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Diffstat (limited to 'arch/ia64/sn/kernel/xpc_channel.c')
-rw-r--r--arch/ia64/sn/kernel/xpc_channel.c329
1 files changed, 195 insertions, 134 deletions
diff --git a/arch/ia64/sn/kernel/xpc_channel.c b/arch/ia64/sn/kernel/xpc_channel.c
index 94698bea7be..abf4fc2a87b 100644
--- a/arch/ia64/sn/kernel/xpc_channel.c
+++ b/arch/ia64/sn/kernel/xpc_channel.c
@@ -57,6 +57,7 @@ xpc_initialize_channels(struct xpc_partition *part, partid_t partid)
spin_lock_init(&ch->lock);
sema_init(&ch->msg_to_pull_sema, 1); /* mutex */
+ sema_init(&ch->wdisconnect_sema, 0); /* event wait */
atomic_set(&ch->n_on_msg_allocate_wq, 0);
init_waitqueue_head(&ch->msg_allocate_wq);
@@ -166,6 +167,7 @@ xpc_setup_infrastructure(struct xpc_partition *part)
xpc_initialize_channels(part, partid);
atomic_set(&part->nchannels_active, 0);
+ atomic_set(&part->nchannels_engaged, 0);
/* local_IPI_amo were set to 0 by an earlier memset() */
@@ -555,8 +557,6 @@ xpc_allocate_msgqueues(struct xpc_channel *ch)
sema_init(&ch->notify_queue[i].sema, 0);
}
- sema_init(&ch->teardown_sema, 0); /* event wait */
-
spin_lock_irqsave(&ch->lock, irq_flags);
ch->flags |= XPC_C_SETUP;
spin_unlock_irqrestore(&ch->lock, irq_flags);
@@ -626,6 +626,55 @@ xpc_process_connect(struct xpc_channel *ch, unsigned long *irq_flags)
/*
+ * Notify those who wanted to be notified upon delivery of their message.
+ */
+static void
+xpc_notify_senders(struct xpc_channel *ch, enum xpc_retval reason, s64 put)
+{
+ struct xpc_notify *notify;
+ u8 notify_type;
+ s64 get = ch->w_remote_GP.get - 1;
+
+
+ while (++get < put && atomic_read(&ch->n_to_notify) > 0) {
+
+ notify = &ch->notify_queue[get % ch->local_nentries];
+
+ /*
+ * See if the notify entry indicates it was associated with
+ * a message who's sender wants to be notified. It is possible
+ * that it is, but someone else is doing or has done the
+ * notification.
+ */
+ notify_type = notify->type;
+ if (notify_type == 0 ||
+ cmpxchg(&notify->type, notify_type, 0) !=
+ notify_type) {
+ continue;
+ }
+
+ DBUG_ON(notify_type != XPC_N_CALL);
+
+ atomic_dec(&ch->n_to_notify);
+
+ if (notify->func != NULL) {
+ dev_dbg(xpc_chan, "notify->func() called, notify=0x%p, "
+ "msg_number=%ld, partid=%d, channel=%d\n",
+ (void *) notify, get, ch->partid, ch->number);
+
+ notify->func(reason, ch->partid, ch->number,
+ notify->key);
+
+ dev_dbg(xpc_chan, "notify->func() returned, "
+ "notify=0x%p, msg_number=%ld, partid=%d, "
+ "channel=%d\n", (void *) notify, get,
+ ch->partid, ch->number);
+ }
+ }
+}
+
+
+/*
* Free up message queues and other stuff that were allocated for the specified
* channel.
