From: Chris Metcalf <[email protected]> nohz_full is only useful with isolcpus also set, since otherwise the scheduler has to run periodically to try to determine whether to steal work from other cores.
Accordingly, when booting with nohz_full=xxx on the command line, we should act as if isolcpus=xxx was also set, and set (or extend) the isolcpus set to include the nohz_full cpus. Acked-by: Mike Galbraith <[email protected]> ["thumbs up!"] Acked-by: Rik van Riel <[email protected]> Acked-by: Peter Zijlstra (Intel) <[email protected]> Signed-off-by: Chris Metcalf <[email protected]> Cc: Peter Zijlstra (Intel) <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Rafael J. Wysocki <[email protected]> Cc: Martin Schwidefsky <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Rik van Riel <[email protected]> Signed-off-by: Frederic Weisbecker <[email protected]> --- kernel/sched/core.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 6f149f8..e95b4d8 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -7042,6 +7042,9 @@ void __init sched_init_smp(void) alloc_cpumask_var(&non_isolated_cpus, GFP_KERNEL); alloc_cpumask_var(&fallback_doms, GFP_KERNEL); + /* nohz_full won't take effect without isolating the cpus. */ + tick_nohz_full_add_cpus_to(cpu_isolated_map); + sched_init_numa(); /* -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
