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authorSiddha, Suresh B <suresh.b.siddha@intel.com>2005-11-05 17:25:54 +0100
committerLinus Torvalds <torvalds@g5.osdl.org>2005-11-14 19:55:16 -0800
commit94605eff572b727aaad9b4b29bc358b919096503 (patch)
tree657a848d8ef34d2f94bbad3aa4e5458d2d3f2d2b /include/linux/bitops.h
parente90f22edf432512219cc2952f5811961abbd164f (diff)
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[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>
Diffstat (limited to 'include/linux/bitops.h')
-rw-r--r--include/linux/bitops.h10
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