#include <signal.h>
#include <stdlib.h>
#include <map>
-#include <set>
#include <cstring>
#include <cstdio>
#include "snapshot.h"
#include <errno.h>
#include <sys/wait.h>
#include <ucontext.h>
-#include <sys/time.h>
+
//extern declaration definition
-#define FAILURE(mesg) { printf("failed in the API: %s with errno relative message: %s\n", mesg, strerror( errno ) ); exit( -1 ); }
-#if USE_CHECKPOINTING
+#define FAILURE(mesg) { printf("failed in the API: %s with errno relative message: %s\n", mesg, strerror( errno ) ); exit(EXIT_FAILURE); }
+#if USE_MPROTECT_SNAPSHOT
struct SnapShot * snapshotrecord = NULL;
struct Snapshot_t * sTheRecord = NULL;
#else
struct Snapshot_t * sTheRecord = NULL;
#endif
-void BeginOperation( struct timeval * theStartTime ){
-#if 1
- gettimeofday( theStartTime, NULL );
-#endif
-}
-#if SSDEBUG
-struct timeval *starttime = NULL;
-#endif
void DumpIntoLog( const char * filename, const char * message ){
#if SSDEBUG
static pid_t thePID = getpid();
char newFn[ 1024 ] ={ 0 };
sprintf( newFn,"%s-%d.txt", filename, thePID );
FILE * myFile = fopen( newFn, "w+" );
- struct timeval theEndTime;
- BeginOperation( &theEndTime );
- double elapsed = ( theEndTime.tv_sec - starttime->tv_sec ) + ( theEndTime.tv_usec - starttime->tv_usec ) / 1000000.0;
- fprintf( myFile, "The timestamp %f:--> the message %s: the process id %d\n", elapsed, message, thePID );
+ fprintf( myFile, "the message %s: the process id %d\n", message, thePID );
fflush( myFile );
fclose( myFile );
myFile = NULL;
#endif
}
-#if !USE_CHECKPOINTING
+#if !USE_MPROTECT_SNAPSHOT
static ucontext_t savedSnapshotContext;
static ucontext_t savedUserSnapshotContext;
-static int snapshotid = 0;
+static snapshot_id snapshotid = 0;
#endif
/* Initialize snapshot data structure */
-#if USE_CHECKPOINTING
+#if USE_MPROTECT_SNAPSHOT
void initSnapShotRecord(unsigned int numbackingpages, unsigned int numsnapshots, unsigned int nummemoryregions) {
snapshotrecord=( struct SnapShot * )MYMALLOC(sizeof(struct SnapShot));
snapshotrecord->regionsToSnapShot=( struct MemoryRegion * )MYMALLOC(sizeof(struct MemoryRegion)*nummemoryregions);
#endif //nothing to initialize for the fork based snapshotting.
void HandlePF( int sig, siginfo_t *si, void * unused){
-#if USE_CHECKPOINTING
+#if USE_MPROTECT_SNAPSHOT
if( si->si_code == SEGV_MAPERR ){
- printf("Real Fault at %llx\n", ( long long )si->si_addr);
- exit( EXIT_FAILURE );
+ printf("Real Fault at %p\n", si->si_addr);
+ exit( EXIT_FAILURE );
}
void* addr = ReturnPageAlignedAddress(si->si_addr);
unsigned int backingpage=snapshotrecord->lastBackingPage++; //Could run out of pages...
if (backingpage==snapshotrecord->maxBackingPages) {
- printf("Out of backing pages at %llx\n", ( long long )si->si_addr);
- exit( EXIT_FAILURE );
+ printf("Out of backing pages at %p\n", si->si_addr);
+ exit( EXIT_FAILURE );
}
//copy page
extern "C" {
#endif
void createSharedLibrary(){
-#if !USE_CHECKPOINTING
+#if !USE_MPROTECT_SNAPSHOT
//step 1. create shared memory.
if( sTheRecord ) return;
int fd = shm_open( "/ModelChecker-Snapshotter", O_RDWR | O_CREAT, 0777 ); //universal permissions.
