[IA64] Fix large MCA bootmem allocation

The MCA code allocates bootmem memory for NR_CPUS, regardless
of how many cpus the system actually has.  This change allocates
memory only for cpus that actually exist.

On my test system with NR_CPUS = 1024, reserved memory was reduced by 130944k.

Before: Memory: 27886976k/28111168k available (8282k code, 242304k reserved, 5928k data, 1792k init)
After:  Memory: 28017920k/28111168k available (8282k code, 111360k reserved, 5928k data, 1792k init)

Signed-off-by: Russ Anderson <rja@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 26 insertions, 29 deletions

diff --git a/arch/ia64/kernel/mca.c b/arch/ia64/kernel/mca.c
index 846e7e036b1..6e17aed5313 100644
--- a/arch/ia64/kernel/mca.c
+++ b/arch/ia64/kernel/mca.c
@@ -17,7 +17,7 @@
  * Copyright (C) 2000 Intel
  * Copyright (C) Chuck Fleckenstein <cfleck@co.intel.com>
  *
- * Copyright (C) 1999, 2004 Silicon Graphics, Inc.
+ * Copyright (C) 1999, 2004-2008 Silicon Graphics, Inc.
  * Copyright (C) Vijay Chander <vijay@engr.sgi.com>
  *
  * Copyright (C) 2006 FUJITSU LIMITED
@@ -1762,11 +1762,8 @@ format_mca_init_stack(void *mca_data, unsigned long offset,
 /* Caller prevents this from being called after init */
 static void * __init_refok mca_bootmem(void)
 {
-        void *p;
-
-        p = alloc_bootmem(sizeof(struct ia64_mca_cpu) * NR_CPUS +
-                          KERNEL_STACK_SIZE);
-        return (void *)ALIGN((unsigned long)p, KERNEL_STACK_SIZE);
+        return __alloc_bootmem(sizeof(struct ia64_mca_cpu),
+                            KERNEL_STACK_SIZE, 0);
 }
 
 /* Do per-CPU MCA-related initialization.  */
@@ -1774,33 +1771,33 @@ void __cpuinit
 ia64_mca_cpu_init(void *cpu_data)
 {
         void *pal_vaddr;
+        void *data;
+        long sz = sizeof(struct ia64_mca_cpu);
+        int cpu = smp_processor_id();
         static int first_time = 1;
 
-        if (first_time) {
-                void *mca_data;
-                int cpu;
-
-                first_time = 0;
-                mca_data = mca_bootmem();
-                for (cpu = 0; cpu < NR_CPUS; cpu++) {
-                        format_mca_init_stack(mca_data,
-                                        offsetof(struct ia64_mca_cpu, mca_stack),
-                                        "MCA", cpu);
-                        format_mca_init_stack(mca_data,
-                                        offsetof(struct ia64_mca_cpu, init_stack),
-                                        "INIT", cpu);
-                        __per_cpu_mca[cpu] = __pa(mca_data);
-                        mca_data += sizeof(struct ia64_mca_cpu);
-                }
-        }
-
         /*
-         * The MCA info structure was allocated earlier and its
-         * physical address saved in __per_cpu_mca[cpu].  Copy that
-         * address * to ia64_mca_data so we can access it as a per-CPU
-         * variable.
+         * Structure will already be allocated if cpu has been online,
+         * then offlined.
          */
-        __get_cpu_var(ia64_mca_data) = __per_cpu_mca[smp_processor_id()];
+        if (__per_cpu_mca[cpu]) {
+                data = __va(__per_cpu_mca[cpu]);
+        } else {
+                if (first_time) {
+                        data = mca_bootmem();
+                        first_time = 0;
+                } else
+                        data = page_address(alloc_pages_node(numa_node_id(),
+                                        GFP_KERNEL, get_order(sz)));
+                if (!data)
+                        panic("Could not allocate MCA memory for cpu %d\n",
+                                        cpu);
+        }
+        format_mca_init_stack(data, offsetof(struct ia64_mca_cpu, mca_stack),
+                "MCA", cpu);
+        format_mca_init_stack(data, offsetof(struct ia64_mca_cpu, init_stack),
+                "INIT", cpu);
+        __get_cpu_var(ia64_mca_data) = __per_cpu_mca[cpu] = __pa(data);
 
         /*
          * Stash away a copy of the PTE needed to map the per-CPU page.