From b874b985c816c74a9bda04082f18db88dcbc808a Mon Sep 17 00:00:00 2001 From: Corey Minyard Date: Thu, 6 Nov 2014 17:01:59 -0600 Subject: [PATCH] ipmi: Remove the now unnecessary message queue A message queue was added to the message handler, so the SMI interfaces only need to handle one message at a time. Pull out the message queue. This also leads to some significant simplification in the shutdown of an interface, since the message handler now does a lot of the cleanup. Signed-off-by: Corey Minyard --- drivers/char/ipmi/ipmi_si_intf.c | 112 ++++++++++++--------------------------- 1 file changed, 34 insertions(+), 78 deletions(-) diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c index e36487db0e94..d31a7fce2260 100644 --- a/drivers/char/ipmi/ipmi_si_intf.c +++ b/drivers/char/ipmi/ipmi_si_intf.c @@ -170,8 +170,7 @@ struct smi_info { struct si_sm_handlers *handlers; enum si_type si_type; spinlock_t si_lock; - struct list_head xmit_msgs; - struct list_head hp_xmit_msgs; + struct ipmi_smi_msg *waiting_msg; struct ipmi_smi_msg *curr_msg; enum si_intf_state si_state; @@ -250,9 +249,6 @@ struct smi_info { /* The time (in jiffies) the last timeout occurred at. */ unsigned long last_timeout_jiffies; - /* 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; @@ -355,28 +351,18 @@ static void return_hosed_msg(struct smi_info *smi_info, int cCode) static enum si_sm_result start_next_msg(struct smi_info *smi_info) { int rv; - struct list_head *entry = NULL; #ifdef DEBUG_TIMING struct timeval t; #endif - /* Pick the high priority queue first. */ - if (!list_empty(&(smi_info->hp_xmit_msgs))) { - entry = smi_info->hp_xmit_msgs.next; - } else if (!list_empty(&(smi_info->xmit_msgs))) { - entry = smi_info->xmit_msgs.next; - } - - if (!entry) { + if (!smi_info->waiting_msg) { smi_info->curr_msg = NULL; rv = SI_SM_IDLE; } else { int err; - list_del(entry); - smi_info->curr_msg = list_entry(entry, - struct ipmi_smi_msg, - link); + smi_info->curr_msg = smi_info->waiting_msg; + smi_info->waiting_msg = NULL; #ifdef DEBUG_TIMING do_gettimeofday(&t); printk(KERN_DEBUG "**Start2: %d.%9.9d\n", t.tv_sec, t.tv_usec); @@ -916,14 +902,8 @@ static void sender(void *send_info, struct timeval t; #endif - if (atomic_read(&smi_info->stop_operation)) { - msg->rsp[0] = msg->data[0] | 4; - msg->rsp[1] = msg->data[1]; - msg->rsp[2] = IPMI_ERR_UNSPECIFIED; - msg->rsp_size = 3; - deliver_recv_msg(smi_info, msg); - return; - } + BUG_ON(smi_info->waiting_msg); + smi_info->waiting_msg = msg; #ifdef DEBUG_TIMING do_gettimeofday(&t); @@ -932,16 +912,16 @@ static void sender(void *send_info, if (smi_info->run_to_completion) { /* - * If we are running to completion, then throw it in - * the list and run transactions until everything is - * clear. Priority doesn't matter here. + * If we are running to completion, start it and run + * transactions until everything is clear. */ + smi_info->curr_msg = smi_info->waiting_msg; + smi_info->waiting_msg = NULL; /* * Run to completion means we are single-threaded, no * need for locks. */ - list_add_tail(&(msg->link), &(smi_info->xmit_msgs)); result = smi_event_handler(smi_info, 0); while (result != SI_SM_IDLE) { @@ -953,11 +933,6 @@ static void sender(void *send_info, } spin_lock_irqsave(&smi_info->si_lock, flags); - if (priority > 0) - list_add_tail(&msg->link, &smi_info->hp_xmit_msgs); - else - list_add_tail(&msg->link, &smi_info->xmit_msgs); - check_start_timer_thread(smi_info); spin_unlock_irqrestore(&smi_info->si_lock, flags); } @@ -1095,8 +1070,7 @@ static void request_events(void *send_info) { struct smi_info *smi_info = send_info; - if (atomic_read(&smi_info->stop_operation) || - !smi_info->has_event_buffer) + if (!smi_info->has_event_buffer) return; atomic_set(&smi_info->req_events, 1); @@ -3220,15 +3194,10 @@ static void setup_xaction_handlers(struct smi_info *smi_info) static inline void wait_for_timer_and_thread(struct smi_info *smi_info) { - if (smi_info->intf) { - /* - * The timer and thread are only running if the - * interface has been started up and registered. - */ - if (smi_info->thread != NULL) - kthread_stop(smi_info->thread); + if (smi_info->thread != NULL) + kthread_stop(smi_info->thread); + if (smi_info->timer_running) del_timer_sync(&smi_info->si_timer); - } } static struct ipmi_default_vals @@ -3403,8 +3372,7 @@ static int try_smi_init(struct smi_info *new_smi) setup_oem_data_handler(new_smi); setup_xaction_handlers(new_smi); - INIT_LIST_HEAD(&(new_smi->xmit_msgs)); - INIT_LIST_HEAD(&(new_smi->hp_xmit_msgs)); + new_smi->waiting_msg = NULL; new_smi->curr_msg = NULL; atomic_set(&new_smi->req_events, 0); new_smi->run_to_completion = false; @@ -3412,7 +3380,6 @@ static int try_smi_init(struct smi_info *new_smi) atomic_set(&new_smi->stats[i], 0); new_smi->interrupt_disabled = true; - atomic_set(&new_smi->stop_operation, 0); atomic_set(&new_smi->need_watch, 0); new_smi->intf_num = smi_num; smi_num++; @@ -3497,15 +3464,15 @@ static int try_smi_init(struct smi_info *new_smi) return 0; out_err_stop_timer: - atomic_inc(&new_smi->stop_operation); wait_for_timer_and_thread(new_smi); out_err: new_smi->interrupt_disabled = true; if (new_smi->intf) { - ipmi_unregister_smi(new_smi->intf); + ipmi_smi_t intf = new_smi->intf; new_smi->intf = NULL; + ipmi_unregister_smi(intf); } if (new_smi->irq_cleanup) { @@ -3684,60 +3651,49 @@ module_init(init_ipmi_si); static void cleanup_one_si(struct smi_info *to_clean) { int rv = 0; - unsigned long flags; if (!to_clean) return; + if (to_clean->intf) { + ipmi_smi_t intf = to_clean->intf; + + to_clean->intf = NULL; + rv = ipmi_unregister_smi(intf); + if (rv) { + pr_err(PFX "Unable to unregister device: errno=%d\n", + rv); + } + } + if (to_clean->dev) dev_set_drvdata(to_clean->dev, NULL); list_del(&to_clean->link); - /* Tell the driver that we are shutting down. */ - atomic_inc(&to_clean->stop_operation); - /* - * Make sure the timer and thread are stopped and will not run - * again. + * Make sure that interrupts, the timer and the thread are + * stopped and will not run again. */ + if (to_clean->irq_cleanup) + to_clean->irq_cleanup(to_clean); wait_for_timer_and_thread(to_clean); /* * Timeouts are stopped, now make sure the interrupts are off - * for the device. A little tricky with locks to make sure - * there are no races. + * in the BMC. Note that timers and CPU interrupts are off, + * so no need for locks. */ - spin_lock_irqsave(&to_clean->si_lock, flags); while (to_clean->curr_msg || (to_clean->si_state != SI_NORMAL)) { - spin_unlock_irqrestore(&to_clean->si_lock, flags); poll(to_clean); schedule_timeout_uninterruptible(1); - spin_lock_irqsave(&to_clean->si_lock, flags); } disable_si_irq(to_clean); - spin_unlock_irqrestore(&to_clean->si_lock, flags); - while (to_clean->curr_msg || (to_clean->si_state != SI_NORMAL)) { - poll(to_clean); - schedule_timeout_uninterruptible(1); - } - - /* Clean up interrupts and make sure that everything is done. */ - if (to_clean->irq_cleanup) - to_clean->irq_cleanup(to_clean); while (to_clean->curr_msg || (to_clean->si_state != SI_NORMAL)) { poll(to_clean); schedule_timeout_uninterruptible(1); } - if (to_clean->intf) - rv = ipmi_unregister_smi(to_clean->intf); - - if (rv) { - printk(KERN_ERR PFX "Unable to unregister device: errno=%d\n", - rv); - } - if (to_clean->handlers) to_clean->handlers->cleanup(to_clean->si_sm); -- 2.11.0