sTheRecord->mStackSize = STACK_SIZE_DEFAULT;
sTheRecord->mIDToRollback = -1;
sTheRecord->currSnapShotID = 0;
+ sTheRecord->mbFinalize = false;
#endif
}
#ifdef __cplusplus
}
#endif
-void initSnapShotLibrary(unsigned int numbackingpages, unsigned int numsnapshots, unsigned int nummemoryregions, unsigned int numheappages, MyFuncPtr entryPoint){
-#if USE_CHECKPOINTING
+void initSnapShotLibrary(unsigned int numbackingpages,
+ unsigned int numsnapshots, unsigned int nummemoryregions,
+ unsigned int numheappages, VoidFuncPtr entryPoint) {
+#if USE_MPROTECT_SNAPSHOT
+ /* Setup a stack for our signal handler.... */
+ stack_t ss;
+ ss.ss_sp = MYMALLOC(SIGSTACKSIZE);
+ ss.ss_size = SIGSTACKSIZE;
+ ss.ss_flags = 0;
+ sigaltstack(&ss, NULL);
+
struct sigaction sa;
- sa.sa_flags = SA_SIGINFO | SA_NODEFER | SA_RESTART;
+ sa.sa_flags = SA_SIGINFO | SA_NODEFER | SA_RESTART | SA_ONSTACK;
sigemptyset( &sa.sa_mask );
sa.sa_sigaction = HandlePF;
+#ifdef MAC
+ if( sigaction( SIGBUS, &sa, NULL ) == -1 ){
+ printf("SIGACTION CANNOT BE INSTALLED\n");
+ exit(EXIT_FAILURE);
+ }
+#endif
if( sigaction( SIGSEGV, &sa, NULL ) == -1 ){
printf("SIGACTION CANNOT BE INSTALLED\n");
- exit(-1);
+ exit(EXIT_FAILURE);
}
+
initSnapShotRecord(numbackingpages, numsnapshots, nummemoryregions);
-
+
+ // EVIL HACK: We need to make sure that calls into the HandlePF method don't cause dynamic links
+ // The problem is that we end up protecting state in the dynamic linker...
+ // Solution is to call our signal handler before we start protecting stuff...
+
+ siginfo_t si;
+ si.si_addr=ss.ss_sp;
+ HandlePF(SIGSEGV, &si, NULL);
+ snapshotrecord->lastBackingPage--; //remove the fake page we copied
+
basemySpace=MYMALLOC((numheappages+1)*PAGESIZE);
void * pagealignedbase=PageAlignAddressUpward(basemySpace);
mySpace = create_mspace_with_base(pagealignedbase, numheappages*PAGESIZE, 1 );
addMemoryRegionToSnapShot(pagealignedbase, numheappages);
entryPoint();
#else
- //add a signal to indicate that the process is going to terminate.
- struct sigaction sa;
- sa.sa_flags = SA_SIGINFO | SA_NODEFER | SA_RESTART;
- sigemptyset( &sa.sa_mask );
- sa.sa_sigaction = HandlePF;
- if( sigaction( SIGUSR1, &sa, NULL ) == -1 ){
- printf("SIGACTION CANNOT BE INSTALLED\n");
- exit(-1);
- }
+
+ basemySpace=system_malloc((numheappages+1)*PAGESIZE);
+ void * pagealignedbase=PageAlignAddressUpward(basemySpace);
+ mySpace = create_mspace_with_base(pagealignedbase, numheappages*PAGESIZE, 1 );
createSharedLibrary();
-#if SSDEBUG
- starttime = &(sTheRecord->startTimeGlobal);
- gettimeofday( starttime, NULL );
-#endif
+
//step 2 setup the stack context.
-
+
int alreadySwapped = 0;
getcontext( &savedSnapshotContext );
if( !alreadySwapped ){
makecontext( &newContext, entryPoint, 0 );
swapcontext( &swappedContext, &newContext );
}
-
+
//add the code to take a snapshot here...
//to return to user process, do a second swapcontext...
