[PATCH tip/core/rcu 0/9] Add bitmap (thus CPU) ranges

From: Paul E. McKenney
Date: Wed Mar 03 2021 - 19:17:50 EST


Hello!

This series adds ranges to bitmaps, and thus to CPU numbers, so that a
kernel boot parameter such as "rcu_nocbs=2-N" is now permitted.

1. test_bitmap: clearly separate ERANGE from EINVAL tests, courtesy
of Paul Gortmaker.

2. test_bitmap: add tests to trigger ERANGE case, courtesy of
Paul Gortmaker.

3. test_bitmap: add more start-end:offset/len tests, courtesy of
Paul Gortmaker.

4. bitmap: fold nbits into region struct, courtesy of Paul Gortmaker.

5. bitmap: move ERANGE check from set_region to check_region,
courtesy of Paul Gortmaker.

6. bitmap: support "N" as an alias for size of bitmap, courtesy of
Paul Gortmaker.

7. test_bitmap: add tests for "N" alias, courtesy of Paul Gortmaker.

8. deprecate "all" option to rcu_nocbs=, courtesy of Paul Gortmaker.

9. Use "all" and "N" in "nohz_full" and "rcu_nocbs".

Thanx, Paul

------------------------------------------------------------------------

Documentation/admin-guide/kernel-parameters.rst | 7 +
Documentation/admin-guide/kernel-parameters.txt | 4
kernel/rcu/tree_plugin.h | 6 -
lib/bitmap.c | 55 +++++++------
lib/test_bitmap.c | 46 +++++++++-
tools/testing/selftests/rcutorture/configs/rcu/TREE04.boot | 2
tools/testing/selftests/rcutorture/configs/rcu/TREE08.boot | 2
7 files changed, 84 insertions(+), 38 deletions(-)