[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>
diff --git a/arch/i386/kernel/smpboot.c b/arch/i386/kernel/smpboot.c
index 332ee7a..fd36d2f 100644
--- a/arch/i386/kernel/smpboot.c
+++ b/arch/i386/kernel/smpboot.c
@@ -62,6 +62,8 @@
int smp_num_siblings = 1;
int phys_proc_id[NR_CPUS]; /* Package ID of each logical CPU */
EXPORT_SYMBOL(phys_proc_id);
+int cpu_core_id[NR_CPUS]; /* Core ID of each logical CPU */
+EXPORT_SYMBOL(cpu_core_id);
/* bitmap of online cpus */
cpumask_t cpu_online_map;
@@ -885,6 +887,7 @@
void *xquad_portio;
cpumask_t cpu_sibling_map[NR_CPUS] __cacheline_aligned;
+cpumask_t cpu_core_map[NR_CPUS] __cacheline_aligned;
static void __init smp_boot_cpus(unsigned int max_cpus)
{
@@ -907,6 +910,9 @@
cpus_clear(cpu_sibling_map[0]);
cpu_set(0, cpu_sibling_map[0]);
+ cpus_clear(cpu_core_map[0]);
+ cpu_set(0, cpu_core_map[0]);
+
/*
* If we couldn't find an SMP configuration at boot time,
* get out of here now!
@@ -919,6 +925,8 @@
printk(KERN_NOTICE "Local APIC not detected."
" Using dummy APIC emulation.\n");
map_cpu_to_logical_apicid();
+ cpu_set(0, cpu_sibling_map[0]);
+ cpu_set(0, cpu_core_map[0]);
return;
}
@@ -942,6 +950,8 @@
printk(KERN_ERR "... forcing use of dummy APIC emulation. (tell your hw vendor)\n");
smpboot_clear_io_apic_irqs();
phys_cpu_present_map = physid_mask_of_physid(0);
+ cpu_set(0, cpu_sibling_map[0]);
+ cpu_set(0, cpu_core_map[0]);
return;
}
@@ -955,6 +965,8 @@
printk(KERN_INFO "SMP mode deactivated, forcing use of dummy APIC emulation.\n");
smpboot_clear_io_apic_irqs();
phys_cpu_present_map = physid_mask_of_physid(0);
+ cpu_set(0, cpu_sibling_map[0]);
+ cpu_set(0, cpu_core_map[0]);
return;
}
@@ -1035,10 +1047,13 @@
* construct cpu_sibling_map[], so that we can tell sibling CPUs
* efficiently.
*/
- for (cpu = 0; cpu < NR_CPUS; cpu++)
+ for (cpu = 0; cpu < NR_CPUS; cpu++) {
cpus_clear(cpu_sibling_map[cpu]);
+ cpus_clear(cpu_core_map[cpu]);
+ }
for (cpu = 0; cpu < NR_CPUS; cpu++) {
+ struct cpuinfo_x86 *c = cpu_data + cpu;
int siblings = 0;
int i;
if (!cpu_isset(cpu, cpu_callout_map))
@@ -1048,7 +1063,7 @@
for (i = 0; i < NR_CPUS; i++) {
if (!cpu_isset(i, cpu_callout_map))
continue;
- if (phys_proc_id[cpu] == phys_proc_id[i]) {
+ if (cpu_core_id[cpu] == cpu_core_id[i]) {
siblings++;
cpu_set(i, cpu_sibling_map[cpu]);
}
@@ -1060,6 +1075,18 @@
if (siblings != smp_num_siblings)
printk(KERN_WARNING "WARNING: %d siblings found for CPU%d, should be %d\n", siblings, cpu, smp_num_siblings);
+
+ if (c->x86_num_cores > 1) {
+ for (i = 0; i < NR_CPUS; i++) {
+ if (!cpu_isset(i, cpu_callout_map))
+ continue;
+ if (phys_proc_id[cpu] == phys_proc_id[i]) {
+ cpu_set(i, cpu_core_map[cpu]);
+ }
+ }
+ } else {
+ cpu_core_map[cpu] = cpu_sibling_map[cpu];
+ }
}
if (nmi_watchdog == NMI_LOCAL_APIC)