Messages in this thread | | | From | Frederic Weisbecker <> | Subject | [GIT PULL] isolation: 1Hz residual tick offloading v4 | Date | Fri, 19 Jan 2018 01:02:14 +0100 |
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Ingo,
Please pull the sched/0hz-v2 branch that can be found at:
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git sched/0hz-v2
HEAD: 9b14d5204490f9acd03998a5e406ecadb87cddba
Changes in v4:
* Remove the nohz_offload option, just stick with the existing interface, the change is transparent. Suggested by Luiz.
* Automatically pin workqueues to housekeepers.
--- 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 offloads this residual 1Hz tick to workqueues. This way the nohz full CPUs don't have anymore tick (assuming nothing else requires it) as their residual 1Hz tick get handled by the housekeepers.
Nothing special is required for testing, just use the usual kernel parameters, say on CPUs 1-7:
"nohz_full=1-7" or "isolcpus=nohz_offload,domain,1-7"
Thanks, Frederic ---
Frederic Weisbecker (6): sched: Rename init_rq_hrtick to hrtick_rq_init nohz: Allow to check if remote CPU tick is stopped sched/isolation: Isolate workqueues when "nohz_full=" is set sched/isolation: Residual 1Hz scheduler tick offload sched/nohz: Remove the 1 Hz tick code sched/isolation: Tick offload documentation
Documentation/admin-guide/kernel-parameters.txt | 6 +- include/linux/sched/isolation.h | 1 + include/linux/sched/nohz.h | 4 - include/linux/tick.h | 2 + kernel/sched/core.c | 104 +++++++++++++++++------- kernel/sched/idle_task.c | 1 - kernel/sched/isolation.c | 8 +- kernel/sched/sched.h | 13 +-- kernel/time/tick-sched.c | 13 +-- kernel/workqueue.c | 3 +- 10 files changed, 103 insertions(+), 52 deletions(-)
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