X-Git-Url: http://plrg.eecs.uci.edu/git/?p=model-checker.git;a=blobdiff_plain;f=datarace.cc;h=1cc407bb991889545210f54ec313ae84c49cf412;hp=da9a3fc15c9716a5a0ec7320bf23bccfb5445ef1;hb=f82a95581e303d67ea57de4ae9e888be10558866;hpb=bcb3a311780c22c8a344c1288f1dd883b7b1960a diff --git a/datarace.cc b/datarace.cc index da9a3fc..1cc407b 100644 --- a/datarace.cc +++ b/datarace.cc @@ -1,18 +1,23 @@ #include "datarace.h" +#include "model.h" #include "threads.h" #include #include struct ShadowTable *root; +std::vector unrealizedraces; +/** This function initialized the data race detector. */ void initRaceDetector() { root=(struct ShadowTable *) calloc(sizeof(struct ShadowTable),1); } +/** This function looks up the entry in the shadow table corresponding to a + * given address.*/ static uint64_t * lookupAddressEntry(void * address) { struct ShadowTable *currtable=root; -#ifdef BIT48 - currtable=(struct ShadowTable *) currtable->array[(((uintptr_t)address)>>32)&0xffff]; +#if BIT48 + currtable=(struct ShadowTable *) currtable->array[(((uintptr_t)address)>>32)&MASK16BIT]; if (currtable==NULL) { currtable=(struct ShadowTable *) (root->array[(((uintptr_t)address)>>32)&MASK16BIT]=calloc(sizeof(struct ShadowTable),1)); } @@ -25,6 +30,25 @@ static uint64_t * lookupAddressEntry(void * address) { return &basetable->array[((uintptr_t)address)&MASK16BIT]; } +/** + * Compares a current clock-vector/thread-ID pair with a clock/thread-ID pair + * to check the potential for a data race. + * @param clock1 The current clock vector + * @param tid1 The current thread; paired with clock1 + * @param clock2 The clock value for the potentially-racing action + * @param tid2 The thread ID for the potentially-racing action + * @return true if the current clock allows a race with the event at clock2/tid2 + */ +static bool clock_may_race(ClockVector *clock1, thread_id_t tid1, + modelclock_t clock2, thread_id_t tid2) +{ + return tid1 != tid2 && clock2 != 0 && clock1->getClock(tid2) <= clock2; +} + +/** + * Expands a record from the compact form to the full form. This is + * necessary for multiple readers or for very large thread ids or time + * stamps. */ static void expandRecord(uint64_t * shadow) { uint64_t shadowval=*shadow; @@ -48,11 +72,61 @@ static void expandRecord(uint64_t * shadow) { *shadow=(uint64_t) record; } -static void reportDataRace() { - printf("The reportDataRace method should report useful things about this datarace!\n"); +/** This function is called when we detect a data race.*/ +static void reportDataRace(thread_id_t oldthread, modelclock_t oldclock, bool isoldwrite, ModelAction *newaction, bool isnewwrite, void *address) { + struct DataRace * race=(struct DataRace *)malloc(sizeof(struct DataRace)); + race->oldthread=oldthread; + race->oldclock=oldclock; + race->isoldwrite=isoldwrite; + race->newaction=newaction; + race->isnewwrite=isnewwrite; + race->address=address; + unrealizedraces.push_back(race); + + /* If the race is realized, bail out now. */ + if (checkDataRaces()) { + model->set_assert(); + model->switch_to_master(NULL); + } +} + +/** This function goes through the list of unrealized data races, + * removes the impossible ones, and print the realized ones. */ + +bool checkDataRaces() { + if (model->isfeasibleprefix()) { + /* Prune the non-racing unrealized dataraces */ + unsigned int i,newloc=0; + for(i=0;inewaction->get_cv(), race->newaction->get_tid(), race->oldclock, race->oldthread)) { + unrealizedraces[newloc++]=race; + } + } + if (newloc!=i) + unrealizedraces.resize(newloc); + + if (unrealizedraces.size()!