3 files changed, 92 insertions, 76 deletions

diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c
index 2e008efa735f..5bc84fbbeee5 100644
--- a/drivers/char/ipmi/ipmi_msghandler.c
+++ b/drivers/char/ipmi/ipmi_msghandler.c
@@ -534,15 +534,20 @@ struct ipmi_smi {
 	atomic_t         event_waiters;
 	unsigned int     ticks_to_req_ev;
 
+	spinlock_t       watch_lock; /* For dealing with watch stuff below. */
+
 	/* How many users are waiting for commands? */
-	atomic_t         command_waiters;
+	unsigned int     command_waiters;
 
 	/* How many users are waiting for watchdogs? */
-	atomic_t         watchdog_waiters;
+	unsigned int     watchdog_waiters;
+
+	/* How many users are waiting for message responses? */
+	unsigned int     response_waiters;
 
 	/*
 	 * Tells what the lower layer has last been asked to watch for,
-	 * messages and/or watchdogs.  Protected by xmit_msgs_lock.
+	 * messages and/or watchdogs.  Protected by watch_lock.
 	 */
 	unsigned int     last_watch_mask;
 
@@ -938,6 +943,64 @@ static void deliver_err_response(struct ipmi_smi *intf,
 	deliver_local_response(intf, msg);
 }
 
+static void smi_add_watch(struct ipmi_smi *intf, unsigned int flags)
+{
+	unsigned long iflags;
+
+	if (!intf->handlers->set_need_watch)
+		return;
+
+	spin_lock_irqsave(&intf->watch_lock, iflags);
+	if (flags & IPMI_WATCH_MASK_CHECK_MESSAGES)
+		intf->response_waiters++;
+
+	if (flags & IPMI_WATCH_MASK_CHECK_WATCHDOG)
+		intf->watchdog_waiters++;
+
+	if (flags & IPMI_WATCH_MASK_CHECK_COMMANDS)
+		intf->command_waiters++;
+
+	if ((intf->last_watch_mask & flags) != flags) {
+		intf->last_watch_mask |= flags;
+		intf->handlers->set_need_watch(intf->send_info,
+					       intf->last_watch_mask);
+	}
+	spin_unlock_irqrestore(&intf->watch_lock, iflags);
+}
+
+static void smi_remove_watch(struct ipmi_smi *intf, unsigned int flags)
+{
+	unsigned long iflags;
+
+	if (!intf->handlers->set_need_watch)
+		return;
+
+	spin_lock_irqsave(&intf->watch_lock, iflags);
+	if (flags & IPMI_WATCH_MASK_CHECK_MESSAGES)
+		intf->response_waiters--;
+
+	if (flags & IPMI_WATCH_MASK_CHECK_WATCHDOG)
+		intf->watchdog_waiters--;
+
+	if (flags & IPMI_WATCH_MASK_CHECK_COMMANDS)
+		intf->command_waiters--;
+
+	flags = 0;
+	if (intf->response_waiters)
+		flags |= IPMI_WATCH_MASK_CHECK_MESSAGES;
+	if (intf->watchdog_waiters)
+		flags |= IPMI_WATCH_MASK_CHECK_WATCHDOG;
+	if (intf->command_waiters)
+		flags |= IPMI_WATCH_MASK_CHECK_COMMANDS;
+
+	if (intf->last_watch_mask != flags) {
+		intf->last_watch_mask = flags;
+		intf->handlers->set_need_watch(intf->send_info,
+					       intf->last_watch_mask);
+	}
+	spin_unlock_irqrestore(&intf->watch_lock, iflags);
+}
+
 /*
  * Find the next sequence number not being used and add the given
  * message with the given timeout to the sequence table.  This must be
@@ -981,6 +1044,7 @@ static int intf_next_seq(struct ipmi_smi      *intf,
 		*seq = i;
 		*seqid = intf->seq_table[i].seqid;
 		intf->curr_seq = (i+1)%IPMI_IPMB_NUM_SEQ;
+		smi_add_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
 		need_waiter(intf);
 	} else {
 		rv = -EAGAIN;
@@ -1019,6 +1083,7 @@ static int intf_find_seq(struct ipmi_smi      *intf,
 				&& (ipmi_addr_equal(addr, &msg->addr))) {
 			*recv_msg = msg;
 			intf->seq_table[seq].inuse = 0;
+			smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
 			rv = 0;
 		}
 	}
@@ -1080,6 +1145,7 @@ static int intf_err_seq(struct ipmi_smi *intf,
 		struct seq_table *ent = &intf->seq_table[seq];
 
 		ent->inuse = 0;
+		smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
 		msg = ent->recv_msg;
 		rv = 0;
 	}
@@ -1091,30 +1157,6 @@ static int intf_err_seq(struct ipmi_smi *intf,
 	return rv;
 }
 
-/* Must be called with xmit_msgs_lock held. */
-static void smi_tell_to_watch(struct ipmi_smi *intf,
-			      unsigned int flags,
-			      struct ipmi_smi_msg *smi_msg)
-{
-	if (flags & IPMI_WATCH_MASK_CHECK_MESSAGES) {
-		if (!smi_msg)
-			return;
-
-		if (!smi_msg->needs_response)
-			return;
-	}
-
-	if (!intf->handlers->set_need_watch)
-		return;
-
-	if ((intf->last_watch_mask & flags) == flags)
-		return;
-
-	intf->last_watch_mask |= flags;
-	intf->handlers->set_need_watch(intf->send_info,
-				       intf->last_watch_mask);
-}
-
 int ipmi_create_user(unsigned int          if_num,
 		     const struct ipmi_user_hndl *handler,
 		     void                  *handler_data,
@@ -1175,12 +1217,9 @@ int ipmi_create_user(unsigned int          if_num,
 	spin_lock_irqsave(&intf->seq_lock, flags);
 	list_add_rcu(&new_user->link, &intf->users);
 	spin_unlock_irqrestore(&intf->seq_lock, flags);
-	if (handler->ipmi_watchdog_pretimeout) {
+	if (handler->ipmi_watchdog_pretimeout)
 		/* User wants pretimeouts, so make sure to watch for them. */
-		if (atomic_inc_return(&intf->watchdog_waiters) == 1)
-			smi_tell_to_watch(intf, IPMI_WATCH_MASK_CHECK_WATCHDOG,
-					  NULL);
-	}
+		smi_add_watch(intf, IPMI_WATCH_MASK_CHECK_WATCHDOG);
 	srcu_read_unlock(&ipmi_interfaces_srcu, index);
 	*user = new_user;
 	return 0;
@@ -1251,7 +1290,7 @@ static void _ipmi_destroy_user(struct ipmi_user *user)
 		user->handler->shutdown(user->handler_data);
 
 	if (user->handler->ipmi_watchdog_pretimeout)
-		atomic_dec(&intf->watchdog_waiters);
+		smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_WATCHDOG);
 
 	if (user->gets_events)
 		atomic_dec(&intf->event_waiters);
@@ -1264,6 +1303,7 @@ static void _ipmi_destroy_user(struct ipmi_user *user)
 		if (intf->seq_table[i].inuse
 		    && (intf->seq_table[i].recv_msg->user == user)) {
 			intf->seq_table[i].inuse = 0;
+			smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
 			ipmi_free_recv_msg(intf->seq_table[i].recv_msg);
 		}
 	}
@@ -1606,8 +1646,7 @@ int ipmi_register_for_cmd(struct ipmi_user *user,
 		goto out_unlock;
 	}
 
-	if (atomic_inc_return(&intf->command_waiters) == 1)
-		smi_tell_to_watch(intf, IPMI_WATCH_MASK_CHECK_COMMANDS, NULL);
+	smi_add_watch(intf, IPMI_WATCH_MASK_CHECK_COMMANDS);
 
 	list_add_rcu(&rcvr->link, &intf->cmd_rcvrs);
 
@@ -1657,7 +1696,7 @@ int ipmi_unregister_for_cmd(struct ipmi_user *user,
 	synchronize_rcu();
 	release_ipmi_user(user, index);
 	while (rcvrs) {
-		atomic_dec(&intf->command_waiters);
+		smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_COMMANDS);
 		rcvr = rcvrs;
 		rcvrs = rcvr->next;
 		kfree(rcvr);
@@ -1785,8 +1824,6 @@ static void smi_send(struct ipmi_smi *intf,
 		spin_lock_irqsave(&intf->xmit_msgs_lock, flags);
 	smi_msg = smi_add_send_msg(intf, smi_msg, priority);
 
-	smi_tell_to_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES, smi_msg);
-
 	if (!run_to_completion)
 		spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
 
@@ -1986,9 +2023,6 @@ static int i_ipmi_req_ipmb(struct ipmi_smi        *intf,
 				ipmb_seq, broadcast,
 				source_address, source_lun);
 
-		/* We will be getting a response in the BMC message queue. */
-		smi_msg->needs_response = true;
-
 		/*
 		 * Copy the message into the recv message data, so we
 		 * can retransmit it later if necessary.
@@ -2176,7 +2210,6 @@ static int i_ipmi_request(struct ipmi_user     *user,
 			goto out;
 		}
 	}
-	smi_msg->needs_response = false;
 
 	rcu_read_lock();
 	if (intf->in_shutdown) {
@@ -3390,9 +3423,8 @@ int ipmi_register_smi(const struct ipmi_smi_handlers *handlers,
 	INIT_LIST_HEAD(&intf->xmit_msgs);
 	INIT_LIST_HEAD(&intf->hp_xmit_msgs);
 	spin_lock_init(&intf->events_lock);
+	spin_lock_init(&intf->watch_lock);
 	atomic_set(&intf->event_waiters, 0);
-	atomic_set(&intf->watchdog_waiters, 0);
-	atomic_set(&intf->command_waiters, 0);
 	intf->ticks_to_req_ev = IPMI_REQUEST_EV_TIME;
 	INIT_LIST_HEAD(&intf->waiting_events);
 	intf->waiting_events_count = 0;
@@ -4408,8 +4440,6 @@ static void smi_recv_tasklet(unsigned long val)
 		}
 	}
 
-	smi_tell_to_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES, newmsg);
-
 	if (!run_to_completion)
 		spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
 	if (newmsg)
@@ -4537,7 +4567,7 @@ static void check_msg_timeout(struct ipmi_smi *intf, struct seq_table *ent,
 			      struct list_head *timeouts,
 			      unsigned long timeout_period,
 			      int slot, unsigned long *flags,
-			      unsigned int *watch_mask)
+			      bool *need_timer)
 {
 	struct ipmi_recv_msg *msg;
 
@@ -4549,13 +4579,14 @@ static void check_msg_timeout(struct ipmi_smi *intf, struct seq_table *ent,
 
 	if (timeout_period < ent->timeout) {
 		ent->timeout -= timeout_period;
-		*watch_mask |= IPMI_WATCH_MASK_CHECK_MESSAGES;
+		*need_timer = true;
 		return;
 	}
 
 	if (ent->retries_left == 0) {
 		/* The message has used all its retries. */
 		ent->inuse = 0;
+		smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
 		msg = ent->recv_msg;
 		list_add_tail(&msg->link, timeouts);
 		if (ent->broadcast)
@@ -4568,7 +4599,7 @@ static void check_msg_timeout(struct ipmi_smi *intf, struct seq_table *ent,
 		struct ipmi_smi_msg *smi_msg;
 		/* More retries, send again. */
 
-		*watch_mask |= IPMI_WATCH_MASK_CHECK_MESSAGES;
+		*need_timer = true;
 
 		/*
 		 * Start with the max timer, set to normal timer after
@@ -4613,20 +4644,20 @@ static void check_msg_timeout(struct ipmi_smi *intf, struct seq_table *ent,
 	}
 }
 
-static unsigned int ipmi_timeout_handler(struct ipmi_smi *intf,
-					 unsigned long timeout_period)
+static bool ipmi_timeout_handler(struct ipmi_smi *intf,
+				 unsigned long timeout_period)
 {
 	struct list_head     timeouts;
 	struct ipmi_recv_msg *msg, *msg2;
 	unsigned long        flags;
 	int                  i;
-	unsigned int         watch_mask = 0;
+	bool                 need_timer = false;
 
 	if (!intf->bmc_registered) {
 		kref_get(&intf->refcount);
 		if (!schedule_work(&intf->bmc_reg_work)) {
 			kref_put(&intf->refcount, intf_free);
-			watch_mask |= IPMI_WATCH_MASK_INTERNAL;
+			need_timer = true;
 		}
 	}
 
