On Thu, 4 Jan 2018 05:25:32 +0100 Frederic Weisbecker <frede...@kernel.org> wrote:
> Ingo, > > Please pull the sched/0hz branch that can be found at: > > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git > sched/0hz > > HEAD: 9e932b2cc707209febd130978a5eb9f4a943a3f4 > > -- > Now that scheduler_tick() has become resilient towards the absence of > ticks, current->sched_class->task_tick() is the last piece that needs > at least 1Hz tick to keep scheduler stats alive. > > This patchset adds a flag to the isolcpus boot option to offload the > residual 1Hz tick. This way the nohz_full CPUs don't have anymore tick > (assuming nothing else requires it) as their residual 1Hz tick is > offloaded to the housekeepers. > > For quick testing, say on CPUs 1-7: > > "isolcpus=nohz_offload,domain,1-7" Sorry for being very late to this series, but I've a few comments to make (one right now and others in individual patches). Why are extending isolcpus= given that it's a deprecated interface? Some people have already moved away from isolcpus= now, but with this new feature they will be forced back to using it. What about just adding the new functionality to nohz_full=? That is, no new options, just make the tick go away since this has always been what nohz_full= was intended to do? > > Thanks, > Frederic > --- > > Frederic Weisbecker (5): > sched: Rename init_rq_hrtick to hrtick_rq_init > sched/isolation: Add scheduler tick offloading interface > nohz: Allow to check if remote CPU tick is stopped > sched/isolation: Residual 1Hz scheduler tick offload > sched/isolation: Document "nohz_offload" flag > > > Documentation/admin-guide/kernel-parameters.txt | 7 +- > include/linux/sched/isolation.h | 3 +- > include/linux/tick.h | 2 + > kernel/sched/core.c | 94 > +++++++++++++++++++++++-- > kernel/sched/isolation.c | 10 +++ > kernel/sched/sched.h | 2 + > kernel/time/tick-sched.c | 7 ++ > 7 files changed, 117 insertions(+), 8 deletions(-) >