=0) { + /* We have an actual realized race. */ + for(i=0;iaddress); + printf("Initial access: thread %u clock %u, iswrite %u\n",race->oldthread,race->oldclock, race->isoldwrite); + printf("Second access: thread %u clock %u, iswrite %u\n", race->newaction->get_tid(), race->newaction->get_seq_number() , race->isnewwrite); } -void fullRaceCheckWrite(thread_id_t thread, uint64_t * shadow, ClockVector *currClock) { +/** This function does race detection for a write on an expanded record. */ +void fullRaceCheckWrite(thread_id_t thread, void *location, uint64_t * shadow, ClockVector *currClock) { struct RaceRecord * record=(struct RaceRecord *) (*shadow); /* Check for datarace against last read. */ @@ -61,9 +135,12 @@ void fullRaceCheckWrite(thread_id_t thread, uint64_t * shadow, ClockVector *curr modelclock_t readClock = record->readClock[i]; thread_id_t readThread = record->thread[i]; - if (readThread != thread && readClock != 0 && currClock->getClock(readThread) <= readClock) { + /* Note that readClock can't actuall be zero here, so it could be + optimized. */ + + if (clock_may_race(currClock, thread, readClock, readThread)) { /* We have a datarace */ - reportDataRace(); + reportDataRace(readThread, readClock, false, model->get_parent_action(thread), true, location); } } @@ -72,9 +149,9 @@ void fullRaceCheckWrite(thread_id_t thread, uint64_t * shadow, ClockVector *curr modelclock_t writeClock = record->writeClock; thread_id_t writeThread = record->writeThread; - if (writeThread != thread && writeClock != 0 && currClock->getClock(writeThread) <= writeClock) { + if (clock_may_race(currClock, thread, writeClock, writeThread)) { /* We have a datarace */ - reportDataRace(); + reportDataRace(writeThread, writeClock, true, model->get_parent_action(thread), true, location); } record->numReads=0; @@ -83,13 +160,14 @@ void fullRaceCheckWrite(thread_id_t thread, uint64_t * shadow, ClockVector *curr record->writeClock=ourClock; } +/** This function does race detection on a write. */ void raceCheckWrite(thread_id_t thread, void *location, ClockVector *currClock) { uint64_t * shadow=lookupAddressEntry(location); uint64_t shadowval=*shadow; /* Do full record */ if (shadowval!=0&&!ISSHORTRECORD(shadowval)) { - fullRaceCheckWrite(thread, shadow, currClock); + fullRaceCheckWrite(thread, location, shadow, currClock); return; } @@ -99,7 +177,7 @@ void raceCheckWrite(thread_id_t thread, void *location, ClockVector *currClock) /* Thread ID is too large or clock is too large. */ if (threadid > MAXTHREADID || ourClock > MAXWRITEVECTOR) { expandRecord(shadow); - fullRaceCheckWrite(thread, shadow, currClock); + fullRaceCheckWrite(thread, location, shadow, currClock); return; } @@ -108,9 +186,9 @@ void raceCheckWrite(thread_id_t thread, void *location, ClockVector *currClock) modelclock_t readClock = READVECTOR(shadowval); thread_id_t readThread = int_to_id(RDTHREADID(shadowval)); - if (readThread != thread && readClock != 0 && currClock->getClock(readThread) <= readClock) { + if (clock_may_race(currClock, thread, readClock, readThread)) { /* We have a datarace */ - reportDataRace(); + reportDataRace(readThread, readClock, false, model->get_parent_action(thread), true, location); } /* Check for datarace against last write. */ @@ -118,14 +196,15 @@ void raceCheckWrite(thread_id_t thread, void *location, ClockVector *currClock) modelclock_t writeClock = WRITEVECTOR(shadowval); thread_id_t writeThread = int_to_id(WRTHREADID(shadowval)); - if (writeThread != thread && writeClock != 0 && currClock->getClock(writeThread) <= writeClock) { + if (clock_may_race(currClock, thread, writeClock, writeThread)) { /* We have a datarace */ - reportDataRace(); + reportDataRace(writeThread, writeClock, true, model->get_parent_action(thread), true, location); } *shadow = ENCODEOP(0, 