[PATCH] make bigsmp the default mode if CONFIG_HOTPLUG_CPU

If we are using hotplug enabled kernel, then make bigsmp the default mode.

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 18 insertions, 8 deletions

diff --git a/arch/i386/kernel/mpparse.c b/arch/i386/kernel/mpparse.c
index 1ca5269b1e86..91a64016956e 100644
--- a/arch/i386/kernel/mpparse.c
+++ b/arch/i386/kernel/mpparse.c
@@ -38,6 +38,12 @@
 int smp_found_config;
 unsigned int __initdata maxcpus = NR_CPUS;
 
+#ifdef CONFIG_HOTPLUG_CPU
+#define CPU_HOTPLUG_ENABLED     (1)
+#else
+#define CPU_HOTPLUG_ENABLED     (0)
+#endif
+
 /*
  * Various Linux-internal data structures created from the
  * MP-table.
@@ -219,14 +225,18 @@ static void __devinit MP_processor_info (struct mpc_config_processor *m)
         cpu_set(num_processors, cpu_possible_map);
         num_processors++;
 
-        if ((num_processors > 8) &&
-            ((APIC_XAPIC(ver) &&
-             (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)) ||
-             (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)))
-                def_to_bigsmp = 1;
-        else
-                def_to_bigsmp = 0;
-
+        if (CPU_HOTPLUG_ENABLED || (num_processors > 8)) {
+                switch (boot_cpu_data.x86_vendor) {
+                case X86_VENDOR_INTEL:
+                        if (!APIC_XAPIC(ver)) {
+                                def_to_bigsmp = 0;
+                                break;
+                        }
+                        /* If P4 and above fall through */
+                case X86_VENDOR_AMD:
+                        def_to_bigsmp = 1;
+                }
+        }
         bios_cpu_apicid[num_processors - 1] = m->mpc_apicid;
 }