[GIT PULL] RCU changes for v6.14

["Uladzislau Rezki (Sony)" <urezki@gmail.com>]

Hi Linus,

Please pull the latest RCU git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux.git tags/rcu.release.v6.14

# HEAD: 4b5c2205526cc1579b840893b98eb7545220f7cf:

Merge branches 'fixes.2024.12.14a', 'rcutorture.2024.12.14a', 'srcu.2024.12.14a' and 'torture-test.2024.12.14a' into rcu-merge.2024.12.14a

fixes.2024.12.14a: RCU fixes
rcutorture.2024.12.14a: Torture-test updates
srcu.2024.12.14a: SRCU updates
torture-test.2024.12.14a: Adding an extra test, fixes

One merge conflicts was detected by linux-next:

* https://lore.kernel.org/lkml/20241220133738.1beae531@canb.auug.org.au/T/

The conflict resolution from linux-next look good to me, plus I make
my own resolutions at branch merge/rcu.2024.12.21a for your reference.

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

RCU pull request for v6.14

This pull request contains the following branches:

fixes.2024.12.14a: Misc fixes, check if IRQs are disabled in rcu_exp_need_qs(),
    instrument KCSAN exclusive-writer assertions, add extra WARN_ON_ONCE() check,
    set the cpu_no_qs.b.exp under lock, warn if callback enqueued on offline CPU.

rcutorture.2024.12.14a: Torture-test updates, add rcutorture.preempt_duration kernel
    module parameter, make the TREE03 scenario do preemption, improve pooling timeouts
    for rcu_torture_writer(), improve output of "Failure/close-call rcutorture reader
    segments", add some reader-state debugging checks, update doc of polled APIs, add
    extra diagnostics for per-reader-segment preemption.

srcu.2024.12.14a: SRCU updates, improve doc for srcu_read_lock() in terms of return
    value, fix typo in comments, remove redundant GP sequence checks in the
    srcu_funnel_gp_start.

torture-test.2024.12.14a: Add an extra test for sched_clock(), improve testing
    on unresponsive systems.

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

Feng Lee (1):
  srcu: Remove redundant GP sequence checks in srcu_funnel_gp_start

Frederic Weisbecker (1):
  rcu: Report callbacks enqueued on offline CPU blind spot

Paul E. McKenney (29):
  refscale: Add test for sched_clock()
  torture: Make kvm-remote.sh give up on unresponsive system
  torture: Add dowarn argument to torture_sched_setaffinity()
  rcutorture: Add random real-time preemption
  rcutorture: Make the TREE03 scenario do preemption
  rcutorture: Decorate failing reader segments with CPU ID
  rcutorture: Use finer-grained timeouts for rcu_torture_writer() polling
  rcutorture: Add ->cond_sync_exp_full function to rcu_ops structure
  rcutorture: Check preemption for failing reader
  rcutorture: Decorate failing reader segments with last CPU ID
  rcutorture: Add full read-side contexts to "busted" torture type
  rcutorture: Pretty-print rcutorture reader segments
  rcutorture: Make rcutorture_one_extend() check reader state
  rcutorture: Ignore attempts to test preemption and forward progress
  rcutorture: Add documentation for recent conditional and polled APIs
  rcutorture: Add parameters to control polled/conditional wait interval
  rcutorture: Add preempt_count() to rcutorture_one_extend_check() diagnostics
  rcutorture: Read CPU ID for decoration protected by both reader types
  rcutorture: Add per-reader-segment preemption diagnostics
  rcutorture: Use symbols for SRCU reader flavors
  rcu: Make rcu_report_exp_cpu_mult() caller acquire lock
  rcu: Move rcu_report_exp_rdp() setting of ->cpu_no_qs.b.exp under lock
  rcu: Replace open-coded rcu_exp_need_qs() from rcu_exp_handler() with call
  rcu: Make preemptible rcu_exp_handler() check idempotency
  rcu: Add KCSAN exclusive-writer assertions for rdp->cpu_no_qs.b.exp
  rcu: Add lockdep_assert_irqs_disabled() to rcu_exp_need_qs()
  MAINTAINERS: Update RCU git tree
  srcu: Guarantee non-negative return value from srcu_read_lock()
  srcu: Fix typo s/srcu_check_read_flavor()/__srcu_check_read_flavor()/

 Documentation/admin-guide/kernel-parameters.txt                |   74 ++++++++++++++++++++
 MAINTAINERS                                                    |   10 +-
 Makefile                                                       |    2
 arch/x86/kernel/cpu/amd.c                                      |    2
 include/linux/rcupdate_wait.h                                  |   11 +++
 include/linux/srcu.h                                           |   15 ++--
 include/linux/srcutree.h                                       |    2
 include/linux/torture.h                                        |    2
 kernel/bpf/lpm_trie.c                                          |   44 +++++-------
 kernel/locking/locktorture.c                                   |    6 -
 kernel/rcu/Kconfig.debug                                       |   15 ++++
 kernel/rcu/rcutorture.c                                        |    2
 kernel/rcu/refscale.c                                          |   40 ++++++++++-
 kernel/rcu/srcutree.c                                          |    3
 kernel/rcu/tree.c                                              |    3
 kernel/rcu/tree_exp.h                                          |   20 +++--
 kernel/rcu/tree_plugin.h                                       |    1
 kernel/rcu/update.c                                            |    4 -
 scripts/mod/modpost.c                                          |    2
 scripts/package/install-extmod-build                           |    4 -
 tools/testing/selftests/bpf/.gitignore                         |    1
 tools/testing/selftests/bpf/Makefile                           |    2
 tools/testing/selftests/bpf/map_tests/lpm_trie_map_basic_ops.c |   10 --
 tools/testing/selftests/rcutorture/bin/kvm-remote.sh           |   25 +++++-
 tools/testing/selftests/rcutorture/configs/rcu/TREE03.boot     |    1
 include/linux/srcu.h                                           |   21 +++--
 include/linux/srcutree.h                                       |    8 --
 kernel/bpf/lpm_trie.c                                          |   87 +++++++++++++++---------
 kernel/rcu/Kconfig.debug                                       |   16 ++++
 kernel/rcu/rcutorture.c                                        |  279 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-----------------
 kernel/rcu/srcutree.c                                          |    5 -
 kernel/rcu/tree_exp.h                                          |  128 ++++++++++++++++++++++-------------
 kernel/rcu/tree_plugin.h                                       |    1
 tools/testing/selftests/bpf/map_tests/lpm_trie_map_basic_ops.c |  395 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 37 files changed, 1033 insertions(+), 235 deletions(-)