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path: root/drivers/char/ipmi/ipmi_msghandler.c
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Diffstat (limited to 'drivers/char/ipmi/ipmi_msghandler.c')
-rw-r--r--drivers/char/ipmi/ipmi_msghandler.c239
1 files changed, 144 insertions, 95 deletions
diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c
index ec4e10fcf1a5..e6db9381b2c7 100644
--- a/drivers/char/ipmi/ipmi_msghandler.c
+++ b/drivers/char/ipmi/ipmi_msghandler.c
@@ -55,6 +55,7 @@ static struct ipmi_recv_msg *ipmi_alloc_recv_msg(void);
static int ipmi_init_msghandler(void);
static void smi_recv_tasklet(unsigned long);
static void handle_new_recv_msgs(ipmi_smi_t intf);
+static void need_waiter(ipmi_smi_t intf);
static int initialized;
@@ -73,14 +74,28 @@ static struct proc_dir_entry *proc_ipmi_root;
*/
#define MAX_MSG_TIMEOUT 60000
+/* Call every ~1000 ms. */
+#define IPMI_TIMEOUT_TIME 1000
+
+/* How many jiffies does it take to get to the timeout time. */
+#define IPMI_TIMEOUT_JIFFIES ((IPMI_TIMEOUT_TIME * HZ) / 1000)
+
+/*
+ * Request events from the queue every second (this is the number of
+ * IPMI_TIMEOUT_TIMES between event requests). Hopefully, in the
+ * future, IPMI will add a way to know immediately if an event is in
+ * the queue and this silliness can go away.
+ */
+#define IPMI_REQUEST_EV_TIME (1000 / (IPMI_TIMEOUT_TIME))
+
/*
* The main "user" data structure.
*/
struct ipmi_user {
struct list_head link;
- /* Set to "0" when the user is destroyed. */
- int valid;
+ /* Set to false when the user is destroyed. */
+ bool valid;
struct kref refcount;
@@ -92,7 +107,7 @@ struct ipmi_user {
ipmi_smi_t intf;
/* Does this interface receive IPMI events? */
- int gets_events;
+ bool gets_events;
};
struct cmd_rcvr {
@@ -383,6 +398,9 @@ struct ipmi_smi {
unsigned int waiting_events_count; /* How many events in queue? */
char delivering_events;
char event_msg_printed;
+ atomic_t event_waiters;
+ unsigned int ticks_to_req_ev;
+ int last_needs_timer;
/*
* The event receiver for my BMC, only really used at panic
@@ -395,7 +413,7 @@ struct ipmi_smi {
/* For handling of maintenance mode. */
int maintenance_mode;
- int maintenance_mode_enable;
+ bool maintenance_mode_enable;
int auto_maintenance_timeout;
spinlock_t maintenance_mode_lock; /* Used in a timer... */
@@ -451,7 +469,6 @@ static DEFINE_MUTEX(ipmi_interfaces_mutex);
static LIST_HEAD(smi_watchers);
static DEFINE_MUTEX(smi_watchers_mutex);
-
#define ipmi_inc_stat(intf, stat) \
atomic_inc(&(intf)->stats[IPMI_STAT_ ## stat])
#define ipmi_get_stat(intf, stat) \
@@ -772,6 +789,7 @@ static int intf_next_seq(ipmi_smi_t intf,
*seq = i;
*seqid = intf->seq_table[i].seqid;
intf->curr_seq = (i+1)%IPMI_IPMB_NUM_SEQ;
+ need_waiter(intf);
} else {
rv = -EAGAIN;
}
@@ -941,7 +959,7 @@ int ipmi_create_user(unsigned int if_num,
new_user->handler = handler;
new_user->handler_data = handler_data;
new_user->intf = intf;
- new_user->gets_events = 0;
+ new_user->gets_events = false;
if (!try_module_get(intf->handlers->owner)) {
rv = -ENODEV;
@@ -962,10 +980,15 @@ int ipmi_create_user(unsigned int if_num,
*/
mutex_unlock(&ipmi_interfaces_mutex);
