[0/7] Zacas/Zabha support and qspinlocks

Message

Alexandre Ghiti May 28, 2024, 3:10 p.m. UTC

This implements [cmp]xchgXX() macros using Zacas and Zabha extensions
and finally uses those newly introduced macros to add support for
qspinlocks: note that this implementation of qspinlocks satisfies the
forward progress guarantee.

Thanks to Guo and Leonardo for their work!

Alexandre Ghiti (5):
  riscv: Implement cmpxchg32/64() using Zacas
  riscv: Implement cmpxchg8/16() using Zabha
  riscv: Implement arch_cmpxchg128() using Zacas
  riscv: Implement xchg8/16() using Zabha
  riscv: Add qspinlock support based on Zabha extension

Guo Ren (2):
  asm-generic: ticket-lock: Reuse arch_spinlock_t of qspinlock
  asm-generic: ticket-lock: Add separate ticket-lock.h

 .../locking/queued-spinlocks/arch-support.txt |   2 +-
 arch/riscv/Kconfig                            |  35 ++++++
 arch/riscv/Makefile                           |  21 ++++
 arch/riscv/include/asm/Kbuild                 |   4 +-
 arch/riscv/include/asm/cmpxchg.h              | 114 ++++++++++++++++--
 arch/riscv/include/asm/hwcap.h                |   1 +
 arch/riscv/include/asm/spinlock.h             |  39 ++++++
 arch/riscv/kernel/cpufeature.c                |   1 +
 arch/riscv/kernel/setup.c                     |  18 +++
 include/asm-generic/qspinlock.h               |   2 +
 include/asm-generic/spinlock.h                |  87 +------------
 include/asm-generic/spinlock_types.h          |  12 +-
 include/asm-generic/ticket_spinlock.h         | 105 ++++++++++++++++
 13 files changed, 336 insertions(+), 105 deletions(-)
 create mode 100644 arch/riscv/include/asm/spinlock.h
 create mode 100644 include/asm-generic/ticket_spinlock.h