[PATCH] x86-64/i386: Intel HT, Multi core detection fixes

Fields obtained through cpuid vector 0x1(ebx[16:23]) and
vector 0x4(eax[14:25], eax[26:31]) indicate the maximum values and might not
always be the same as what is available and what OS sees.  So make sure
"siblings" and "cpu cores" values in /proc/cpuinfo reflect the values as seen
by OS instead of what cpuid instruction says. This will also fix the buggy BIOS
cases (for example where cpuid on a single core cpu says there are "2" siblings,
even when HT is disabled in the BIOS.
http://bugzilla.kernel.org/show_bug.cgi?id=4359)

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index cb3c3ef50f50..38c2fb7ebe09 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -84,6 +84,16 @@ static __inline__ int get_bitmask_order(unsigned int count)
         return order;   /* We could be slightly more clever with -1 here... */
 }
 
+static __inline__ int get_count_order(unsigned int count)
+{
+        int order;
+        
+        order = fls(count) - 1;
+        if (count & (count - 1))
+                order++;
+        return order;
+}
+
 /*
  * hweightN: returns the hamming weight (i.e. the number
  * of bits set) of a N-bit word