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x86/numa: Hard partition cpu topology masks on node boundaries
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When using numa=fake= you can get weird topologies where LLCs can span
nodes and other such nonsense. Cure this by hard partitioning these
masks on node boundaries.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/n/tip-di5vwjm96q5vrb76opwuflwx@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Peter Zijlstra authored and Ingo Molnar committed May 9, 2012
1 parent 94c0dd3 commit 0acbb44
Showing 1 changed file with 11 additions and 0 deletions.
11 changes: 11 additions & 0 deletions arch/x86/kernel/smpboot.c
Original file line number Diff line number Diff line change
Expand Up @@ -337,6 +337,11 @@ void __cpuinit set_cpu_sibling_map(int cpu)
for_each_cpu(i, cpu_sibling_setup_mask) {
struct cpuinfo_x86 *o = &cpu_data(i);

#ifdef CONFIG_NUMA_EMU
if (cpu_to_node(cpu) != cpu_to_node(i))
continue;
#endif

if (cpu_has(c, X86_FEATURE_TOPOEXT)) {
if (c->phys_proc_id == o->phys_proc_id &&
per_cpu(cpu_llc_id, cpu) == per_cpu(cpu_llc_id, i) &&
Expand All @@ -360,11 +365,17 @@ void __cpuinit set_cpu_sibling_map(int cpu)
}

for_each_cpu(i, cpu_sibling_setup_mask) {
#ifdef CONFIG_NUMA_EMU
if (cpu_to_node(cpu) != cpu_to_node(i))
continue;
#endif

if (per_cpu(cpu_llc_id, cpu) != BAD_APICID &&
per_cpu(cpu_llc_id, cpu) == per_cpu(cpu_llc_id, i)) {
cpumask_set_cpu(i, cpu_llc_shared_mask(cpu));
cpumask_set_cpu(cpu, cpu_llc_shared_mask(i));
}

if (c->phys_proc_id == cpu_data(i).phys_proc_id) {
cpumask_set_cpu(i, cpu_core_mask(cpu));
cpumask_set_cpu(cpu, cpu_core_mask(i));
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