[IA64] Count disabled cpus as potential hot-pluggable CPUs

Minor updates to earlier patch.
- Added to documentation to add ia64 as well.
- Minor clarification on how to use disabled cpus
- used plain max instead of max_t per Andew Morton.

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 8 insertions, 11 deletions

diff --git a/arch/ia64/kernel/acpi.c b/arch/ia64/kernel/acpi.c
index 34795ede72e..ecd44bdc839 100644
--- a/arch/ia64/kernel/acpi.c
+++ b/arch/ia64/kernel/acpi.c
@@ -794,24 +794,21 @@ __init void prefill_possible_map(void)
 	int possible, disabled_cpus;
 
 	disabled_cpus = total_cpus - available_cpus;
+
  	if (additional_cpus == -1) {
- 		if (disabled_cpus > 0) {
- 			possible = total_cpus;
+ 		if (disabled_cpus > 0)
 			additional_cpus = disabled_cpus;
-		}
- 		else {
-			possible = available_cpus;
+ 		else
 			additional_cpus = 0;
-		}
- 	} else {
-		possible = available_cpus + additional_cpus;
-	}
+ 	}
+
+	possible = available_cpus + additional_cpus;
+
 	if (possible > NR_CPUS)
 		possible = NR_CPUS;
 
 	printk(KERN_INFO "SMP: Allowing %d CPUs, %d hotplug CPUs\n",
-		possible,
-	        max_t(int, additional_cpus, 0));
+		possible, max((possible - available_cpus), 0));
 
 	for (i = 0; i < possible; i++)
 		cpu_set(i, cpu_possible_map);