*
@@ -669,9 +718,6 @@ xpc_free_msgqueues(struct xpc_channel *ch)
ch->remote_msgqueue = NULL;
kfree(ch->notify_queue);
ch->notify_queue = NULL;
-
- /* in case someone is waiting for the teardown to complete */
- up(&ch->teardown_sema);
}
}
@@ -683,7 +729,7 @@ static void
xpc_process_disconnect(struct xpc_channel *ch, unsigned long *irq_flags)
{
struct xpc_partition *part = &xpc_partitions[ch->partid];
- u32 ch_flags = ch->flags;
+ u32 channel_was_connected = (ch->flags & XPC_C_WASCONNECTED);
DBUG_ON(!spin_is_locked(&ch->lock));
@@ -701,12 +747,13 @@ xpc_process_disconnect(struct xpc_channel *ch, unsigned long *irq_flags)
}
DBUG_ON(atomic_read(&ch->kthreads_assigned) != 0);
- /* it's now safe to free the channel's message queues */
-
- xpc_free_msgqueues(ch);
- DBUG_ON(ch->flags & XPC_C_SETUP);
+ if (part->act_state == XPC_P_DEACTIVATING) {
+ /* can't proceed until the other side disengages from us */
+ if (xpc_partition_engaged(1UL << ch->partid)) {
+ return;
+ }
- if (part->act_state != XPC_P_DEACTIVATING) {
+ } else {
/* as long as the other side is up do the full protocol */
@@ -724,16 +771,42 @@ xpc_process_disconnect(struct xpc_channel *ch, unsigned long *irq_flags)
}
}
+ /* wake those waiting for notify completion */
+ if (atomic_read(&ch->n_to_notify) > 0) {
+ /* >>> we do callout while holding ch->lock */
+ xpc_notify_senders(ch, ch->reason, ch->w_local_GP.put);
+ }
+
/* both sides are disconnected now */
- ch->flags = XPC_C_DISCONNECTED; /* clear all flags, but this one */
+ /* it's now safe to free the channel's message queues */
+ xpc_free_msgqueues(ch);
+
+ /* mark disconnected, clear all other flags except XPC_C_WDISCONNECT */
+ ch->flags = (XPC_C_DISCONNECTED | (ch->flags & XPC_C_WDISCONNECT));
atomic_dec(&part->nchannels_active);
- if (ch_flags & XPC_C_WASCONNECTED) {
+ if (channel_was_connected) {
dev_info(xpc_chan, "channel %d to partition %d disconnected, "
"reason=%d\n", ch->number, ch->partid, ch->reason);
}
+
+ if (ch->flags & XPC_C_WDISCONNECT) {
+ spin_unlock_irqrestore(&ch->lock, *irq_flags);
+ up(&ch->wdisconnect_sema);
+ spin_lock_irqsave(&ch->lock, *irq_flags);
+
+ } else if (ch->delayed_IPI_flags) {
+ if (part->act_state != XPC_P_DEACTIVATING) {
+ /* time to take action on any delayed IPI flags */
+ spin_lock(&part->IPI_lock);
+ XPC_SET_IPI_FLAGS(part->local_IPI_amo, ch->number,
+ ch->delayed_IPI_flags);
+ spin_unlock(&part->IPI_lock);
+ }
+ ch->delayed_IPI_flags = 0;
+ }
}
@@ -754,6 +827,19 @@ xpc_process_openclose_IPI(struct xpc_partition *part, int ch_number,
spin_lock_irqsave(&ch->lock, irq_flags);
+again:
+
+ if ((ch->flags & XPC_C_DISCONNECTED) &&
+ (ch->flags & XPC_C_WDISCONNECT)) {
+ /*
+ * Delay processing IPI flags until thread waiting disconnect
+ * has had a chance to see that the channel is disconnected.
+ */
+ ch->delayed_IPI_flags |= IPI_flags;
+ spin_unlock_irqrestore(&ch->lock, irq_flags);
+ return;
+ }
+
if (IPI_flags & XPC_IPI_CLOSEREQUEST) {
@@ -764,7 +850,7 @@ xpc_process_openclose_IPI(struct xpc_partition *part, int ch_number,
/*
* If RCLOSEREQUEST is set, we're probably waiting for
* RCLOSEREPLY. We should find it and a ROPENREQUEST packed
- * with this RCLOSEQREUQEST in the IPI_flags.
+ * with this RCLOSEREQUEST in the IPI_flags.
