NDIS_STATUS
Hvl11RegisterVNic(
_In_ PHVL pHvl,
_In_ PVNIC pVNic
)
{
NDIS_STATUS ndisStatus = NDIS_STATUS_SUCCESS;
PHVL_CONTEXT pCtx = NULL;
do
{
HvlLock(pHvl);
// add it to the HVL's list of VNICs
InsertTailList(&pHvl->VNiclist, &pVNic->VNicLink);
HvlAssignVNicToContext(pHvl, pVNic, &pCtx);
/*
Initially make it part of the inactive context list. It will be picked up whenever we
next context switch to it
*/
InsertTailList(&pHvl->InactiveContextList, &pCtx->Link);
HvlUnlock(pHvl);
// notify it of any existing cached notifications
if (pHvl->CachedChannelNotification.Header.pSourceVNic)
{
VNic11Notify(pVNic, &pHvl->CachedChannelNotification);
}
} while (FALSE);
return ndisStatus;
}
VOID
HvlNotifyAllVNics(
PHVL pHvl,
PVOID pvNotif
)
{
LIST_ENTRY *pEntryVNic = NULL;
PVNIC pVNic = NULL;
PNOTIFICATION_DATA_HEADER pHdr = NULL;
ASSERT(HvlIsLocked(pHvl));
pHdr = (PNOTIFICATION_DATA_HEADER)pvNotif;
pEntryVNic = pHvl->VNiclist.Flink;
while (pEntryVNic != &pHvl->VNiclist)
{
pVNic = CONTAINING_RECORD(pEntryVNic, VNIC, VNicLink);
// do not notify if this VNIC is the source of the notification
if (pVNic != pHdr->pSourceVNic)
{
_Analysis_assume_lock_held_(pHvl->Lock.SpinLock);
HvlUnlock(pHvl);
VNic11Notify(pVNic, pvNotif);
HvlLock(pHvl);
}
pEntryVNic = pEntryVNic->Flink;
}
// Also send the notification to the helper port
pEntryVNic = pHvl->pHelperPortCtx->VNicList.Flink;
pVNic = CONTAINING_RECORD(pEntryVNic, VNIC, CtxLink);
_Analysis_assume_lock_held_(pHvl->Lock.SpinLock);
HvlUnlock(pHvl);
VNic11Notify(pVNic, pvNotif);
HvlLock(pHvl);
}
USHORT
HwSelectTXDataRate(
__in PHW_MAC_CONTEXT HwMac,
__in PDOT11_RATE_SET RemoteRateSet,
__in ULONG LinkQuality
)
{
PDOT11_RATE_SET operationalRateSet;
PDOT11_RATE_SET activeRateSet;
ULONG indexLocalRates;
ULONG indexRemoteRates;
USHORT maximumRate;
OP_RATE_CHANGE_NOTIFICATION rateNotification;
// The active rate set structure needs to be protected
HW_ACQUIRE_HARDWARE_LOCK(HwMac->Hw, FALSE);
//
// Select the best rate supported by both AP and us.
//
operationalRateSet = &(HwMac->PhyContext[HwMac->OperatingPhyId].OperationalRateSet);
activeRateSet = &(HwMac->PhyContext[HwMac->OperatingPhyId].ActiveRateSet);
activeRateSet->uRateSetLength = 0;
//
// We merge the rates from the AP and the client to create the
// currently active data rates table
//
for (indexLocalRates = 0; indexLocalRates < operationalRateSet->uRateSetLength; indexLocalRates++)
{
for (indexRemoteRates = 0; indexRemoteRates < RemoteRateSet->uRateSetLength; indexRemoteRates++)
{
if (operationalRateSet->ucRateSet[indexLocalRates] == (RemoteRateSet->ucRateSet[indexRemoteRates] & 0x7f))
{
activeRateSet->ucRateSet[activeRateSet->uRateSetLength] =
operationalRateSet->ucRateSet[indexLocalRates];
activeRateSet->uRateSetLength++;
break;
}
}
}
//
// If we dont find any rates, we will stick with our management packet rate
//
if (activeRateSet->uRateSetLength == 0)
{
activeRateSet->ucRateSet[0] = (UCHAR)HalGetBeaconRate(HwMac->Hw->Hal, HwMac->OperatingPhyId);
activeRateSet->uRateSetLength = 1;
}
else if (activeRateSet->uRateSetLength > 1)
{
// bubble sort data rates in ascending order
INT i, j;
UCHAR temp;
for (i = activeRateSet->uRateSetLength - 1; i >= 0; i--)
{
for (j = 1; j <= i; j++)
{
if (activeRateSet->ucRateSet[j - 1] >
activeRateSet->ucRateSet[j])
{
temp = activeRateSet->ucRateSet[j - 1];
activeRateSet->ucRateSet[j - 1] =
activeRateSet->ucRateSet[j];
activeRateSet->ucRateSet[j] = temp;
}
}
}
}
//
// Now that the active rate set is populated and updated, select
// the best rate
//
//
// Determine what the maximum TX rate should be
//
