x2APIC: simplify resume

There's no need to save and restore the IO-APIC entries, the entries
prior to suspension have already been saved by ioapic_suspend, and
will be restored by ioapic_resume. Note that at the point where
resume_x2apic gets called the IO-APIC has not yet resumed, and hence
all entries should be masked.

Note this shouldn't introduce any functional change.

Suggested-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>

diff --git a/xen/arch/x86/apic.c b/xen/arch/x86/apic.c
index 6cdb50cf41c9c0af006150d38cbfde1d49c4623f..0607eb92a89b3c206754e7921bfbf58a75daf80b 100644 (file)
--- a/xen/arch/x86/apic.c
+++ b/xen/arch/x86/apic.c
@@ -492,35 +492,8 @@ static void __enable_x2apic(void)
 
 static void resume_x2apic(void)
 {
-    struct IO_APIC_route_entry **ioapic_entries = NULL;
-
-    ASSERT(x2apic_enabled);
-
-    ioapic_entries = alloc_ioapic_entries();
-    if ( !ioapic_entries )
-    {
-        printk("Allocate ioapic_entries failed\n");
-        goto out;
-    }
-
-    if ( save_IO_APIC_setup(ioapic_entries) )
-    {
-        printk("Saving IO-APIC state failed\n");
-        goto out;
-    }
-
-    mask_8259A();
-    mask_IO_APIC_setup(ioapic_entries);
-
     iommu_enable_x2apic();
     __enable_x2apic();
-
-    restore_IO_APIC_setup(ioapic_entries);
-    unmask_8259A();
-
-out:
-    if ( ioapic_entries )
-        free_ioapic_entries(ioapic_entries);
 }
 
 void setup_local_APIC(void)