[PATCH 3.19 103/123] x86/apic/numachip: Fix sibling map with NumaChip

From: Greg Kroah-Hartman
Date: Tue Mar 24 2015 - 13:08:36 EST


3.19-stable review patch. If anyone has any objections, please let me know.

------------------

From: Daniel J Blueman <daniel@xxxxxxxxxxxxx>

commit c8a470cab030bae8f9e6e5cfff72b047b7c627a7 upstream.

On NumaChip systems, the physical processor ID assignment wasn't
accounting for the number of nodes in AMD multi-module
processors, giving an incorrect sibling map:

$ cd /sys/devices/system/cpu/cpu29/topology
$ grep . *
core_id:5
core_siblings:00000000,ff000000
core_siblings_list:24-31
physical_package_id:3
thread_siblings:00000000,30000000
thread_siblings_list:28-29

This fixes it:

$ cd /sys/devices/system/cpu/cpu29/topology
$ grep . *
core_id:5
core_siblings:00000000,ffff0000
core_siblings_list:16-31
physical_package_id:1
thread_siblings:00000000,30000000
thread_siblings_list:28-29

Signed-off-by: Daniel J Blueman <daniel@xxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Steffen Persvold <sp@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/1426135950-10110-1-git-send-email-daniel@xxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/x86/kernel/apic/apic_numachip.c | 22 ++++++++++++++++------
1 file changed, 16 insertions(+), 6 deletions(-)

--- a/arch/x86/kernel/apic/apic_numachip.c
+++ b/arch/x86/kernel/apic/apic_numachip.c
@@ -37,10 +37,12 @@ static const struct apic apic_numachip;
static unsigned int get_apic_id(unsigned long x)
{
unsigned long value;
- unsigned int id;
+ unsigned int id = (x >> 24) & 0xff;

- rdmsrl(MSR_FAM10H_NODE_ID, value);
- id = ((x >> 24) & 0xffU) | ((value << 2) & 0xff00U);
+ if (static_cpu_has_safe(X86_FEATURE_NODEID_MSR)) {
+ rdmsrl(MSR_FAM10H_NODE_ID, value);
+ id |= (value << 2) & 0xff00;
+ }

return id;
}
@@ -155,10 +157,18 @@ static int __init numachip_probe(void)

static void fixup_cpu_id(struct cpuinfo_x86 *c, int node)
{
- if (c->phys_proc_id != node) {
- c->phys_proc_id = node;
- per_cpu(cpu_llc_id, smp_processor_id()) = node;
+ u64 val;
+ u32 nodes = 1;
+
+ this_cpu_write(cpu_llc_id, node);
+
+ /* Account for nodes per socket in multi-core-module processors */
+ if (static_cpu_has_safe(X86_FEATURE_NODEID_MSR)) {
+ rdmsrl(MSR_FAM10H_NODE_ID, val);
+ nodes = ((val >> 3) & 7) + 1;
}
+
+ c->phys_proc_id = node / nodes;
}

static int __init numachip_system_init(void)


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