sparc64: Fix irq stack bootmem allocation.

Currently, irq stack bootmem is allocated for all possible cpus
before nr_cpus value changes the list of possible cpus. As a result,
there is unnecessary wastage of bootmemory.

Move the irq stack bootmem allocation so that it happens after
possible cpu list is modified based on nr_cpus value.

Signed-off-by: Atish Patra <atish.patra@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 25 insertions, 16 deletions

diff --git a/arch/sparc/kernel/setup_64.c b/arch/sparc/kernel/setup_64.c
index f32cfe83dfd1..6b7331d198e9 100644
--- a/arch/sparc/kernel/setup_64.c
+++ b/arch/sparc/kernel/setup_64.c
@@ -31,6 +31,7 @@
 #include <linux/initrd.h>
 #include <linux/module.h>
 #include <linux/start_kernel.h>
+#include <linux/bootmem.h>
 
 #include <asm/io.h>
 #include <asm/processor.h>
@@ -50,6 +51,8 @@
 #include <asm/elf.h>
 #include <asm/mdesc.h>
 #include <asm/cacheflush.h>
+#include <asm/dma.h>
+#include <asm/irq.h>
 
 #ifdef CONFIG_IP_PNP
 #include <net/ipconfig.h>
@@ -590,6 +593,22 @@ static void __init init_sparc64_elf_hwcap(void)
                 pause_patch();
 }
 
+void __init alloc_irqstack_bootmem(void)
+{
+        unsigned int i, node;
+
+        for_each_possible_cpu(i) {
+                node = cpu_to_node(i);
+
+                softirq_stack[i] = __alloc_bootmem_node(NODE_DATA(node),
+                                                        THREAD_SIZE,
+                                                        THREAD_SIZE, 0);
+                hardirq_stack[i] = __alloc_bootmem_node(NODE_DATA(node),
+                                                        THREAD_SIZE,
+                                                        THREAD_SIZE, 0);
+        }
+}
+
 void __init setup_arch(char **cmdline_p)
 {
         /* Initialize PROM console and command line. */
@@ -651,6 +670,12 @@ void __init setup_arch(char **cmdline_p)
         paging_init();
         init_sparc64_elf_hwcap();
         smp_fill_in_cpu_possible_map();
+        /*
+         * Once the OF device tree and MDESC have been setup and nr_cpus has
+         * been parsed, we know the list of possible cpus.  Therefore we can
+         * allocate the IRQ stacks.
+         */
+        alloc_irqstack_bootmem();
 }
 
 extern int stop_a_enabled;
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index 80031fc2e2d6..7ac6b62fb7c1 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -2081,7 +2081,6 @@ void __init paging_init(void)
 {
         unsigned long end_pfn, shift, phys_base;
         unsigned long real_end, i;
-        int node;
 
         setup_page_offset();
 
@@ -2250,21 +2249,6 @@ void __init paging_init(void)
         /* Setup bootmem... */
         last_valid_pfn = end_pfn = bootmem_init(phys_base);
 
-        /* Once the OF device tree and MDESC have been setup, we know
-         * the list of possible cpus.  Therefore we can allocate the
-         * IRQ stacks.
-         */
-        for_each_possible_cpu(i) {
-                node = cpu_to_node(i);
-
-                softirq_stack[i] = __alloc_bootmem_node(NODE_DATA(node),
-                                                        THREAD_SIZE,
-                                                        THREAD_SIZE, 0);
-                hardirq_stack[i] = __alloc_bootmem_node(NODE_DATA(node),
-                                                        THREAD_SIZE,
-                                                        THREAD_SIZE, 0);
-        }
-
         kernel_physical_mapping_init();
 
         {