[PATCH v6 0/3] x86/resctrl: Implement rename to help move containers' tasks

[Peter Newman]

Hi Reinette, Fenghua,

This patch series implements the solution Reinette suggested in the
earlier RFD thread[1] for the problem of moving a container's tasks to a
different control group on systems that don't provide enough CLOSIDs to
give every container its own control group.

This patch series assumes that a MON group's CLOSID can simply be
changed to that of a new parent CTRL_MON group. This is allowed on Intel
and AMD, but not MPAM implementations. While we (Google) only foresee
needing this functionality on Intel and AMD systems, this series should
hopefully be a good starting point for supporting MPAM.

Thanks!
-Peter

Updates:

v6:
 - rebase to v6.3-rc7
 - clarify changelog wording
 - clarify error message for non-directory move
 - remove unneeded parenthesis for checkpatch.pl --strict
 - add Reviewed-By's from Reinette

v5:
 - rebase to v6.3-rc4
 - dropped rdt_move_group_tasks() task filter patch
 - code/comment clarifications and errno updates requested by Reinette
 - added Documentation patch

v4:
 - rebase to v6.2
 - commit message updates suggested by Reinette
 - replace rdt_move_one_task() patch with rdt_move_group_tasks() filter
   function patch
 - prevent rename on files or renaming to "mon_groups"
 - optimize simple rename case
 - disallow renaming groups with non-empty cpumask
 - ensure source is a proper MON group directory
 - fix missing rdtgrp->closid update
 - add more last_command_status output

v3: use revised task CLOSID/RMID update IPI sync method from [3]
v2: reworded change logs based on what I've learned from review comments
    in another patch series[2]

[v1] https://lore.kernel.org/lkml/20221115154515.952783-1-peternewman@xxxxxxxxxx/
[v2] https://lore.kernel.org/lkml/20221129120149.1035444-1-peternewman@xxxxxxxxxx/
[v3] https://lore.kernel.org/lkml/20230125101334.1069060-1-peternewman@xxxxxxxxxx/
[v4] https://lore.kernel.org/lkml/20230308131452.383914-1-peternewman@xxxxxxxxxx/
[v5] https://lore.kernel.org/lkml/20230330135558.1019658-1-peternewman@xxxxxxxxxx/

[1] https://lore.kernel.org/lkml/7b09fb62-e61a-65b9-a71e-ab725f527ded@xxxxxxxxx/
[2] https://lore.kernel.org/lkml/54e50a9b-268f-2020-f54c-d38312489e2f@xxxxxxxxx/
[3] https://lore.kernel.org/lkml/20221220161123.432120-1-peternewman@xxxxxxxxxx/

Peter Newman (3):
  x86/resctrl: Factor rdtgroup lock for multi-file ops
  x86/resctrl: Implement rename op for mon groups
  Documentation/x86: Documentation for MON group move feature

 Documentation/x86/resctrl.rst          |   7 ++
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 163 +++++++++++++++++++++++--
 2 files changed, 157 insertions(+), 13 deletions(-)


base-commit: 6a8f57ae2eb07ab39a6f0ccad60c760743051026
-- 
2.40.0.634.g4ca3ef3211-goog