# include "h/socket.h"
# endif
# include "netinet/in.h"
+# ifdef AFS_SUN58_ENV
+# include "netinet/ip6.h"
+# endif
# ifdef AFS_SUN57_ENV
# include "inet/common.h"
# include "inet/ip.h"
static unsigned int rxi_rpc_process_stat_cnt;
+/*
+ * rxi_busyChannelError is the error to return to the application when a call
+ * channel appears busy (inferred from the receipt of RX_PACKET_TYPE_BUSY
+ * packets on the channel), and there are other call channels in the
+ * connection that are not busy. If 0, we do not return errors upon receiving
+ * busy packets; we just keep trying on the same call channel until we hit a
+ * timeout.
+ */
+static afs_int32 rxi_busyChannelError = 0;
+
rx_atomic_t rx_nWaiting = RX_ATOMIC_INIT(0);
rx_atomic_t rx_nWaited = RX_ATOMIC_INIT(0);
return rx_InitHost(htonl(INADDR_ANY), port);
}
+/**
+ * Sets the error generated when a busy call channel is detected.
+ *
+ * @param[in] error The error to return for a call on a busy channel.
+ *
+ * @pre Neither rx_Init nor rx_InitHost have been called yet
+ */
+void
+rx_SetBusyChannelError(afs_int32 error)
+{
+ osi_Assert(rxinit_status != 0);
+ rxi_busyChannelError = error;
+}
+
/* called with unincremented nRequestsRunning to see if it is OK to start
* a new thread in this service. Could be "no" for two reasons: over the
* max quota, or would prevent others from reaching their min quota.
for (i = 0; i < RX_MAXCALLS; i++) {
conn->twind[i] = rx_initSendWindow;
conn->rwind[i] = rx_initReceiveWindow;
+ conn->lastBusy[i] = 0;
}
RXS_NewConnection(securityObject, conn);
struct rx_call *
rx_NewCall(struct rx_connection *conn)
{
- int i, wait;
+ int i, wait, ignoreBusy = 1;
struct rx_call *call;
struct clock queueTime;
+ afs_uint32 leastBusy = 0;
SPLVAR;
clock_NewTime();
for (i = 0; i < RX_MAXCALLS; i++) {
call = conn->call[i];
if (call) {
+ if (!ignoreBusy && conn->lastBusy[i] != leastBusy) {
+ /* we're not ignoring busy call slots; only look at the
+ * call slot that is the "least" busy */
+ continue;
+ }
+
if (call->state == RX_STATE_DALLY) {
MUTEX_ENTER(&call->lock);
if (call->state == RX_STATE_DALLY) {
+ if (ignoreBusy && conn->lastBusy[i]) {
+ /* if we're ignoring busy call slots, skip any ones that
+ * have lastBusy set */
+ if (leastBusy == 0 || conn->lastBusy[i] < leastBusy) {
+ leastBusy = conn->lastBusy[i];
+ }
+ MUTEX_EXIT(&call->lock);
+ continue;
+ }
+
/*
* We are setting the state to RX_STATE_RESET to
* ensure that no one else will attempt to use this
MUTEX_EXIT(&call->lock);
}
} else {
+ if (ignoreBusy && conn->lastBusy[i]) {
+ /* if we're ignoring busy call slots, skip any ones that
+ * have lastBusy set */
+ if (leastBusy == 0 || conn->lastBusy[i] < leastBusy) {
+ leastBusy = conn->lastBusy[i];
+ }
+ continue;
+ }
+
/* rxi_NewCall returns with mutex locked */
call = rxi_NewCall(conn, i);
MUTEX_ENTER(&rx_refcnt_mutex);
}
}
if (i < RX_MAXCALLS) {
+ conn->lastBusy[i] = 0;
break;
}
if (!wait)
continue;
+ if (leastBusy && ignoreBusy) {
+ /* we didn't find a useable call slot, but we did see at least one
+ * 'busy' slot; look again and only use a slot with the 'least
+ * busy time */
+ ignoreBusy = 0;
+ continue;
+ }
MUTEX_ENTER(&conn->conn_data_lock);
conn->flags |= RX_CONN_MAKECALL_WAITING;
MUTEX_EXIT(&call->lock);
MUTEX_ENTER(&conn->conn_call_lock);
MUTEX_ENTER(&call->lock);
+
+ if (!(call->flags & RX_CALL_PEER_BUSY)) {
+ conn->lastBusy[call->channel] = 0;
+ }
+
MUTEX_ENTER(&conn->conn_data_lock);
conn->flags |= RX_CONN_BUSY;
if (conn->flags & RX_CONN_MAKECALL_WAITING) {
return conn;
}
+/**
+ * Timeout a call on a busy call channel if appropriate.
+ *
+ * @param[in] call The busy call.
