formally veriï¬ed deadlock detecon in packet and wormhole networks

Network

Rou+ng

Resourcedependencygraph

Markings

Resourceris:

Deadlock‐sensi+ve

Deadlock‐immune

Deadlock‐a=ainable

Formallyverifieddeadlockdetec+oninpacketandwormholenetworksNWOfreecompe,,on612.064.811

Deadlock‐freerou+ng

Results

Topologies: Mesh/ring Virtualchannels

References

Formalverifica+on

Switchingpolicy Packet Wormhole

Rou+ngfunc+ons: Determinis+c/adap+ve Cyclic/acyclicdependencies

FreekVerbeek,RadboudUniversiteitNijmegen,f.verbeek@cs.ru.nlJulienSchmaltz,OpenUniversiteitNederland,Julien.Schmaltz@ou.nl

Formallyverified: Necessaryandsufficientcondi+ons Correctnessofspecifica+onofalgorithms

 F.VerbeekandJ.Schmaltz.AFastandVerifiedAlgorithmforProvingStore‐and‐ForwardNetworksDeadlock‐Free(PDP'11) ‐‐‐‐.Automa+cverifica+onfordeadlockinnetworks‐on‐chipswithadap+verou+ngandwormholeswitching(NOCS‘11) ‐‐‐‐.OnNecessaryandSufficientCondi3onsforDeadlock‐FreeRou3nginWormholeNetworks(TPDS’11) ‐‐‐‐.ACommenton“ANecessaryandSufficientCondi3onforDeadlock‐FreeAdap3veRou3nginWormholeNetworks”(TPDS‘11)

Algorithms

 Deadlockfreedomisanessen+alpropertyforNetworks‐on‐chips Manualdeadlockdetec+onisextremelyerror‐prone

Switching Complexity Complete Formallyverified

Packet O(N2) Yes YesWormhole O(N3) No Yes

Sourcecodeandproofscripts:h=p://www.cs.ru.nl/~freekver/dl_ic.html

Implementa+onofalgorithmsinC

d0 d1

AB C

E DFB

CE

A

D

F

Example: