model: schedule appropriate fence backtracking points
[c11tester.git] / datarace.cc
index d6e0875c1a5562315b26367a3582452d5c41b07d..1ec43be4e8cb72dc246782635fd6497ac8e6ffb3 100644 (file)
@@ -1,35 +1,55 @@
 #include "datarace.h"
 #include "model.h"
-#include "threads.h"
+#include "threads-model.h"
 #include <stdio.h>
 #include <cstring>
 #include "mymemory.h"
 #include "clockvector.h"
+#include "config.h"
+#include "action.h"
 
 struct ShadowTable *root;
 std::vector<struct DataRace *> unrealizedraces;
+void *memory_base;
+void *memory_top;
+
 
 /** This function initialized the data race detector. */
-void initRaceDetector() {
+void initRaceDetector()
+{
        root = (struct ShadowTable *)snapshot_calloc(sizeof(struct ShadowTable), 1);
+       memory_base = snapshot_calloc(sizeof(struct ShadowBaseTable) * SHADOWBASETABLES, 1);
+       memory_top = ((char *)memory_base) + sizeof(struct ShadowBaseTable) * SHADOWBASETABLES;
+}
+
+void * table_calloc(size_t size)
+{
+       if ((((char *)memory_base) + size) > memory_top) {
+               return snapshot_calloc(size, 1);
+       } else {
+               void *tmp = memory_base;
+               memory_base = ((char *)memory_base) + size;
+               return tmp;
+       }
 }
 
 /** 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;
+static uint64_t * lookupAddressEntry(const void *address)
+{
+       struct ShadowTable *currtable = root;
 #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] = snapshot_calloc(sizeof(struct ShadowTable), 1));
+       currtable = (struct ShadowTable *) currtable->array[(((uintptr_t)address) >> 32) & MASK16BIT];
+       if (currtable == NULL) {
+               currtable = (struct ShadowTable *)(root->array[(((uintptr_t)address) >> 32) & MASK16BIT] = table_calloc(sizeof(struct ShadowTable)));
        }
 #endif
 
-       struct ShadowBaseTable * basetable=(struct ShadowBaseTable *) currtable->array[(((uintptr_t)address)>>16)&MASK16BIT];
-       if (basetable==NULL) {
-               basetable = (struct ShadowBaseTable *)(currtable->array[(((uintptr_t)address)>>16)&MASK16BIT] = snapshot_calloc(sizeof(struct ShadowBaseTable), 1));
+       struct ShadowBaseTable *basetable = (struct ShadowBaseTable *)currtable->array[(((uintptr_t)address) >> 16) & MASK16BIT];
+       if (basetable == NULL) {
+               basetable = (struct ShadowBaseTable *)(currtable->array[(((uintptr_t)address) >> 16) & MASK16BIT] = table_calloc(sizeof(struct ShadowBaseTable)));
        }
-       return &basetable->array[((uintptr_t)address)&MASK16BIT];
+       return &basetable->array[((uintptr_t)address) & MASK16BIT];
 }
 
 /**
@@ -51,8 +71,9 @@ static bool clock_may_race(ClockVector *clock1, thread_id_t tid1,
  * 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;
+static void expandRecord(uint64_t *shadow)
+{
+       uint64_t shadowval = *shadow;
 
        modelclock_t readClock = READVECTOR(shadowval);
        thread_id_t readThread = int_to_id(RDTHREADID(shadowval));
@@ -60,80 +81,95 @@ static void expandRecord(uint64_t * shadow) {
        thread_id_t writeThread = int_to_id(WRTHREADID(shadowval));
 
        struct RaceRecord *record = (struct RaceRecord *)snapshot_calloc(1, sizeof(struct RaceRecord));
-       record->writeThread=writeThread;
-       record->writeClock=writeClock;
-
-       if (readClock!=0) {
-               record->capacity=INITCAPACITY;
-               record->thread = (thread_id_t *)snapshot_malloc(sizeof(thread_id_t)*record->capacity);
-               record->readClock = (modelclock_t *)snapshot_malloc(sizeof(modelclock_t)*record->capacity);
-               record->numReads=1;
-               record->thread[0]=readThread;
-               record->readClock[0]=readClock;
+       record->writeThread = writeThread;
+       record->writeClock = writeClock;
+
+       if (readClock != 0) {
+               record->capacity = INITCAPACITY;
+               record->thread = (thread_id_t *)snapshot_malloc(sizeof(thread_id_t) * record->capacity);
+               record->readClock = (modelclock_t *)snapshot_malloc(sizeof(modelclock_t) * record->capacity);
+               record->numReads = 1;
+               record->thread[0] = readThread;
+               record->readClock[0] = readClock;
        }
-       *shadow=(uint64_t) record;
+       *shadow = (uint64_t) record;
 }
 
 /** 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) {
+static void reportDataRace(thread_id_t oldthread, modelclock_t oldclock, bool isoldwrite, ModelAction *newaction, bool isnewwrite, const void *address)
+{
        struct DataRace *race = (struct DataRace *)snapshot_malloc(sizeof(struct DataRace));
-       race->oldthread=oldthread;
-       race->oldclock=oldclock;
-       race->isoldwrite=isoldwrite;
-       race->newaction=newaction;
-       race->isnewwrite=isnewwrite;
-       race->address=address;
+       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();
+       if (checkDataRaces())
                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() {
+/**
+ * @brief Check and report data races
+ *
+ * If the trace is feasible (a feasible prefix), clear out the list of
+ * unrealized data races, asserting any realized ones as execution bugs so that
+ * the model-checker will end the execution.
+ *
+ * @return True if any data races were realized
+ */
+bool checkDataRaces()
+{
        if (model->isfeasibleprefix()) {
+               bool race_asserted = false;
                /* Prune the non-racing unrealized dataraces */
-               unsigned int i,newloc=0;
-               for(i=0;i<unrealizedraces.size();i++) {
-                       struct DataRace * race=unrealizedraces[i];
+               for (unsigned i = 0; i < unrealizedraces.size(); i++) {
+                       struct DataRace *race = unrealizedraces[i];
                        if (clock_may_race(race->newaction->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;i<unrealizedraces.size();i++) {
-                               struct DataRace * race=unrealizedraces[i];
-                               printRace(race);
+                               assert_race(race);
+                               race_asserted = true;
                        }
-                       return true;
+                       snapshot_free(race);
                }
+               unrealizedraces.clear();
+               return race_asserted;
        }
        return false;
 }
 
-void printRace(struct DataRace * race) {
-       printf("Datarace detected\n");
-       printf("Location %p\n", race->address);
-       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);
+/**
+ * @brief Assert a data race
+ *
+ * Asserts a data race which is currently realized, causing the execution to
+ * end and stashing a message in the model-checker's bug list
+ *
+ * @param race The race to report
+ */
+void assert_race(struct DataRace *race)
+{
+       char buf[200];
+       char *ptr = buf;
+       ptr += sprintf(ptr, "Data race detected @ address %p:\n", race->address);
+       ptr += sprintf(ptr, "    Access 1: %5s in thread %2d @ clock %3u\n",
+                       race->isoldwrite ? "write" : "read",
+                       id_to_int(race->oldthread), race->oldclock);
+       ptr += sprintf(ptr, "    Access 2: %5s in thread %2d @ clock %3u",
+                       race->isnewwrite ? "write" : "read",
+                       id_to_int(race->newaction->get_tid()), race->newaction->get_seq_number());
+       model->assert_bug(buf);
 }
 
 /** 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);
+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. */
 
-       for(int i=0;i<record->numReads;i++) {
+       for (int i = 0; i < record->numReads; i++) {
                modelclock_t readClock = record->readClock[i];
                thread_id_t readThread = record->thread[i];
 
@@ -156,19 +192,20 @@ void fullRaceCheckWrite(thread_id_t thread, void *location, uint64_t * shadow, C
                reportDataRace(writeThread, writeClock, true, model->get_parent_action(thread), true, location);
        }
 
