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Commit b0bc225d authored by Andrew Jones's avatar Andrew Jones Committed by Ingo Molnar
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sched/x86: Construct all sibling maps if smt

Commit 316ad248

 ("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: default avatarAndrew Jones <drjones@redhat.com>
Acked-by: default avatarPeter 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: default avatarIngo Molnar <mingo@kernel.org>
parent dcdbe33a
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