On Thu, 15 Feb 2018, Frederic Weisbecker wrote:
> Update the documentation to reflect the 1Hz tick offload changes.
>
> Signed-off-by: Frederic Weisbecker <frede...@kernel.org>
> Cc: Chris Metcalf <cmetc...@mellanox.com>
> Cc: Christoph Lameter <c...@linux.com>
> Cc: Luiz Capitulino <lcapitul...@redhat.com>
> Cc: Mike Galbraith <efa...@gmx.de>
> Cc: Paul E. McKenney <paul...@linux.vnet.ibm.com>
> Cc: Peter Zijlstra <pet...@infradead.org>
> Cc: Rik van Riel <r...@redhat.com>
> Cc: Thomas Gleixner <t...@linutronix.de>
> Cc: Wanpeng Li <kernel...@gmail.com>
> Cc: Ingo Molnar <mi...@kernel.org>
> ---
> Documentation/admin-guide/kernel-parameters.txt | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/Documentation/admin-guide/kernel-parameters.txt
> b/Documentation/admin-guide/kernel-parameters.txt
> index 1d1d53f..50b9837 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -1766,6 +1766,17 @@
>
> nohz
> Disable the tick when a single task runs.
> +
> + A residual 1Hz tick is offloaded to workqueues, which
> you
> + need to affine to housekeeping through the global
> + workqueue's affinity configured via the
> + /sys/devices/virtual/workqueue/cpumask sysfs file, or
> + by using the 'domain' flag described below.
> +
> + NOTE: by default the global workqueue runs on all
> CPUs,
> + so to protect individual CPUs the 'cpumask' file has
> to
> + be configured manually after bootup.
Hmm. Why don't you set that to the housekeeping cpus by default?
Thanks,
tglx
