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    Subject[PATCH 3.2 02/74] sched/topology: Fix building of overlapping sched-groups
    3.2.94-rc1 review patch.  If anyone has any objections, please let me know.

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

    From: Peter Zijlstra <peterz@infradead.org>

    commit 0372dd2736e02672ac6e189c31f7d8c02ad543cd upstream.

    When building the overlapping groups, we very obviously should start
    with the previous domain of _this_ @cpu, not CPU-0.

    This can be readily demonstrated with a topology like:

    node 0 1 2 3
    0: 10 20 30 20
    1: 20 10 20 30
    2: 30 20 10 20
    3: 20 30 20 10

    Where (for example) CPU1 ends up generating the following nonsensical groups:

    [] CPU1 attaching sched-domain:
    [] domain 0: span 0-2 level NUMA
    [] groups: 1 2 0
    [] domain 1: span 0-3 level NUMA
    [] groups: 1-3 (cpu_capacity = 3072) 0-1,3 (cpu_capacity = 3072)

    Where the fact that domain 1 doesn't include a group with span 0-2 is
    the obvious fail.

    With patch this looks like:

    [] CPU1 attaching sched-domain:
    [] domain 0: span 0-2 level NUMA
    [] groups: 1 0 2
    [] domain 1: span 0-3 level NUMA
    [] groups: 0-2 (cpu_capacity = 3072) 0,2-3 (cpu_capacity = 3072)

    Debugged-by: Lauro Ramos Venancio <lvenanci@redhat.com>
    Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Mike Galbraith <efault@gmx.de>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: linux-kernel@vger.kernel.org
    Fixes: e3589f6c81e4 ("sched: Allow for overlapping sched_domain spans")
    Signed-off-by: Ingo Molnar <mingo@kernel.org>
    [bwh: Backported to 3.2: adjust filename]
    Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
    ---
    kernel/sched.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    --- a/kernel/sched.c
    +++ b/kernel/sched.c
    @@ -7479,7 +7479,7 @@ build_overlap_sched_groups(struct sched_

    cpumask_clear(covered);

    - for_each_cpu(i, span) {
    + for_each_cpu_wrap(i, span, cpu) {
    struct cpumask *sg_span;

    if (cpumask_test_cpu(i, covered))
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