x86, ioapic: Use ioapic_saved_data while enabling intr-remapping

Code flow for enabling interrupt-remapping was
allocating/freeing buffers for saving/restoring io-apic RTE's.
ioapic suspend/resume code uses boot time allocated
ioapic_saved_data that is a perfect match for reuse here.

This will remove the unnecessary allocation/free of the
temporary buffers during suspend/resume of interrupt-remapping
enabled platforms aswell as paving the way for further code
consolidation.

Tested-by: Daniel J Blueman <daniel.blueman@gmail.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/20110518233157.574469296@sbsiddha-MOBL3.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 13 insertions, 35 deletions

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index f92a8e5d1e21..b961af86bfea 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1461,7 +1461,6 @@ int __init enable_IR(void)
 void __init enable_IR_x2apic(void)
 {
         unsigned long flags;
-        struct IO_APIC_route_entry **ioapic_entries;
         int ret, x2apic_enabled = 0;
         int dmar_table_init_ret;
 
@@ -1469,13 +1468,7 @@ void __init enable_IR_x2apic(void)
         if (dmar_table_init_ret && !x2apic_supported())
                 return;
 
-        ioapic_entries = alloc_ioapic_entries();
-        if (!ioapic_entries) {
-                pr_err("Allocate ioapic_entries failed\n");
-                goto out;
-        }
-
-        ret = save_IO_APIC_setup(ioapic_entries);
+        ret = save_ioapic_entries();
         if (ret) {
                 pr_info("Saving IO-APIC state failed: %d\n", ret);
                 goto out;
@@ -1483,7 +1476,7 @@ void __init enable_IR_x2apic(void)
 
         local_irq_save(flags);
         legacy_pic->mask_all();
-        mask_IO_APIC_setup(ioapic_entries);
+        mask_ioapic_entries();
 
         if (dmar_table_init_ret)
                 ret = 0;
@@ -1514,14 +1507,11 @@ void __init enable_IR_x2apic(void)
 
 nox2apic:
         if (!ret) /* IR enabling failed */
-                restore_IO_APIC_setup(ioapic_entries);
+                restore_ioapic_entries();
         legacy_pic->restore_mask();
         local_irq_restore(flags);
 
 out:
-        if (ioapic_entries)
-                free_ioapic_entries(ioapic_entries);
-
         if (x2apic_enabled)
                 return;
 
@@ -2095,28 +2085,20 @@ static void lapic_resume(void)
 {
         unsigned int l, h;
         unsigned long flags;
-        int maxlvt, ret;
-        struct IO_APIC_route_entry **ioapic_entries = NULL;
+        int maxlvt;
 
         if (!apic_pm_state.active)
                 return;
 
         local_irq_save(flags);
         if (intr_remapping_enabled) {
-                ioapic_entries = alloc_ioapic_entries();
-                if (!ioapic_entries) {
-                        WARN(1, "Alloc ioapic_entries in lapic resume failed.");
-                        goto restore;
-                }
-
-                ret = save_IO_APIC_setup(ioapic_entries);
-                if (ret) {
-                        WARN(1, "Saving IO-APIC state failed: %d\n", ret);
-                        free_ioapic_entries(ioapic_entries);
-                        goto restore;
-                }
-
-                mask_IO_APIC_setup(ioapic_entries);
+                /*
+                 * IO-APIC and PIC have their own resume routines.
+                 * We just mask them here to make sure the interrupt
+                 * subsystem is completely quiet while we enable x2apic
+                 * and interrupt-remapping.
+                 */
+                mask_ioapic_entries();
                 legacy_pic->mask_all();
         }
 
@@ -2159,13 +2141,9 @@ static void lapic_resume(void)
         apic_write(APIC_ESR, 0);
         apic_read(APIC_ESR);
 
-        if (intr_remapping_enabled) {
+        if (intr_remapping_enabled)
                 reenable_intr_remapping(x2apic_mode);
-                legacy_pic->restore_mask();
-                restore_IO_APIC_setup(ioapic_entries);
-                free_ioapic_entries(ioapic_entries);
-        }
-restore:
+
         local_irq_restore(flags);
 }