wlan: Dampen scan periodicity if no roamable candidates found.
This fix limts the iterations of background scans to find potential roam
candidates in scenarios where there are none (home environment or
enterprise network with coverage holes).
When no roamable candidates are found, we register with a new lookup
threshold and continue to scan if the RSSI of the current AP falls below
the new threshold. However, if we are in an area where the current AP is
the only available candidate and RSSI is below the threshold, we would
endlessly continue to scan. In the interest of
power consumption, we would like to dampen the scans every time there
are no roamable candidates found.
For every scan that results in no candidates, double the scan
periodicity (initialized to 1s) until we hit a max (defined as 60s).
Subsequently, scan every 60s if we continue to not find any candidates.
Once a candidate is found, the periodicity is reset back to 1s.
Change-Id: I8049aab5a8d25f51f6633d2249971678c5a6c2a7
CR-Fixed: 407719
diff --git a/CORE/SME/src/csr/csrNeighborRoam.c b/CORE/SME/src/csr/csrNeighborRoam.c
index 630b8df..0828835 100644
--- a/CORE/SME/src/csr/csrNeighborRoam.c
+++ b/CORE/SME/src/csr/csrNeighborRoam.c
@@ -368,6 +368,9 @@
/* Stop neighbor scan timer */
palTimerStop(pMac->hHdd, pNeighborRoamInfo->neighborScanTimer);
+ /* Stop neighbor scan results refresh timer */
+ palTimerStop(pMac->hHdd, pNeighborRoamInfo->neighborResultsRefreshTimer);
+
/* Abort any ongoing scan */
if (eANI_BOOLEAN_TRUE == pNeighborRoamInfo->scanRspPending)
{
@@ -464,9 +467,10 @@
}
/* Reset thresholds only after deregistering DOWN event from TL */
- pNeighborRoamInfo->currentLookupIncrementMultiplier = 0;
pNeighborRoamInfo->currentNeighborLookupThreshold =
pNeighborRoamInfo->cfgParams.neighborLookupThreshold;
+ pNeighborRoamInfo->currentScanResultsRefreshPeriod =
+ NEIGHBOR_SCAN_RESULTS_REFRESH_PERIOD_MIN;
}
/* ---------------------------------------------------------------------------
@@ -1027,13 +1031,15 @@
while (NULL != (pScanResult = csrScanResultGetNext(pMac, *pScanResultList)))
{
- NEIGHBOR_ROAM_DEBUG(pMac, LOGE, FL("Scan result: BSSID : %02x:%02x:%02x:%02x:%02x:%02x"),
- pScanResult->BssDescriptor.bssId[0],
- pScanResult->BssDescriptor.bssId[1],
- pScanResult->BssDescriptor.bssId[2],
- pScanResult->BssDescriptor.bssId[3],
- pScanResult->BssDescriptor.bssId[4],
- pScanResult->BssDescriptor.bssId[5]);
+ NEIGHBOR_ROAM_DEBUG(pMac, LOGE,
+ FL("Scan result: BSSID %02x:%02x:%02x:%02x:%02x:%02x (Rssi %d)"),
+ pScanResult->BssDescriptor.bssId[0],
+ pScanResult->BssDescriptor.bssId[1],
+ pScanResult->BssDescriptor.bssId[2],
+ pScanResult->BssDescriptor.bssId[3],
+ pScanResult->BssDescriptor.bssId[4],
+ pScanResult->BssDescriptor.bssId[5],
+ abs(pScanResult->BssDescriptor.rssi));
if (VOS_TRUE == vos_mem_compare(pScanResult->BssDescriptor.bssId,
pNeighborRoamInfo->currAPbssid, sizeof(tSirMacAddr)))
@@ -1190,10 +1196,10 @@
there are no valid APs in the scan result for roaming. This means
out AP is the best and no other AP is around. No point in scanning
again and again. Performing the following here.
- 1. Deregister the pre-auth callback from TL
- 2. Stop the neighbor scan timer
- 3. Re-register the neighbor lookup callback with increased pre-auth threshold
- 4. Transition the state to CONNECTED state
+ 1. Remain in eCSR_NEIGHBOR_ROAM_STATE_CFG_CHAN_LIST_SCAN.
+ 2. Stop the neighbor scan timer.
+ 3. Start neighbor scan results refresh timer.
+ 4. Update currentScanResultsRefreshPeriod for next iteration.
\param pMac - The handle returned by macOpen.
