[IA64] Cleanup lock order in iosapic_register_intr

Cleanup order of irq_desc.lock and iosapic_lock in
iosapic_register_intr() and iosapic_unregister_intr().

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

diff --git a/arch/ia64/kernel/iosapic.c b/arch/ia64/kernel/iosapic.c
index 29ec86c241941da05fcb497a3ac79afd0fb385b5..b3dcdb7e7fc731ee048d9e764c6e28b0a66c3abf 100644 (file)
--- a/arch/ia64/kernel/iosapic.c
+++ b/arch/ia64/kernel/iosapic.c
@@ -505,7 +505,7 @@ iosapic_version (char __iomem *addr)
 static int iosapic_find_sharable_vector (unsigned long trigger,
                                         unsigned long pol)
 {
-       int i, vector = -1, min_count = -1;
+       int i, vector = -ENOSPC, min_count = -1;
        struct iosapic_intr_info *info;
 
        /*
@@ -513,7 +513,7 @@ static int iosapic_find_sharable_vector (unsigned long trigger,
         * supported yet
         */
        if (trigger == IOSAPIC_EDGE)
-               return -1;
+               return -EINVAL;
 
        for (i = IA64_FIRST_DEVICE_VECTOR; i <= IA64_LAST_DEVICE_VECTOR; i++) {
                info = &iosapic_intr_info[i];
@@ -762,7 +762,7 @@ iosapic_register_intr (unsigned int gsi,
        unsigned long flags;
        struct iosapic_rte_info *rte;
        u32 low32;
-again:
+
        /*
         * If this GSI has already been registered (i.e., it's a
         * shared interrupt, or we lost a race to register it),
@@ -773,36 +773,24 @@ again:
        if (vector > 0) {
                rte = gsi_vector_to_rte(gsi, vector);
                rte->refcnt++;
-               spin_unlock_irqrestore(&iosapic_lock, flags);
-               return vector;
+               goto unlock_iosapic_lock;
        }
-       spin_unlock_irqrestore(&iosapic_lock, flags);
 
        /* If vector is running out, we try to find a sharable vector */
        vector = assign_irq_vector(AUTO_ASSIGN);
        if (vector < 0) {
                vector = iosapic_find_sharable_vector(trigger, polarity);
                if (vector < 0)
-                       return -ENOSPC;
-       }
-
-       spin_lock_irqsave(&irq_desc[vector].lock, flags);
-       spin_lock(&iosapic_lock);
-       if (gsi_to_vector(gsi) > 0) {
-               if (list_empty(&iosapic_intr_info[vector].rtes))
-                       free_irq_vector(vector);
-               spin_unlock(&iosapic_lock);
-               spin_unlock_irqrestore(&irq_desc[vector].lock, flags);
-               goto again;
+                       goto unlock_iosapic_lock;
        }
 
+       spin_lock(&irq_desc[vector].lock);
        dest = get_target_cpu(gsi, vector);
        err = register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY,
                            polarity, trigger);
        if (err < 0) {
-               spin_unlock(&iosapic_lock);
-               spin_unlock_irqrestore(&irq_desc[vector].lock, flags);
-               return err;
+               vector = err;
+               goto unlock_all;
        }
 
        /*
@@ -813,14 +801,15 @@ again:
        if (vector_is_shared(vector) && !(low32 & IOSAPIC_MASK))
                mask = 0;
        set_rte(gsi, vector, dest, mask);
-       spin_unlock(&iosapic_lock);
-       spin_unlock_irqrestore(&irq_desc[vector].lock, flags);
 
        printk(KERN_INFO "GSI %u (%s, %s) -> CPU %d (0x%04x) vector %d\n",
               gsi, (trigger == IOSAPIC_EDGE ? "edge" : "level"),
               (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
               cpu_logical_id(dest), dest, vector);
-
+ unlock_all:
+       spin_unlock(&irq_desc[vector].lock);
+ unlock_iosapic_lock:
+       spin_unlock_irqrestore(&iosapic_lock, flags);
        return vector;
 }
 
@@ -849,9 +838,7 @@ iosapic_unregister_intr (unsigned int gsi)
        }
        vector = irq_to_vector(irq);
 
-       idesc = irq_desc + irq;
-       spin_lock_irqsave(&idesc->lock, flags);
-       spin_lock(&iosapic_lock);
+       spin_lock_irqsave(&iosapic_lock, flags);
        if ((rte = gsi_vector_to_rte(gsi, vector)) == NULL) {
                printk(KERN_ERR "iosapic_unregister_intr(%u) unbalanced\n",
                       gsi);
@@ -862,13 +849,17 @@ iosapic_unregister_intr (unsigned int gsi)
        if (--rte->refcnt > 0)
                goto out;
 
+       /* Remove the rte entry from the list */
+       idesc = irq_desc + irq;
+       spin_lock(&idesc->lock);
+       list_del(&rte->rte_list);
+       spin_unlock(&idesc->lock);
+
        /* Mask the interrupt */
        low32 = iosapic_intr_info[vector].low32 | IOSAPIC_MASK;
        iosapic_write(rte->iosapic->addr,
                      IOSAPIC_RTE_LOW(rte->rte_index), low32);
 
-       /* Remove the rte entry from the list */
-       list_del(&rte->rte_list);
        iosapic_intr_info[vector].count--;
        iosapic_free_rte(rte);
        index = find_iosapic(gsi);
@@ -913,8 +904,7 @@ iosapic_unregister_intr (unsigned int gsi)
                free_irq_vector(vector);
        }
  out:
-       spin_unlock(&iosapic_lock);
-       spin_unlock_irqrestore(&idesc->lock, flags);
+       spin_unlock_irqrestore(&iosapic_lock, flags);
 }
 
 /*