[PATCH v4 2/9] x86/passthrough: Wrap pt_irq_create_bind() restart block in braces

[Julian Vetter <julian.vetter@xxxxxxxxxx>]

Enclose the restart/retry block in pt_irq_create_bind() in an explicit
compound statement to prepare for its extraction into a helper function.
No functional change.

Signed-off-by: Julian Vetter <julian.vetter@xxxxxxxxxx>
---
Changes in v4:
- New patch
- Split out as a preparatory no-functional-change step to make the diff
  in patch 5 (pt_irq_bind_msi() interface change) easier to review
---
 xen/drivers/passthrough/x86/hvm.c | 80 ++++++++++++++++---------------
 1 file changed, 41 insertions(+), 39 deletions(-)

diff --git a/xen/drivers/passthrough/x86/hvm.c 
b/xen/drivers/passthrough/x86/hvm.c
index b73bb55055..691fa1b2c7 100644
--- a/xen/drivers/passthrough/x86/hvm.c
+++ b/xen/drivers/passthrough/x86/hvm.c
@@ -229,52 +229,54 @@ int pt_irq_create_bind(
         return -EINVAL;
 
  restart:
-    write_lock(&d->event_lock);
-
-    hvm_irq_dpci = domain_get_irq_dpci(d);
-    if ( !hvm_irq_dpci && !is_hardware_domain(d) )
     {
-        unsigned int i;
+        write_lock(&d->event_lock);
 
-        /*
-         * NB: the hardware domain doesn't use a hvm_irq_dpci struct because
-         * it's only allowed to identity map GSIs, and so the data contained in
-         * that struct (used to map guest GSIs into machine GSIs and perform
-         * interrupt routing) is completely useless to it.
-         */
-        hvm_irq_dpci = xzalloc(struct hvm_irq_dpci);
-        if ( hvm_irq_dpci == NULL )
+        hvm_irq_dpci = domain_get_irq_dpci(d);
+        if ( !hvm_irq_dpci && !is_hardware_domain(d) )
+        {
+            unsigned int i;
+
+            /*
+             * NB: the hardware domain doesn't use a hvm_irq_dpci struct 
because
+             * it's only allowed to identity map GSIs, and so the data 
contained in
+             * that struct (used to map guest GSIs into machine GSIs and 
perform
+             * interrupt routing) is completely useless to it.
+             */
+            hvm_irq_dpci = xzalloc(struct hvm_irq_dpci);
+            if ( hvm_irq_dpci == NULL )
+            {
+                write_unlock(&d->event_lock);
+                return -ENOMEM;
+            }
+            for ( i = 0; i < NR_HVM_DOMU_IRQS; i++ )
+                INIT_LIST_HEAD(&hvm_irq_dpci->girq[i]);
+
+            hvm_domain_irq(d)->dpci = hvm_irq_dpci;
+        }
+
+        info = pirq_get_info(d, pirq);
+        if ( !info )
         {
             write_unlock(&d->event_lock);
             return -ENOMEM;
         }
-        for ( i = 0; i < NR_HVM_DOMU_IRQS; i++ )
-            INIT_LIST_HEAD(&hvm_irq_dpci->girq[i]);
-
-        hvm_domain_irq(d)->dpci = hvm_irq_dpci;
-    }
-
-    info = pirq_get_info(d, pirq);
-    if ( !info )
-    {
-        write_unlock(&d->event_lock);
-        return -ENOMEM;
-    }
-    pirq_dpci = pirq_dpci(info);
+        pirq_dpci = pirq_dpci(info);
 
-    /*
-     * A crude 'while' loop with us dropping the spinlock and giving
-     * the softirq_dpci a chance to run.
-     * We MUST check for this condition as the softirq could be scheduled
-     * and hasn't run yet. Note that this code replaced tasklet_kill which
-     * would have spun forever and would do the same thing (wait to flush out
-     * outstanding hvm_dirq_assist calls.
-     */
-    if ( pt_pirq_softirq_active(pirq_dpci) )
-    {
-        write_unlock(&d->event_lock);
-        cpu_relax();
-        goto restart;
+        /*
+         * A crude 'while' loop with us dropping the spinlock and giving
+         * the softirq_dpci a chance to run.
+         * We MUST check for this condition as the softirq could be scheduled
+         * and hasn't run yet. Note that this code replaced tasklet_kill which
+         * would have spun forever and would do the same thing (wait to flush 
out
+         * outstanding hvm_dirq_assist calls.
+         */
+        if ( pt_pirq_softirq_active(pirq_dpci) )
+        {
+            write_unlock(&d->event_lock);
+            cpu_relax();
+            goto restart;
+        }
     }
 
     switch ( pt_irq_bind->irq_type )
-- 
2.53.0



--
Julian Vetter | Vates Hypervisor & Kernel Developer

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web: https://vates.tech