diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c index ec4e10fcf1a51b58f690ad329bdc068bc8252c2f..872c4ec79bf4c81e91e95d1ffdb17c0469a23821 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; @@ -73,6 +74,20 @@ 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. */ @@ -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 @@ -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; @@ -966,6 +984,11 @@ 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) { + /* 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; @@ -1021,6 +1044,12 @@ int ipmi_destroy_user(ipmi_user_t user) user->valid = 0; + 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); list_del_rcu(&user->link); @@ -1184,7 +1213,7 @@ 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 +1223,18 @@ 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 +1328,9 @@ 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 +1372,7 @@ 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); @@ -2876,6 +2919,8 @@ 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 +4010,8 @@ 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 +4023,10 @@ 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 +4043,8 @@ 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 +4090,118 @@ 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 = 0; + 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); diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c index 25a1436a429181f0526879c0d184c9418a28a1fe..444ea548dfe3f910da0960dd82a6ffa86643ce48 100644 --- a/drivers/char/ipmi/ipmi_si_intf.c +++ b/drivers/char/ipmi/ipmi_si_intf.c @@ -257,6 +257,9 @@ struct smi_info { /* Used to gracefully stop the timer without race conditions. */ atomic_t stop_operation; + /* Are we waiting for the events, pretimeouts, received msgs? */ + atomic_t need_watch; + /* * The driver will disable interrupts when it gets into a * situation where it cannot handle messages due to lack of @@ -862,6 +865,19 @@ static enum si_sm_result smi_event_handler(struct smi_info *smi_info, return si_sm_result; } +static void check_start_timer_thread(struct smi_info *smi_info) +{ + if (smi_info->si_state == SI_NORMAL && smi_info->curr_msg == NULL) { + smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES); + + if (smi_info->thread) + wake_up_process(smi_info->thread); + + start_next_msg(smi_info); + smi_event_handler(smi_info, 0); + } +} + static void sender(void *send_info, struct ipmi_smi_msg *msg, int priority) @@ -915,15 +931,7 @@ static void sender(void *send_info, else list_add_tail(&msg->link, &smi_info->xmit_msgs); - if (smi_info->si_state == SI_NORMAL && smi_info->curr_msg == NULL) { - smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES); - - if (smi_info->thread) - wake_up_process(smi_info->thread); - - start_next_msg(smi_info); - smi_event_handler(smi_info, 0); - } + check_start_timer_thread(smi_info); spin_unlock_irqrestore(&smi_info->si_lock, flags); } @@ -1023,9 +1031,15 @@ static int ipmi_thread(void *data) ; /* do nothing */ else if (smi_result == SI_SM_CALL_WITH_DELAY && busy_wait) schedule(); - else if (smi_result == SI_SM_IDLE) - schedule_timeout_interruptible(100); - else + else if (smi_result == SI_SM_IDLE) { + if (atomic_read(&smi_info->need_watch)) { + schedule_timeout_interruptible(100); + } else { + /* Wait to be woken up when we are needed. */ + __set_current_state(TASK_INTERRUPTIBLE); + schedule(); + } + } else schedule_timeout_interruptible(1); } return 0; @@ -1061,6 +1075,17 @@ static void request_events(void *send_info) atomic_set(&smi_info->req_events, 1); } +static void set_need_watch(void *send_info, int enable) +{ + struct smi_info *smi_info = send_info; + unsigned long flags; + + atomic_set(&smi_info->need_watch, enable); + spin_lock_irqsave(&smi_info->si_lock, flags); + check_start_timer_thread(smi_info); + spin_unlock_irqrestore(&smi_info->si_lock, flags); +} + static int initialized; static void smi_timeout(unsigned long data) @@ -1212,6 +1237,7 @@ static struct ipmi_smi_handlers handlers = { .get_smi_info = get_smi_info, .sender = sender, .request_events = request_events, + .set_need_watch = set_need_watch, .set_maintenance_mode = set_maintenance_mode, .set_run_to_completion = set_run_to_completion, .poll = poll, @@ -3352,6 +3378,7 @@ static int try_smi_init(struct smi_info *new_smi) new_smi->interrupt_disabled = 1; atomic_set(&new_smi->stop_operation, 0); + atomic_set(&new_smi->need_watch, 0); new_smi->intf_num = smi_num; smi_num++; diff --git a/include/linux/ipmi.h b/include/linux/ipmi.h index 1f9f56e2885131b1320f6ef1a24e29b45f353dda..76d2acbfa7c69ec1a459d695880d158de75f1ca9 100644 --- a/include/linux/ipmi.h +++ b/include/linux/ipmi.h @@ -237,7 +237,7 @@ int ipmi_set_maintenance_mode(ipmi_user_t user, int mode); * The first user that sets this to TRUE will receive all events that * have been queued while no one was waiting for events. */ -int ipmi_set_gets_events(ipmi_user_t user, int val); +int ipmi_set_gets_events(ipmi_user_t user, bool val); /* * Called when a new SMI is registered. This will also be called on diff --git a/include/linux/ipmi_smi.h b/include/linux/ipmi_smi.h index 8ea3fe0b97598428723615c13a042145685adb99..2a7ff302d99058b512efa2ed5beafa4ea8e34f53 100644 --- a/include/linux/ipmi_smi.h +++ b/include/linux/ipmi_smi.h @@ -109,6 +109,13 @@ struct ipmi_smi_handlers { events from the BMC we are attached to. */ void (*request_events)(void *send_info); + /* Called by the upper layer when some user requires that the + interface watch for events, received messages, watchdog + pretimeouts, or not. Used by the SMI to know if it should + watch for these. This may be NULL if the SMI does not + implement it. */ + void (*set_need_watch)(void *send_info, int enable); + /* Called when the interface should go into "run to completion" mode. If this call sets the value to true, the interface should make sure that all messages are flushed