maximumRate = HW11_MAX_DATA_RATE; // Start with max supported by HW
if (LinkQuality < HW_LOW_RATE_LINK_QUALITY_THRESHOLD)
{
//
// The link quality is low, we will go for the lower start rate instead of
// the max supported. The hardware does rate fallback, so we pick
// something that would cause the least number of retrys
//
maximumRate = HW_LOW_RATE_MAX_DATA_RATE;
}
//
// Check if this is greater than max permitted value read from the registry
//
if (maximumRate > HwMac->Hw->RegInfo.MaximumTxRate)
{
maximumRate = (USHORT)HwMac->Hw->RegInfo.MaximumTxRate;
}
//
// Now find the best matching rate between us and the AP
//
for (indexLocalRates = activeRateSet->uRateSetLength - 1;
indexLocalRates > 0;
indexLocalRates--)
{
//
// Check for a rate supported by both us and the AP that is below the max we prefer to use
//
if (activeRateSet->ucRateSet[indexLocalRates] <= maximumRate)
{
//
// Found the rate we want to use
//
break;
}
}
HwMac->DefaultTXDataRate = activeRateSet->ucRateSet[indexLocalRates];
// Update our rate info table. In our current implementation this is not-per peer
HwMac->RateInfo.CurrentTXDataRate = HwMac->DefaultTXDataRate;
MpTrace(COMP_ASSOC, DBG_LOUD, ("TX Data rate: %d\n", HwMac->DefaultTXDataRate));
HW_RELEASE_HARDWARE_LOCK(HwMac->Hw, FALSE);
//
// Indicate NDIS_STATUS_LINK_STATE to inform the OS about the new
// link speed
//
HwIndicateLinkSpeed(HwMac, HwMac->DefaultTXDataRate);
// Indicate change of link speed to the port so that it
// can take any necessary action
rateNotification.Header.Type = NotificationOpRateChange;
rateNotification.Header.Size = sizeof(OP_RATE_CHANGE_NOTIFICATION);
rateNotification.Header.pSourceVNic = NULL;
rateNotification.NewRate = HwMac->DefaultTXDataRate;
rateNotification.OldRate = 0;
rateNotification.LowestRate = FALSE;
VNic11Notify(HwMac->VNic, &rateNotification);
return (UCHAR)HwMac->DefaultTXDataRate;
}
/*
Tx rate adaptation algorithm:
Preconditions to update tx data rate:
1) device is in connect state;
2)device has sent at least 100 data packets
retransmitPercentage = (toal retry) / (total packets sent)
if retransmit percentage <= threshold for rate increase which default to 35%
if not sending at the highest rate
if previously came down from higher rate and wait count < wait required
increase wait count and exit
else
if not previously came down from higher rate
reset wait required
else leave wait required unchanged
increase current tx rate to next higher rate, reset all other counters and exit
if retransmit percentage >= threshold for roam which default to 350%
if already send at the lowest rate
try to roam to a better AP, reset all counters and exit
else if there are at least fallback skip (which default to 3) lower data rates available
reduce current tx rate to third lower data rate, reset all counters and exit
else if current sending at second lowest rate
set current tx rate to the lowest value, reset all counters and exit
else fall through to following rate fallback handler
if retransmit percentage >= threshold for rate fallback which default to 125%
and not sending at the lowest rate
if previously came up from lower rate
double current wait required
else reset wait required
reduce current tx rate to next lower value, reset all other counters and exit
*/
VOID
HwUpdateTxDataRate(
__in PHW_MAC_CONTEXT MacContext
)
{
PDOT11_RATE_SET activeRateSet;
PHW_RATE_INFO rateInfo = &MacContext->RateInfo; // We are not doing per peer rate adaptation
ULONG rateIndex = 0;
USHORT prevTxRate = 0;
ULONG totalRetry = rateInfo->TotalRetryCount;
ULONG totalSend = rateInfo->PacketsSentForTxRateCheck;