*/
if (ch->flags & XPC_C_RCLOSEREQUEST) {
@@ -779,14 +865,22 @@ xpc_process_openclose_IPI(struct xpc_partition *part, int ch_number,
/* both sides have finished disconnecting */
xpc_process_disconnect(ch, &irq_flags);
+ DBUG_ON(!(ch->flags & XPC_C_DISCONNECTED));
+ goto again;
}
if (ch->flags & XPC_C_DISCONNECTED) {
- // >>> explain this section
-
if (!(IPI_flags & XPC_IPI_OPENREQUEST)) {
- DBUG_ON(part->act_state !=
- XPC_P_DEACTIVATING);
+ if ((XPC_GET_IPI_FLAGS(part->local_IPI_amo,
+ ch_number) & XPC_IPI_OPENREQUEST)) {
+
+ DBUG_ON(ch->delayed_IPI_flags != 0);
+ spin_lock(&part->IPI_lock);
+ XPC_SET_IPI_FLAGS(part->local_IPI_amo,
+ ch_number,
+ XPC_IPI_CLOSEREQUEST);
+ spin_unlock(&part->IPI_lock);
+ }
spin_unlock_irqrestore(&ch->lock, irq_flags);
return;
}
@@ -816,9 +910,13 @@ xpc_process_openclose_IPI(struct xpc_partition *part, int ch_number,
}
XPC_DISCONNECT_CHANNEL(ch, reason, &irq_flags);
- } else {
- xpc_process_disconnect(ch, &irq_flags);
+
+ DBUG_ON(IPI_flags & XPC_IPI_CLOSEREPLY);
+ spin_unlock_irqrestore(&ch->lock, irq_flags);
+ return;
}
+
+ xpc_process_disconnect(ch, &irq_flags);
}
@@ -834,7 +932,20 @@ xpc_process_openclose_IPI(struct xpc_partition *part, int ch_number,
}
DBUG_ON(!(ch->flags & XPC_C_CLOSEREQUEST));
- DBUG_ON(!(ch->flags & XPC_C_RCLOSEREQUEST));
+
+ if (!(ch->flags & XPC_C_RCLOSEREQUEST)) {
+ if ((XPC_GET_IPI_FLAGS(part->local_IPI_amo, ch_number)
+ & XPC_IPI_CLOSEREQUEST)) {
+
+ DBUG_ON(ch->delayed_IPI_flags != 0);
+ spin_lock(&part->IPI_lock);
+ XPC_SET_IPI_FLAGS(part->local_IPI_amo,
+ ch_number, XPC_IPI_CLOSEREPLY);
+ spin_unlock(&part->IPI_lock);
+ }
+ spin_unlock_irqrestore(&ch->lock, irq_flags);
+ return;
+ }
ch->flags |= XPC_C_RCLOSEREPLY;
@@ -852,8 +963,14 @@ xpc_process_openclose_IPI(struct xpc_partition *part, int ch_number,
"channel=%d\n", args->msg_size, args->local_nentries,
ch->partid, ch->number);
- if ((ch->flags & XPC_C_DISCONNECTING) ||
- part->act_state == XPC_P_DEACTIVATING) {
+ if (part->act_state == XPC_P_DEACTIVATING ||
+ (ch->flags & XPC_C_ROPENREQUEST)) {
+ spin_unlock_irqrestore(&ch->lock, irq_flags);
+ return;
+ }
+
+ if (ch->flags & (XPC_C_DISCONNECTING | XPC_C_WDISCONNECT)) {
+ ch->delayed_IPI_flags |= XPC_IPI_OPENREQUEST;
spin_unlock_irqrestore(&ch->lock, irq_flags);
return;
}
@@ -867,8 +984,11 @@ xpc_process_openclose_IPI(struct xpc_partition *part, int ch_number,
* msg_size = size of channel's messages in bytes
* local_nentries = remote partition's local_nentries
*/
- DBUG_ON(args->msg_size == 0);
- DBUG_ON(args->local_nentries == 0);
+ if (args->msg_size == 0 || args->local_nentries == 0) {
+ /* assume OPENREQUEST was delayed by mistake */
+ spin_unlock_irqrestore(&ch->lock, irq_flags);
+ return;
+ }
ch->flags |= (XPC_C_ROPENREQUEST | XPC_C_CONNECTING);
ch->remote_nentries = args->local_nentries;
@@ -906,7 +1026,13 @@ xpc_process_openclose_IPI(struct xpc_partition *part, int ch_number,
spin_unlock_irqrestore(&ch->lock, irq_flags);
return;
}
- DBUG_ON(!(ch->flags & XPC_C_OPENREQUEST));
+ if (!(ch->flags & XPC_C_OPENREQUEST)) {
+ XPC_DISCONNECT_CHANNEL(ch, xpcOpenCloseError,
+ &irq_flags);
+ spin_unlock_irqrestore(&ch->lock, irq_flags);
+ return;
+ }
+
DBUG_ON(!(ch->flags & XPC_C_ROPENREQUEST));
DBUG_ON(ch->flags & XPC_C_CONNECTED);
@@ -960,8 +1086,8 @@ xpc_connect_channel(struct xpc_channel *ch)
struct xpc_registration *registration = &xpc_registrations[ch->number];
- if (down_interruptible(&registration->sema) != 0) {
- return xpcInterrupted;
+ if (down_trylock(&registration->sema) != 0) {
+ return xpcRetry;
}
if (!XPC_CHANNEL_REGISTERED(ch->number)) {
@@ -1040,55 +1166,6 @@ xpc_connect_channel(struct xpc_channel *ch)
/*
- * Notify those who wanted to be notified upon delivery of their message.
