int
check(account_t *a1, int thread_id)
{
int amount=0;
//lock ordering
int n1=a1->number;
//local_lock_read(&gl);
if (use_locks != 0)
{
acquire_read(&local_th_data[thread_id][n1],&the_locks[n1]);
}
amount = a1->balance;
if (use_locks != 0)
{
MEM_BARRIER;
release_read(cluster_id, &local_th_data[thread_id][n1],&the_locks[n1]);
}
//local_unlock_read(&gl);
return amount;
}
rc_t
log_core::fetch(lsn_t& ll, void* buf, lsn_t* nxt, const bool forward)
{
INC_TSTAT(log_fetches);
lintel::atomic_thread_fence(lintel::memory_order_acquire);
if (ll < _fetch_buf_end && ll >= _fetch_buf_begin)
{
// log record can be found in fetch buffer -- no I/O
size_t i = ll.hi() - _fetch_buf_first;
if (_fetch_buffers[i]) {
logrec_t* rp = (logrec_t*) (_fetch_buffers[i] + ll.lo());
w_assert1(rp->valid_header(ll));
if (rp->type() == logrec_t::t_skip)
{
if (forward) {
ll = lsn_t(ll.hi() + 1, 0);
return fetch(ll, buf, nxt, forward);
}
else { // backward scan
ll = *((lsn_t*) (_fetch_buffers[i] + ll.lo() - sizeof(lsn_t)));
}
rp = (logrec_t*) (_fetch_buffers[i] + ll.lo());
w_assert1(rp->valid_header(ll));
}
if (nxt) {
if (!forward && ll.lo() == 0) {
auto p = _storage->get_partition(ll.hi() - 1);
*nxt = p ? lsn_t(p->num(), p->get_size()) : lsn_t::null;
}
else {
if (forward) {
*nxt = ll;
nxt->advance(rp->length());
}
else {
memcpy(nxt, (char*) rp - sizeof(lsn_t), sizeof(lsn_t));
}
}
}
memcpy(buf, rp, rp->length());
INC_TSTAT(log_buffer_hit);
return RCOK;
}
}
if (forward && ll >= durable_lsn()) {
w_assert1(ll == durable_lsn());
// reading the durable_lsn during recovery yields a skip log record,
return RC(eEOF);
}
if (!forward && ll == lsn_t::null) {
// for a backward scan, nxt pointer is set to null
// when the first log record in the first partition is set
return RC(eEOF);
}
auto p = _storage->get_partition(ll.hi());
if(!p) { return RC(eEOF); }
W_DO(p->open_for_read());
logrec_t* rp;
lsn_t prev_lsn = lsn_t::null;
DBGOUT3(<< "fetch @ lsn: " << ll);
W_COERCE(p->read(rp, ll, forward ? nullptr : &prev_lsn));
w_assert1(rp->valid_header(ll));
// handle skip log record
if (rp->type() == logrec_t::t_skip)
{
p->release_read();
if (forward) {
DBGTHRD(<<"seeked to skip" << ll );
DBGTHRD(<<"getting next partition.");
ll = lsn_t(ll.hi() + 1, 0);
p = _storage->get_partition(ll.hi());
if(!p) { return RC(eEOF); }
// re-read
DBGOUT3(<< "fetch @ lsn: " << ll);
W_DO(p->open_for_read());
W_COERCE(p->read(rp, ll));
w_assert1(rp->valid_header(ll));
}
else { // backward scan
