x86, ioapic: Get rid of needless check and simplify ioapic_setup_resources()

alloc_bootmem() already panics on allocation failure. There is
no need to check the result.

Also there is a way to unbind global variable from its body and
use it as a parameter which allow us to simplify
ioapic_init_mappings as well -- "for" cycle already uses
nr_ioapics as a conditional variable and there is no need to
check if ioapic_setup_resources was returning NULL again.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20090824175551.493629148@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 11 insertions, 15 deletions

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 2999f3dd588..d836b4d347e 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -4053,7 +4053,7 @@ void __init setup_ioapic_dest(void)
 
 static struct resource *ioapic_resources;
 
-static struct resource * __init ioapic_setup_resources(void)
+static struct resource * __init ioapic_setup_resources(int nr_ioapics)
 {
         unsigned long n;
         struct resource *res;
@@ -4069,15 +4069,13 @@ static struct resource * __init ioapic_setup_resources(void)
         mem = alloc_bootmem(n);
         res = (void *)mem;
 
-        if (mem != NULL) {
-                mem += sizeof(struct resource) * nr_ioapics;
+        mem += sizeof(struct resource) * nr_ioapics;
 
-                for (i = 0; i < nr_ioapics; i++) {
-                        res[i].name = mem;
-                        res[i].flags = IORESOURCE_MEM | IORESOURCE_BUSY;
-                        sprintf(mem,  "IOAPIC %u", i);
-                        mem += IOAPIC_RESOURCE_NAME_SIZE;
-                }
+        for (i = 0; i < nr_ioapics; i++) {
+                res[i].name = mem;
+                res[i].flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+                sprintf(mem,  "IOAPIC %u", i);
+                mem += IOAPIC_RESOURCE_NAME_SIZE;
         }
 
         ioapic_resources = res;
@@ -4091,7 +4089,7 @@ void __init ioapic_init_mappings(void)
         struct resource *ioapic_res;
         int i;
 
-        ioapic_res = ioapic_setup_resources();
+        ioapic_res = ioapic_setup_resources(nr_ioapics);
         for (i = 0; i < nr_ioapics; i++) {
                 if (smp_found_config) {
                         ioapic_phys = mp_ioapics[i].apicaddr;
@@ -4120,11 +4118,9 @@ fake_ioapic_page:
                             __fix_to_virt(idx), ioapic_phys);
                 idx++;
 
-                if (ioapic_res != NULL) {
-                        ioapic_res->start = ioapic_phys;
-                        ioapic_res->end = ioapic_phys + (4 * 1024) - 1;
-                        ioapic_res++;
-                }
+                ioapic_res->start = ioapic_phys;
+                ioapic_res->end = ioapic_phys + (4 * 1024) - 1;
+                ioapic_res++;
         }
 }