Merge remote-tracking branch 'lsk/v3.10/topic/gator' into linux-linaro-lsk

[firefly-linux-kernel-4.4.55.git] / drivers / char / ipmi / ipmi_si_intf.c

diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
index af4b23ffc5a659c4d515e706c66fe80b202c056e..40b3f756f904a7304469f8a4d90e89bf1e88ac53 100644 (file)
--- a/drivers/char/ipmi/ipmi_si_intf.c
+++ b/drivers/char/ipmi/ipmi_si_intf.c
@@ -244,6 +244,9 @@ struct smi_info {
        /* The timer for this si. */
        struct timer_list   si_timer;
 
+       /* This flag is set, if the timer is running (timer_pending() isn't enough) */
+       bool                timer_running;
+
        /* The time (in jiffies) the last timeout occurred at. */
        unsigned long       last_timeout_jiffies;
 
@@ -427,6 +430,13 @@ static void start_clear_flags(struct smi_info *smi_info)
        smi_info->si_state = SI_CLEARING_FLAGS;
 }
 
+static void smi_mod_timer(struct smi_info *smi_info, unsigned long new_val)
+{
+       smi_info->last_timeout_jiffies = jiffies;
+       mod_timer(&smi_info->si_timer, new_val);
+       smi_info->timer_running = true;
+}
+
 /*
  * When we have a situtaion where we run out of memory and cannot
  * allocate messages, we just leave them in the BMC and run the system
@@ -439,8 +449,7 @@ static inline void disable_si_irq(struct smi_info *smi_info)
                start_disable_irq(smi_info);
                smi_info->interrupt_disabled = 1;
                if (!atomic_read(&smi_info->stop_operation))
-                       mod_timer(&smi_info->si_timer,
-                                 jiffies + SI_TIMEOUT_JIFFIES);
+                       smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES);
        }
 }
 
@@ -900,15 +909,7 @@ static void sender(void                *send_info,
                list_add_tail(&msg->link, &smi_info->xmit_msgs);
 
        if (smi_info->si_state == SI_NORMAL && smi_info->curr_msg == NULL) {
-               /*
-                * last_timeout_jiffies is updated here to avoid
-                * smi_timeout() handler passing very large time_diff
-                * value to smi_event_handler() that causes
-                * the send command to abort.
-                */
-               smi_info->last_timeout_jiffies = jiffies;
-
-               mod_timer(&smi_info->si_timer, jiffies + SI_TIMEOUT_JIFFIES);
+               smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES);
 
                if (smi_info->thread)
                        wake_up_process(smi_info->thread);
@@ -997,6 +998,17 @@ static int ipmi_thread(void *data)
 
                spin_lock_irqsave(&(smi_info->si_lock), flags);
                smi_result = smi_event_handler(smi_info, 0);
+
+               /*
+                * If the driver is doing something, there is a possible
+                * race with the timer.  If the timer handler see idle,
+                * and the thread here sees something else, the timer
+                * handler won't restart the timer even though it is
+                * required.  So start it here if necessary.
+                */
+               if (smi_result != SI_SM_IDLE && !smi_info->timer_running)
+                       smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES);
+
                spin_unlock_irqrestore(&(smi_info->si_lock), flags);
                busy_wait = ipmi_thread_busy_wait(smi_result, smi_info,
                                                  &busy_until);
@@ -1066,10 +1078,6 @@ static void smi_timeout(unsigned long data)
                     * SI_USEC_PER_JIFFY);
        smi_result = smi_event_handler(smi_info, time_diff);
 
-       spin_unlock_irqrestore(&(smi_info->si_lock), flags);
-
-       smi_info->last_timeout_jiffies = jiffies_now;
-
        if ((smi_info->irq) && (!smi_info->interrupt_disabled)) {
                /* Running with interrupts, only do long timeouts. */
                timeout = jiffies + SI_TIMEOUT_JIFFIES;
@@ -1091,7 +1099,10 @@ static void smi_timeout(unsigned long data)
 
  do_mod_timer:
        if (smi_result != SI_SM_IDLE)
-               mod_timer(&(smi_info->si_timer), timeout);
+               smi_mod_timer(smi_info, timeout);
+       else
+               smi_info->timer_running = false;
+       spin_unlock_irqrestore(&(smi_info->si_lock), flags);
 }
 
 static irqreturn_t si_irq_handler(int irq, void *data)
@@ -1139,8 +1150,7 @@ static int smi_start_processing(void       *send_info,
 
        /* Set up the timer that drives the interface. */
        setup_timer(&new_smi->si_timer, smi_timeout, (long)new_smi);
-       new_smi->last_timeout_jiffies = jiffies;
-       mod_timer(&new_smi->si_timer, jiffies + SI_TIMEOUT_JIFFIES);
+       smi_mod_timer(new_smi, jiffies + SI_TIMEOUT_JIFFIES);
 
        /*
         * Check if the user forcefully enabled the daemon.