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sched/x86: Construct all sibling maps if smt

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Commit 316ad24830 ("sched/x86: Rewrite
set_cpu_sibling_map()") broke the construction of sibling maps,
which also broke the booted_cores accounting.

Before the rewrite, if smt was present, then each map was
updated for each smt sibling. After the rewrite only
cpu_sibling_mask gets updated, as the llc and core maps depend
on 'has_mc = x86_max_cores > 1' instead. This leads to problems
with topologies like the following

(qemu -smp sockets=2,cores=1,threads=2)

  processor       : 0
  physical id     : 0
  siblings        : 1    <= should be 2
  core id         : 0
  cpu cores       : 1

  processor       : 1
  physical id     : 0
  siblings        : 1    <= should be 2
  core id         : 0
  cpu cores       : 0    <= should be 1

  processor       : 2
  physical id     : 1
  siblings        : 1    <= should be 2
  core id         : 0
  cpu cores       : 1

  processor       : 3
  physical id     : 1
  siblings        : 1    <= should be 2
  core id         : 0
  cpu cores       : 0    <= should be 1

This patch restores the former construction by defining has_mc
as (has_smt || x86_max_cores > 1). This should be fine as there
were no (has_smt && !has_mc) conditions in the context.

Aso rename has_mc to has_mp now that it's not just for cores.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: a.p.zijlstra@chello.nl
Cc: fenghua.yu@intel.com
Link: http://lkml.kernel.org/r/1369831695-11970-1-git-send-email-drjones@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Andrew Jones 2013-05-29 14:48:15 +02:00 committed by Ingo Molnar
parent dcdbe33add
commit b0bc225d0e
1 changed files with 4 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
arch/x86/kernel/smpboot.c
View File

@ -372,15 +372,15 @@ static bool __cpuinit match_mc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
void __cpuinit set_cpu_sibling_map(int cpu)
{
bool has_mc = boot_cpu_data.x86_max_cores > 1;
bool has_smt = smp_num_siblings > 1;
bool has_mp = has_smt || boot_cpu_data.x86_max_cores > 1;
struct cpuinfo_x86 *c = &cpu_data(cpu);
struct cpuinfo_x86 *o;
int i;
cpumask_set_cpu(cpu, cpu_sibling_setup_mask);
if (!has_smt && !has_mc) {
if (!has_mp) {
cpumask_set_cpu(cpu, cpu_sibling_mask(cpu));
cpumask_set_cpu(cpu, cpu_llc_shared_mask(cpu));
cpumask_set_cpu(cpu, cpu_core_mask(cpu));
@ -394,7 +394,7 @@ void __cpuinit set_cpu_sibling_map(int cpu)
if ((i == cpu) || (has_smt && match_smt(c, o)))
link_mask(sibling, cpu, i);
if ((i == cpu) || (has_mc && match_llc(c, o)))
if ((i == cpu) || (has_mp && match_llc(c, o)))
link_mask(llc_shared, cpu, i);
}
@ -406,7 +406,7 @@ void __cpuinit set_cpu_sibling_map(int cpu)
for_each_cpu(i, cpu_sibling_setup_mask) {
o = &cpu_data(i);
if ((i == cpu) || (has_mc && match_mc(c, o))) {
if ((i == cpu) || (has_mp && match_mc(c, o))) {
link_mask(core, cpu, i);
/*