+ *
+ * @pre 'call' is marked as busy (namely,
+ * call->conn->lastBusy[call->channel] != 0)
+ *
+ * @pre call->lock is held
+ * @pre rxi_busyChannelError is nonzero
+ *
+ * @note call->lock is dropped and reacquired
+ */
+static void
+rxi_CheckBusy(struct rx_call *call)
+{
+ struct rx_connection *conn = call->conn;
+ int channel = call->channel;
+ int freechannel = 0;
+ int i;
+ afs_uint32 callNumber = *call->callNumber;
+
+ MUTEX_EXIT(&call->lock);
+
+ MUTEX_ENTER(&conn->conn_call_lock);
+
+ /* Are there any other call slots on this conn that we should try? Look for
+ * slots that are empty and are either non-busy, or were marked as busy
+ * longer than conn->secondsUntilDead seconds before this call started. */
+
+ for (i = 0; i < RX_MAXCALLS && !freechannel; i++) {
+ if (i == channel) {
+ /* only look at channels that aren't us */
+ continue;
+ }
+
+ if (conn->lastBusy[i]) {
+ /* if this channel looked busy too recently, don't look at it */
+ if (conn->lastBusy[i] >= call->startTime.sec) {
+ continue;
+ }
+ if (call->startTime.sec - conn->lastBusy[i] < conn->secondsUntilDead) {
+ continue;
+ }
+ }
+
+ if (conn->call[i]) {
+ struct rx_call *tcall = conn->call[i];
+ MUTEX_ENTER(&tcall->lock);
+ if (tcall->state == RX_STATE_DALLY) {
+ freechannel = 1;
+ }
+ MUTEX_EXIT(&tcall->lock);
+ } else {
+ freechannel = 1;
+ }
+ }
+
+ MUTEX_EXIT(&conn->conn_call_lock);
+
+ MUTEX_ENTER(&call->lock);
+
+ /* Since the call->lock and conn->conn_call_lock have been released it is
+ * possible that (1) the call may no longer be busy and/or (2) the call may
+ * have been reused by another waiting thread. Therefore, we must confirm
+ * that the call state has not changed when deciding whether or not to
+ * force this application thread to retry by forcing a Timeout error. */
+
+ if (freechannel && *call->callNumber == callNumber &&
+ (call->flags & RX_CALL_PEER_BUSY)) {
+ /* Since 'freechannel' is set, there exists another channel in this
+ * rx_conn that the application thread might be able to use. We know
+ * that we have the correct call since callNumber is unchanged, and we
+ * know that the call is still busy. So, set the call error state to
+ * rxi_busyChannelError so the application can retry the request,
+ * presumably on a less-busy call channel. */
+
+ rxi_CallError(call, rxi_busyChannelError);
+ }
+}
+
/* There are two packet tracing routines available for testing and monitoring
* Rx. One is called just after every packet is received and the other is
* called just before every packet is sent. Received packets, have had their
MUTEX_EXIT(&rx_refcnt_mutex);
return np; /* xmitting; drop packet */
}
- case RX_PACKET_TYPE_BUSY:
- /* XXXX */
- break;
+ case RX_PACKET_TYPE_BUSY: {
+ struct clock busyTime;
+ clock_NewTime();
+ clock_GetTime(&busyTime);
+
+ MUTEX_EXIT(&call->lock);
+
+ MUTEX_ENTER(&conn->conn_call_lock);
+ MUTEX_ENTER(&call->lock);
+ conn->lastBusy[call->channel] = busyTime.sec;
+ call->flags |= RX_CALL_PEER_BUSY;
+ MUTEX_EXIT(&call->lock);
+ MUTEX_EXIT(&conn->conn_call_lock);
+
+ MUTEX_ENTER(&rx_refcnt_mutex);
+ conn->refCount--;
+ MUTEX_EXIT(&rx_refcnt_mutex);
+ return np;
+ }
+
case RX_PACKET_TYPE_ACKALL:
/* All packets acknowledged, so we can drop all packets previously
* readied for sending */
}
#endif /* AFS_GLOBAL_RXLOCK_KERNEL */
rxi_ClearTransmitQueue(call, 0);
- rxevent_Cancel(call->keepAliveEvent, call, RX_CALL_REFCOUNT_ALIVE);
break;
default:
/* Should not reach here, unless the peer is broken: send an abort
* the packet will be delivered to the user before any get time is required
* (if not, then the time won't actually be re-evaluated here). */
call->lastReceiveTime = clock_Sec();
+ /* we've received a legit packet, so the channel is not busy */
+ call->flags &= ~RX_CALL_PEER_BUSY;
MUTEX_EXIT(&call->lock);
MUTEX_ENTER(&rx_refcnt_mutex);
conn->refCount--;
call->arrivalProc = (void (*)())0;
}
+ if (call->growMTUEvent)
+ rxevent_Cancel(call->growMTUEvent, call,
+ RX_CALL_REFCOUNT_ALIVE);
+
if (call->delayedAbortEvent) {
rxevent_Cancel(call->delayedAbortEvent, call, RX_CALL_REFCOUNT_ABORT);
packet = rxi_AllocPacket(RX_PACKET_CLASS_SPECIAL);
}
call->flags = 0;
+ if ((flags & RX_CALL_PEER_BUSY)) {
+ /* The call channel is still busy; resetting the call doesn't change
+ * that */
+ call->flags |= RX_CALL_PEER_BUSY;
+ }
+
rxi_ClearReceiveQueue(call);
/* why init the queue if you just emptied it? queue_Init(&call->rq); */
CALL_RELE(call, RX_CALL_REFCOUNT_RESEND);
MUTEX_EXIT(&rx_refcnt_mutex);
call->resendEvent = NULL;
+
+ if (rxi_busyChannelError && (call->flags & RX_CALL_PEER_BUSY)) {
+ rxi_CheckBusy(call);
+ }
+
if (queue_IsEmpty(&call->tq)) {
/* Nothing to do */
return;
rxevent_Cancel(call->resendEvent, call, RX_CALL_REFCOUNT_RESEND);
rxevent_Cancel(call->keepAliveEvent, call,
RX_CALL_REFCOUNT_ALIVE);
+ if (call->growMTUEvent)
+ rxevent_Cancel(call->growMTUEvent, call,
+ RX_CALL_REFCOUNT_ALIVE);
MUTEX_ENTER(&rx_refcnt_mutex);
if (call->refCount == 0) {
rxi_FreeCall(call, haveCTLock);
}
}
- if (hardDeadTime) {
+ if (conn->hardDeadTime) {
hardDeadTime = conn->hardDeadTime + fudgeFactor;
}
git://git.openafs.org / openafs.git / blobdiff