/*
* Save current state for block. If this is the first time saving state for
* block, create a new snapshot. Otherwise merge the current state into the
* existing snapshot.
*/
void FrameState::save(Block* block) {
auto it = m_snapshots.find(block);
if (it != m_snapshots.end()) {
merge(it->second);
} else {
auto& snapshot = m_snapshots[block] = createSnapshot();
snapshot.inlineSavedStates = m_inlineSavedStates;
}
}
/*
* Save current state for block. If this is the first time saving state for
* block, create a new snapshot. Otherwise merge the current state into the
* existing snapshot.
*/
void FrameState::save(Block* block) {
FTRACE(4, "Saving state for B{}: {}\n", block->id(), show(*this));
auto it = m_snapshots.find(block);
if (it != m_snapshots.end()) {
merge(it->second);
FTRACE(4, "Merged state: {}\n", show(*this));
} else {
auto& snapshot = m_snapshots[block] = createSnapshot();
snapshot.inlineSavedStates = m_inlineSavedStates;
}
}
void FrameState::trackDefInlineFP(const IRInstruction* inst) {
auto const target = inst->extra<DefInlineFP>()->target;
auto const savedSPOff = inst->extra<DefInlineFP>()->retSPOff;
auto const calleeFP = inst->dst();
auto const calleeSP = inst->src(0);
auto const savedSP = inst->src(1);
// Saved IRBuilder state will include the "return" fp/sp.
// Whatever the current fpValue is is good enough, but we have to be
// passed in the StkPtr that represents the stack prior to the
// ActRec being allocated.
m_spOffset = savedSPOff;
m_spValue = savedSP;
auto const stackValues = collectStackValues(m_spValue, m_spOffset);
for (DEBUG_ONLY auto& val : stackValues) {
FTRACE(4, " marking caller stack value available: {}\n",
val->toString());
}
m_inlineSavedStates.emplace_back(createSnapshot());
/*
* Set up the callee state.
*
* We set m_thisIsAvailable to true on any object method, because we
* just don't inline calls to object methods with a null $this.
*/
m_fpValue = calleeFP;
m_spValue = calleeSP;
m_thisAvailable = target->cls() != nullptr && !target->isStatic();
m_curFunc = target;
m_frameSpansCall = false;
m_locals.clear();
m_locals.resize(target->numLocals());
}
int syncInit(int cfd, long long *tbytes) {
char errmsg[ERRMSG_MAX] = {0};
SyncInit *syncinit;
SyncInitResponse response = SYNC_INIT_RESPONSE__INIT;
syncinit = (SyncInit *) recvMessage(cfd, SyncInitType, tbytes);
if (syncinit == NULL) {
errMsg(LOG_ERR, "Could not read initialization message from client.");
return -1;
}
// initial checks
// check resource (must match)
if (strcmp(syncinit->resource, config.resource) != 0) {
snprintf(errmsg, ERRMSG_MAX, "Received resource %s does not match."
