[PATCH] x86_64: Allow oprofile for model P4 models

Add it for P4 model 6 - reported to work and have a similar PMU to
earlier P4s.

Add an p4force=1 module override parameter for future use.

We had a discussion about that earlier - it's a trade off between the
PMU staying compatible or not.  I think the force parameter is a
reasonable compromise.

Cc: oprofile-list@lists.sf.net
Cc: Asit Mallick <asit.k.mallick@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/i386/oprofile/nmi_int.c

@@ -13,6 +13,7 @@
 #include <linux/oprofile.h>
 #include <linux/sysdev.h>
 #include <linux/slab.h>
+#include <linux/moduleparam.h>
 #include <asm/nmi.h>
 #include <asm/msr.h>
 #include <asm/apic.h>
@@ -296,12 +297,14 @@ static int nmi_create_files(struct super_block * sb, struct dentry * root)
 	return 0;
 }
 
+static int p4force;
+module_param(p4force, int, 0);
 
 static int __init p4_init(char ** cpu_type)
 {
 	__u8 cpu_model = boot_cpu_data.x86_model;
 
-	if (cpu_model > 4)
+	if (!p4force && (cpu_model > 6 || cpu_model == 5))
 		return 0;
 
 #ifndef CONFIG_SMP