From 94605eff572b727aaad9b4b29bc358b919096503 Mon Sep 17 00:00:00 2001 From: "Siddha, Suresh B" Date: Sat, 5 Nov 2005 17:25:54 +0100 Subject: [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 Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- include/linux/bitops.h | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'include/linux/bitops.h') 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 -- cgit v1.2.3-59-g8ed1b