radioInterface: Atomically fetch and change underrun variable
Otherwise, it could happen that underrun events are lost:
TxLower (isUnderrun): RxLower (pullBuffer):
read(underrun)
read(underrun)
write(underrun, |val) [maybe underrun becomes TRUE]
write(underrun, false)
Similary, it could happen the other direction if atomic was only applied
to isUnderrun:
TxLower (isUnderrun): RxLower (pullBuffer):
read(underrun) -> true
read(underrun)-> true
write(underrun, false)
write(underrun, true|val) where val=false
So in here isUnderrun would return true twice while it should only
return one.
Change-Id: I684e0a5d2a9583a161d5a6593559b3a9e7cd57e3
diff --git a/Transceiver52M/osmo-trx.cpp b/Transceiver52M/osmo-trx.cpp
index ab0b631..9fe6585 100644
--- a/Transceiver52M/osmo-trx.cpp
+++ b/Transceiver52M/osmo-trx.cpp
@@ -571,6 +571,11 @@
#endif
#endif
+#ifndef HAVE_ATOMIC_OPS
+#pragma message ("Built without atomic operation support. Using Mutex, it may affect performance!")
+ printf("Built without atomic operation support. Using Mutex, it may affect performance!\n");
+#endif
+
if (!log_mutex_init()) {
fprintf(stderr, "Failed to initialize log mutex!\n");
exit(2);
diff --git a/Transceiver52M/radioInterface.cpp b/Transceiver52M/radioInterface.cpp
index 6e49a75..fbcacf1 100644
--- a/Transceiver52M/radioInterface.cpp
+++ b/Transceiver52M/radioInterface.cpp
@@ -24,6 +24,7 @@
#include "radioInterface.h"
#include "Resampler.h"
#include <Logger.h>
+#include <Threads.h>
extern "C" {
#include "convert.h"
@@ -288,9 +289,9 @@
bool RadioInterface::isUnderrun()
{
- bool retVal = underrun;
- underrun = false;
-
+ bool retVal;
+ /* atomically get previous value of "underrun" and set the var to false */
+ retVal = osmo_trx_sync_fetch_and_and(&underrun, false);
return retVal;
}
@@ -340,7 +341,7 @@
segmentLen * 2);
}
- underrun |= local_underrun;
+ osmo_trx_sync_or_and_fetch(&underrun, local_underrun);
readTimestamp += numRecv;
return 0;
}
@@ -366,7 +367,7 @@
segmentLen,
&local_underrun,
writeTimestamp);
- underrun |= local_underrun;
+ osmo_trx_sync_or_and_fetch(&underrun, local_underrun);
writeTimestamp += numSent;
return true;
diff --git a/Transceiver52M/radioInterface.h b/Transceiver52M/radioInterface.h
index b12c187..d72fb69 100644
--- a/Transceiver52M/radioInterface.h
+++ b/Transceiver52M/radioInterface.h
@@ -48,7 +48,7 @@
std::vector<short *> convertRecvBuffer;
std::vector<short *> convertSendBuffer;
std::vector<float> powerScaling;
- bool underrun; ///< indicates writes to USRP are too slow
+ int underrun; ///< indicates writes to USRP are too slow
bool overrun; ///< indicates reads from USRP are too slow
TIMESTAMP writeTimestamp; ///< sample timestamp of next packet written to USRP
TIMESTAMP readTimestamp; ///< sample timestamp of next packet read from USRP
diff --git a/Transceiver52M/radioInterfaceMulti.cpp b/Transceiver52M/radioInterfaceMulti.cpp
index eec426e..92e31e1 100644
--- a/Transceiver52M/radioInterfaceMulti.cpp
+++ b/Transceiver52M/radioInterfaceMulti.cpp
@@ -251,7 +251,7 @@
convert_short_float((float *) outerRecvBuffer->begin(),
convertRecvBuffer[0], 2 * outerRecvBuffer->size());
- underrun |= local_underrun;
+ osmo_trx_sync_or_and_fetch(&underrun, local_underrun);
readTimestamp += num;
channelizer->rotate((float *) outerRecvBuffer->begin(),
@@ -348,7 +348,7 @@
LOG(ALERT) << "Transmit error " << num;
}
- underrun |= local_underrun;
+ osmo_trx_sync_or_and_fetch(&underrun, local_underrun);
writeTimestamp += num;
return true;
diff --git a/Transceiver52M/radioInterfaceResamp.cpp b/Transceiver52M/radioInterfaceResamp.cpp
index 864cdee..b92432f 100644
--- a/Transceiver52M/radioInterfaceResamp.cpp
+++ b/Transceiver52M/radioInterfaceResamp.cpp
@@ -184,7 +184,7 @@
convert_short_float((float *) outerRecvBuffer->begin(),
convertRecvBuffer[0], 2 * resamp_outchunk);
- underrun |= local_underrun;
+ osmo_trx_sync_or_and_fetch(&underrun, local_underrun);
readTimestamp += (TIMESTAMP) resamp_outchunk;
/* Write to the end of the inner receive buffer */
@@ -232,7 +232,7 @@
LOG(ALERT) << "Transmit error " << numSent;
}
- underrun |= local_underrun;
+ osmo_trx_sync_or_and_fetch(&underrun, local_underrun);
writeTimestamp += resamp_outchunk;
return true;