0, threadid, ourClock); } -void fullRaceCheckRead(thread_id_t thread, uint64_t * shadow, ClockVector *currClock) { +/** This function does race detection on a read for an expanded record. */ +void fullRaceCheckRead(thread_id_t thread, void *location, uint64_t * shadow, ClockVector *currClock) { struct RaceRecord * record=(struct RaceRecord *) (*shadow); /* Check for datarace against last write. */ @@ -133,9 +212,9 @@ void fullRaceCheckRead(thread_id_t thread, uint64_t * shadow, ClockVector *currC modelclock_t writeClock = record->writeClock; thread_id_t writeThread = record->writeThread; - if (writeThread != thread && writeClock != 0 && currClock->getClock(writeThread) <= writeClock) { + if (clock_may_race(currClock, thread, writeClock, writeThread)) { /* We have a datarace */ - reportDataRace(); + reportDataRace(writeThread, writeClock, true, model->get_parent_action(thread), false, location); } /* Shorten vector when possible */ @@ -146,7 +225,13 @@ void fullRaceCheckRead(thread_id_t thread, uint64_t * shadow, ClockVector *currC modelclock_t readClock = record->readClock[i]; thread_id_t readThread = record->thread[i]; - if (readThread != thread && currClock->getClock(readThread) <= readClock) { + /* Note that is not really a datarace check as reads cannott + actually race. It is just determining that this read subsumes + another in the sense that either this read races or neither + read races. Note that readClock can't actually be zero, so it + could be optimized. */ + + if (clock_may_race(currClock, thread, readClock, readThread)) { /* Still need this read in vector */ if (copytoindex!=i) { record->readClock[copytoindex]=record->readClock[i]; @@ -176,13 +261,14 @@ void fullRaceCheckRead(thread_id_t thread, uint64_t * shadow, ClockVector *currC record->numReads=copytoindex+1; } +/** This function does race detection on a read. */ void raceCheckRead(thread_id_t thread, void *location, ClockVector *currClock) { uint64_t * shadow=lookupAddressEntry(location); uint64_t shadowval=*shadow; /* Do full record */ if (shadowval!=0&&!ISSHORTRECORD(shadowval)) { - fullRaceCheckRead(thread, shadow, currClock); + fullRaceCheckRead(thread, location, shadow, currClock); return; } @@ -192,7 +278,7 @@ void raceCheckRead(thread_id_t thread, void *location, ClockVector *currClock) { /* Thread ID is too large or clock is too large. */ if (threadid > MAXTHREADID || ourClock > MAXWRITEVECTOR) { expandRecord(shadow); - fullRaceCheckRead(thread, shadow, currClock); + fullRaceCheckRead(thread, location, shadow, currClock); return; } @@ -201,20 +287,20 @@ void raceCheckRead(thread_id_t thread, void *location, ClockVector *currClock) { modelclock_t writeClock = WRITEVECTOR(shadowval); thread_id_t writeThread = int_to_id(WRTHREADID(shadowval)); - if (writeThread != thread && writeClock != 0 && currClock->getClock(writeThread) <= writeClock) { + if (clock_may_race(currClock, thread, writeClock, writeThread)) { /* We have a datarace */ - reportDataRace(); + reportDataRace(writeThread, writeClock, true, model->get_parent_action(thread), false, location); } modelclock_t readClock = READVECTOR(shadowval); thread_id_t readThread = int_to_id(RDTHREADID(shadowval)); - if (readThread != thread && readClock != 0 && currClock->getClock(readThread) <= readClock) { + if (clock_may_race(currClock, thread, readClock, readThread)) { /* We don't subsume this read... Have to expand record. */ expandRecord(shadow); - fullRaceCheckRead(thread, shadow, currClock); + fullRaceCheckRead(thread, location, shadow, currClock); return; } - *shadow = ENCODEOP(writeThread, writeClock, threadid, ourClock); + *shadow = ENCODEOP(threadid, ourClock, id_to_int(writeThread), writeClock); }