance. They determine the range of possible values for the domains of the components of process descriptors. ... the idle process, of course. Proof. The components of the process description, pstate, pkind, pstack, pregs, etc., all have identical domains by the first part of the invari...

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... scope for different models is relatively broad. Formal Models of Operating System Kernels x Contents 3.6 Current Process and Prioritised Ready Queue 77 3 .7 MessagesandSemaphoreTables 81 3.8 Process ... the upper layers of an operating system. OS Kit is a software kit, not a formal specification or modelling tool. Iain D. Craig Formal Models of Operating System...

Ngày tải lên: 23/07/2014, 23:20