@@ -1202,49 +1208,47 @@
---------------------------------------------------------------------------*/
static VOS_STATUS csrNeighborRoamHandleEmptyScanResult(tpAniSirGlobal pMac)
{
- VOS_STATUS vosStatus = VOS_STATUS_SUCCESS;
tpCsrNeighborRoamControlInfo pNeighborRoamInfo = &pMac->roam.neighborRoamInfo;
eHalStatus status = eHAL_STATUS_SUCCESS;
- /* Stop the neighbor scan timer now */
+ /* Stop neighbor scan timer */
status = palTimerStop(pMac->hHdd, pNeighborRoamInfo->neighborScanTimer);
- if (eHAL_STATUS_SUCCESS != status)
+ if (eHAL_STATUS_SUCCESS != status)
{
smsLog(pMac, LOGW, FL(" palTimerStop failed with status %d\n"), status);
}
- /* Increase the neighbor lookup threshold by a constant factor or 1 */
- if ((pNeighborRoamInfo->currentNeighborLookupThreshold+3) < pNeighborRoamInfo->cfgParams.neighborReassocThreshold)
- {
- pNeighborRoamInfo->currentNeighborLookupThreshold += 3;
- }
-
-
#ifdef WLAN_FEATURE_VOWIFI_11R
/* Clear off the old neighbor report details */
vos_mem_zero(&pNeighborRoamInfo->FTRoamInfo.neighboReportBssInfo, sizeof(tCsrNeighborReportBssInfo) * MAX_BSS_IN_NEIGHBOR_RPT);
#endif
- /* Transition to CONNECTED state */
- CSR_NEIGHBOR_ROAM_STATE_TRANSITION(eCSR_NEIGHBOR_ROAM_STATE_CONNECTED)
-
- /* Reset all the necessary variables before transitioning to the CONNECTED state */
- csrNeighborRoamResetConnectedStateControlInfo(pMac);
-
-
- /* Re-register Neighbor Lookup threshold callback with TL */
- NEIGHBOR_ROAM_DEBUG(pMac, LOG2, FL("Registering DOWN event neighbor lookup callback with TL for RSSI = %d"), pNeighborRoamInfo->currentNeighborLookupThreshold * (-1));
- vosStatus = WLANTL_RegRSSIIndicationCB(pMac->roam.gVosContext, (v_S7_t)pNeighborRoamInfo->currentNeighborLookupThreshold * (-1),
- WLANTL_HO_THRESHOLD_DOWN,
- csrNeighborRoamNeighborLookupDOWNCallback,
- VOS_MODULE_ID_SME, pMac);
-
- if(!VOS_IS_STATUS_SUCCESS(vosStatus))
+ /* Start neighbor scan results refresh timer */
+ if (eHAL_STATUS_SUCCESS !=
+ palTimerStart(pMac->hHdd, pNeighborRoamInfo->neighborResultsRefreshTimer,
+ pNeighborRoamInfo->currentScanResultsRefreshPeriod * PAL_TIMER_TO_MS_UNIT,
+ eANI_BOOLEAN_FALSE))
{
- //err msg
- smsLog(pMac, LOGW, FL(" Couldn't re-register csrNeighborRoamNeighborLookupDOWNCallback with TL: Status = %d\n"), status);
+ smsLog(pMac, LOGE, FL("Neighbor results refresh timer failed to start (%d)"), status);
+ vos_mem_free(pNeighborRoamInfo->roamChannelInfo.currentChannelListInfo.ChannelList);
+ pNeighborRoamInfo->roamChannelInfo.currentChannelListInfo.ChannelList = NULL;
+ return VOS_STATUS_E_FAILURE;
}
- return vosStatus;
+ smsLog(pMac, LOG1, FL("Neighbor results refresh timer started (%ld ms)"),
+ (pNeighborRoamInfo->currentScanResultsRefreshPeriod * PAL_TIMER_TO_MS_UNIT));
+
+ /* Update currentScanResultsRefreshPeriod to be used for next iteration */
+ if ( (2*pNeighborRoamInfo->currentScanResultsRefreshPeriod) >
+ NEIGHBOR_SCAN_RESULTS_REFRESH_PERIOD_MAX )
+ {
+ pNeighborRoamInfo->currentScanResultsRefreshPeriod =
+ NEIGHBOR_SCAN_RESULTS_REFRESH_PERIOD_MAX;
+ } else {
+ /* Double the refresh period every time we fail to find candidates */
+ pNeighborRoamInfo->currentScanResultsRefreshPeriod *= 2;
+ }
+
+ return VOS_STATUS_SUCCESS;
}
/* ---------------------------------------------------------------------------
@@ -1344,6 +1348,13 @@
case eCSR_NEIGHBOR_ROAM_STATE_CFG_CHAN_LIST_SCAN:
if (tempVal)
{
+ /*
+ * Since there are non-zero candidates found
+ * after the scan, reset the refresh period
+ * to minimum.
+ */
+ pNeighborRoamInfo->currentScanResultsRefreshPeriod =
+ NEIGHBOR_SCAN_RESULTS_REFRESH_PERIOD_MIN;
#ifdef WLAN_FEATURE_VOWIFI_11R
/* If this is a non-11r association, then we can register the reassoc callback here as we have some
APs in the roamable AP list */
@@ -2863,7 +2874,8 @@
vos_mem_set(pNeighborRoamInfo->currAPbssid, sizeof(tCsrBssid), 0);
pNeighborRoamInfo->currentNeighborLookupThreshold = pMac->roam.neighborRoamInfo.cfgParams.neighborLookupThreshold;
- pNeighborRoamInfo->currentLookupIncrementMultiplier = 0;
+ pNeighborRoamInfo->currentScanResultsRefreshPeriod =
+ NEIGHBOR_SCAN_RESULTS_REFRESH_PERIOD_MIN;
pNeighborRoamInfo->scanRspPending = eANI_BOOLEAN_FALSE;
pNeighborRoamInfo->neighborScanTimerInfo.pMac = pMac;