ULONG retransmitPercentage = 0;
OP_RATE_CHANGE_NOTIFICATION rateNotification;
if (HW_TEST_MAC_CONTEXT_STATUS(MacContext, HW_MAC_CONTEXT_CANNOT_SEND_FLAGS) ||
!HW_TEST_MAC_CONTEXT_STATUS(MacContext, HW_MAC_CONTEXT_LINK_UP))
{
// MAC context wont be sending to a peer. There isnt anything for us to do
return;
}
// Check the send threshold
if (totalSend < MacContext->Hw->RegInfo.MinPacketsSentForTxRateUpdate)
{
return;
}
// reset counters
InterlockedExchange(&rateInfo->TotalRetryCount, 0);
InterlockedExchange((LONG*)&rateInfo->PacketsSentForTxRateCheck, 0);
// The active rate set structure needs to be protected
HW_ACQUIRE_HARDWARE_LOCK(MacContext->Hw, FALSE);
do
{
activeRateSet = &(MacContext->PhyContext[MacContext->OperatingPhyId].ActiveRateSet);
for (rateIndex = 0; rateIndex < activeRateSet->uRateSetLength; rateIndex++)
{
if (rateInfo->CurrentTXDataRate == activeRateSet->ucRateSet[rateIndex])
{
prevTxRate = rateInfo->CurrentTXDataRate;
break;
}
}
// prevTxRate equals 0 means rateInfo->CurrentTXDataRate
// is not in activeRateSet->ucRateSet list
if (prevTxRate == 0)
{
MpTrace(COMP_MISC, DBG_LOUD, ("Current TX data rate is not in active rate set\n"));
break;
}
retransmitPercentage = totalRetry * 100 / totalSend;
MpTrace(COMP_TESTING, DBG_TRACE, ("%s: retransmitPercentage=%d(%d/%d), waitCount=%d, "
"waitRequired=%d, prevRate=%d\n",
__FUNCTION__,
retransmitPercentage, totalRetry, totalSend,
rateInfo->TxRateIncreaseWaitCount,
rateInfo->TxRateIncreaseWaitRequired,
rateInfo->PrevTxDataRate));
if (retransmitPercentage <= MacContext->Hw->RegInfo.TxFailureThresholdForRateIncrease)
{
// Consider going up
if (rateIndex < activeRateSet->uRateSetLength - 1)
{
if ((rateInfo->PrevTxDataRate == activeRateSet->ucRateSet[rateIndex + 1]) &&
(rateInfo->TxRateIncreaseWaitCount + 1 < rateInfo->TxRateIncreaseWaitRequired))
{
// I just came down from the rate above me, i dont want to go up yet due to WaitRequired
rateInfo->TxRateIncreaseWaitCount++;
MpTrace(COMP_TESTING, DBG_TRACE, ("%s: WAIT before increasing Tx rate. retransmitPercentage=%d(%d/%d), "
"waitCount=%d, waitRequired=%d, prevRate=%d\n",
__FUNCTION__,
retransmitPercentage, totalRetry, totalSend, rateInfo->TxRateIncreaseWaitCount,
rateInfo->TxRateIncreaseWaitRequired, rateInfo->PrevTxDataRate));
}
else
{
// 1. I came down rate above me and WaitCount >= WaitRequired
// 2. I came up from rate below me, no need to wait for additional time
if (rateInfo->PrevTxDataRate != activeRateSet->ucRateSet[rateIndex + 1])
{
// Case 2 above
rateInfo->TxRateIncreaseWaitRequired = 1;
}
else
{
// Case 1 above
/** don't reset TxRateIncreaseWaitRequired as we need to double */
/** the value if fallback to the current rate again */
}
rateInfo->PrevTxDataRate = rateInfo->CurrentTXDataRate;
rateInfo->TxRateIncreaseWaitCount = 0;
MpTrace(COMP_TESTING, DBG_TRACE, ("%s: increasing Tx data rate from %d to %d. "
"retransmitPercentage = %d(%d/%d), waitCount=%d, waitRequired=%d, prevRate=%d\n",
__FUNCTION__,
rateInfo->CurrentTXDataRate, activeRateSet->ucRateSet[rateIndex + 1],
retransmitPercentage, totalRetry, totalSend,
rateInfo->TxRateIncreaseWaitCount,
rateInfo->TxRateIncreaseWaitRequired,
rateInfo->PrevTxDataRate));
rateInfo->CurrentTXDataRate = activeRateSet->ucRateSet[rateIndex + 1];
}
}
break;
}
if (retransmitPercentage >= MacContext->Hw->RegInfo.TxFailureThresholdForRoam)
{
ULONG rateSkipLevel = MacContext->Hw->RegInfo.TxDataRateFallbackSkipLevel;
// Really large retry count, consider roaming
if (rateIndex == 0)
{
// I am sending at the lowest rate. Either roam or disconnect.
