//! Sum inData[0:count-1] over all processors into outData.
void
globalVectorSum (const Datum inData[],
Datum outData[],
const int count)
{
safeCopy (inData, outData, count);
}
/// \brief Exchange data between processors.
///
/// Exchange sencRecvCount elements of sendData with processor
/// destProc, receiving the result into recvData. Assume that
/// sendData and recvData do not alias one another.
///
/// \param sendData [in] Array of value-type elements to send
/// \param recvData [out] Array of value-type elements to
/// receive. Caller is responsible for making sure that
/// recvData does not alias sendData.
/// \param sendRecvCount [in] Number of elements to send and
/// receive in the array
/// \param destProc [in] The "other" process' rank (to which
/// this process is sending data, and from which this process is
/// receiving data)
/// \param tag [in] MPI tag (ignored)
void
swapData (const Datum sendData[],
Datum recvData[],
const int sendRecvCount,
const int destProc,
const int tag)
{
if (destProc != rank())
{
std::ostringstream os;
os << "Destination rank " << destProc << " is invalid. The only "
<< "valid rank for TSQR::TrivialMessenger is 0 (zero).";
throw std::invalid_argument (os.str());
}
else if (sendRecvCount < 0)
{
std::ostringstream os;
os << "sendRecvCount = " << sendRecvCount << " is invalid: "
<< "only nonnegative values are allowed.";
throw std::invalid_argument (os.str());
}
else if (sendRecvCount == 0)
return; // No data to exchange
else
safeCopy (sendData, recvData, sendRecvCount);
}
int Scheduler::futexWakeOp(uint32_t pid, uint32_t tid, FutexInfo fi) {
DEBUG_FUTEX("Scheduler: FUTEX WAKE OP called with pid %u tid %u", pid, tid);
int *oldVal = 0; // int oldval = *(int *) uaddr2;
if(!safeCopy(fi.uaddr2, oldVal)) {
panic("Futex Wake Op wasn't able to copy the data.");
}
// |op |cmp| oparg | cmparg |
// 4 4 12 12 <== # of bits
int op = (fi.val3 & 0xf) >> 28; // (((op & 0xf) << 28) |
int cmp = (fi.val3 & 0xf) >> 24; // ((cmp & 0xf) << 24) |
int oparg = (fi.val3 & 0xfff) >> 12; // ((oparg & 0xfff) << 12) |
int cmparg = (fi.val3 & 0xfff); // (cmparg & 0xfff))
// Bit-wise ORing the following value into op causes
// (1 << oparg) to be used as the operand: FUTEX_OP_ARG_SHIFT 8
if(op & 8) { oparg = 1 << oparg; }
int *newVal; *newVal = 0; // *(int *) uaddr2 = oldval op oparg;
switch (op) { //Op is defined as:
case 0: // FUTEX_OP_SET 0 /* uaddr2 = oparg; */
*newVal = oparg;
case 1: // FUTEX_OP_ADD 1 /* uaddr2 += oparg; */
*newVal = *(fi.uaddr2) + oparg;
case 2: // FUTEX_OP_OR 2 /* uaddr2 |= oparg; */
*newVal = *(fi.uaddr2) | oparg;
case 3: // FUTEX_OP_ANDN 3 /* uaddr2 &= ~oparg; */
*newVal = *(fi.uaddr2) & ~oparg;
case 4: // FUTEX_OP_XOR 4 /* uaddr2 ^= oparg; */
*newVal = *(fi.uaddr2) ^ oparg;
default:
panic("We are missing an op type in sched wake op");
}
int waitersToWake = futexWakeNWaiters(false, 0xffffffff, fi.uaddr, fi.val);
bool cmpResult = false;
switch (cmp) { // The cmp field is one of the following:
case 0: // FUTEX_OP_CMP_EQ 0 /* if (oldval == cmparg) wake */
cmpResult = (*oldVal == cmparg);
case 1: // FUTEX_OP_CMP_NE 1 /* if (oldval != cmparg) wake */
cmpResult = (*oldVal != cmparg);
case 2: // FUTEX_OP_CMP_LT 2 /* if (oldval < cmparg) wake */
cmpResult = (*oldVal < cmparg);
case 3: // FUTEX_OP_CMP_LE 3 /* if (oldval <= cmparg) wake */
cmpResult = (*oldVal <= cmparg);
case 4: // FUTEX_OP_CMP_GT 4 /* if (oldval > cmparg) wake */
cmpResult = (*oldVal > cmparg);
case 5: // FUTEX_OP_CMP_GE 5 /* if (oldval >= cmparg) wake */
cmpResult = (*oldVal >= cmparg);
default:
panic("We are missing a case for cmp");
}
int extraWaitersToWake = 0;
if(cmpResult) { // if (oldval cmp cmparg)
// futex(uaddr2, FUTEX_WAKE, val2, 0, 0, 0);
extraWaitersToWake = futexWakeNWaiters(false, 0xffffffff, newVal, fi.val2);
}
return waitersToWake + extraWaitersToWake;
}
int Scheduler::futexCmpReque(bool pi_wake, uint32_t pid, uint32_t tid, FutexInfo fi) {
DEBUG_FUTEX("Scheduler: FUTEX CMP REQUE called with pi %d pid %u tid %u", pi_wake, pid, tid);
int *curVal = 0;
if(!safeCopy(fi.uaddr, curVal)) {
panic("Futex Wait wasn't able to copy the data.");
}
if(fi.val3 != *curVal) {
DEBUG_FUTEX("Cur val didn't match val in futex wait");
return 0;
}
bool extraWaiters = futexTable[fi.uaddr].size() > (uint32_t)fi.val;
int waitersToWake = 0;
if(!pi_wake) {
futexWakeNWaiters(pi_wake, 0xffffffff, fi.uaddr, fi.val);
}
int extraWaitersToWake = 0;
if(extraWaiters) {
extraWaitersToWake = futexMoveNWaiters(pi_wake, fi.uaddr, fi.uaddr2, fi.val2);
}
return waitersToWake + extraWaitersToWake;
}