mbox series

[0/2] isolation: Exclude dynamically isolated CPUs from housekeeping masks

Message ID 20240229021414.508972-1-longman@redhat.com
Headers
Series isolation: Exclude dynamically isolated CPUs from housekeeping masks |

Message

Waiman Long Feb. 29, 2024, 2:14 a.m. UTC 
  The housekeeping CPU masks, set up by the "isolcpus" and "nohz_full"
boot command line options, are used at boot time to exclude selected
CPUs from running some kernel housekeeping processes to minimize
disturbance to latency sensitive userspace applications. However, some
of housekeeping CPU masks are also checked at run time to avoid using
those isolated CPUs.

The purpose of this patch series is to exclude dynamically isolated
CPUs from some housekeeping masks so that subsystems that check the
housekeeping masks at run time will not see those isolated CPUs. It does
not migrate the housekeeping processes that have been running on those
newly isolated CPUs since bootup to other CPUs. That will hopefully be
done in the near future.

This patch series only updates the HK_TYPE_TIMER and HK_TYPE_RCU
housekeeping masks for the time being, though this is subject to change.

Waiman Long (2):
  sched/isolation: Exclude dynamically isolated CPUs from housekeeping
    masks
  cgroup/cpuset: Exclude isolated CPUs from housekeeping CPU masks

 include/linux/sched/isolation.h |   8 +++
 kernel/cgroup/cpuset.c          |  30 +++++++---
 kernel/sched/isolation.c        | 101 +++++++++++++++++++++++++++++++-
 3 files changed, 131 insertions(+), 8 deletions(-)