[PATCH v3 0/2] sched: Queue task on wakelist in the same llc if the wakee cpu is idle

[Tianchen Ding]

Wakelist can help avoid cache bouncing and offload the overhead of waker
cpu. So far, using wakelist within the same llc only happens on
WF_ON_CPU, and this limitation could be removed to further improve
wakeup performance. The result of Unixbench Pipe-based Context Switching
can be improved up to ~10%.

v3:
Add a patch to fix the check of nr_running.
After that, we can remove WF_ON_CPU to achieve the same purpose.
Thank Valentin and Mel.

v2: https://lore.kernel.org/all/20220527090544.527411-1-dtcccc@xxxxxxxxxxxxxxxxx/
Modify commit log to describe key point in detail.
Add more benchmark results on more archs.

v1: https://lore.kernel.org/all/20220513062427.2375743-1-dtcccc@xxxxxxxxxxxxxxxxx/

Tianchen Ding (2):
  sched: Fix the check of nr_running at queue wakelist
  sched: Remove the limitation of WF_ON_CPU on wakelist if wakee cpu is
    idle

 kernel/sched/core.c  | 27 ++++++++++++++++-----------
 kernel/sched/sched.h |  1 -
 2 files changed, 16 insertions(+), 12 deletions(-)

-- 
2.27.0