- */
-static void
-xpc_notify_senders(struct xpc_channel *ch, enum xpc_retval reason, s64 put)
-{
- struct xpc_notify *notify;
- u8 notify_type;
- s64 get = ch->w_remote_GP.get - 1;
-
-
- while (++get < put && atomic_read(&ch->n_to_notify) > 0) {
-
- notify = &ch->notify_queue[get % ch->local_nentries];
-
- /*
- * See if the notify entry indicates it was associated with
- * a message who's sender wants to be notified. It is possible
- * that it is, but someone else is doing or has done the
- * notification.
- */
- notify_type = notify->type;
- if (notify_type == 0 ||
- cmpxchg(&notify->type, notify_type, 0) !=
- notify_type) {
- continue;
- }
-
- DBUG_ON(notify_type != XPC_N_CALL);
-
- atomic_dec(&ch->n_to_notify);
-
- if (notify->func != NULL) {
- dev_dbg(xpc_chan, "notify->func() called, notify=0x%p, "
- "msg_number=%ld, partid=%d, channel=%d\n",
- (void *) notify, get, ch->partid, ch->number);
-
- notify->func(reason, ch->partid, ch->number,
- notify->key);
-
- dev_dbg(xpc_chan, "notify->func() returned, "
- "notify=0x%p, msg_number=%ld, partid=%d, "
- "channel=%d\n", (void *) notify, get,
- ch->partid, ch->number);
- }
- }
-}
-
-
-/*
* Clear some of the msg flags in the local message queue.
*/
static inline void
@@ -1240,6 +1317,7 @@ xpc_process_channel_activity(struct xpc_partition *part)
u64 IPI_amo, IPI_flags;
struct xpc_channel *ch;
int ch_number;
+ u32 ch_flags;
IPI_amo = xpc_get_IPI_flags(part);
@@ -1266,8 +1344,9 @@ xpc_process_channel_activity(struct xpc_partition *part)
xpc_process_openclose_IPI(part, ch_number, IPI_flags);
}
+ ch_flags = ch->flags; /* need an atomic snapshot of flags */
- if (ch->flags & XPC_C_DISCONNECTING) {
+ if (ch_flags & XPC_C_DISCONNECTING) {
spin_lock_irqsave(&ch->lock, irq_flags);
xpc_process_disconnect(ch, &irq_flags);
spin_unlock_irqrestore(&ch->lock, irq_flags);
@@ -1278,9 +1357,9 @@ xpc_process_channel_activity(struct xpc_partition *part)
continue;
}
- if (!(ch->flags & XPC_C_CONNECTED)) {
- if (!(ch->flags & XPC_C_OPENREQUEST)) {
- DBUG_ON(ch->flags & XPC_C_SETUP);
+ if (!(ch_flags & XPC_C_CONNECTED)) {
+ if (!(ch_flags & XPC_C_OPENREQUEST)) {
+ DBUG_ON(ch_flags & XPC_C_SETUP);
(void) xpc_connect_channel(ch);
} else {
spin_lock_irqsave(&ch->lock, irq_flags);
@@ -1305,8 +1384,8 @@ xpc_process_channel_activity(struct xpc_partition *part)
/*
- * XPC's heartbeat code calls this function to inform XPC that a partition has
- * gone down. XPC responds by tearing down the XPartition Communication
+ * XPC's heartbeat code calls this function to inform XPC that a partition is
+ * going down. XPC responds by tearing down the XPartition Communication
* infrastructure used for the just downed partition.