"local resource %s", syncinit->resource, config.resource);
response.continue_ = 0;
response.error_message = errmsg;
sendMessage(cfd, SyncInitResponseType, &response);
return -1;
}
// check sync-id
char lastsyncid[SYNCID_MAX];
char lastsyncidpath[PATH_MAX];
char syncid[SYNCID_MAX];
char syncidpath[PATH_MAX];
// if we receive syncid, we already marked as successfully done
// only sending confirmation has failed last time
snprintf(lastsyncidpath, PATH_MAX, "%s/%s.syncid.last", config.logdir,
config.resource);
if (fileExists(lastsyncidpath) &&
(readSyncId(lastsyncid, lastsyncidpath, SYNCID_MAX) == 0)) {
if (lastsyncid == syncinit->sync_id) {
// send the confirmation, don't sync
response.continue_ = 0;
response.has_already_synced = 1;
response.already_synced = 1;
sendMessage(cfd, SyncInitResponseType, &response);
return 0; // no files to be synchronized
}
}
int errflag = 0;
// if we can read syncid file, last sync did not finish properly
// revert snapshot
snprintf(syncidpath, PATH_MAX, "%s/%s.syncid", config.logdir,
config.resource);
if (fileExists(syncidpath) &&
(readSyncId(syncid, syncidpath, SYNCID_MAX) == 0)) {
if (syncid == syncinit->sync_id) {
// TODO: here we should support resume
}
// revert last snapshot, check for its existence is necessary, but
// is done nevertheless
if (fileExists(config.snapshot) == 1) {
// do as one block, this should not fail, if yes, we are in trouble
errMsg(LOG_INFO, "Reverting snapshot.");
int ret = 0;
ret = deleteSnapshot(config.rootdir);
ret |= createSnapshot(config.snapshot, config.rootdir, 0);
ret |= deleteSnapshot(config.snapshot);
if (ret != 0) {
errflag = 1;
snprintf(errmsg, ERRMSG_MAX, "Reverting to last snapshot"
"has failed.");
}
}
}
// create snapshot
// snapshot might exists (if last time program crash before sync-id was
// written or before it was deleted), but in this case we don't need to
// revert it
if (!errflag && fileExists(config.snapshot)) {
errMsg(LOG_INFO, "Snapshot %s unexpectedly exists, deleting.",
config.snapshot);
if (deleteSnapshot(config.snapshot) == -1) {
errMsg(LOG_ERR, "Could not delete snapshot %s", config.snapshot);
errflag = 1;
}
}
if (!errflag &&
(createSnapshot(config.rootdir, config.snapshot, 1) != 0)) {
errMsg(LOG_ERR, "Could not create snapshot %s", config.snapshot);
errflag = 1;
}
// write syncid
if (!errflag && (writeSyncId(syncinit->sync_id, syncidpath) != 0)) {
errMsg(LOG_ERR, "Could not write sync-id. Stopping.");
errflag = 1;
}
// send response
int ret;
if (errflag) {
response.continue_ = 0;
snprintf(errmsg, ERRMSG_MAX, "Error in snapshot operation.");
response.error_message = errmsg;
ret = -1;
} else {
response.continue_ = 1;
ret = syncinit->number_files;
}
sync_init__free_unpacked(syncinit, NULL);
if (sendMessage(cfd, SyncInitResponseType, &response) == 0)
return ret;
else
return -1;
}
TEST_F(SnapshotManagerTests, BasicFunctionality) {
if (!snapshotManager)
return; // This test is only for engines that DO support SnapshotMangers.
// Snapshot variables are named according to the size of the RecordStore at the time of the
// snapshot.
auto snap0 = prepareAndCreateSnapshot();
insertRecordAndCommit();
auto snap1 = prepareAndCreateSnapshot();
insertRecordAndCommit();
prepareSnapshot();
insertRecordAndCommit();
auto snap2 = createSnapshot();
{
auto op = makeOperation();
WriteUnitOfWork wuow(op);
insertRecord(op);
prepareSnapshot(); // insert should still be invisible.
ASSERT_EQ(itCountOn(snapshotOperation), 3);
wuow.commit();
}
auto snap3 = createSnapshot();
{
auto op = makeOperation();
WriteUnitOfWork wuow(op);
insertRecord(op);
// rolling back wuow
}
auto snap4 = prepareAndCreateSnapshot();
// If these fail, everything is busted.
snapshotManager->setCommittedSnapshot(snap0);
ASSERT_EQ(itCountCommitted(), 0);
snapshotManager->setCommittedSnapshot(snap1);
ASSERT_EQ(itCountCommitted(), 1);
// If this fails, the snapshot is from the 'create' time rather than the 'prepare' time.
snapshotManager->setCommittedSnapshot(snap2);
ASSERT_EQ(itCountCommitted(), 2);
// If this fails, the snapshot contains writes that weren't yet committed.
snapshotManager->setCommittedSnapshot(snap3);
ASSERT_EQ(itCountCommitted(), 3);
// This op should keep its original snapshot until abandoned.
auto longOp = makeOperation();
ASSERT_OK(longOp->recoveryUnit()->setReadFromMajorityCommittedSnapshot());
ASSERT_EQ(itCountOn(longOp), 3);
// If this fails, the snapshot contains writes that were rolled back.
snapshotManager->setCommittedSnapshot(snap4);
ASSERT_EQ(itCountCommitted(), 4);
// If this fails, longOp changed snapshots at an illegal time.