@@ -4646,7 +4677,7 @@ static unsigned int ipmi_timeout_handler(struct ipmi_smi *intf,
 	for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++)
 		check_msg_timeout(intf, &intf->seq_table[i],
 				  &timeouts, timeout_period, i,
-				  &flags, &watch_mask);
+				  &flags, &need_timer);
 	spin_unlock_irqrestore(&intf->seq_lock, flags);
 
 	list_for_each_entry_safe(msg, msg2, &timeouts, link)
@@ -4677,7 +4708,7 @@ static unsigned int ipmi_timeout_handler(struct ipmi_smi *intf,
 
 	tasklet_schedule(&intf->recv_tasklet);
 
-	return watch_mask;
+	return need_timer;
 }
 
 static void ipmi_request_event(struct ipmi_smi *intf)
@@ -4697,9 +4728,8 @@ static atomic_t stop_operation;
 static void ipmi_timeout(struct timer_list *unused)
 {
 	struct ipmi_smi *intf;
-	unsigned int watch_mask = 0;
+	bool need_timer = false;
 	int index;
-	unsigned long flags;
 
 	if (atomic_read(&stop_operation))
 		return;
@@ -4712,28 +4742,14 @@ static void ipmi_timeout(struct timer_list *unused)
 				ipmi_request_event(intf);
 				intf->ticks_to_req_ev = IPMI_REQUEST_EV_TIME;
 			}
-			watch_mask |= IPMI_WATCH_MASK_INTERNAL;
+			need_timer = true;
 		}
 
-		if (atomic_read(&intf->watchdog_waiters))
-			watch_mask |= IPMI_WATCH_MASK_CHECK_WATCHDOG;
-
-		if (atomic_read(&intf->command_waiters))
-			watch_mask |= IPMI_WATCH_MASK_CHECK_COMMANDS;
-
-		watch_mask |= ipmi_timeout_handler(intf, IPMI_TIMEOUT_TIME);
-
-		spin_lock_irqsave(&intf->xmit_msgs_lock, flags);
-		if (watch_mask != intf->last_watch_mask &&
-					intf->handlers->set_need_watch)
-			intf->handlers->set_need_watch(intf->send_info,
-						       watch_mask);
-		intf->last_watch_mask = watch_mask;
-		spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
+		need_timer |= ipmi_timeout_handler(intf, IPMI_TIMEOUT_TIME);
 	}
 	srcu_read_unlock(&ipmi_interfaces_srcu, index);
 
-	if (watch_mask)
+	if (need_timer)
 		mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
 }
 
diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
index c81c84a723b6..ae99d6a14789 100644
--- a/drivers/char/ipmi/ipmi_si_intf.c
+++ b/drivers/char/ipmi/ipmi_si_intf.c
@@ -1066,7 +1066,7 @@ static void set_need_watch(void *send_info, unsigned int watch_mask)
 	unsigned long flags;
 	int enable;
 
-	enable = !!(watch_mask & ~IPMI_WATCH_MASK_INTERNAL);
+	enable = !!watch_mask;
 
 	atomic_set(&smi_info->need_watch, enable);
 	spin_lock_irqsave(&smi_info->si_lock, flags);
diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c
index a1219af32105..e4abaa8e22bc 100644
--- a/drivers/char/ipmi/ipmi_ssif.c
+++ b/drivers/char/ipmi/ipmi_ssif.c
@@ -1129,7 +1129,7 @@ static void ssif_set_need_watch(void *send_info, unsigned int watch_mask)
 
 	if (watch_mask & IPMI_WATCH_MASK_CHECK_MESSAGES)
 		timeout = SSIF_WATCH_MSG_TIMEOUT;
-	else if (watch_mask & ~IPMI_WATCH_MASK_INTERNAL)
+	else if (watch_mask)
 		timeout = SSIF_WATCH_WATCHDOG_TIMEOUT;
 
 	flags = ipmi_ssif_lock_cond(ssif_info, &oflags);