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! Changes in v2: - Add patch for Zabha dtbinding (Conor) - Fix cmpxchg128() build warnings missed in v1 - Make arch_cmpxchg128() fully ordered - Improve Kconfig help texts for both extensions (Conor) - Fix Makefile dependencies by requiring TOOLCHAIN_HAS_XXX (Nathan) - Fix compilation errors when the toolchain does not support the extensions (Nathan) - Fix C23 warnings about label at the end of coumpound statements (Nathan) - Fix Zabha and !Zacas configurations (Andrea) - Add COMBO spinlocks (Guo) - Improve amocas fully ordered operations by using .aqrl semantics and removing the fence rw, rw (Andrea) - Rebase on top "riscv: Fix fully ordered LR/SC xchg[8|16]() implementations" - Add ARCH_WEAK_RELEASE_ACQUIRE (Andrea) - Remove the extension version in march for LLVM since it is only required for experimental extensions (Nathan) - Fix cmpxchg128() implementation by adding both registers of a pair in the list of input/output operands Alexandre Ghiti (8): riscv: Implement cmpxchg32/64() using Zacas dt-bindings: riscv: Add Zabha ISA extension description riscv: Implement cmpxchg8/16() using Zabha riscv: Improve amocas.X use in cmpxchg() riscv: Implement arch_cmpxchg128() using Zacas riscv: Implement xchg8/16() using Zabha riscv: Improve amoswap.X use in xchg() 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 .../devicetree/bindings/riscv/extensions.yaml | 6 + .../locking/queued-spinlocks/arch-support.txt | 2 +- arch/riscv/Kconfig | 45 +++++ arch/riscv/Makefile | 6 + arch/riscv/include/asm/Kbuild | 4 +- arch/riscv/include/asm/cmpxchg.h | 188 ++++++++++++++---- 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 | 21 ++ 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 ++++++++++ 14 files changed, 385 insertions(+), 134 deletions(-) create mode 100644 arch/riscv/include/asm/spinlock.h create mode 100644 include/asm-generic/ticket_spinlock.h -- 2.39.2