- new_user->valid = 1;
+ new_user->valid = true;
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) {
+ /* User wants pretimeouts, so make sure to watch for them. */
+ if (atomic_inc_return(&intf->event_waiters) == 1)
+ need_waiter(intf);
+ }
*user = new_user;
return 0;
@@ -1019,7 +1042,13 @@ int ipmi_destroy_user(ipmi_user_t user)
struct cmd_rcvr *rcvr;
struct cmd_rcvr *rcvrs = NULL;
- user->valid = 0;
+ user->valid = false;
+
+ if (user->handler->ipmi_watchdog_pretimeout)
+ atomic_dec(&intf->event_waiters);
+
+ if (user->gets_events)
+ atomic_dec(&intf->event_waiters);
/* Remove the user from the interface's sequence table. */
spin_lock_irqsave(&intf->seq_lock, flags);
@@ -1155,25 +1184,23 @@ int ipmi_set_maintenance_mode(ipmi_user_t user, int mode)
if (intf->maintenance_mode != mode) {
switch (mode) {
case IPMI_MAINTENANCE_MODE_AUTO:
- intf->maintenance_mode = mode;
intf->maintenance_mode_enable
= (intf->auto_maintenance_timeout > 0);
break;
case IPMI_MAINTENANCE_MODE_OFF:
- intf->maintenance_mode = mode;
- intf->maintenance_mode_enable = 0;
+ intf->maintenance_mode_enable = false;
break;
case IPMI_MAINTENANCE_MODE_ON:
- intf->maintenance_mode = mode;
- intf->maintenance_mode_enable = 1;
+ intf->maintenance_mode_enable = true;
break;
default:
rv = -EINVAL;
goto out_unlock;
}
+ intf->maintenance_mode = mode;
maintenance_mode_update(intf);
}
@@ -1184,7 +1211,7 @@ int ipmi_set_maintenance_mode(ipmi_user_t user, int mode)
}
EXPORT_SYMBOL(ipmi_set_maintenance_mode);
-int ipmi_set_gets_events(ipmi_user_t user, int val)
+int ipmi_set_gets_events(ipmi_user_t user, bool val)
{
unsigned long flags;
ipmi_smi_t intf = user->intf;
@@ -1194,8 +1221,18 @@ int ipmi_set_gets_events(ipmi_user_t user, int val)
INIT_LIST_HEAD(&msgs);
spin_lock_irqsave(&intf->events_lock, flags);
+ if (user->gets_events == val)
+ goto out;
+
user->gets_events = val;
+ if (val) {
+ if (atomic_inc_return(&intf->event_waiters) == 1)
+ need_waiter(intf);
+ } else {
+ atomic_dec(&intf->event_waiters);
+ }
+
if (intf->delivering_events)
/*
* Another thread is delivering events for this, so
@@ -1289,6 +1326,9 @@ int ipmi_register_for_cmd(ipmi_user_t user,
goto out_unlock;
}
+ if (atomic_inc_return(&intf->event_waiters) == 1)
+ need_waiter(intf);
+
list_add_rcu(&rcvr->link, &intf->cmd_rcvrs);
out_unlock:
@@ -1330,6 +1370,7 @@ int ipmi_unregister_for_cmd(ipmi_user_t user,
mutex_unlock(&intf->cmd_rcvrs_mutex);
synchronize_rcu();
while (rcvrs) {
+ atomic_dec(&intf->event_waiters);
rcvr = rcvrs;
rcvrs = rcvr->next;
kfree(rcvr);
@@ -1535,7 +1576,7 @@ static int i_ipmi_request(ipmi_user_t user,
= IPMI_MAINTENANCE_MODE_TIMEOUT;
if (!intf->maintenance_mode
&& !intf->maintenance_mode_enable) {
- intf->maintenance_mode_enable = 1;
+ intf->maintenance_mode_enable = true;
maintenance_mode_update(intf);
}
spin_unlock_irqrestore(&intf->maintenance_mode_lock,
@@ -2876,6 +2917,8 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers,
(unsigned long) intf);
atomic_set(&intf->watchdog_pretimeouts_to_deliver, 0);
spin_lock_init(&intf->events_lock);
+ atomic_set(&intf->event_waiters, 0);
+ intf->ticks_to_req_ev = IPMI_REQUEST_EV_TIME;
