[RFC PATCH v4 00/25] RSEQ node id and virtual cpu id extensions

[Mathieu Desnoyers]

Extend the rseq ABI to expose a NUMA node ID and a vm_vcpu_id field.

The NUMA node ID field allows implementing a faster getcpu(2) in libc.

The virtual cpu id allows ideal scaling (down or up) of user-space
per-cpu data structures. The virtual cpu ids allocated within a memory
space are tracked by the scheduler, which takes into account the number
of concurrently running threads, thus implicitly considering the number
of threads, the cpu affinity, the cpusets applying to those threads, and
the number of logical cores on the system.

This series is based on the v5.19 tag.

Thanks,

Mathieu

Mathieu Desnoyers (25):
  rseq: Introduce feature size and alignment ELF auxiliary vector
    entries
  rseq: Introduce extensible rseq ABI
  rseq: Extend struct rseq with numa node id
  selftests/rseq: Use ELF auxiliary vector for extensible rseq
  selftests/rseq: Implement rseq numa node id field selftest
  lib: Invert _find_next_bit source arguments
  lib: Implement find_{first,next}_{zero,one}_and_zero_bit
  cpumask: Implement cpumask_{first,next}_{zero,one}_and_zero
  sched: Introduce per memory space current virtual cpu id
  rseq: Extend struct rseq with per memory space vcpu id
  selftests/rseq: Remove RSEQ_SKIP_FASTPATH code
  selftests/rseq: Implement rseq vm_vcpu_id field support
  selftests/rseq: x86: Template memory ordering and percpu access mode
  selftests/rseq: arm: Template memory ordering and percpu access mode
  selftests/rseq: arm64: Template memory ordering and percpu access mode
  selftests/rseq: mips: Template memory ordering and percpu access mode
  selftests/rseq: ppc: Template memory ordering and percpu access mode
  selftests/rseq: s390: Template memory ordering and percpu access mode
  selftests/rseq: riscv: Template memory ordering and percpu access mode
  selftests/rseq: Implement basic percpu ops vm_vcpu_id test
  selftests/rseq: Implement parametrized vm_vcpu_id test
  selftests/rseq: x86: Implement rseq_load_u32_u32
  selftests/rseq: Implement numa node id vs vm_vcpu_id invariant test
  selftests/rseq: parametrized test: Report/abort on negative cpu id
  tracing/rseq: Add mm_vcpu_id field to rseq_update

 fs/binfmt_elf.c                               |    5 +
 fs/exec.c                                     |    6 +
 include/linux/cpumask.h                       |   86 ++
 include/linux/find.h                          |  123 +-
 include/linux/mm.h                            |   25 +
 include/linux/mm_types.h                      |  110 +-
 include/linux/sched.h                         |    9 +
 include/trace/events/rseq.h                   |    7 +-
 include/uapi/linux/auxvec.h                   |    2 +
 include/uapi/linux/rseq.h                     |   22 +
 init/Kconfig                                  |    4 +
 kernel/fork.c                                 |   11 +-
 kernel/ptrace.c                               |    2 +-
 kernel/rseq.c                                 |   61 +-
 kernel/sched/core.c                           |   49 +
 kernel/sched/sched.h                          |  166 +++
 kernel/signal.c                               |    2 +
 lib/find_bit.c                                |   17 +-
 tools/include/linux/find.h                    |    9 +-
 tools/lib/find_bit.c                          |   17 +-
 tools/testing/selftests/rseq/.gitignore       |    5 +
 tools/testing/selftests/rseq/Makefile         |   20 +-
 .../testing/selftests/rseq/basic_numa_test.c  |  117 ++
 .../selftests/rseq/basic_percpu_ops_test.c    |   46 +-
 tools/testing/selftests/rseq/basic_test.c     |    4 +
 tools/testing/selftests/rseq/compiler.h       |    6 +
 tools/testing/selftests/rseq/param_test.c     |  157 ++-
 tools/testing/selftests/rseq/rseq-abi.h       |   22 +
 tools/testing/selftests/rseq/rseq-arm-bits.h  |  505 +++++++
 tools/testing/selftests/rseq/rseq-arm.h       |  701 +---------
 .../testing/selftests/rseq/rseq-arm64-bits.h  |  392 ++++++
 tools/testing/selftests/rseq/rseq-arm64.h     |  520 +------
 .../testing/selftests/rseq/rseq-bits-reset.h  |   10 +
 .../selftests/rseq/rseq-bits-template.h       |   39 +
 tools/testing/selftests/rseq/rseq-mips-bits.h |  462 +++++++
 tools/testing/selftests/rseq/rseq-mips.h      |  646 +--------
 tools/testing/selftests/rseq/rseq-ppc-bits.h  |  454 +++++++
 tools/testing/selftests/rseq/rseq-ppc.h       |  617 +--------
 .../testing/selftests/rseq/rseq-riscv-bits.h  |  410 ++++++
 tools/testing/selftests/rseq/rseq-riscv.h     |  529 +-------
 tools/testing/selftests/rseq/rseq-s390-bits.h |  474 +++++++
 tools/testing/selftests/rseq/rseq-s390.h      |  495 +------
 tools/testing/selftests/rseq/rseq-skip.h      |   65 -
 tools/testing/selftests/rseq/rseq-x86-bits.h  | 1036 ++++++++++++++
 tools/testing/selftests/rseq/rseq-x86.h       | 1193 +----------------
 tools/testing/selftests/rseq/rseq.c           |   86 +-
 tools/testing/selftests/rseq/rseq.h           |  229 +++-
 .../testing/selftests/rseq/run_param_test.sh  |    5 +
 48 files changed, 5286 insertions(+), 4692 deletions(-)
 create mode 100644 tools/testing/selftests/rseq/basic_numa_test.c
 create mode 100644 tools/testing/selftests/rseq/rseq-arm-bits.h
 create mode 100644 tools/testing/selftests/rseq/rseq-arm64-bits.h
 create mode 100644 tools/testing/selftests/rseq/rseq-bits-reset.h
 create mode 100644 tools/testing/selftests/rseq/rseq-bits-template.h
 create mode 100644 tools/testing/selftests/rseq/rseq-mips-bits.h
 create mode 100644 tools/testing/selftests/rseq/rseq-ppc-bits.h
 create mode 100644 tools/testing/selftests/rseq/rseq-riscv-bits.h
 create mode 100644 tools/testing/selftests/rseq/rseq-s390-bits.h
 delete mode 100644 tools/testing/selftests/rseq/rseq-skip.h
 create mode 100644 tools/testing/selftests/rseq/rseq-x86-bits.h

-- 
2.25.1