MpTrace(COMP_TESTING, DBG_TRACE, ("%s: too many retransmit happened while "
"transmitting at the lowest data rate. Attempting to roam. "
"retransmitPercentage=%d(%d/%d), waitCount=%d, waitRequired=%d, prevRate=%d",
__FUNCTION__,
retransmitPercentage, totalRetry, totalSend,
rateInfo->TxRateIncreaseWaitCount,
rateInfo->TxRateIncreaseWaitRequired,
rateInfo->PrevTxDataRate));
// Our packets arent going through, jump up to using best data rate &
// hopefully our packets will go through
rateInfo->CurrentTXDataRate = activeRateSet->ucRateSet[activeRateSet->uRateSetLength - 1];
// reset counters
rateInfo->PrevTxDataRate = 0;
rateInfo->TxRateIncreaseWaitRequired = 1;
rateInfo->TxRateIncreaseWaitCount = 0;
break;
}
else if (rateIndex >= rateSkipLevel)
{
// try to go down three rates
MpTrace(COMP_TESTING, DBG_TRACE, ("%s: too many retransmit happened. Reducing Tx rate from %d to %d.\n",
__FUNCTION__,
rateInfo->CurrentTXDataRate,
activeRateSet->ucRateSet[rateIndex - rateSkipLevel]));
rateInfo->CurrentTXDataRate = activeRateSet->ucRateSet[rateIndex - rateSkipLevel];
rateInfo->PrevTxDataRate = 0;
rateInfo->TxRateIncreaseWaitRequired = 1;
rateInfo->TxRateIncreaseWaitCount = 0;
break;
}
else if (rateIndex != 1)
{
// set tx rate to the lowest rate
MpTrace(COMP_TESTING, DBG_TRACE, ("%s: too many retransmit happened. Reducing Tx rate from "
"%d to lowest %d.\n",
__FUNCTION__,
rateInfo->CurrentTXDataRate,
activeRateSet->ucRateSet[0]));
rateInfo->CurrentTXDataRate = activeRateSet->ucRateSet[0];
rateInfo->PrevTxDataRate = 0;
rateInfo->TxRateIncreaseWaitRequired = 1;
rateInfo->TxRateIncreaseWaitCount = 0;
break;
}
else
{
// rateIndex equals to 1. this is the same as lowering tx rate by 1 level
// which is what rate fallback handler does. fall through.
}
}
if ((retransmitPercentage >= MacContext->Hw->RegInfo.TxFailureThresholdForRateFallback) && (rateIndex > 0))
{
// consider going down. no need to wait for additional time
if (rateInfo->PrevTxDataRate == activeRateSet->ucRateSet[rateIndex - 1])
{
rateInfo->TxRateIncreaseWaitRequired *= 2;
}
else
{
rateInfo->TxRateIncreaseWaitRequired = 1;
}
rateInfo->PrevTxDataRate = rateInfo->CurrentTXDataRate;
rateInfo->TxRateIncreaseWaitCount = 0;
MpTrace(COMP_TESTING, DBG_TRACE, ("%s: reducing Tx data rate from %d to %d. "
"retransmitPercentage=%d(%d/%d), waitCount=%d, waitRequired=%d, prevRate=%d\n",
__FUNCTION__,
rateInfo->CurrentTXDataRate,
activeRateSet->ucRateSet[rateIndex - 1],
retransmitPercentage, totalRetry, totalSend,
rateInfo->TxRateIncreaseWaitCount,
rateInfo->TxRateIncreaseWaitRequired,
rateInfo->PrevTxDataRate));
rateInfo->CurrentTXDataRate = activeRateSet->ucRateSet[rateIndex - 1];
break;
}
} while (FALSE);
HW_RELEASE_HARDWARE_LOCK(MacContext->Hw, FALSE);
if (prevTxRate != rateInfo->CurrentTXDataRate)
{
// Indicate new link speed
HwIndicateLinkSpeed(MacContext, rateInfo->CurrentTXDataRate);
// Indicate change of link speed to the port so that it
// can take any necessary action
rateNotification.Header.Type = NotificationOpRateChange;
rateNotification.Header.Size = sizeof(OP_RATE_CHANGE_NOTIFICATION);
rateNotification.Header.pSourceVNic = NULL;
rateNotification.NewRate = rateInfo->CurrentTXDataRate;
rateNotification.OldRate = prevTxRate;
if (rateIndex == 0)
rateNotification.LowestRate = TRUE;
else
rateNotification.LowestRate = FALSE;
VNic11Notify(MacContext->VNic, &rateNotification);
}
}