INIT_LIST_HEAD(&intf->waiting_events);
intf->waiting_events_count = 0;
mutex_init(&intf->cmd_rcvrs_mutex);
@@ -3965,7 +4008,8 @@ smi_from_recv_msg(ipmi_smi_t intf, struct ipmi_recv_msg *recv_msg,
static void check_msg_timeout(ipmi_smi_t intf, struct seq_table *ent,
struct list_head *timeouts, long timeout_period,
- int slot, unsigned long *flags)
+ int slot, unsigned long *flags,
+ unsigned int *waiting_msgs)
{
struct ipmi_recv_msg *msg;
struct ipmi_smi_handlers *handlers;
@@ -3977,8 +4021,10 @@ static void check_msg_timeout(ipmi_smi_t intf, struct seq_table *ent,
return;
ent->timeout -= timeout_period;
- if (ent->timeout > 0)
+ if (ent->timeout > 0) {
+ (*waiting_msgs)++;
return;
+ }
if (ent->retries_left == 0) {
/* The message has used all its retries. */
@@ -3995,6 +4041,8 @@ static void check_msg_timeout(ipmi_smi_t intf, struct seq_table *ent,
struct ipmi_smi_msg *smi_msg;
/* More retries, send again. */
+ (*waiting_msgs)++;
+
/*
* Start with the max timer, set to normal timer after
* the message is sent.
@@ -4040,117 +4088,118 @@ static void check_msg_timeout(ipmi_smi_t intf, struct seq_table *ent,
}
}
-static void ipmi_timeout_handler(long timeout_period)
+static unsigned int ipmi_timeout_handler(ipmi_smi_t intf, long timeout_period)
{
- ipmi_smi_t intf;
struct list_head timeouts;
struct ipmi_recv_msg *msg, *msg2;
unsigned long flags;
int i;
+ unsigned int waiting_msgs = 0;
- rcu_read_lock();
- list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
- tasklet_schedule(&intf->recv_tasklet);
-
- /*
- * Go through the seq table and find any messages that
- * have timed out, putting them in the timeouts
- * list.
- */
- INIT_LIST_HEAD(&timeouts);
- spin_lock_irqsave(&intf->seq_lock, flags);
- for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++)
- check_msg_timeout(intf, &(intf->seq_table[i]),
- &timeouts, timeout_period, i,
- &flags);
- spin_unlock_irqrestore(&intf->seq_lock, flags);
+ /*
+ * Go through the seq table and find any messages that
+ * have timed out, putting them in the timeouts
+ * list.
+ */
+ INIT_LIST_HEAD(&timeouts);
+ spin_lock_irqsave(&intf->seq_lock, flags);
+ for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++)
+ check_msg_timeout(intf, &(intf->seq_table[i]),
+ &timeouts, timeout_period, i,
+ &flags, &waiting_msgs);
+ spin_unlock_irqrestore(&intf->seq_lock, flags);
- list_for_each_entry_safe(msg, msg2, &timeouts, link)
- deliver_err_response(msg, IPMI_TIMEOUT_COMPLETION_CODE);
+ list_for_each_entry_safe(msg, msg2, &timeouts, link)
+ deliver_err_response(msg, IPMI_TIMEOUT_COMPLETION_CODE);
- /*
- * Maintenance mode handling. Check the timeout
- * optimistically before we claim the lock. It may
- * mean a timeout gets missed occasionally, but that
- * only means the timeout gets extended by one period
- * in that case. No big deal, and it avoids the lock
- * most of the time.
- */
+ /*
+ * Maintenance mode handling. Check the timeout
+ * optimistically before we claim the lock. It may
+ * mean a timeout gets missed occasionally, but that
+ * only means the timeout gets extended by one period
+ * in that case. No big deal, and it avoids the lock
+ * most of the time.