*
* XPC's heartbeat code will never call this function and xpc_partition_up()
@@ -1314,7 +1393,7 @@ xpc_process_channel_activity(struct xpc_partition *part)
* at the same time.
*/
void
-xpc_partition_down(struct xpc_partition *part, enum xpc_retval reason)
+xpc_partition_going_down(struct xpc_partition *part, enum xpc_retval reason)
{
unsigned long irq_flags;
int ch_number;
@@ -1330,12 +1409,11 @@ xpc_partition_down(struct xpc_partition *part, enum xpc_retval reason)
}
- /* disconnect all channels associated with the downed partition */
+ /* disconnect channels associated with the partition going down */
for (ch_number = 0; ch_number < part->nchannels; ch_number++) {
ch = &part->channels[ch_number];
-
xpc_msgqueue_ref(ch);
spin_lock_irqsave(&ch->lock, irq_flags);
@@ -1370,6 +1448,7 @@ xpc_teardown_infrastructure(struct xpc_partition *part)
* this partition.
*/
+ DBUG_ON(atomic_read(&part->nchannels_engaged) != 0);
DBUG_ON(atomic_read(&part->nchannels_active) != 0);
DBUG_ON(part->setup_state != XPC_P_SETUP);
part->setup_state = XPC_P_WTEARDOWN;
@@ -1428,19 +1507,11 @@ xpc_initiate_connect(int ch_number)
if (xpc_part_ref(part)) {
ch = &part->channels[ch_number];
- if (!(ch->flags & XPC_C_DISCONNECTING)) {
- DBUG_ON(ch->flags & XPC_C_OPENREQUEST);
- DBUG_ON(ch->flags & XPC_C_CONNECTED);
- DBUG_ON(ch->flags & XPC_C_SETUP);
-
- /*
- * Initiate the establishment of a connection
- * on the newly registered channel to the
- * remote partition.
- */
- xpc_wakeup_channel_mgr(part);
- }
-
+ /*
+ * Initiate the establishment of a connection on the
+ * newly registered channel to the remote partition.
+ */
+ xpc_wakeup_channel_mgr(part);
xpc_part_deref(part);
}
}
@@ -1450,9 +1521,6 @@ xpc_initiate_connect(int ch_number)
void
xpc_connected_callout(struct xpc_channel *ch)
{
- unsigned long irq_flags;
-
-
/* let the registerer know that a connection has been established */
if (ch->func != NULL) {
@@ -1465,10 +1533,6 @@ xpc_connected_callout(struct xpc_channel *ch)
dev_dbg(xpc_chan, "ch->func() returned, reason=xpcConnected, "
"partid=%d, channel=%d\n", ch->partid, ch->number);
}
-
- spin_lock_irqsave(&ch->lock, irq_flags);
- ch->flags |= XPC_C_CONNECTCALLOUT;
- spin_unlock_irqrestore(&ch->lock, irq_flags);
}
@@ -1506,8 +1570,12 @@ xpc_initiate_disconnect(int ch_number)
spin_lock_irqsave(&ch->lock, irq_flags);
- XPC_DISCONNECT_CHANNEL(ch, xpcUnregistering,
+ if (!(ch->flags & XPC_C_DISCONNECTED)) {
+ ch->flags |= XPC_C_WDISCONNECT;
+
+ XPC_DISCONNECT_CHANNEL(ch, xpcUnregistering,
&irq_flags);
+ }
spin_unlock_irqrestore(&ch->lock, irq_flags);
@@ -1523,8 +1591,9 @@ xpc_initiate_disconnect(int ch_number)
/*
* To disconnect a channel, and reflect it back to all who may be waiting.
*
- * >>> An OPEN is not allowed until XPC_C_DISCONNECTING is cleared by
- * >>> xpc_free_msgqueues().
