On Mon, Mar 16, 2015 at 10:12:12AM -0700, Kevin Hilman wrote: > Lai Jiangshan <la...@cn.fujitsu.com> writes: > > > On 03/14/2015 07:49 AM, Kevin Hilman wrote: > >> Lai Jiangshan <la...@cn.fujitsu.com> writes: > >> > >>> From: Frederic Weisbecker <fweis...@gmail.com> > >>> > >>> Create a cpumask that limit the affinity of all unbound workqueues. > >>> This cpumask is controlled though a file at the root of the workqueue > >>> sysfs directory. > >>> > >>> It works on a lower-level than the per WQ_SYSFS workqueues cpumask files > >>> such that the effective cpumask applied for a given unbound workqueue is > >>> the intersection of /sys/devices/virtual/workqueue/$WORKQUEUE/cpumask and > >>> the new /sys/devices/virtual/workqueue/cpumask_unbounds file. > >>> > >>> This patch implements the basic infrastructure and the read interface. > >>> cpumask_unbounds is initially set to cpu_possible_mask. > >>> > >>> Cc: Christoph Lameter <c...@linux.com> > >>> Cc: Kevin Hilman <khil...@linaro.org> > >>> Cc: Lai Jiangshan <la...@cn.fujitsu.com> > >>> Cc: Mike Galbraith <bitbuc...@online.de> > >>> Cc: Paul E. McKenney <paul...@linux.vnet.ibm.com> > >>> Cc: Tejun Heo <t...@kernel.org> > >>> Cc: Viresh Kumar <viresh.ku...@linaro.org> > >>> Signed-off-by: Frederic Weisbecker <fweis...@gmail.com> > >>> Signed-off-by: Lai Jiangshan <la...@cn.fujitsu.com> > >> > >> [...] > >> > >>> @@ -5094,6 +5116,9 @@ static int __init init_workqueues(void) > >>> > >>> WARN_ON(__alignof__(struct pool_workqueue) < __alignof__(long long)); > >>> > >>> + BUG_ON(!alloc_cpumask_var(&wq_unbound_cpumask, GFP_KERNEL)); > >>> + cpumask_copy(wq_unbound_cpumask, cpu_possible_mask); > >>> + > >> > >> As I mentioned in an earlier discussion[1], I still think this could > >> default too the housekeeping CPUs in the NO_HZ_FULL case: > >> > >> #ifdef CONFIG_NO_HZ_FULL > >> cpumask_complement(wq_unbound_cpumask, tick_nohz_full_mask); > > > > > > No, the default/booted wq_unbound_cpumask should be cpu_possible_mask. > > > > Even for NO_HZ_FULL? > > IMO, for NO_HZ_FULL, we want the unbound workqueues to be on the > housekeeping CPU(s).
If it should be the default on NO_HZ_FULL, maybe we should do this from the tick nohz code. Some late or fs initcall that will do the workqueue affinity, timer affinity, etc... -- 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/