+ */
+ if (intf->auto_maintenance_timeout > 0) {
+ spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
if (intf->auto_maintenance_timeout > 0) {
- spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
- if (intf->auto_maintenance_timeout > 0) {
- intf->auto_maintenance_timeout
- -= timeout_period;
- if (!intf->maintenance_mode
- && (intf->auto_maintenance_timeout <= 0)) {
- intf->maintenance_mode_enable = 0;
- maintenance_mode_update(intf);
- }
+ intf->auto_maintenance_timeout
+ -= timeout_period;
+ if (!intf->maintenance_mode
+ && (intf->auto_maintenance_timeout <= 0)) {
+ intf->maintenance_mode_enable = false;
+ maintenance_mode_update(intf);
}
- spin_unlock_irqrestore(&intf->maintenance_mode_lock,
- flags);
}
+ spin_unlock_irqrestore(&intf->maintenance_mode_lock,
+ flags);
}
- rcu_read_unlock();
+
+ tasklet_schedule(&intf->recv_tasklet);
+
+ return waiting_msgs;
}
-static void ipmi_request_event(void)
+static void ipmi_request_event(ipmi_smi_t intf)
{
- ipmi_smi_t intf;
struct ipmi_smi_handlers *handlers;
- rcu_read_lock();
- /*
- * Called from the timer, no need to check if handlers is
- * valid.
- */
- list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
- /* No event requests when in maintenance mode. */
- if (intf->maintenance_mode_enable)
- continue;
+ /* No event requests when in maintenance mode. */
+ if (intf->maintenance_mode_enable)
+ return;
- handlers = intf->handlers;
- if (handlers)
- handlers->request_events(intf->send_info);
- }
- rcu_read_unlock();
+ handlers = intf->handlers;
+ if (handlers)
+ handlers->request_events(intf->send_info);
}
static struct timer_list ipmi_timer;
-/* Call every ~1000 ms. */
-#define IPMI_TIMEOUT_TIME 1000
-
-/* How many jiffies does it take to get to the timeout time. */
-#define IPMI_TIMEOUT_JIFFIES ((IPMI_TIMEOUT_TIME * HZ) / 1000)
-
-/*
- * Request events from the queue every second (this is the number of
- * IPMI_TIMEOUT_TIMES between event requests). Hopefully, in the
- * future, IPMI will add a way to know immediately if an event is in
- * the queue and this silliness can go away.
- */
-#define IPMI_REQUEST_EV_TIME (1000 / (IPMI_TIMEOUT_TIME))
-
static atomic_t stop_operation;
-static unsigned int ticks_to_req_ev = IPMI_REQUEST_EV_TIME;
static void ipmi_timeout(unsigned long data)
{
+ ipmi_smi_t intf;
+ int nt = 0;
+
if (atomic_read(&stop_operation))
return;
- ticks_to_req_ev--;
- if (ticks_to_req_ev == 0) {
- ipmi_request_event();
- ticks_to_req_ev = IPMI_REQUEST_EV_TIME;
- }
+ rcu_read_lock();
+ list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
+ int lnt = 0;
+
+ if (atomic_read(&intf->event_waiters)) {
+ intf->ticks_to_req_ev--;
+ if (intf->ticks_to_req_ev == 0) {
+ ipmi_request_event(intf);
+ intf->ticks_to_req_ev = IPMI_REQUEST_EV_TIME;
+ }
+ lnt++;
+ }
- ipmi_timeout_handler(IPMI_TIMEOUT_TIME);
+ lnt += ipmi_timeout_handler(intf, IPMI_TIMEOUT_TIME);
- mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
+ lnt = !!lnt;
+ if (lnt != intf->last_needs_timer &&
+ intf->handlers->set_need_watch)
+ intf->handlers->set_need_watch(intf->send_info, lnt);
+ intf->last_needs_timer = lnt;
+
+ nt += lnt;
+ }
+ rcu_read_unlock();
+
+ if (nt)
+ mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
}
+static void need_waiter(ipmi_smi_t intf)
+{
+ /* Racy, but worst case we start the timer twice. */
+ if (!timer_pending(&ipmi_timer))
+ mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
+}
static atomic_t smi_msg_inuse_count = ATOMIC_INIT(0);
static atomic_t recv_msg_inuse_count = ATOMIC_INIT(0);