-       record->numReads=0;
-       record->writeThread=thread;
+       record->numReads = 0;
+       record->writeThread = thread;
        modelclock_t ourClock = currClock->getClock(thread);
-       record->writeClock=ourClock;
+       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;
+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)) {
+       if (shadowval != 0 && !ISSHORTRECORD(shadowval)) {
                fullRaceCheckWrite(thread, location, shadow, currClock);
                return;
        }
@@ -206,8 +243,9 @@ void raceCheckWrite(thread_id_t thread, void *location, 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);
+void fullRaceCheckRead(thread_id_t thread, const void *location, uint64_t *shadow, ClockVector *currClock)
+{
+       struct RaceRecord *record = (struct RaceRecord *) (*shadow);
 
        /* Check for datarace against last write. */
 
@@ -221,9 +259,9 @@ void fullRaceCheckRead(thread_id_t thread, void *location, uint64_t * shadow, Cl
 
        /* Shorten vector when possible */
 
-       int copytoindex=0;
+       int copytoindex = 0;
 
-       for(int i=0;i<record->numReads;i++) {
+       for (int i = 0; i < record->numReads; i++) {
                modelclock_t readClock = record->readClock[i];
                thread_id_t readThread = record->thread[i];
 
@@ -235,41 +273,42 @@ void fullRaceCheckRead(thread_id_t thread, void *location, uint64_t * shadow, Cl
 
                if (clock_may_race(currClock, thread, readClock, readThread)) {
                        /* Still need this read in vector */
-                       if (copytoindex!=i) {
-                               record->readClock[copytoindex]=record->readClock[i];
-                               record->thread[copytoindex]=record->thread[i];
+                       if (copytoindex != i) {
+                               record->readClock[copytoindex] = record->readClock[i];
+                               record->thread[copytoindex] = record->thread[i];
                        }
                        copytoindex++;
                }
        }
 
-       if (copytoindex>=record->capacity) {
-               int newCapacity=record->capacity*2;
-               thread_id_t *newthread = (thread_id_t *)snapshot_malloc(sizeof(thread_id_t)*newCapacity);
-               modelclock_t *newreadClock =( modelclock_t *)snapshot_malloc(sizeof(modelclock_t)*newCapacity);
-               std::memcpy(newthread, record->thread, record->capacity*sizeof(thread_id_t));
-               std::memcpy(newreadClock, record->readClock, record->capacity*sizeof(modelclock_t));
+       if (copytoindex >= record->capacity) {
+               int newCapacity = record->capacity * 2;
+               thread_id_t *newthread = (thread_id_t *)snapshot_malloc(sizeof(thread_id_t) * newCapacity);
+               modelclock_t *newreadClock = (modelclock_t *)snapshot_malloc(sizeof(modelclock_t) * newCapacity);
+               std::memcpy(newthread, record->thread, record->capacity * sizeof(thread_id_t));
+               std::memcpy(newreadClock, record->readClock, record->capacity * sizeof(modelclock_t));
                snapshot_free(record->readClock);
                snapshot_free(record->thread);
-               record->readClock=newreadClock;
-               record->thread=newthread;
-               record->capacity=newCapacity;
+               record->readClock = newreadClock;
+               record->thread = newthread;
+               record->capacity = newCapacity;
        }
 
        modelclock_t ourClock = currClock->getClock(thread);
 
-       record->thread[copytoindex]=thread;
-       record->readClock[copytoindex]=ourClock;
-       record->numReads=copytoindex+1;
+       record->thread[copytoindex] = thread;
+       record->readClock[copytoindex] = ourClock;
+       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;
+void raceCheckRead(thread_id_t thread, const void *location, ClockVector *currClock)
+{
+       uint64_t *shadow = lookupAddressEntry(location);
+       uint64_t shadowval = *shadow;
 
        /* Do full record */
-       if (shadowval!=0&&!ISSHORTRECORD(shadowval)) {
+       if (shadowval != 0 && !ISSHORTRECORD(shadowval)) {
                fullRaceCheckRead(thread, location, shadow, currClock);
                return;
        }