+ * An OPEN is not allowed until XPC_C_DISCONNECTING is cleared by
+ * xpc_process_disconnect(), and if set, XPC_C_WDISCONNECT is cleared by
+ * xpc_disconnect_wait().
*
* THE CHANNEL IS TO BE LOCKED BY THE CALLER AND WILL REMAIN LOCKED UPON RETURN.
*/
@@ -1532,7 +1601,7 @@ void
xpc_disconnect_channel(const int line, struct xpc_channel *ch,
enum xpc_retval reason, unsigned long *irq_flags)
{
- u32 flags;
+ u32 channel_was_connected = (ch->flags & XPC_C_CONNECTED);
DBUG_ON(!spin_is_locked(&ch->lock));
@@ -1547,61 +1616,53 @@ xpc_disconnect_channel(const int line, struct xpc_channel *ch,
XPC_SET_REASON(ch, reason, line);
- flags = ch->flags;
+ ch->flags |= (XPC_C_CLOSEREQUEST | XPC_C_DISCONNECTING);
/* some of these may not have been set */
ch->flags &= ~(XPC_C_OPENREQUEST | XPC_C_OPENREPLY |
XPC_C_ROPENREQUEST | XPC_C_ROPENREPLY |
XPC_C_CONNECTING | XPC_C_CONNECTED);
- ch->flags |= (XPC_C_CLOSEREQUEST | XPC_C_DISCONNECTING);
xpc_IPI_send_closerequest(ch, irq_flags);
- if (flags & XPC_C_CONNECTED) {
+ if (channel_was_connected) {
ch->flags |= XPC_C_WASCONNECTED;
}
+ spin_unlock_irqrestore(&ch->lock, *irq_flags);
+
+ /* wake all idle kthreads so they can exit */
if (atomic_read(&ch->kthreads_idle) > 0) {
- /* wake all idle kthreads so they can exit */
wake_up_all(&ch->idle_wq);
}
- spin_unlock_irqrestore(&ch->lock, *irq_flags);
-
-
/* wake those waiting to allocate an entry from the local msg queue */
-
if (atomic_read(&ch->n_on_msg_allocate_wq) > 0) {
wake_up(&ch->msg_allocate_wq);
}
- /* wake those waiting for notify completion */
-
- if (atomic_read(&ch->n_to_notify) > 0) {
- xpc_notify_senders(ch, reason, ch->w_local_GP.put);
- }
-
spin_lock_irqsave(&ch->lock, *irq_flags);
}
void
-xpc_disconnected_callout(struct xpc_channel *ch)
+xpc_disconnecting_callout(struct xpc_channel *ch)
{
/*
- * Let the channel's registerer know that the channel is now
+ * Let the channel's registerer know that the channel is being
* disconnected. We don't want to do this if the registerer was never
- * informed of a connection being made, unless the disconnect was for
- * abnormal reasons.
+ * informed of a connection being made.
*/
if (ch->func != NULL) {
- dev_dbg(xpc_chan, "ch->func() called, reason=%d, partid=%d, "
- "channel=%d\n", ch->reason, ch->partid, ch->number);
+ dev_dbg(xpc_chan, "ch->func() called, reason=xpcDisconnecting,"
+ " partid=%d, channel=%d\n", ch->partid, ch->number);
- ch->func(ch->reason, ch->partid, ch->number, NULL, ch->key);
+ ch->func(xpcDisconnecting, ch->partid, ch->number, NULL,
+ ch->key);
- dev_dbg(xpc_chan, "ch->func() returned, reason=%d, partid=%d, "
- "channel=%d\n", ch->reason, ch->partid, ch->number);
+ dev_dbg(xpc_chan, "ch->func() returned, reason="
+ "xpcDisconnecting, partid=%d, channel=%d\n",
+ ch->partid, ch->number);
}
}
@@ -1848,7 +1909,7 @@ xpc_send_msg(struct xpc_channel *ch, struct xpc_msg *msg, u8 notify_type,
xpc_notify_func func, void *key)
{
enum xpc_retval ret = xpcSuccess;
- struct xpc_notify *notify = NULL; // >>> to keep the compiler happy!!
+ struct xpc_notify *notify = notify;
s64 put, msg_number = msg->number;