[PATCH] x86_64: add support for Intel dual-core detection and displaying

Appended patch adds the support for Intel dual-core detection and displaying
the core related information in /proc/cpuinfo.  

It adds two new fields "core id" and "cpu cores" to x86 /proc/cpuinfo and the
"core id" field for x86_64("cpu cores" field is already present in x86_64).

Number of processor cores in a die is detected using cpuid(4) and this is
documented in IA-32 Intel Architecture Software Developer's Manual (vol 2a)
(http://developer.intel.com/design/pentium4/manuals/index_new.htm#sdm_vol2a)

This patch also adds cpu_core_map similar to cpu_sibling_map.

Slightly hacked by AK.

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

1 files changed, 8 insertions, 0 deletions

diff --git a/arch/i386/kernel/cpu/proc.c b/arch/i386/kernel/cpu/proc.c
index 89a2956ee65..0f1125b15b7 100644
--- a/arch/i386/kernel/cpu/proc.c
+++ b/arch/i386/kernel/cpu/proc.c
@@ -129,6 +129,14 @@ static int show_cpuinfo(struct seq_file *m, void *v)
         seq_printf(m, "\nbogomips\t: %lu.%02lu\n\n",
                      c->loops_per_jiffy/(500000/HZ),
                      (c->loops_per_jiffy/(5000/HZ)) % 100);
+
+#ifdef CONFIG_SMP
+        /* Put new fields at the end to lower the probability of
+           breaking user space parsers. */
+        seq_printf(m, "core id\t\t: %d\n", cpu_core_id[n]);
+        seq_printf(m, "cpu cores\t: %d\n", c->x86_num_cores);
+#endif
+
         return 0;
 }