pid_t forkedID = 0;
while( !sTheRecord->mbFinalize ){
sTheRecord->currSnapShotID=snapshotid+1;
forkedID = fork();
- if( 0 == forkedID ){
+ if( 0 == forkedID ){
ucontext_t currentContext;
#if 0
int dbg = 0;
if( swapContext )
swapcontext( ¤tContext, &( sTheRecord->mContextToRollback ) );
else{
- swapcontext( ¤tContext, &savedUserSnapshotContext );
+ swapcontext( ¤tContext, &savedUserSnapshotContext );
}
} else {
int status;
sprintf( mesg, "The process id of child is %d and the process id of this process is %d and snapshot id is %d", forkedID, getpid(), snapshotid );
DumpIntoLog( "ModelSnapshot", mesg );
#endif
- do {
+ do {
retVal=waitpid( forkedID, &status, 0 );
} while( -1 == retVal && errno == EINTR );
if( sTheRecord->mIDToRollback != snapshotid )
- exit(0);
+ exit(EXIT_SUCCESS);
else{
swapContext = true;
}
}
}
-
+
#endif
}
/* This function assumes that addr is page aligned */
void addMemoryRegionToSnapShot( void * addr, unsigned int numPages) {
-#if USE_CHECKPOINTING
+#if USE_MPROTECT_SNAPSHOT
unsigned int memoryregion=snapshotrecord->lastRegion++;
if (memoryregion==snapshotrecord->maxRegions) {
printf("Exceeded supported number of memory regions!\n");
- exit(-1);
+ exit(EXIT_FAILURE);
}
-
+
snapshotrecord->regionsToSnapShot[ memoryregion ].basePtr=addr;
snapshotrecord->regionsToSnapShot[ memoryregion ].sizeInPages=numPages;
#endif //NOT REQUIRED IN THE CASE OF FORK BASED SNAPSHOTS.
}
//take snapshot
snapshot_id takeSnapshot( ){
-#if USE_CHECKPOINTING
+#if USE_MPROTECT_SNAPSHOT
for(unsigned int region=0; region<snapshotrecord->lastRegion;region++) {
if( mprotect(snapshotrecord->regionsToSnapShot[region].basePtr, snapshotrecord->regionsToSnapShot[region].sizeInPages*sizeof(struct SnapShotPage), PROT_READ ) == -1 ){
perror("mprotect");
printf("Failed to mprotect inside of takeSnapShot\n");
- exit(-1);
- }
+ exit(EXIT_FAILURE);
+ }
}
unsigned int snapshot=snapshotrecord->lastSnapShot++;
if (snapshot==snapshotrecord->maxSnapShots) {
printf("Out of snapshots\n");
- exit(-1);
+ exit(EXIT_FAILURE);
}
snapshotrecord->snapShots[snapshot].firstBackingPage=snapshotrecord->lastBackingPage;
-
+
return snapshot;
#else
swapcontext( &savedUserSnapshotContext, &savedSnapshotContext );
#endif
}
void rollBack( snapshot_id theID ){
-#if USE_CHECKPOINTING
+#if USE_MPROTECT_SNAPSHOT
std::map< void *, bool, std::less< void * >, MyAlloc< std::pair< const void *, bool > > > duplicateMap;
for(unsigned int region=0; region<snapshotrecord->lastRegion;region++) {
if( mprotect(snapshotrecord->regionsToSnapShot[region].basePtr, snapshotrecord->regionsToSnapShot[region].sizeInPages*sizeof(struct SnapShotPage), PROT_READ | PROT_WRITE ) == -1 ){
perror("mprotect");
printf("Failed to mprotect inside of takeSnapShot\n");
- exit(-1);
- }
+ exit(EXIT_FAILURE);
+ }
}
for(unsigned int page=snapshotrecord->snapShots[theID].firstBackingPage; page<snapshotrecord->lastBackingPage; page++) {
bool oldVal = false;
if( duplicateMap.find( snapshotrecord->backingRecords[page].basePtrOfPage ) != duplicateMap.end() ){
- oldVal = true;
+ oldVal = true;
}
else{
- duplicateMap[ snapshotrecord->backingRecords[page].basePtrOfPage ] = true;
+ duplicateMap[ snapshotrecord->backingRecords[page].basePtrOfPage ] = true;
}
if( !oldVal ){
memcpy(snapshotrecord->backingRecords[page].basePtrOfPage, &snapshotrecord->backingStore[page], sizeof(struct SnapShotPage));
if( !sTemp ){
sTemp = 1;
#if SSDEBUG
- DumpIntoLog( "ModelSnapshot", "Invoked rollback" );
+ DumpIntoLog( "ModelSnapshot", "Invoked rollback" );
#endif
- exit( 0 );
+ exit(EXIT_SUCCESS);
}
#endif
}
void finalize(){
-#if !USE_CHECKPOINTING
+#if !USE_MPROTECT_SNAPSHOT
sTheRecord->mbFinalize = true;
#endif
}
projects / c11tester.git / blobdiff