ASSERT_EQ(itCountOn(longOp), 3);
// If this fails, snapshots aren't preserved while in use.
snapshotManager->cleanupUnneededSnapshots();
ASSERT_EQ(itCountOn(longOp), 3);
// If this fails, longOp didn't get a new snapshot when it should have.
longOp->recoveryUnit()->abandonSnapshot();
ASSERT_EQ(itCountOn(longOp), 4);
}
int synchronize(void) {
int pidfd;
char pidpath[PATH_MAX];
int logfd;
char logpath[PATH_MAX];
int newsync = 0;
// make sure, that there isn't another client process for this resource
// already running
snprintf(pidpath, PATH_MAX, "/var/run/syncedfs/client/%s.pid",
config.resource);
pidfd = createPidFile(config.ident, pidpath, 0);
if (pidfd == -1) {
errMsg(LOG_ERR, "Could not create pid file %s, Exiting sync.", pidpath);
return -1;
}
// if sync log does not exist, switch log
snprintf(logpath, PATH_MAX, "%s/%s.sync", config.logdir, config.resource);
errMsg(LOG_INFO, "logpath: %s", logpath);
logfd = open(logpath, O_RDONLY);
if (logfd == -1) {
if (switchLog() != 0) {
errMsg(LOG_ERR, "Could not switch log file. Stopping.");
return -1;
}
logfd = open(logpath, O_RDONLY);
if (logfd == -1) {
errnoMsg(LOG_ERR, "Could not open log file %s", logpath);
return -1;
}
newsync = 1;
}
// sync-id
char id[SYNCID_MAX];
char idpath[PATH_MAX];
snprintf(idpath, PATH_MAX, "%s/%s.id", config.logdir, config.resource);
// second part of the condition covers weird states after crash etc.
if (newsync == 1 || readSyncId(id, idpath, SYNCID_MAX) != 0) {
if (generateSyncId(id, SYNCID_MAX) != 0) {
errMsg(LOG_ERR, "Could not get sync-id. Stopping.");
return -1;
}
if (writeSyncId(id, idpath) != 0) {
errMsg(LOG_ERR, "Could not write sync-id. Stopping.");
return -1;
}
}
// create snapshot
if (newsync || !fileExists(config.snapshot)) {
if (createSnapshot(config.rootdir, config.snapshot, 1) == -1) {
errMsg(LOG_ERR, "Could not create snapshot of %s to %s Stopping.",
config.rootdir, config.snapshot);
return -1;
}
}
// load log
if (loadLog(logfd) != 0) {
errMsg(LOG_ERR, "Could not load log %s", logpath);
return -1;
}
// transfer changes
if (transfer(config.host, config.port) == -1) {
errMsg(LOG_ERR, "Error in transfer. Exiting sync.");
// in case of failure only delete pid file
if (deletePidFile(pidfd, pidpath) == -1)
errExit(LOG_ERR, "Deleting PID file '%s'", pidpath);
return -1;
}
// delete snapshot
if (deleteSnapshot(config.snapshot) == -1)
errMsg(LOG_ERR, "Could not delete snapshot %s", config.snapshot);
// delete syncid
if (unlink(idpath) == -1)
errExit(LOG_ERR, "Deleting sync-id file '%s'", idpath);
// delete sync log
close(logfd);
if (unlink(logpath) == -1)
errExit(LOG_ERR, "Deleting log file '%s'", logpath);
// delete pid file
if (deletePidFile(pidfd, pidpath) == -1)
errExit(LOG_ERR, "Deleting PID file '%s'", pidpath);
return 0;
}
