Commit-ID: 08bedae1d0acd8c9baf514fb69fa199d0c8345f6 Gitweb: http://git.kernel.org/tip/08bedae1d0acd8c9baf514fb69fa199d0c8345f6 Author: Peter Zijlstra <pet...@infradead.org> AuthorDate: Thu, 6 Sep 2012 00:03:50 +0200 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Thu, 13 Sep 2012 16:52:05 +0200
sched: Fix load avg vs. cpu-hotplug Commit f319da0c68 ("sched: Fix load avg vs cpu-hotplug") was an incomplete fix: In particular, the problem is that at the point it calls calc_load_migrate() nr_running := 1 (the stopper thread), so move the call to CPU_DEAD where we're sure that nr_running := 0. Also note that we can call calc_load_migrate() without serialization, we know the state of rq is stable since its cpu is dead, and we modify the global state using appropriate atomic ops. Suggested-by: Paul E. McKenney <paul...@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijls...@chello.nl> Link: http://lkml.kernel.org/r/1346882630.2600.59.camel@twins Signed-off-by: Ingo Molnar <mi...@kernel.org> --- kernel/sched/core.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 8b51b2d..ba144b1 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5048,7 +5048,9 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) migrate_tasks(cpu); BUG_ON(rq->nr_running != 1); /* the migration thread */ raw_spin_unlock_irqrestore(&rq->lock, flags); + break; + case CPU_DEAD: calc_load_migrate(rq); break; #endif -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/